This document provides an overview of Android programming. It defines Android as an open-source operating system and development platform for mobile devices. Key points covered include Android's version history, core features and capabilities, the software stack and development framework, important terminology, and application fundamentals. Native Android applications like email, SMS, and maps are also briefly mentioned.

1. Android
Programming
Pasi
Manninen
JAMK
University
of
Applied
Sciences
Slide
version
Nov
20th,
2013

2. 1.
Android
IntroducDon
What
is
Android?
Android
Version
History
Features
Development
Framework
and
Android
SoMware
Stack
• A
few
important
Android
terms
to
understand
• Android
ApplicaDon
Fundamentals
•
•
•
•
Android
Programming,
Pasi
Manninen.
2

3. What
is
Android?
• 1.
A
free
open-­‐source
operaDng
system
for
mobile
devices
• 2.
An
open-­‐source
development
pla.orm
for
creaDng
mobile
and
applicaDons
• 3.
Devices
that
runs
Android
applicaDons
• Allows
coding
with
Java
language
• Based
on
the
Linux
kernel
• Open
(all
features
are
open
to
developer)
• All
applicaDons
are
equal
(core
and
3th
party)
• Really
fast
and
easy
applicaDon
development
• Developed
by
Google
and
the
Open
Handset
Alliance,
OHA
• Announced
5th
Nov,
2007
• h[p://en.wikipedia.org/wiki/Android_(operaDng_system)
Android
Programming,
Pasi
Manninen.
3

4. Open
Handset
Alliance
• OHA,
Group
of
technology
and
mobile
companies
• Android
is
the
first
complete,
open,
and
free
mobile
pla`orm
provided
by
OHA
• The
goal
is
offer
richer
experience
with
mobile
devices
(with
open
standards)
• Handset
manufacturers
don’t
need
to
pay
any
lisencing
fees
to
load
Android
on
their
devices
• h[p://www.openhandsetalliance.com
Android
Programming,
Pasi
Manninen.
4

5. Android
Version
History
• Android
has
seen
a
number
of
updates
since
its
original
release
(July
22nd,
2013):
h[p://en.wikipedia.org/wiki/Ice_Cream_Sandwich_(operaDng_system)#Android_4.0.x_Ice_Cream_Sandwich
Android
Programming,
Pasi
Manninen.
5

6. NaDve
Android
ApplicaDons
•
•
•
•
•
•
•
•
•
•
•
•
•
An
e-­‐mail
client
An
SMS
management
applicaDon
A
full
PIM
(Calendar,
Contacts,
...)
A
WebKit-­‐based
wed
browser
A
music
player
and
picture
gallery
A
Camera
and
video
recording
apps
The
Home
Screen
The
Android
Market
(Google
mobile)
Google
Maps
(Google
mobile)
Gmail
Client
(Google
Mobile)
Google
Talk
(Google
Mobile)
YouTube
video
Player
(Google
Mobile)
…
Android
Programming,
Pasi
Manninen.
6

7. Features
(Android
SDK)
• GSM,
EDGE,
3G,
Wi-­‐Fi
networks
for
telephony
or
data
transfer
• LocaDon
based
services
as
GPS,
Google
Maps,
Geocoding
• Full
mulDmedia
control
(playback
and
recording
with
camera
and
microphone),
formats
MPEG4,
H.264,MP3,AAC,AMR,JPG,PNG,GIF...
• Sensors,
accelerometers,
compass
• Bluetooth
• Shared
data
stores
(SQLite,
Preferenses,
Content
Providers)
• Home-­‐Screen
widgets,
Live
Folders,
Live
Wallpapers
• An
integrated
WebKit-­‐based
browser
• Hardware
accelerated
graphics
(OpenGL
ES
2.0)
• Background
applicaDons
and
processes
• No
licensing,
distribuDon
or
development
fees
• …
Android
Programming,
Pasi
Manninen.
7

8. Development
Framework
• Android
applicaDons
are
wri[en
with
Java
• Programs
are
executed
in
custom
virtual
machine
called
Dalvik
• Each
applicaDon
runs
its
own
process
in
Dalvik
• SDK
gives
all
what
you
need
start
developing,
tesDng
and
debugging
your
applicaDon
– Android
API
– Development
tools
– Android
Virtual
Device
Manager
and
Emulator
– Full
documentaDon
with
sample
codes
– Online
support
h[p://developer.android.com
Android
Programming,
Pasi
Manninen.
8

9. Android
SoMware
Stack
Android
Programming,
Pasi
Manninen.
9

10. A
few
important
Android
“terms”
•
AcDvity
–
•
ApplicaDon
Class
–
•
A
component
that
does
nothing
but
receive
and
react
to
broadcast
announcements
Views
–
–
•
”intenDon”
to
do
some
work
in
your
applicaDon
Asynchronous
messages
which
holds
the
content
of
the
message
IntentReceiver
–
•
Makes
a
specific
set
of
the
applicaDon's
data
available
to
other
applicaDons
Intent
–
–
•
Doesn’t
have
visual
interface,
runs
background
for
an
indefinite
period
of
Dme
ContentProvider
–
•
Differences
to
AcDvity
based
applicaDons:
maintain
applicaDon
state
and
it
is
easy
to
transfer
objects
and
use
resources
between
components
Service
–
•
A
single
visual
user
interface,
applicaDon
is
made
up
of
one
or
more
AcDviDes
User
interface
elements
like
a
Bu[on
or
a
Label
or
lots
of
other
UI
elements
Hierarchical
structure
Home
Screen
Widgets
–
ApplicaDons
that
can
be
run
in
Android
devices
home
screen
(can
be
an
entry
point
to
real
applicaDon
also)
Android
Programming,
Pasi
Manninen.
10

11. Android
ApplicaDon
Fundamentals
• Android
applicaDon
lives
in
its
own
world
– Every
applicaDon
runs
in
its
own
process
– Each
applicaDon
is
assigned
a
unique
Linux
user
ID,
applicaDon
files
are
visible
only
that
user
and
applicaDon
(permissions)
• ApplicaDon
can
make
use
of
elements
of
other
applicaDons
• System
must
be
able
to
start
an
applicaDon
process
when
any
part
of
it
is
needed
Android
Programming,
Pasi
Manninen.
11

12. 2.
Set
up
a
complete
Android
development
environment
•
•
•
•
System
requirements
Installing
Java
Serng
up
the
ADT
Bundle
Hands-­‐on
training:
– Install
and
configure
Android
development
environment
Android
Programming,
Pasi
Manninen.
12

13. System
Requirements
• OperaDng
systems
– Windows
XP
(32-­‐bit),
Vista
(32-­‐
or
64-­‐bit),
or
Windows
7
(32-­‐
or
64-­‐bit)
– Mac
OS
X
10.5.8
or
later
(x86
only)
– Linux
(tested
on
Ubuntu
Linux,
Lucid
Lynx)
• Eclipse
IDE
3.6.2
or
later,
JDT-­‐plugin
• JDK
6
(or
later)
Android
Programming,
Pasi
Manninen.
13

14. Installing
Java
• Needed
Java
JDK
can
be
download
from
Oracle
site:
– h[p://www.oracle.com/technetwork/java/javase/
downloads/index.html
• Remember
download
right
version
of
Java
(32
or
64
bit)
Android
Programming,
Pasi
Manninen.
14

15. Serng
up
the
ADT
Bundle
• To
get
started
go
to
– h[p://developer.android.com/sdk/index.html
• Download
the
SDK
and
unpack
the
ZIP
file
to
appropriate
locaDon
• Open
Eclipse
from
eclipse
folder
• Install
addiDonal
version
of
Android
or
other
needed
packages
with
SDK
Manager
Android
Programming,
Pasi
Manninen.
15

16. Install
and
Configure
Android
development
environment
• Hands-­‐on
training:
– Download
and
install
Java
JDK
– Download
and
install
the
Android
SDK
(it
installs
eclipse
too)
– Start
eclipse
and
Android
SDK
Manager
– Add
needed
Android
packages
and
other
extras
Android
Programming,
Pasi
Manninen.
16

