1.
Mobile
Software
Engineering
L04 – Android Cont.
Mohammad Shaker
FIT of Damascus - AI dept.
MohammadShakerGtr@gmail.com
Mobile SE – August 2012

2.
Activities
Starting Another Activity

3.
Intent
an object that provides runtime binding between separate
components (such as two activities)

4.
Intent
carry a collection of various data types as key-value pairs
called extras through putExtra()

5.
It’s a good practice..
to define keys for intent extras using your app's package name as a prefix.
This ensures they are unique, in case your app interacts with other apps.

6.
Starting Another Activity
http://developer.android.com/training/basics/firstapp/starting-activity.html#BuildIntent
Project Attached

7.
Starting Another Activity
public final static String EXTRA_MESSAGE =
"com.example.intetsample.MESSAGE";
public void sendMessage(View view) {
Intent intent = new Intent(this, DisplayMessageActivity.class);
EditText editText = (EditText) findViewById(R.id.editText1);
String message = editText.getText().toString();
intent.putExtra(EXTRA_MESSAGE, message);
startActivity(intent);
}

8.
AndroidManifest.xml

9.
AndroidManifest.xml
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/title_activity_main" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".DisplayMessageActivity"
android:label="@string/title_activity_display_message" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.example.intetsample.MainActivity" />
</activity>
</application>

10.
Managing the Activity
Life Cycle

11.
Destroy the activity
onDestroy()

12.
Destroy the activity

13.
onPasue()
@Override
public void onPause() {
// Always call the superclass method first
super.onPause();
// Release the Camera because
// we don't need it when paused
// and other activities might need to use it.
if (mCamera != null) {
mCamera.release()
mCamera = null;
}
}

14.
onResume()
@Override
public void onResume() {
// Always call the superclass method first
super.onResume();
// Get the Camera instance as the activity
// achieves full user focus
if (mCamera == null) {
// Local method to handle camera init
initializeCamera(); }
}

15.
Recreating activity
onSaveInstanceState

16.
Storage – Database
Sqlite3

17.
Draggable stick
project sample attached

18.
OpenGL ES

19.
How can we animate?

20.
'Must Override a Superclass
Method' Errors after importing a
project into Eclipse Problem
http://stackoverflow.com/questions/1678122/must-override-a-superclass-
method-errors-after-importing-a-project-into-eclips

21.
@Override
public boolean onTouchEvent(MotionEvent e) {
float x = e.getX(); float y = e.getY();
switch (e.getAction()) {
case MotionEvent.ACTION_MOVE:
float dx = x - mPreviousX; float dy = y - mPreviousY;
// reverse direction of rotation above the mid-line
if (y > getHeight() / 2) { dx = dx * -1 ; }
// reverse direction of rotation to left of the mid-line
if (x < getWidth() / 2) { dy = dy * -1 ; }
mRenderer.mAngle += (dx + dy) * TOUCH_SCALE_FACTOR;
// = 180.0f / 320
requestRender();
}
mPreviousX = x; mPreviousY = y;
return true;
}

22.
Let’s get our hands dirty
with code!

23.
Advanced Training
• Making Your App Location Aware
• Performing Network Operations
• Transferring Data Without Draining the Battery
• Syncing to the Cloud
• Designing for Multiple Screens
• Improving Layout Performance
• Managing Audio Playback
• Optimizing Battery Life
• Creating Custom Views
• Adding Search Functionality
• Remembering Users
• Sharing Content
• Capturing Photos
• Maintaining Multiple APKs
• Creating Backward-Compatible UIs
• Developing for Enterprise
• Monetizing Your App
• Designing Effective Navigation
• Implementing Effective Navigation
• Designing for TV
• Displaying Bitmaps Efficiently
• Implementing Accessibility
• Displaying Graphics with OpenGL ES

24.
See you nxt time!