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Detect Gesture by implementing GestureDetector.SimpleOnGestureListener

This example show how to detect user gesture by implementing GestureDetector.SimpleOnGestureListener. It have the same result as last exercise of "GestureDetector".

GestureDetector.SimpleOnGestureListener provides an implementation for all of the on<TouchEvent> methods by returning false for all of them. Thus we can override only the methods we care about. In our application, we have to detect onFling() only. So we can extend GestureDetector.SimpleOnGestureListener instead of implementing the GestureDetector.OnGestureListener interface.

MainActivity.java

package com.example.androidviewflipper;

import android.os.Bundle;
import android.app.Activity;
import android.support.v4.view.GestureDetectorCompat;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.Toast;
import android.widget.ViewFlipper;

public class MainActivity extends Activity{
 
 private GestureDetectorCompat mDetector;

 Button buttonPrev, buttonNext;
 ViewFlipper viewFlipper;

 Animation slide_in_left, slide_out_right;
 Animation slide_in_right, slide_out_left;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  
  mDetector = new GestureDetectorCompat(this, new MyGestureListener());

  buttonPrev = (Button) findViewById(R.id.prev);
  buttonNext = (Button) findViewById(R.id.next);
  viewFlipper = (ViewFlipper) findViewById(R.id.viewflipper);

  slide_in_left = AnimationUtils.loadAnimation(this,
    R.anim.slide_in_left);
  slide_out_right = AnimationUtils.loadAnimation(this,
    R.anim.slide_out_right);
  
  slide_in_right = AnimationUtils.loadAnimation(this,
    R.anim.slide_in_right);
  slide_out_left = AnimationUtils.loadAnimation(this,
    R.anim.slide_out_left);

  buttonPrev.setOnClickListener(new OnClickListener() {

   @Override
   public void onClick(View arg0) {
    viewFlipper.setInAnimation(slide_in_right);
    viewFlipper.setOutAnimation(slide_out_left);
    viewFlipper.showPrevious();
   }
  });

  buttonNext.setOnClickListener(new OnClickListener() {

   @Override
   public void onClick(View arg0) {
    viewFlipper.setInAnimation(slide_in_left);
    viewFlipper.setOutAnimation(slide_out_right);
    viewFlipper.showNext();
   }
  });
  ;
 }

 @Override
 public boolean onTouchEvent(MotionEvent event) {
  this.mDetector.onTouchEvent(event);
  return super.onTouchEvent(event);
 }

 class MyGestureListener extends GestureDetector.SimpleOnGestureListener {

  @Override
  public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
    float velocityY) {
   float sensitvity = 50;
   
   if((e1.getX() - e2.getX()) > sensitvity){
    viewFlipper.setInAnimation(slide_in_right);
    viewFlipper.setOutAnimation(slide_out_left);
    viewFlipper.showPrevious();
    Toast.makeText(MainActivity.this, 
      "Previous", Toast.LENGTH_SHORT).show();
   }else if((e2.getX() - e1.getX()) > sensitvity){
    viewFlipper.setInAnimation(slide_in_left);
    viewFlipper.setOutAnimation(slide_out_right);
    viewFlipper.showNext();
    Toast.makeText(MainActivity.this, 
      "Next", Toast.LENGTH_SHORT).show();
   }
   
   return true;
  }
    }
}

Keep using the layout and animation XML files in the exercise of "Bi-direction sliding ViewFlipper".

Download the files.

Using GestureDetector to detect user swipe, onFling()

Previous exercise demonstrate "Bi-direction sliding ViewFlipper" controlled by buttons. This exercise show how to implements GestureDetector.OnGestureListener to detect user swipe to update ViewFlipper.

package com.example.androidviewflipper;

import android.os.Bundle;
import android.app.Activity;
import android.support.v4.view.GestureDetectorCompat;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.Toast;
import android.widget.ViewFlipper;

public class MainActivity extends Activity implements 
 GestureDetector.OnGestureListener {
 
 private GestureDetectorCompat mDetector;

 Button buttonPrev, buttonNext;
 ViewFlipper viewFlipper;

 Animation slide_in_left, slide_out_right;
 Animation slide_in_right, slide_out_left;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  
  mDetector = new GestureDetectorCompat(this,this);

  buttonPrev = (Button) findViewById(R.id.prev);
  buttonNext = (Button) findViewById(R.id.next);
  viewFlipper = (ViewFlipper) findViewById(R.id.viewflipper);

  slide_in_left = AnimationUtils.loadAnimation(this,
    R.anim.slide_in_left);
  slide_out_right = AnimationUtils.loadAnimation(this,
    R.anim.slide_out_right);
  
  slide_in_right = AnimationUtils.loadAnimation(this,
    R.anim.slide_in_right);
  slide_out_left = AnimationUtils.loadAnimation(this,
    R.anim.slide_out_left);
  