17. 3.
CreaDng
a
first
Android
ApplicaDon
•
•
•
•
CreaDng
Android
Project
in
Eclipse
Running
applicaDon
in
Emulator
Running
applicaDon
in
Device
Debugging
applicaDon
– Eclipse
debug
perspecDve
– Dalvik
Debug
Monitor
Service
(DDMS)
• Hands-­‐on
training:
– Hello
Android!
Android
Programming,
Pasi
Manninen.
17

18. CreaDng
an
Android
Project
in
Eclipse
• Android
project
contains
all
the
files
that
comprise
the
source
code
for
your
Android
app
• Android
SDK
tools
make
it
easy
to
start
a
new
Android
project
with
a
set
of
default
project
directories
and
files
• Select
File
>
New
>
Android
ApplicaDon
Project
from
Eclipse
• A
few
dialogs
will
be
shown
to
configure
your
applicaDon
default
serngs
Android
Programming,
Pasi
Manninen.
18

19. Running
applicaDon
in
Emulator
• With
ADT
running
your
applicaDon
does
following:
– Current
project
compiles
and
converts
to
Android
executable
(.dex)
– Executable
and
resources
will
be
packed
into
an
Android
package
(.apk)
– Selected
virtual
device
will
be
started
and
your
applicaDon
will
be
installed
and
started
• Needed
emulators
(virtual
devices)
can
be
created
with
Android
Virtual
Device
Manager
(AVD)
Android
Programming,
Pasi
Manninen.
19

20. Running
applicaDon
in
device
• Device
has
to
be
plugged
to
development
machine
with
USB
cable
• USB
debugging
has
to
be
enabled
in
device
• Select
Run
ConfiguraDons…
and
choose
device
from
Android
Device
Chooser
Android
Programming,
Pasi
Manninen.
20

21. Debugging
applicaDon
• The
Debug
PerspecDve
in
Eclipse
– Use
Debug,
Variables,
Breakpoints
and
LogCat
tabs
in
Eclipse
• The
DDMS
(Dalvik
Debug
Monitor
Service)
PerspecDve
– Show
the
AVDs
and
real
devices
list
– Emulator
controls
(locaDon,
phone
call,
…)
– Processes,
Threads,
heap,
memory
allocaDon,
files,
…
Android
Programming,
Pasi
Manninen.
21

22. CreaDng
a
first
Android
ApplicaDon
• Hands-­‐on
training
:
Hello
Android!
– Create
a
new
Android
Project
– Create
first
Android
ApplicaDon
– Run,
debug
and
test
in
an
emulator
and
real
device
– DDMS,
Dalvik
Debug
Monitor
Service
Android
Programming,
Pasi
Manninen.
22

23. 4.
Publishing
ApplicaDon
to
Google
Play
• ApplicaDon
Requirements
• Signing
the
ApplicaDon
– Strategy
– Debug
and
Public
Release
• Google
Play
– ApplicaDon
LisDng
– Uploading
a
new
ApplicaDon
Android
Programming,
Pasi
Manninen.
23

24. ApplicaDon
Requirements
• ApplicaDon
must
be
signed
with
private
key,
validity
period
ends
aMer
22
October
2033
• ApplicaDon
must
define
both
an
android:versionCode
and
an
android:versionName
a[ribute
in
the
manifest
file
• ApplicaDon
must
define
both
an
android:icon
and
an
android:label
a[ribute
in
the
<applica:on>
element
of
its
manifest
<manifest
xmlns:android="h[p://schemas.android.com/apk/res/android"
package="fi.ptm.nameday"
android:versionCode="8"
android:versionName="1.0.6">
<applicaDon
android:icon="@drawable/icon"
android:label="@string/app_name">
...
Android
Programming,
Pasi
Manninen.
24

25. Signing
the
ApplicaDon
• All
Android
apps
must
be
signed
– the
system
will
not
install
an
applicaDon
that
is
not
signed
• You
can
use
self-­‐signed
cerDficates
to
sign
your
applicaDons
– no
cerDficate
authority
is
needed
• ApplicaDon
must
be
signed
it
with
a
suitable
private
key
before
publishing
to
Android
Market
– By
default
applicaDon
is
signed
with
debug
key
(generated
with
SDK
Tools
in
Eclipse)
• The
system
tests
a
signer
cerDficate's
expiraDon
date
only
at
install
Dme
• You
can
use
standard
tools
to
generate
keys
and
sign
your
applicaDon
.apk
files
– Keytool
and
Jarsigner
(in
command
line)
– ADT
Export
Wizard
in
Eclipse
Android
Programming,
Pasi
Manninen.
25

26. Signing
Strategy
• Use
same
cerDficate
for
all
applicaDons
– applicaDon
upgrade
(seamless)
– applicaDon
modularity
(same
process)
– code
and
data
sharing
(through
permissions)
• Validity
period
of
cerDficate
exceeds
the
expected
lifespan
of
applicaDon
– validity
period
of
25
years
or
more
is
recommended
(no
upgrades)
– Android
Market
(validity
period
ending
aMer
22
October
2033)
Android
Programming,
Pasi
Manninen.
26

27. Signing
in
Debug
Mode
• The
Android
build
tools
provide
a
debug
signing
mode
• ADT
generates
a
debug
cerDficate
automaDcally
for
emulator
and
device
– Keystore
name:
"debug.keystore"
– Keystore
password:
"android"
– Key
alias:
"androiddebugkey"
– Key
password:
"android"
– CN:
"CN=Android
Debug,O=Android,C=US“
– Keystore
is
located
in
your
home
directory’s
.android
dir
• Debug
cerDficates
expire
aMer
365
days
aMer
creaDon
Android
Programming,
Pasi
Manninen.
27

28. Signing
Public
Release
•
•
•
•
•
Make
sure
that
your
applicaDon
is
ready
Obtain
a
suitable
private
key
Compile
applicaDon
in
release
mode
Sign
applicaDon
with
private
key
On
Eclipse
right-­‐click
on
your
project
folder
– select
Android
Tools
>
Export
Unsigned
ApplicaDon
Package
– select
File
>
Export
to
export
signed
APK,
select
Export
Android
ApplicaDon
Android
Programming,
Pasi
Manninen.
28

29. Publish
-­‐
KeyStore
• Create
a
new
KeyStore
if
needed
• Remember
your
password
Android
Programming,
Pasi
Manninen.
29

30. Publish
–
Key
CreaDon
• KeyStore
Alias
for
later
use
• Validity
period
• Personal,
corporate
or
organizaDon
idenDficaDon
Android
Programming,
Pasi
Manninen.
30

31. Publish
–
Signed
APK
File
• Enter
desDnaDon
for
the
APK
file
• APK
file
is
ready
to
publish
in
Android
Market
Android
Programming,
Pasi
Manninen.
31

32. Google
Play
• Google
Play
is
a
hosted
service
– easy
for
users
to
find
and
download
Android
applicaDons
– easy
for
developers
to
publish
their
applicaDons
• To
publish
your
applicaDon
on
Google
Play
– register
with
the
service
using
your
Google
account
– agree
to
the
terms
of
service
– developer
fee
is
$25
(Iphone
developer
cost
is
$99)
• Once
published,
users
can
see
your
applicaDon,
download
it,
and
rate
it
using
the
Play
applicaDon
installed
on
their
Android-­‐powered
devices
• h[ps://play.google.com/apps/publish/
Android
Programming,
Pasi
Manninen.
32

33. ApplicaDon
LisDngs
• All
applicaDons
are
listed
nicely
with
basic
informaDon
– Name,
download
counts,
stars
and
so
on
Android
Programming,
Pasi
Manninen.
33

34. Uploading
applicaDon
• ApplicaDon
uploading
is
easy
• You
can
add
a
screenshots
and
promoDonal
graphics
Android
Programming,
Pasi
Manninen.
34

35. ApplicaDon
Details
• Select:
– languages
– descripDon
– app
type
and
category
– price
– protecDon
Android
Programming,
Pasi
Manninen.
35

36. Contact
InformaDons
• Select
Copy
protecDon
• Give
contact
InformaDon
• And
Publish!
Android
Programming,
Pasi
Manninen.
36

37. 5.
Directory
Structure
of
an
Android
ApplicaDon
Project
• Android
ApplicaDon
Project
folder
• Android
ApplicaDon
Resources
• Resource
examples:
– strings.xml
– colors.xml
• AndroidManifest.xml
• AndroidManifest.xml
example:
– HelloAndroid
project
• SupporDng
different
languages
and
hardwares
• Exercise:
Texts,
colors
and
localizaDon
Android
Programming,
Pasi
Manninen.
37

