Example for Activity Life Cycle/Introdution to Activities in Android

Activity Life Cycle/Activity life cycle example in android

• An activity represents a single screen with a user interface
• A users can interact in order to do something, such as dial the phone, take a photo, send an email, or view a map
• An activity is implemented as a subclass of Activity
• An application usually consists of multiple activities that are loosely bound to each other

Example for Activity LifeCycle
LifeCycleActivity .java



 

public class LifeCycleActivity extends Activity {  

   /** Called when the activity is first created. */

    @Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

Toast.makeText(this, "onCreate()", Toast.L E N  G TH_LO N   G ).show();

}

@Override

protected void onStart() {

//the activity is become visible.

super.onStart();

Toast.makeText(this, "onStart()", Toast.L E N  G TH_LO N   G ).show();

}

@Override

protected void on P ause() {

super.onPause();

Toast.makeText(this, "on P ause()", Toast.L E N  G TH_LO N   G ).show();

}

@Override

protected void onResume() {

// TODO  Auto-generated method stub

super .onResume();

Toast.makeText(this,” onResume() ” , Toast.LENGTH_LONG).show();

}

@Override

protected void onStop() {

//the activity is no longer visible.

super.onStop();

Toast.makeText(this, "onStop()", Toast.L E NGTH_LONG).show();

}

@Override

protected void onDestroy() {

//The activity about to be destroyed.

super.onDestroy();

Toast.makeText(this, "onDestroy()", Toast.L E NGTH_LONG).show();

}

}

 main.xml

<?xml version= “  1 . 0   "  encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"     android:orientation="v  e r tical"     android:layout_width="fi Ll     _parent"     android:layout_height="fill_parent"     > <TextView      android:layout_width="fill_parent"     android:layout_height="wrap_content"     android:text="@string/hello"     /> <Button android:text="button" android:id="@+id/button1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:clickable="true" android:onclick="select"> </Button> </LinearLayout>