  //viewFlipper.setInAnimation(slide_in_left);
  //viewFlipper.setOutAnimation(slide_out_right);

  buttonPrev.setOnClickListener(new OnClickListener() {

   @Override
   public void onClick(View arg0) {
    viewFlipper.setInAnimation(slide_in_right);
    viewFlipper.setOutAnimation(slide_out_left);
    viewFlipper.showPrevious();
   }
  });

  buttonNext.setOnClickListener(new OnClickListener() {

   @Override
   public void onClick(View arg0) {
    viewFlipper.setInAnimation(slide_in_left);
    viewFlipper.setOutAnimation(slide_out_right);
    viewFlipper.showNext();
   }
  });
  ;
 }

 @Override
 public boolean onTouchEvent(MotionEvent event) {
  this.mDetector.onTouchEvent(event);
  return super.onTouchEvent(event);
 }

 @Override
 public boolean onDown(MotionEvent arg0) {
  // TODO Auto-generated method stub
  return false;
 }

 @Override
 public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
   float velocityY) {
  float sensitvity = 50;
  
  if((e1.getX() - e2.getX()) > sensitvity){
   viewFlipper.setInAnimation(slide_in_right);
   viewFlipper.setOutAnimation(slide_out_left);
   viewFlipper.showPrevious();
   Toast.makeText(MainActivity.this, 
     "Previous", Toast.LENGTH_SHORT).show();
  }else if((e2.getX() - e1.getX()) > sensitvity){
   viewFlipper.setInAnimation(slide_in_left);
   viewFlipper.setOutAnimation(slide_out_right);
   viewFlipper.showNext();
   Toast.makeText(MainActivity.this, 
     "Next", Toast.LENGTH_SHORT).show();
  }
  
  return true;
 }

 @Override
 public void onLongPress(MotionEvent e) {
  // TODO Auto-generated method stub
  
 }

 @Override
 public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
   float distanceY) {
  // TODO Auto-generated method stub
  return false;
 }

 @Override
 public void onShowPress(MotionEvent e) {
  // TODO Auto-generated method stub
  
 }

 @Override
 public boolean onSingleTapUp(MotionEvent e) {
  // TODO Auto-generated method stub
  return false;
 }

}

Keep using the layout and animation XML files in last exercise.

Download the files.


Next:
- Detect Gesture by implementing GestureDetector.SimpleOnGestureListener

Download The Windows Getting Started Guide

This guide will point you to the right developer tools, tutorials, and resources. Jump in. The next generation is what you make it.

Download here.

and more resources on Microsoft Student web site.

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Publication Date: November 4, 2013 | ISBN-10: 1118717376 | ISBN-13: 978-1118717370 | Edition: 1

How to build Open JavaFX for Android

Here (https://blogs.oracle.com/jfxprg/entry/how_to_build_open_javafx) is a short recipe for baking JavaFX for Android dalvik. Just a few ingredients needed but each one requires special care.

Bi-direction sliding ViewFlipper

Last exercise show a Example of ViewFlipper. It always slide from left to right, no matter you click previous or next button. In this exercise, we will implement bi-direction sliding. Slide to right if you click next button, slide left if you click previous button. This technique can also be applied on ViewAnimator, TextSwitcher, ImageSwitcher and ViewSwitcher.

Create /res/anim/ folder, and create the following XMLs to define the animation.

slide_in_left.xml:

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
 <translate android:fromXDelta="-50%p" android:toXDelta="0"
            android:duration="1000"/>
 <alpha android:fromAlpha="0.0" android:toAlpha="1.0"
            android:duration="1000" />
</set>

slide_in_right.xml:

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
 <translate android:fromXDelta="50%p" android:toXDelta="0"
            android:duration="1000"/>
 <alpha android:fromAlpha="0.0" android:toAlpha="1.0"
            android:duration="1000" />
</set>

slide_out_left.xml:

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
 <translate android:fromXDelta="0" android:toXDelta="-50%p"
            android:duration="1000"/>
 <alpha android:fromAlpha="1.0" android:toAlpha="0.0"
            android:duration="1000" />
</set>

slide_out_right.xml:

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
 <translate android:fromXDelta="0" android:toXDelta="50%p"
            android:duration="1000"/>
 <alpha android:fromAlpha="1.0" android:toAlpha="0.0"
            android:duration="1000" />
</set>

Modify layout file, all child View of <ViewFlipper> have android:layout_width="match_parent".