38. Android
ApplicaDon
Project
folder
• Android
project
holds
all
the
code
and
resources
in
different
folders.
• Some
of
the
folders
are
generated
by
default
and
some
has
to
be
done
by
self
if
needed
src
(all
source
codes)
gen
(Java
files
generated
by
ADT)
assets
(used
for
example
store
raw
asset
files)
bin
(output
directory,
apk
is
here)
res
(resources
of
the
applicaDon)
res/drawable
(image
and
image-­‐descriptor
files)
res/layout
(views
of
the
applicaDon)
res/menu
(applicaDon
menus)
res/values
(other
resources
of
the
applicaDon)
…
– Strings,
styles,
colors
and
so
on...
(xml
based)
Android
Programming,
Pasi
Manninen.
38

39. Android
ApplicaDon
Resources
• It
is
good
to
keep
non-­‐code
resources
(images,
strings,
animaDon,
themes,
layouts)
external
to
code
• Easy
to
maintain,
update
and
manage
• Supports
different
devices
and
localizaDon
• Android
selects
resources
dynamically
in
runDme
(no
need
to
code)
• ApplicaDon
resources
are
stored
under
res/
folder
–
–
–
–
–
res/anim
(frame
by
frame
animaDons)
res/drawable
(bitmaps,
other
types
drawable
types)
res/layout
(UI
layouts)
res/menu
(menu
layouts)
res/values
(different
resources)
for
example
• arrays.xml,
colors.xml,
dimens.xml,
strings.xml,
styles.xml,
themes.xml
– res/xml
(arbitrary
XML
files)
•
•
Resources
can
be
used
from
code
or
from
other
recources
System
Resources
are
defined
under
android.R
Android
Programming,
Pasi
Manninen.
39

40. Resource
example:
strings.xml
• Easy
to
update
later,
localizaDon
<?xml
version="1.0"
encoding="u/-­‐8"?>
<resources>
<string
name="app_name">NameDay</string>
<string
name="widget_header">Nameday's</string>
<string
name="widget_footer">(c)
2013
PTM</string>
</resources>
Used
in
main.xml
layout
(for
example):
<TextView
android:id=”@+id/text”
android:text=”@string/widget_header”
/>
//
Used
in
code:
CharSequence
str
=
getString(R.string.widget_header);
TextView
tv
=
(TextView)
findViewById(R.id.text);
tv.setText(str);
Android
Programming,
Pasi
Manninen.
40

41. Resource
example:
colors.xml
• Stored
in
res/values
folder
• It
is
good
pracDce
to
keep
all
color
values
in
same
file
• Used
same
way
as
strings
in
earlier
example
<?xml
version="1.0"
encoding="u/-­‐8"?>
<resources>
<color
name="opaque_blue">#00F</color>
<color
name="transparent_green">#7700FF00</color>
<color
name="Ptle_color_dark">#FF860000</color>
</resources>
Android
Programming,
Pasi
Manninen.
41

42. AndroidManifest.xml
• ApplicaDon
descriptor
file
• Defines
your
applicaDon
– AcDviDes
– ContentProviders
– Services
– Intent
Receivers
– Permissions
– Version
number
–
and
a
lots
of
more...
Android
Programming,
Pasi
Manninen.
42

43. AndroidManifest.xml
example:
HelloAndroid
project
<?xml
version="1.0"
encoding="u/-­‐8"?>
<manifest
xmlns:android="hTp://schemas.android.com/apk/res/android"
package="fi.ptm.helloandroid"
android:versionCode="1"
android:versionName="1.0"
>
<uses-­‐sdk
android:minSdkVersion="16"
android:targetSdkVersion="17"
/>
<applicaDon
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme"
>
<acDvity
android:name="fi.ptm.helloandroid.MainAcPvity"
android:label="@string/app_name"
>
<intent-­‐filter>
<acDon
android:name="android.intent.acPon.MAIN"
/>
<category
android:name="android.intent.category.LAUNCHER"
/>
</intent-­‐filter>
</acDvity>
</applicaDon>
</manifest>
Android
Programming,
Pasi
Manninen.
43

44. Different
languages
and
hardware
• Like
said
Android
has
dynamic
resource
selecDon
mechanism
• All
is
done
with
using
directory
structure
• Spesific
languages,
locaDons
and
hardware
• AlternaDves
are
described
with
–
mark
For
example
project:
-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐
res/layout/main.xml
res/layout-­‐land/main.xml
res/values-­‐fi/strings.xml
res/values-­‐en/strings.xml
Android
Programming,
Pasi
Manninen.
44

45. Support
different
screen
sizes
• Portrait
and
lanscape
modes
can
be
easily
done
with
resources
• Portrait
mode
is
created
automaDcally
when
project
is
done
(layout)
• Create
a
new
folder
(layout-­‐
land)
for
landscape
acDviDes
• Android
switches
layouts
automaDcally
when
new
mode
is
detected
Android
Programming,
Pasi
Manninen.
45

46. Support
different
languages
• Language
support
is
done
via
resources
also
• Default
language
strings
are
stored
to
values
folder
• Create
a
new
values-­‐
(language
code)
folder
for
all
supported
languages
– For
example
values-­‐fi
for
Finnish
• Android
automaDcally
uses
right
values
folder
if
device
switches
language
Android
Programming,
Pasi
Manninen.
46

47. Exercise:
Texts,
Colors
and
LocalizaDon
• Create
an
applicaDon
with
a
few
TextViews
with
different
colors
and
texts
(use
XML
files).
Make
a
few
localizaDon
test
(for
example
fi)
and
test
localizaDon
in
emulator.
Android
Programming,
Pasi
Manninen.
47

48. 6.
AcDviDes
and
User
Interface
•
•
•
•
•
•
•
•
•
•
•
What
is
AcDvity?
AcDviDes
and
tasks
StarDng
process
and
threads
AcDvity
lifecycle
Declaring
acDvity
in
the
manifest
Basics
of
the
Views
and
Layouts
Defining
layouts
with
XML
How
Android
draws
a
view
(AcDvity)
Common
Layouts
and
Controls
with
examples
Handling
UI
events
Exercise:
Basic
UI
Controls
Android
Programming,
Pasi
Manninen.
48

49. What
is
AcDvity?
• ApplicaDon
component
(user
interface)
that
provides
a
screen
which
user
can
interact
to
do
something
• ApplicaDon
usually
contains
a
mulDple
acDviDes
which
makes
the
whole
applicaDon
• Typically,
one
acDvity
in
an
applicaDon
is
specified
as
the
main
acDvity,
which
is
presented
to
the
user
when
launching
the
applicaDon
for
the
first
Dme
• Each
acDvity
can
then
start
another
acDvity
in
order
to
perform
different
acDons
• AcDviDes
are
subclasses
from
AcDvity
class
• Developer
implements
callback
methods
that
the
system
calls
different
states
of
the
applicaDon
(AcDvity)
Android
Programming,
Pasi
Manninen.
49

50. AcDviDes
and
tasks
• A
task
is
what
the
user
experiences
as
an
applicaDon
• Task
is
like
a
collecDon
of
AcDvites
what
runs
in
same
applicaDon
• All
acDviDes
are
set
in
the
stack
• The
root
acDvity
in
the
stack
is
the
one
that
began
the
task
(the
applicaDon
launcher)
• AcDvity
at
the
top
of
the
stack
is
one
that's
currently
running
• The
previous
acDviDes
remains
in
the
stack
and
are
paused/
stopped
(acDvated
when
user
presses
back
bu[on)
• By
default,
all
the
acDviDes
in
an
applicaDon
have
an
affinity
for
each
other
(name
of
the
.apk
package
name)
Android
Programming,
Pasi
Manninen.
50

51. StarDng
process
and
threads
• When
the
first
of
an
applicaDon's
components
needs
to
be
run,
Android
starts
a
Linux
process
for
it
with
a
single
thread
of
execuDon
• The
process
where
a
component
runs
is
controlled
by
the
manifest
file
•
Note!
• Android
may
decide
to
shut
down
a
process
at
some
point
• Everything
runs
in
the
main
thread
(including
UI),
avoid
long
lasDng
operaDons
– Maintain
UI
responsive
– Use
another
thread
(AsyncTask)
for
the
long
operaDons
Android
Programming,
Pasi
Manninen.
51

