Using View Flipper in Android

Suppose you want to display a news bar in your activity. this news bar displays a single news item at a time then flips and shows next item and so on, then your choice would be Androids ViewFlipper.

ViewFlipper inherits from frame layout, so it displays a single view at a time.

consider this layout:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 
 android_orientation="vertical"
 android_layout_width="fill_parent"
 android_layout_height="fill_parent"
 >
<TextView 
 android_layout_width="fill_parent" 
 android_layout_height="wrap_content" 
 android_text="@string/hello"
 />
 <Button
 android_layout_width="wrap_content" 
 android_layout_height="wrap_content" 
 android_text="Flip"
 android_id="@+id/btn"
 android_onClick="ClickHandler"
 />
 <ViewFlipper
 android_layout_width="fill_parent" 
 android_layout_height="fill_parent"
 android_id="@+id/flip"
 >
 <TextView 
 android_layout_width="fill_parent" 
 android_layout_height="wrap_content" 
 android_text="Item1"
 />
 <TextView 
 android_layout_width="fill_parent" 
 android_layout_height="wrap_content" 
 android_text="Item2"
 />
 <TextView 
 android_layout_width="fill_parent" 
 android_layout_height="wrap_content" 
 android_text="Item3"
 />
 </ViewFlipper>
</LinearLayout>

just a ViewFlipper container that contains three text views

now we want to flip the views when the button is clicked

public void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.main);
 
 btn=(Button)findViewById(R.id.btn);
 flip=(ViewFlipper)findViewById(R.id.flip);
 
 }
 
 public void ClickHandler(View v)
 {
 
 flip.showNext();
 
 }

if we want to flip in reverese direction we could use
flip.showPrevious() instead

we can add animations to the child views when they appear or disappear:

@Override
 public void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.main);
 
 btn=(Button)findViewById(R.id.btn);
 flip=(ViewFlipper)findViewById(R.id.flip);
 //when a view is displayed
 flip.setInAnimation(this,android.R.anim.fade_in);
 //when a view disappears
 flip.setOutAnimation(this, android.R.anim.fade_out); 
 }

we can also set the ViewFlipper to flip views automatically when the button is clicked:

public void ClickHandler(View v)
 {
 
 
 //specify flipping interval
 flip.setFlipInterval(1000);
 flip.startFlipping();
 }

we can stop the flipping by calling flip.stopFlipping(); method.

or we can set the flipper to flip autommatically when the activity starts

public void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.main);
 
 btn=(Button)findViewById(R.id.btn);
 flip=(ViewFlipper)findViewById(R.id.flip);
 flip.setInAnimation(this,android.R.anim.fade_in);
 flip.setOutAnimation(this, android.R.anim.fade_out);
 flip.setFlipInterval(1000);
 flip.setAutoStart(true);
 
 }

Related Posts by Categories