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:autoLink="web"
        android:text="http://android-er.blogspot.com/"
        android:textStyle="bold" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal" >

        <Button
            android:id="@+id/prev"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="previous" />

        <Button
            android:id="@+id/next"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="next" />
    </LinearLayout>

    <ViewFlipper
        android:id="@+id/viewflipper"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <ImageView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:src="@drawable/ic_launcher" />

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >

            <Button
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="- Button 2 -" />

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="LinearLayout 2" />
        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >

            <EditText
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:hint="Enter something" />

            <TextView
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="LinearLayout 3" />
        </LinearLayout>

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="ViewFlipper is a simple ViewAnimator that 
     will animate between two or more views that 
     have been added to it. Only one child is shown 
     at a time. If requested, can automatically 
     flip between each child at a regular interval." />
    </ViewFlipper>

</LinearLayout>

Main code;

package com.example.androidviewflipper;

import android.os.Bundle;
import android.app.Activity;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.ViewFlipper;

public class MainActivity extends Activity {

 Button buttonPrev, buttonNext;
 ViewFlipper viewFlipper;

 Animation slide_in_left, slide_out_right;
 Animation slide_in_right, slide_out_left;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);

  buttonPrev = (Button) findViewById(R.id.prev);
  buttonNext = (Button) findViewById(R.id.next);
  viewFlipper = (ViewFlipper) findViewById(R.id.viewflipper);

  slide_in_left = AnimationUtils.loadAnimation(this,
    R.anim.slide_in_left);
  slide_out_right = AnimationUtils.loadAnimation(this,
    R.anim.slide_out_right);
  
  slide_in_right = AnimationUtils.loadAnimation(this,
    R.anim.slide_in_right);
  slide_out_left = AnimationUtils.loadAnimation(this,
    R.anim.slide_out_left);
  
  //viewFlipper.setInAnimation(slide_in_left);
  //viewFlipper.setOutAnimation(slide_out_right);

  buttonPrev.setOnClickListener(new OnClickListener() {

   @Override
   public void onClick(View arg0) {
    viewFlipper.setInAnimation(slide_in_right);
    viewFlipper.setOutAnimation(slide_out_left);
    viewFlipper.showPrevious();
   }
  });

  buttonNext.setOnClickListener(new OnClickListener() {

   @Override
   public void onClick(View arg0) {
    viewFlipper.setInAnimation(slide_in_left);
    viewFlipper.setOutAnimation(slide_out_right);
    viewFlipper.showNext();
   }
  });
  ;
 }

}

Next: Using GestureDetector to detect user swipe, onFling()

Example of ViewFlipper

android.widget.ViewFlipper is a simple ViewAnimator that will animate between two or more views that have been added to it. Only one child is shown at a time. If requested, can automatically flip between each child at a regular interval.

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:autoLink="web"
        android:text="http://android-er.blogspot.com/"
        android:textStyle="bold" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal" >

        <Button
            android:id="@+id/prev"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="previous" />

        <Button
            android:id="@+id/next"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="next" />
    </LinearLayout>

    <ViewFlipper
        android:id="@+id/viewflipper"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/ic_launcher" />

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >

            <Button
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="- Button 2 -" />

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="LinearLayout 2" />
        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >

            <EditText
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:hint="Enter something" />

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="LinearLayout 3" />
        </LinearLayout>

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="ViewFlipper is a simple ViewAnimator that 
     will animate between two or more views that 
     have been added to it. Only one child is shown 
     at a time. If requested, can automatically 
     flip between each child at a regular interval." />
    </ViewFlipper>

</LinearLayout>

package com.example.androidviewflipper;

import android.os.Bundle;
import android.app.Activity;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.ViewFlipper;

public class MainActivity extends Activity {

 Button buttonPrev, buttonNext;
 ViewFlipper viewFlipper;