52. AcDvity
lifecycle
• Three
main
states:
running,
paused
and
stopped
• If
an
acDvity
is
paused
or
stopped,
the
system
can
drop
it
from
memory
• Do
your
applicaDon
UI,
bind
Data
sources
and
event
handlers
in
onCreate()
• AMer
onResume()
acDvity
is
visible
to
end
user
• In
onPause()
save
criDcal
data
to
applicaDon’s
data
store
Note:
This
will
be
discussed
more
deeply
later…
Android
Programming,
Pasi
Manninen.
52

53. Declaring
acDvity
in
the
manifest
• AcDvity
has
to
be
declared
in
the
manifest
file
• Use
android:name
a[ribute
to
specify
the
class
name
of
the
acDvity
• Use
other
a[ributes
to
add
addiDonal
informaDon
of
the
acDvity
(label,
icon,
theme,
…)
• Use
Intent
filters
if
you
want
to
make
your
acDvity
available
to
system
or
other
applicaDons
<acDvity
android:name="fi.ptm.helloandroid.MainAcPvity”
android:label="@string/app_name"
>
<intent-­‐filter>
<acDon
android:name="android.intent.acPon.MAIN"
/>
<category
android:name="android.intent.category.LAUNCHER"
/>
</intent-­‐filter>
</acDvity>
Android
Programming,
Pasi
Manninen.
53

54. Basics
of
the
Views
and
Layouts
• Android
applicaDon
UI
is
built
using
View
and
ViewGroup
objects
• Bu[on,
Text
(and
so
on
UI
objects)
are
View’s
subclasses
and
they
are
called
as
”widgets”
or
”Views”
• Layout
architectures
like
linear,
tabular
and
relaDve
are
ViewGroup’s
subclasses
and
they
are
called
as
“Layouts”
Android
Programming,
Pasi
Manninen.
54

55. Defining
layouts
with
XML
• Most
common
way
is
to
use
XML
layout
for
declaring
AcDvity
layout
• Each
element
in
XML
is
either
a
View
or
ViewGroup
object
• View
objects
are
leaves
in
the
tree,
ViewGroup
objects
are
branches
in
the
tree
• The
name
of
an
XML
element
is
respecDve
to
the
Java
class
that
it
represents
like:
<TextView>
element
creates
a
TextView
in
your
UI
• Layout
and
its
elements
can
be
instanDate
at
runDme
programmaDcally
also
Android
Programming,
Pasi
Manninen.
55

56. How
Android
draws
a
view
• A[ach
the
view
hierarchy
tree
to
the
screen,
AcDvity
must
call
the
setContentView()
method
and
pass
a
reference
to
the
root
node
object
• The
draw()
method
of
a
View
is
called
• Two
process:
measure
and
layout
pass
• Mostly
used
layout
params:
– Exact
number
– match_parent,
view
wants
to
be
as
big
as
its
parent
– wrap_content,
view
wants
to
be
just
big
enough
to
enclose
its
content
• Size,
Padding,
Margins
is
used
like
in
HTML
• Dimensions:
dp,
sp,
pt,
px,
mm
and
in
• Different
Views
and
Layouts
has
its
own
subclass
of
Layout
Params
Android
Programming,
Pasi
Manninen.
56

57. Common
Layouts
• FrameLayout
– a
blank
space
on
your
screen
that
you
can
later
fill
with
a
single
object
• LinearLayout
– aligns
all
children
in
a
single
direcDon
(verDcally
or
horizontally)
– all
children
are
stacked
one
aMer
the
other
• TableLayout
– posiDons
its
children
into
rows
and
columns
– doesn’t
display
border
lines
for
their
rows,
columns,
or
cells
• RelaDveLayout
– child
views
specify
their
posiDon
relaDve
to
the
parent
view
or
to
each
other
• More:
– Gallery,
GridView,
ListView,
ScrollView,
Spinner,
SurfaceView,
TabHost,
ViewFlipper,
ViewSwitcher,
Fragments,
WebView,…
Android
Programming,
Pasi
Manninen.
57

58. LinearLayout
example
<!–
ac:vity_main.xml-­‐-­‐>
<LinearLayout
xmlns:android="hTp://schemas.android.com/apk/res/android"
xmlns:tools="hTp://schemas.android.com/tools”>
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hello_world"
/>
<Bu[on
android:id="@+id/buTon1"
android:layout_width="wrap_content"
android:layout_height="wrap_content”
android:text="@string/buTon_string"
/>
</LinearLayout>
//
load
acDvity_main.xml
public
void
onCreate(Bundle
savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.ac:vity_main);
}
Android
Programming,
Pasi
Manninen.
58

59. RelaDveLayout
example
<RelaDveLayout
xmlns:android="hTp://schemas.android.com/apk/res/android"
xmlns:tools="hTp://schemas.android.com/tools"
xmlns:ads="hTp://schemas.android.com/apk/lib/com.google.ads"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainAcPvity"
>
<com.google.ads.AdView
android:id="@+id/adView"
android:layout_width="match_parent"
android:layout_height="50dip"
ads:adUnitId=”xxxxxxx"
ads:adSize="BANNER"
ads:testDevices="TEST_EMULATOR,
TEST_DEVICE_ID"
ads:loadAdOnCreate="true"
android:layout_alignParentBoOom="true"
/>
…
Android
Programming,
Pasi
Manninen.
59

60. RelaDveLayout
example
…
<TableLayout
android:id="@+id/keypad"
android:orientaDon="verPcal"
android:layout_width="fill_parent"
android:layout_height="wrap_content”
android:stretchColumns="*”
android:layout_above="@+id/adView”>
<TableRow>
<Bu[on
android:id="@+id/keypad_1"
android:text="1"
android:onClick="buTonClicked"></BuTon>
<Bu[on
android:id="@+id/keypad_2"
android:text=“2"
android:onClick="buTonClicked"></BuTon>
…
</TableRow>
…
</TableLayout>
…
Android
Programming,
Pasi
Manninen.
60

61. RelaDveLayout
example
…
<HorizontalScrollView
android:id="@+id/scrollView"
android:layout_width="fill_parent"
android:layout_height="75dp"
android:layout_above="@+id/keypad"
android:paddingTop="2dp"
android:paddingBo[om="2dp"
>
<LinearLayout
android:id="@+id/linearLayoutOfImages"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientaDon="horizontal">
</LinearLayout>
</HorizontalScrollView>
…
Android
Programming,
Pasi
Manninen.
61

62. RelaDveLayout
example
…
<fi.ptm.teksDtv.AspectRaDoImageView
android:layout_centerHorizontal="true"
android:id="@+id/imageView"
android:src="@drawable/ladataan"
android:layout_alignParentTop="true"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:adjustViewBounds="true"/>
<TextView
android:id="@+id/pageTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeR="true"
android:text="100/01"
android:background="#FFFFFF"
android:textColor="#000000"/>
</RelaDveLayout>
Android
Programming,
Pasi
Manninen.
62

63. Common
Input
Controls
• Input
controls
are
the
interacDve
components
in
your
applicaDon’s
user
interface
• Android
provides
a
wide
variety
of
controls
to
use
in
your
UI
– Bu[ons,
text
fields,
seek
bars,
checkboxes,
spinners,
pickers
and
so
on…
• All
controls
can
be
found
in
layout
pale[e
• Use
drag
and
drop
to
set
controls
to
layout
or
edit
your
XML
file
directly
Android
Programming,
Pasi
Manninen.
63

64. Handling
UI
Events
• Many
ways
to
intercept
the
events
from
a
user's
interacDon
(depends
the
SDK
version)
• The
approach
is
to
capture
the
events
from
the
specific
View
object
that
the
user
interacts
with
• Use
different
EventListeners
with
code
or
in
XML
– onClick,
onLongClick,
onFocusChange,
…
Android
Programming,
Pasi
Manninen.
64