 Animation slide_in_left, slide_out_right;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);

  buttonPrev = (Button) findViewById(R.id.prev);
  buttonNext = (Button) findViewById(R.id.next);
  viewFlipper = (ViewFlipper) findViewById(R.id.viewflipper);

  slide_in_left = AnimationUtils.loadAnimation(this,
    android.R.anim.slide_in_left);
  slide_out_right = AnimationUtils.loadAnimation(this,
    android.R.anim.slide_out_right);

  viewFlipper.setInAnimation(slide_in_left);
  viewFlipper.setOutAnimation(slide_out_right);

  buttonPrev.setOnClickListener(new OnClickListener() {

   @Override
   public void onClick(View arg0) {
    viewFlipper.showPrevious();
   }
  });

  buttonNext.setOnClickListener(new OnClickListener() {

   @Override
   public void onClick(View arg0) {
    viewFlipper.showNext();
   }
  });
  ;
 }

}

assets folder in Android Studio

Android Studio is a new Android development environment based on IntelliJ IDEA, Gradle-based build support. It have different project structure.

In Eclipse, assets is in /assets folder under your project. In Android Studio, it is in /src/main/assets. In both Eclipse and Android Studio, /assets have the same level of /res folder.

Compare with the exercise of "Embed html using Google Maps JavaScript API v3 in Android App", where /assets/simplemap.html is a asset file of HTML. In Android Studio, it in /src/main/assets/simplemap.html. In both case, it can be accessed with "file:///android_asset/simplemap.html".

reference: Gradle Plugin User Guide > Project Structure

Example of ViewSwitcher

android.widget.ViewSwitcher is a sub-class of ViewAnimator, switches between two views, and has a factory from which these views are created. You can either use the factory to create the views, or add them yourself.

A ViewSwitcher can only have two child views, of which only one is shown at a time. If you have more than two child views in ViewSwitch, java.lang.IllegalStateException of "Can't add more than 2 views to a ViewSwitcher" will happen.

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:autoLink="web"
        android:text="http://android-er.blogspot.com/"
        android:textStyle="bold" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal" >

        <Button
            android:id="@+id/prev"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="previous" />

        <Button
            android:id="@+id/next"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="next" />
    </LinearLayout>

    <ViewSwitcher
        android:id="@+id/viewswitcher"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/ic_launcher" />

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >

            <Button
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="- Button 2 -" />

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="LinearLayout 2" />
        </LinearLayout>
    </ViewSwitcher>

</LinearLayout>

package com.example.androidviewswitcher;

import android.os.Bundle;
import android.app.Activity;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.ViewSwitcher;

public class MainActivity extends Activity {

 Button buttonPrev, buttonNext;
 ViewSwitcher viewSwitcher;

 Animation slide_in_left, slide_out_right;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);

  buttonPrev = (Button) findViewById(R.id.prev);
  buttonNext = (Button) findViewById(R.id.next);
  viewSwitcher = (ViewSwitcher) findViewById(R.id.viewswitcher);

  slide_in_left = AnimationUtils.loadAnimation(this,
    android.R.anim.slide_in_left);
  slide_out_right = AnimationUtils.loadAnimation(this,
    android.R.anim.slide_out_right);

  viewSwitcher.setInAnimation(slide_in_left);
  viewSwitcher.setOutAnimation(slide_out_right);

  buttonPrev.setOnClickListener(new OnClickListener() {

   @Override
   public void onClick(View arg0) {
    viewSwitcher.showPrevious();
   }
  });

  buttonNext.setOnClickListener(new OnClickListener() {

   @Override
   public void onClick(View arg0) {
    viewSwitcher.showNext();
   }
  });
  ;
 }

}

- Compare with ViewAnimator

Good official lessons teach Caching Bitmaps and Managing Bitmap Memory

When your app have to load a number of bitmap, memory allocation will get complicated. Here is official lessons from developer.android.com.

• Caching Bitmaps teach you using a memory and disk bitmap cache to improve the responsiveness and fluidity of your UI when loading multiple bitmaps.
• Managing Bitmap Memory teach specific things you can do to facilitate garbage collection and bitmap reuse.

Also, the video Bitmap Allocation by DevBytes introduce how to speed up bitmap loading and reduce garbage collection by reusing existing bitmaps.