65. Example:
Handling
UI
Events
• Only
with
coding
//
Create
an
implementaDon
of
OnClickListener
private
OnClickListener
buOon1Listener
=
new
OnClickListener()
{
public
void
onClick(View
v)
{
//
Do
something
when
the
bu[on
is
clicked
Toast.makeText(getApplicaDonContext(),
"Bu[on
1
clicked",
Toast.LENGTH_SHORT).show();
}
};
@Override
protected
void
onCreate(Bundle
savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.acDvity_main);
//
Capture
our
bu[on
from
layout
Bu[on
buOon1
=
(Bu[on)findViewById(R.id.bu[on1);
//
Register
the
onClick
listener
with
the
implementaDon
above
buOon1.setOnClickListener(buOon1Listener);
}
• With
XML
and
code
<Bu[on
android:id="@+id/bu[on2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/bu[on1"
android:layout_centerHorizontal="true"
android:layout_marginTop="19dp"
android:onClick="buOon2Clicked"
android:text="OnClick
with
XML"
/>
public
void
buOon2Clicked(View
view)
{
Toast.makeText(getApplicaDonContext(),
"Bu[on
2
clicked",
Toast.LENGTH_SHORT).show();
}
Android
Programming,
Pasi
Manninen.
65

66. Bu[ons
Example
• Different
bu[on
types
– Bu[on
with
text
– Bu[on
with
text
and
image
– ImageBu[on
with
image
• Responding
Click
Events
– onClick
– OnClickListener
Android
Programming,
Pasi
Manninen.
66

67. Text
Fields
Example
• Use
TextView
to
show
text
• Use
EditText
to
ask
text
from
the
end
user
– automaDcally
displays
the
keyboard
– different
input
types
(android:inputType)
• text,
textEmailAddress,
textUri,
number,
phone
• textCapSentences,
textCapWords,
textAutoCorrecDon,
textPassword,
textMulDline
– text
selecDon
• cut,
copy,
paste
– auto-­‐compleDon
• use
AutoCompleteTextView
• define
the
array
that
contains
all
text
suggesDons
in
strings
resource
• create
String
based
Adapter
in
code
and
and
use
it
in
your
AutoCompleteTextView
Android
Programming,
Pasi
Manninen.
67

68. CheckBoxes,
Radio
and
Toggle
Bu[ons
Example
• Checkboxes
allow
the
user
to
select
one
or
more
opDons
from
a
set
• Radio
bu[ons
allow
the
user
to
select
one
opDon
from
a
set
• A
toggle
bu[on
or
switch
allows
the
user
to
change
a
serng
between
two
states
Android
Programming,
Pasi
Manninen.
68

69. Spinner
Example
• Provides
a
quick
way
to
select
one
value
from
a
set
• Touching
the
spinner
displays
a
dropdown
menu
with
all
other
available
value
(user
can
select
one)
• Define
String
resource
and
create
String
based
Adapter
in
code
and
use
it
to
your
Spinner
Android
Programming,
Pasi
Manninen.
69

70. Pickers
Example
• Android
provides
controls
for
the
user
to
pick
a
Dme
or
pick
a
date
as
ready-­‐to-­‐use
dialogs
• Using
these
pickers
helps
ensure
that
your
users
can
pick
a
Dme
or
date
that
is
valid,
forma[ed
correctly,
and
adjusted
to
the
user's
locale
• It
is
recommended
to
use
DialogFragment
to
display
Dme
or
date
picker
Android
Programming,
Pasi
Manninen.
70

71. Exercise:
Basic
UI
Controls
• RadioBu[ons
and
selecDon
• Different
texts
controls
Android
Programming,
Pasi
Manninen.
71

72. 7.
Menus,
NoDfying
and
Dialogs
•
Working
with
Menus
–
–
–
–
–
–
–
Using
OpDons
Menu
Example:
OpDons
Menu
with
XML
Contextual
Menus
Using
Context
Menu
Examples
with
Context
Menu
Using
Contextual
AcDon
Mode
Using
PopUp
Menu
•
NoDfying
the
User
•
NoDfying
the
user
with
Dialogs
– NoDfying
with
the
Toast
– Example:
Display
Toasts
– Using
NoDficaDon
Area
–
–
–
–
–
–
–
CreaDng
a
Dialog
Examples:
AlertDialog
with
Bu[ons
and
List
Custom
Dialog
Layouts
Examples:
Custom
Dialog
Passing
Events
back
to
Dialog’s
Host
ProgressDialog,
ProgressBar
and
Indicators
Example:
ProgressBar
Android
Programming,
Pasi
Manninen.
72

73. Working
with
Menus
• OpDons
Menu
– primary
set
of
menu
items
for
an
AcDvity
– opened
by
pressing
the
device
MENU
key
– two
groups
of
menu
items:
• Icon
Menu
• Expanded
Menu
• Context
Menu
– floaDng
list
of
menu
items
– appear
when
you
perform
a
long-­‐press
on
a
View
(like
right
click
in
PC)
• PopUp
– a
modal
menu
anchored
to
a
View
– appears
below
the
anchor
view
if
there
is
room,
or
above
the
view
otherwise
Android
Programming,
Pasi
Manninen.
73

74. Using
OpDons
Menu
• Implemented
by
onCreateOp:onsMenu()
callback,
which
receives
an
instance
of
Menu
• Menu
can
be
structured
with
coding
or
using
XML
resource
(save
to
menu
folder)
• Use
XML
to
get
– easier
to
visualize
the
menu
structure
– separates
the
content
for
the
menu
from
your
applicaDon's
behavioral
code
– allows
you
to
create
alternaDve
menu
configuraDons
for
different
pla`orm
• Menu
selecDon
will
call
onOp:onsItemSelected(MenuItem)
funcDon
• Android
3.0
(API
level
11)
and
higher,
items
from
the
opDons
menu
can
be
available
in
the
acDons
bar
(android:showAsAcDon=“ifRoom”)
Android
Programming,
Pasi
Manninen.
74

75. Example:
OpDons
Menu
with
XML
<!–
res/menu/main.xml
-­‐-­‐>
<menu
xmlns:android="hTp://schemas.android.com/apk/res/android"
>
<item
android:id="@+id/acPon_video"
android:orderInCategory="100"
android:showAsAcDon="ifRoom"
android:icon="@drawable/video"
android:Dtle="@string/acPon_video"/>
<item
…
<item
android:id="@+id/acPon_quit"
android:orderInCategory="100"
android:showAsAcDon="never"
android:Dtle="@string/acPon_quit"/>
/*
Create
menu
items
*/
public
boolean
onCreateOpDonsMenu(Menu
menu)
{
//
load
menu
from
resources
MenuInflater
inflater
=
getMenuInflater();
inflater.inflate(R.menu.main,
menu);
return
true;
}
Android
Programming,
Pasi
Manninen.
75

76. Example:
OpDons
Menu
with
XML
• Use
Resource
Id’s
in
onOpDonsItemSelected()
/**
Handle
item
selecDons
*/
public
boolean
onOpDonsItemSelected(MenuItem
item)
{
switch
(item.getItemId())
{
case
R.id.ac:on_music:
Toast.makeText(getBaseContext(),
"Music",
Toast.LENGTH_SHORT).show();
return
true;
case
R.id.ac:on_video:
Toast.makeText(getBaseContext(),
“Video",
Toast.LENGTH_SHORT).show();
return
true;
case
R.id.ac:on_quit:
Toast.makeText(getBaseContext(),
"Quit",
Toast.LENGTH_SHORT).show();
return
true;
}
return
false;
}
Android
Programming,
Pasi
Manninen.
76

77. Contextual
Menus
• Offers
acDons
that
affect
a
specific
item
or
context
frame
in
the
UI
• OMen
used
with
List
or
Grid
Views
• Two
different
ways
to
use
– floaDng
context
menu
(list
of
menu
items
showed
when
user
performs
a
long
press),
one
selecDon
– contextual
acDon
mode
(Android
3.0
or
higher),
with
mulDple
selecDon
Android
Programming,
Pasi
Manninen.
77

78. Using
Context
Menu
• Override
the
AcDvity's
context
menu
callback
methods:
–
onCreateContextMenu(ContextMenu,View,Conte
xtMenuInfo)
– onContextItemSelected(MenuItem)
• Use
registerForContextMenu()
method
to
register
ContextMenu
to
View
• Menu
can
be
structured
with
coding
or
using
XML
resource
(save
to
menu
folder)
Android
Programming,
Pasi
Manninen.
78

79. Example:
Context
Menu
• Populate
ListView
with
ArrayAdapter
• AcDvity
should
extend
ListAcDvity
ListView
in
Layout
//
create
string
array
private
String
[]
items=
{"John
Koch","Peter
Michell","Ina
kudson”};
@Override
public
void
onCreate(Bundle
savedInstanceState)
{
setListAdapter(new
ArrayAdapter<String>
(
this,
android.R.layout.simple_list_item_1,
items));
//
register
contextMenu
for
this
ListAcDvity
registerForContextMenu(getListView());
}
Android
Programming,
Pasi
Manninen.
79

80. Example:
Context
Menu
• Context
Menu
menu
items
can
be
added
like
in
OpDons
Menu
(coding
or
XML)
Long
press
here
<?xml
version="1.0"
encoding="u/-­‐8"?>
<menu
…>
<item
android:id="@+id/acPon_call"
android:orderInCategory="100"
android:Dtle="@string/acPon_call"/>
<item
….
</menu>
@Override
public
void
onCreateContextMenu(ContextMenu
menu,
View
v,
ContextMenuInfo
menuInfo)
{
super.onCreateContextMenu(menu,
v,
menuInfo);
MenuInflater
inflater
=
getMenuInflater();
inflater.inflate(R.menu.context_menu,
menu);
}
Android
Programming,
Pasi
Manninen.
80

81. Example
Context
Menu
• Get
the
selecDon
with
onContextItemSelected
@Override
public
boolean
onContextItemSelected(MenuItem
item)
{
//
context
menu
item
AdapterContextMenuInfo
info
=
(AdapterContextMenuInfo)
item.getMenuInfo();
//
text
view
in
list
TextView
textView
=
(TextView)
info.targetView;
//
name
in
textview
String
name
=
textView.getText().toString();
//
acDon
switch
(item.getItemId())
{
case
R.id.acPon_call:
Toast.makeText(getBaseContext(),
"Call
to
"+name,
Toast.LENGTH_SHORT).show();
return
true;
...
Android
Programming,
Pasi
Manninen.
81

82. Using
Contextual
AcDon
Mode
• In
specific
view
– implement
AcDonMode.Callback
interface
• specify
acDons
with
XML
resource
(menu)
• respond
click
events
on
acDon
items
• handle
prepare
and
destroy
events
– call
startAcDonMode
to
show
the
acDon
• Example
in
source
codes
Android
Programming,
Pasi
Manninen.
82

83. Using
PopUp
Menu
• Define
menu
with
XML
• Call
PopUp
constructor
and
set
menu
item
click
listener
• Show
PopUp
menu
• Handle
selecDon
with
onMenuItemClick
• Example
in
source
codes
Note:
This
is
not
the
same
as
a
context
menu,
which
is
generally
for
acPons
that
affect
selected
content.
For
acPons
that
affect
selected
content,
use
the
contextual
acPon
mode
or
floaPng
context
menu.
Android
Programming,
Pasi
Manninen.
83

84. NoDfying
the
User
• It
is
good
to
noDfy
the
user
about
an
event
that
occurs
in
your
applicaDon
– Saving
a
file
is
complete
– ApplicaDon
is
running
in
the
background
and
needs
response
from
user
– ApplicaDon
is
performing
work
that
the
user
must
wait
for
• Android
offers
a
few
basic
techniques:
– Toast
NoDficaDon
– Using
NoDficaDon
Area
– Dialog
NoDficaDon
Android
Programming,
Pasi
Manninen.
84

85. NoDfying
the
user
with
Toast
• A
toast
noDficaDon
is
a
message
that
pops
up
on
the
window
• Fills
the
amount
of
space
required
for
the
message
• User's
current
acDvity
remains
visible
and
interac:ve
• NoDficaDon
automaDcally
fades
in
and
out
• Can
be
– fired
from
background
service
– posiDoned
differently
– customized
Android
Programming,
Pasi
Manninen.
85

86. Example:
Display
Toasts
//
get
applicaDon
context
Context
context
=
getApplicaDonContext();
//
toast
message
CharSequence
text
=
"Long
Toast";
//
duraDon
int
duraDon
=
Toast.LENGTH_SHORT;
//
create
toast
Toast
toast
=
Toast.makeText(context,text,duraPon);
//
show
toast
toast.show();
//
or
Toast.makeText(context,text,duraDon).show();
//
posiDon
top
leM
corner
toast.setGravity(Gravity.BOTTOM|Gravity.LEFT,
0,
0);
Android
Programming,
Pasi
Manninen.
86

87. Example:
Display
Custom
Toast
//
toast.xml
–
layout
file
<?xml
version="1.0"
encoding="UTF-­‐8"?>
<LinearLayout
…
android:id="@+id/toast”
…
>
<ImageView
android:id="@+id/image”
…
/>
<TextView
android:id="@+id/text”
…/>
</LinearLayout>
get
layout
from
AcDvity
//
• Make
layout
• Get
layout
from
AcDvity
• Set
Image
and
Text
• Show
toast
LayoutInflater
inflater
=
getLayoutInflater();
//
inflate
layout
from
XML
(toast.xml)
View
layout
=
inflater.inflate(R.layout.toast,
(ViewGroup)
findViewById(R.id.toast));
//
get
image
from
resource
ImageView
image
=
(ImageView)
layout.findViewById(R.id.image);
image.setImageResource(R.drawable.ptm);
//
set
text
TextView
text
=
(TextView)
layout.findViewById(R.id.text);
text.setText("This
is
a
custom
PTM
toast!");
//
create
and
show
toast
Toast
toast
=
new
Toast(getApplicaDonContext());
toast.setGravity(Gravity.CENTER_VERTICAL,
0,
0);
toast.setDuraDon(Toast.LENGTH_LONG);
toast.setView(layout);
toast.show();
Android
Programming,
Pasi
Manninen.
87

88. Using
NoDficaDon
Area
• Adds
an
icon
to
the
system's
status
bar
and
an
expanded
message
in
the
NoDficaDons
window
• Configurable:
alert
the
user
with
a
sound,
vibraDon
or
flashing
light
in
device
• Own
layout
can
be
used
like
in
Toast
NoDficaDons
• Ideal
when
applicaDon
is
working
in
a
background
Service
and
needs
to
no:fy
the
user
about
an
event
• When
the
user
selects
the
expanded
message,
Android
fires
an
Intent
that
is
defined
by
the
noDficaDon
(usually
to
launch
an
AcDvity)
• Design
guidelines
– h[p://developer.android.com/design/pa[erns/
noDficaDons.html
Android
Programming,
Pasi
Manninen.
88

89. Example:
NoDficaDon
Area
• Create
noDficaDon
from
a
Bu[on
• Open
AcDvity
from
noDficaDon
• Programming
– Use
NoDficaDonCombat.Builder
to
set
icon,
Dtle
and
text
of
noDficaDon
– Use
TaskStackBuilder
and
PendingIntent
to
start
AcDvity
when
user
clicks
noDficaDon
– Use
NoDficaDonManager
to
lauch
noDficaDon
Android
Programming,
Pasi
Manninen.
89

90. NoDfying
the
user
with
Dialogs
• Usually
appears
in
front
of
the
current
AcDvity
• Underlying
AcDvity
loses
focus
• Ask
user
to
make
a
decision
or
enter
addiDonal
informaDon
• How
to
– use
DialogFragment
as
a
container
of
your
dialog
– use
AlertDialog
as
a
style
and
structure
of
your
dialog
– use
DatePickerDialog
or
TimePickerDialog
in
special
case
– Dialog
class
is
base
class
behind
all
dialogs
• Design
guidelines
– h[p://developer.android.com/design/building-­‐blocks/
dialogs.html
Android
Programming,
Pasi
Manninen.
90

91. CreaDng
a
Dialog
• Extend
your
own
class
from
DialogFragment
• Create
for
example
AlertDialog
in
onCreateDialog()
method
• Create
instance
of
your
class
and
call
show()
method
• AlertDialog’s
bu[on
touches
will
automaDcally
dismiss
the
dialog
for
you
Android
Programming,
Pasi
Manninen.
91