Android example: ImageSwitcher

A simple example to implement ImageSwitcher.

package com.example.androidimageswitcher;

import android.os.Bundle;
import android.app.Activity;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup.LayoutParams;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.ImageSwitcher;
import android.widget.ImageView;
import android.widget.ViewSwitcher.ViewFactory;

public class MainActivity extends Activity {

 Button buttonNext;
 ImageSwitcher imageSwitcher;

 Animation slide_in_left, slide_out_right;

 int imageResources[] = { 
   android.R.drawable.ic_dialog_alert,
   android.R.drawable.ic_dialog_dialer,
   android.R.drawable.ic_dialog_email,
   android.R.drawable.ic_dialog_info, 
   android.R.drawable.ic_dialog_map };

 int curIndex;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);

  buttonNext = (Button) findViewById(R.id.next);
  imageSwitcher = (ImageSwitcher) findViewById(R.id.imageswitcher);

  slide_in_left = AnimationUtils.loadAnimation(this,
    android.R.anim.slide_in_left);
  slide_out_right = AnimationUtils.loadAnimation(this,
    android.R.anim.slide_out_right);

  imageSwitcher.setInAnimation(slide_in_left);
  imageSwitcher.setOutAnimation(slide_out_right);

  imageSwitcher.setFactory(new ViewFactory() {

   @Override
   public View makeView() {

    ImageView imageView = new ImageView(MainActivity.this);
    imageView.setScaleType(ImageView.ScaleType.FIT_CENTER);

    LayoutParams params = new ImageSwitcher.LayoutParams(
      LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);

    imageView.setLayoutParams(params);
    return imageView;

   }
  });

  curIndex = 0;
  imageSwitcher.setImageResource(imageResources[curIndex]);

  buttonNext.setOnClickListener(new OnClickListener() {

   @Override
   public void onClick(View arg0) {
    if (curIndex == imageResources.length - 1) {
     curIndex = 0;
     imageSwitcher.setImageResource(imageResources[curIndex]);
    } else {
     imageSwitcher.setImageResource(imageResources[++curIndex]);
    }
   }
  });
 }

}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:autoLink="web"
        android:text="http://android-er.blogspot.com/"
        android:textStyle="bold" />

    <ImageSwitcher
        android:id="@+id/imageswitcher"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal" />

    <Button
        android:id="@+id/next"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="next" />

</LinearLayout>

ListFragment with multiple choice

It is a example to implement ListFragment with multiple choice.

Base on my old exercise of "ListFragment".

Modify MyListFragment1.java, create ListAdapter with android.R.layout.simple_list_item_multiple_choice. Also modify onListItemClick() to display the clicked item and selected items.

package com.exercise.AndroidListFragment;

import android.app.ListFragment;
import android.os.Bundle;
import android.util.SparseBooleanArray;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.Toast;

public class MyListFragment1 extends ListFragment {

 String[] month ={
   "January", 
   "February", 
   "March", 
   "April",
   "May", 
   "June", 
   "July", 
   "August",
   "September", 
   "October", 
   "November", 
   "December"
 };

 @Override
 public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);

  ListAdapter myListAdapter = new ArrayAdapter<String>(
    getActivity(),
    android.R.layout.simple_list_item_multiple_choice,
    month);
  
  setListAdapter(myListAdapter);
 }

 @Override
 public View onCreateView(LayoutInflater inflater, ViewGroup container,
   Bundle savedInstanceState) {
  return inflater.inflate(R.layout.listfragment1, container, false);
  
 }

 @Override
 public void onListItemClick(ListView l, View v, int position, long id) {
  
  String prompt = 
    "clicked item: " + getListView().getItemAtPosition(position).toString() + "\n\n";
  
  prompt += "selected items: \n";
  int count = getListView().getCount();
  SparseBooleanArray sparseBooleanArray = getListView().getCheckedItemPositions();
  for (int i = 0; i < count; i++){
   if (sparseBooleanArray.get(i)) {
    prompt += getListView().getItemAtPosition(i).toString() + "\n";
   } 
  }
  
  Toast.makeText(
    getActivity(), 
    prompt, 
    Toast.LENGTH_LONG).show();
 }

}

Modify listfragment1.xml to add android:choiceMode="multipleChoice" in <ListView>.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingLeft="8dp"
    android:paddingRight="8dp" >

    <ListView
        android:id="@id/android:list"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:choiceMode="multipleChoice"
        android:drawSelectorOnTop="false" />

    <TextView
        android:id="@id/android:empty"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="No data" />

</LinearLayout>

Download the files.

Example to implement Android TextSwitcher

android.widget.TextSwitcher is a specialized ViewSwitcher that contains only children of type TextView. A TextSwitcher is useful to animate a label on screen. Whenever setText(CharSequence) is called, TextSwitcher animates the current text out and animates the new text in.