92. Example:
AlertDialog
with
Bu[ons
• Three
regions
– Title,
Content
area
and
AcDon
bu[ons
public
class
ExitDialogFragment
extends
DialogFragment
{
@Override
public
Dialog
onCreateDialog(Bundle
savedInstanceState)
{
AlertDialog.Builder
builder
=
new
AlertDialog.Builder(getAcDvity());
builder.setTitle(R.string.dialog_Ptle)
.setMessage(R.string.dialog_exit)
.setPosiDveBu[on(R.string.dialog_yes,
new
DialogInterface.OnClickListener()
{
public
void
onClick(DialogInterface
dialog,
int
id)
{
//
Close
applicaDon
}
})
.setNegaDveBu[on(R.string.dialog_cancel,
new
DialogInterface.OnClickListener()
{
public
void
onClick(DialogInterface
dialog,
int
id)
{
//
User
cancelled
the
dialog
}
});
//
Create
the
AlertDialog
object
and
return
it
return
builder.create();
}
public
void
exitDialog(View
view)
{
}
ExitDialogFragment
eDialog
=
new
ExitDialogFragment();
eDialog.show(getFragmentManager(),
"exit");
}
Android
Programming,
Pasi
Manninen.
92

93. Example:
AlertDialog
with
List
• Create
list
in
String
resources
public
class
ListDialogFragment
extends
DialogFragment
{
@Override
public
Dialog
onCreateDialog(Bundle
savedInstanceState)
{
AlertDialog.Builder
builder
=
new
AlertDialog.Builder(getAcDvity());
builder.setTitle(R.string.listdialog_Dtle)
.setItems(R.array.messagetypes,
new
DialogInterface.OnClickListener()
{
public
void
onClick(DialogInterface
dialog,
int
index)
{
Resources
res
=
getResources();
String[]
messageTypes
=
res.getStringArray(R.array.messagetypes);
Toast.makeText(getAcDvity(),
"Selected
messageType
=
"
+
messageTypes[index],
Toast.LENGTH_SHORT).show();
}
});
return
builder.create();
}
}
Android
Programming,
Pasi
Manninen.
93

94. Custom
Dialog
Layouts
• Create
your
own
layout
for
the
dialog
window
with
layout
and
widget
elements
• Add
layout
to
AlertDialog
with
setView()
method
• Custom
layout
fills
the
dialog,
use
AlertDialog.builder
to
add
bu[ons
• Note
– Normal
AcDvity
can
be
used
as
a
Dialog
also
<acDvity
android:theme="@android:style/Theme.Holo.Dialog"
>
Android
Programming,
Pasi
Manninen.
94

95. Example:
Custom
Dialog
public
class
TeamDialogFragment
extends
DialogFragment
{
@Override
public
Dialog
onCreateDialog(Bundle
savedInstanceState)
{
AlertDialog.Builder
builder
=
new
AlertDialog.Builder(getAcDvity());
//
get
the
layout
inflater
LayoutInflater
inflater
=
getAcDvity().getLayoutInflater();
//
Inflate
and
set
the
layout
for
the
dialog
builder.setView(inflater.inflate(R.layout.add_team_dialog,
null))
.setTitle("Add
a
new
Team")
.setPosiDveBu[on("Add",
new
DialogInterface.OnClickListener()
{
@Override
public
void
onClick(DialogInterface
dialog,
int
id)
{
//
Add
a
team…
}
})
.setNegaDveBu[on("Cancel",
new
DialogInterface.OnClickListener()
{
public
void
onClick(DialogInterface
dialog,
int
id)
{
}
});
return
builder.create();
}
}
//
add_team_dialog.xml
<RelaDveLayout…
<TextView…
<EditText…
Android
Programming,
Pasi
Manninen.
95

96. Passing
events
back
to
dialog’s
host
• Dialog
might
perform
the
necessary
acDon
itself
(oMen
you
want
to
send
informaDon
back
to
the
AcDvity
which
opened
the
dialog)
– Define
an
interface
with
a
method
for
each
type
of
click
event
– Implement
interface
in
the
host
component
that
will
receive
the
acDon
events
from
the
dialog
– Override
DialogFrament’s
onA[ach()-­‐
method
to
instanDate
your
listener
(send
events
to
host)
//
look
DialogsExample
in
CustomDialog
project
(Custom
Dialog,
Add
a
new
Team)
Android
Programming,
Pasi
Manninen.
96

97. ProgressDialog
• ProgressDialog
is
an
extension
of
AlertDialog
class
• Use
in
following
cases:
– display
a
progress
animaDon
(a
spinning
wheel
or
a
progress
bar)
• ProgressDialog
can
also
provide
bu[ons,
such
as
one
to
cancel
a
download
• To
show
ProgressDialog
call
simply
ProgressDialog.show()
Note!
– Android
Progress
&
AcDvity
guidelines
says
”avoid”
for
ProgressDialog
use
– You
should
use
ProgressBar
instead
(inside
your
acDvity)
Android
Programming,
Pasi
Manninen.
97

98. ProgressBar
and
Indicators
• Use
Progress
bars
and
acDvity
indicators
to
signal
to
users
that
something
is
happening
• A
progress
bar
should
always
fill
from
0%
to
100%
and
never
move
backwards
to
a
lower
value
• Design
guidelines:
– h[p://developer.android.com/design/building-­‐
blocks/progress.html
Android
Programming,
Pasi
Manninen.
98

99. Example:
ProgressBar
• Sample
layout
with
ProgressBar
• Show
also
systems
ProgressBar
(circle)
• Simulate
loading
with
Thread
@Override
protected
void
onCreate(Bundle
savedInstanceState)
{
super.onCreate(savedInstanceState);
//
acDvate
indeterminate
progress
getWindow().requestFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
//
set
layout
for
the
acDvity
setContentView(R.layout.acDvity_main);
//
get
progressbar
progressBar
=
(ProgressBar)
findViewById(R.id.progressBar1);
}
//
start
"loading...”
public
void
startBu[onPressed(View
view)
{
MainAcDvity.this.setProgressBarIndeterminateVisibility(true);
startLoading();
}
Android
Programming,
Pasi
Manninen.
99

100. 8.
Understanding
of
the
Intents
• Intents
• Intent
Object
– AcDons,
Data,
Category,
Extras
•
•
•
•
•
•
•
•
•
Intent
ResoluDon,
Filters,
Matching
Intent
AcDons,
Data
and
Category
test
Example:
Intent
Filters
in
Manifest
Using
Explicit
Intent
to
start
a
new
AcDvity
Data
transfer
between
AcDviDes
ExpecDng
a
result
from
an
AcDvity
Using
Implicit
Intents
Custom
and
Broadcast
Intents
with
Receivers
Examples
and
Exercises
with
AcDviDes
and
Intents
Android
Programming,
Pasi
Manninen.
100

101. Intents
• The
most
unique
and
important
concept
in
Android
Development
• Intent
can
be
used
to
– broadcast
data
between
applicaDons
and
applicaDon
components
– start
AcDviDes
and
Services
– broadcast
that
an
event
or
acDon
has
occured
• Intent
is
like
a
”message”
to
someone
Android
Programming,
Pasi
Manninen.
101

102. Intent
Object
• An
Intent
object
is
a
bundle
of
informaDon
• Object
contains:
– Component,
specifies
an
explicit
name
of
a
component
class
to
use
for
the
intent
– Ac:on,
acDon
to
be
performed
(Androids
own
or
your
own
defined)
– Data,
the
URI
of
the
data
to
be
acted
on
and
the
MIME
type
of
that
data
– Category,
a
string
containing
addiDonal
informaDon
about
the
kind
of
component
that
should
handle
the
intent
– Type,
specifies
an
explicit
type
(a
MIME
type)
of
the
intent
data
– Extras,
key-­‐value
pairs
for
addiDonal
informaDon
that
should
be
delivered
to
the
component
handling
the
intent
– Flags,
instruct
the
Android
system
how
to
launch
an
acDvity
and
how
to
treat
it
Android
Programming,
Pasi
Manninen.
102