Example code to implement TextSwitcher.

package com.example.androidtextswitcher;

import com.example.androidviewanimator.R;

import android.os.Bundle;
import android.app.Activity;
import android.graphics.Color;
import android.graphics.Typeface;
import android.view.Gravity;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.TextSwitcher;
import android.widget.TextView;
import android.widget.ViewSwitcher.ViewFactory;

public class MainActivity extends Activity {

 Button buttonNext;
 TextSwitcher textSwitcher;

 Animation slide_in_left, slide_out_right;

 String[] TextToSwitched = { "Sunday", "Monday", "Tuesday", "Wednesday",
   "Thursday", "Friday", "Saturday" };
 int curIndex;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);

  buttonNext = (Button) findViewById(R.id.next);
  textSwitcher = (TextSwitcher) findViewById(R.id.textswitcher);

  slide_in_left = AnimationUtils.loadAnimation(this,
    android.R.anim.slide_in_left);
  slide_out_right = AnimationUtils.loadAnimation(this,
    android.R.anim.slide_out_right);

  textSwitcher.setInAnimation(slide_in_left);
  textSwitcher.setOutAnimation(slide_out_right);
  
  textSwitcher.setFactory(new ViewFactory(){

   @Override
   public View makeView() {
    TextView textView = new TextView(MainActivity.this);
    textView.setTextSize(30);
    textView.setTextColor(Color.RED);
    textView.setGravity(Gravity.CENTER_HORIZONTAL);
    textView.setTypeface(Typeface.DEFAULT_BOLD);
    textView.setShadowLayer(10, 10, 10, Color.BLACK);
    return textView;
   }});

  curIndex = 0;
  textSwitcher.setText(TextToSwitched[curIndex]);

  buttonNext.setOnClickListener(new OnClickListener() {

   @Override
   public void onClick(View arg0) {
    if(curIndex == TextToSwitched.length-1){
     curIndex = 0;
     textSwitcher.setText(TextToSwitched[curIndex]);
    }else{
     textSwitcher.setText(TextToSwitched[++curIndex]);
    }
   }
  });
 }

}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:autoLink="web"
        android:text="http://android-er.blogspot.com/"
        android:textStyle="bold" />

    <TextSwitcher
        android:id="@+id/textswitcher"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

    <Button
        android:id="@+id/next"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="next" />

</LinearLayout>

Example of ViewAnimator

android.widget.ViewAnimator is a subclass of FrameLayout container that will perform animations when switching between its views.

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:autoLink="web"
        android:text="http://android-er.blogspot.com/"
        android:textStyle="bold" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal" >

        <Button
            android:id="@+id/prev"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="previous" />

        <Button
            android:id="@+id/next"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="next" />
    </LinearLayout>

    <ViewAnimator
        android:id="@+id/viewanimator"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/ic_launcher" />

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView 1" />

        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Button 2" />

        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Button 3" />

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical"
            android:gravity="center" >

            <Button
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="- Button 4 -" />

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="LinearLayout 4" />
        </LinearLayout>
    </ViewAnimator>

</LinearLayout>

package com.example.androidviewanimator;

import android.os.Bundle;
import android.app.Activity;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.ViewAnimator;

public class MainActivity extends Activity {
 
 Button buttonPrev, buttonNext;
 ViewAnimator viewAnimator;
 
 Animation slide_in_left, slide_out_right;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  
  buttonPrev = (Button)findViewById(R.id.prev);
  buttonNext = (Button)findViewById(R.id.next);
  viewAnimator = (ViewAnimator)findViewById(R.id.viewanimator);
  
  slide_in_left = AnimationUtils.loadAnimation(this, android.R.anim.slide_in_left);
  slide_out_right = AnimationUtils.loadAnimation(this, android.R.anim.slide_out_right);
  
  viewAnimator.setInAnimation(slide_in_left);
  viewAnimator.setOutAnimation(slide_out_right);
  
  buttonPrev.setOnClickListener(new OnClickListener(){

   @Override
   public void onClick(View arg0) {
    viewAnimator.showPrevious();
   }});
  
  buttonNext.setOnClickListener(new OnClickListener(){

   @Override
   public void onClick(View arg0) {
    viewAnimator.showNext();
   }});
 }

}

---

more related example:

• ViewSwitcher
• ImageSwitcher
• TextSwitcher
• ViewFlipper
• Bi-direction sliding
• Using GestureDetector to detect user swipe, onFling()
• Detect Gesture by implementing GestureDetector.SimpleOnGestureListener

New UI features and design guidelines for Android 4.4 KitKat

Android Design in Action: New in Android 4.4