103. Intent
Object
AcDons
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
ACTION_MAIN
ACTION_VIEW
ACTION_ATTACH_DATA
ACTION_EDIT
ACTION_PICK
ACTION_CHOOSER
ACTION_GET_CONTENT
ACTION_DIAL
ACTION_CALL
ACTION_SEND
ACTION_SENDTO
ACTION_ANSWER
ACTION_INSERT
ACTION_DELETE
ACTION_RUN
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
ACTION_TIME_TICK
ACTION_TIME_CHANGED
ACTION_TIMEZONE_CHANGED
ACTION_BOOT_COMPLETED
ACTION_PACKAGE_ADDED
ACTION_PACKAGE_CHANGED
ACTION_PACKAGE_REMOVED
ACTION_PACKAGE_RESTARTED
ACTION_SYNC
ACTION_PICK_ACTIVITY
ACTION_SEARCH
ACTION_WEB_SEARCH
ACTION_FACTORY_TEST
…
fi.ptm.project.SHOW_COLOR
Android
Programming,
Pasi
Manninen.
103

104. Intent
Object
Data
• Some
examples
of
acDon/data
pairs
– ACTION_VIEW
content://contacts/people/1
– ACTION_DIAL
content://contacts/people/1
– ACTION_VIEW
tel:123
– ACTION_DIAL
tel:123
– ACTION_EDIT
content://contacts/people/1
– ACTION_VIEW
content://contacts/people/
Android
Programming,
Pasi
Manninen.
104

105. Intent
Object
Category
• Any
number
of
category
descripDons
can
be
placed
in
an
Intent
object
• Gives
addiDonal
informaDon
about
the
acDon
to
execute
•
•
•
•
•
•
•
CATEGORY_DEFAULT
CATEGORY_BROWSABLE
CATEGORY_TAB
CATEGORY_ALTERNATIVE
CATEGORY_SELECTED_ALTERNATIVE
CATEGORY_LAUNCHER
CATEGORY_INFO
•
•
•
•
•
•
•
CATEGORY_HOME
CATEGORY_PREFERENCE
CATEGORY_TEST
CATEGORY_CAR_DOCK
CATEGORY_DESK_DOCK
CATEGORY_CAR_MODE
…
Android
Programming,
Pasi
Manninen.
105

106. Intent
Object
Extras
• Extras
is
a
Bundle
of
any
addiDonal
informaDon
• Used
to
provide
extended
informaDon
to
the
component
Intent
intent
=
new
Intent(Intent.ACTION_SENDTO);
intent.setData(Uri.parse("sms://"));
intent.putExtra("address",
"04012345678");
intent.putExtra("sms_body",
"Your
message
here");
startAcDvity(intent);
Android
Programming,
Pasi
Manninen.
106

107. Intent
ResoluDon
• Intents
can
be
divided
into
two
groups
– Explicit
intents,
are
typically
used
for
applicaDon-­‐internal
messages
(between
AcDviDes)
– Implicit
intents,
are
oMen
used
to
acDvate
components
in
other
applicaDons
• Android
delivers
an
explicit
intent
to
an
instance
of
the
designated
target
class
• Implicit
intents
are
resolved
by
Intent
Filters
by
Intent
object’s
AcDon,
Data
and
Category
• In
implicit
intents,
Android
system
must
find
the
best
component
(or
components)
to
handle
the
intent
Android
Programming,
Pasi
Manninen.
107

108. Intent
Filters
• An
explicit
intent
is
always
delivered
to
its
target,
no
ma[er
what
it
contains
• AcDviDes,
services,
and
broadcast
receivers
can
have
one
or
more
intent
filters
• Each
filter
describes
a
capability
of
the
component,
a
set
of
intents
that
the
component
is
willing
to
receive
• Component
has
separate
filters
for
each
job
it
can
do
• Intent
Filters
are
set
up
in
the
applica:on's
manifest
file
(AndroidManifest.xml)
as
<intent-­‐filter>
elements
• An
implicit
intent
is
tested
against
acDon,
data
and
category
fields
in
manifest
Android
Programming,
Pasi
Manninen.
108

109. Intent
Matching
• Intents
are
matched
against
intent
filters
not
only
to
discover
a
target
component
to
acDvate,
but
also
to
discover
something
about
the
set
of
components
on
the
device
• Examples:
•
AcDvity
is
shown
in
applicaDon
launcher
(”menu
in
screen”)
– android.intent.acDon.MAIN
– android.intent.category.LAUNCHER"
• AcDvity
handles
widgets
Update
(Dme
based)
and
two
own
“Receiver”
and
“Reload”
Intents
– android.appwidget.acDon.APPWIDGET_UPDATE
– fi.ptm.namedays.ACTION_WIDGET_RECEIVER
– fi.ptm.namedays.ACTION_WIDGER_RELOAD
Android
Programming,
Pasi
Manninen.
109

110. Intent
Filters
–
AcDon
Test
• To
pass
this
test,
the
Intent
object
must
match
one
of
the
acDons
listed
in
the
filter
(in
manifest)
• An
Intent
object
that
doesn't
specify
an
acDon
automaDcally
passes
the
acDon
test,
as
long
as
the
filter
contains
at
least
one
acDon
• Intent
filter
must
contain
at
least
one
acDon
element
<intent-­‐filter
.
.
.
>
<acDon
android:name="com.example.project.SHOW_CURRENT"
/>
<acDon
android:name="com.example.project.SHOW_RECENT"
/>
<acDon
android:name="com.example.project.SHOW_PENDING"
/>
.
.
.
</intent-­‐filter>
Android
Programming,
Pasi
Manninen.
110

111. Intent
Filters
–
Category
Test
• To
pass
the
category
test,
every
category
in
the
Intent
object
must
match
a
category
in
the
filter
• AddiDonal
categories
can
be
listed,
but
it
cannot
omit
any
that
are
in
the
intent
<intent-­‐filter
.
.
.
>
.
.
.
<category
android:name="android.intent.category.DEFAULT"
/>
<category
android:name="android.intent.category.BROWSABLE"
/>
.
.
.
</intent-­‐filter>
Android
Programming,
Pasi
Manninen.
111

112. Intent
Filters
–
Data
test
• Like
the
acDon
and
categories,
the
data
specificaDon
for
an
intent
filter
is
contained
in
a
subelement,
it
can
appear
mulDple
Dmes,
or
not
at
all
• Each
<data>
element
can
specify
a
URI
and
a
data
type
(MIME
media
type)
• When
the
URI
in
an
Intent
object
is
compared
to
a
URI
specificaDon
in
a
filter,
it's
compared
only
to
the
parts
of
the
URI
actually
menDoned
in
the
filter
<intent-­‐filter>
<acDon
android:name="android.intent.acDon.VIEW"
/>
<category
android:name="android.intent.category.DEFAULT"
/>
<category
android:name="android.intent.category.BROWSABLE"
/>
<data
android:scheme="h[p"
/>
<data
android:mimeType="audio/mp3"/>
<data
android:mimeType="audio/mp4"/>
...
Android
Programming,
Pasi
Manninen.
112

113. Example:
Intent
Filters
in
Manifest
<?xml
version="1.0"
encoding="u/-­‐8"?>
<manifest
…>
<applicaDon
...>
<acDvity
android:name=".MainAcPvity“
MainAcDvity
can
be
lauched
from
the
android:label="@string/app_name">
menu
and
it
can
also
handle
intent
that
<intent-­‐filter>
is
describe
below.
<!–
start
as
main
entry
point
-­‐-­‐>
<acDon
android:name="android.intent.acPon.MAIN"
/>
<category
android:name="android.intent.category.LAUNCHER"
/>
</intent-­‐filter>
<intent-­‐filter>
<acDon
android:name="fi.ptm.PLAY_SOUND"
/>
<data
android:mimeType="audio/mp3"
android:scheme="hTp"/>
<category
android:name="android.intent.category.DEFAULT"
/>
</intent-­‐filter>
</applicaDon>
</manifest>
Intent
intent
=
new
Intent(”fi.ptm.PLAY_SOUND”,
Uri.parse(”h[p://somedomain.com/music.mp3”));
startAcDvity(intent);
Android
Programming,
Pasi
Manninen.
113

114. Using
explicit
Intent
to
start
a
new
AcDvity
• startAcDvity(intent)
– starts
a
new
AcDvity
– it
is
possible
to
send
data
to
with
intent
– acDvity
will
not
be
informed
when
the
child
acDvity
is
complete
• startAcDvityForResult(intent,
REQUEST_CODE)
– like
previous,
but
it
takes
unique
constant
– acDvity
will
be
noDfied
when
the
child
acDvity
is
complete
via
the
onAcDvityResult()
callback
Android
Programming,
Pasi
Manninen.
114