Android中使用ViewFlipper进行手势切换实例_Android

本文实例讲述了Android中使用ViewFlipper进行手势切换的方法，分享给大家供大家参考。具体实现步骤如下：

首先在layout的xml文件中定义一个ViewFlipper：

复制代码代码如下:

	<?xml version="1.0" encoding="utf-8"?> 

	<ViewFlipper xmlns:android="http://schemas.android.com/apk/res/android" 

	        android:id="@+id/viewFlipper" 

	        android:layout_width="fill_parent"  

	        android:layout_height="fill_parent" 

	        > 

	    <LinearLayout 

	        android:layout_width="fill_parent" 

	        android:layout_height="fill_parent" 

	        > 

	        <TextView 

	            android:layout_width="fill_parent" 

	            android:layout_height="fill_parent" 

	            android:background="#FF0000" 

	            /> 

	    </LinearLayout> 

	    <LinearLayout 

	        android:layout_width="fill_parent" 

	        android:layout_height="fill_parent" 

	        > 

	        <TextView 

	            android:layout_width="fill_parent" 

	            android:layout_height="fill_parent" 

	            android:background="#00FF00" 

	            /> 

	    </LinearLayout> 

	</ViewFlipper>

声明一个新的GestureDetector，重写它的onFling()函数，在这个函数里面判断手势，这里为横向的拖动：

复制代码代码如下:

	public class MyGestureDetector extends SimpleOnGestureListener 

	{ 

	    private static final int SWIPE_MIN_DISTANCE = 120; 

	    private static final int SWIPE_MAX_OFF_PATH = 250; 

	    private static final int SWIPE_THRESHOLD_VELOCITY = 200; 

	    @Override 

	    public boolean onFling(MotionEvent e1, MotionEvent e2,  

	                           float velocityX, float velocityY) 

	    { 

	        try 

	        { 

	               if (Math.abs(e1.getY() - e2.getY()) > SWIPE_MAX_OFF_PATH) 

	               { 

	                   return false; 

	               } 

	               if(e1.getX() - e2.getX() > SWIPE_MIN_DISTANCE &&  

	                  Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) 

	               { 

	                viewFlipper.setInAnimation(slideLeftIn); 

	                   viewFlipper.setOutAnimation(slideLeftOut); 

	                viewFlipper.showNext(); 

	               } 

	               else  

	                if (e2.getX() - e1.getX() > SWIPE_MIN_DISTANCE &&  

	                    Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) 

	                { 

	                    viewFlipper.setInAnimation(slideRightIn); 

	                    viewFlipper.setOutAnimation(slideRightOut); 

	                    viewFlipper.showPrevious(); 

	                } 

	           } 

	        catch (Exception e) 

	        { 

	           } 

	           return false; 

	    } 

	}

注意在Activity中重写onTouchEvent()函数：

复制代码代码如下:

	private ViewFlipper viewFlipper; 

	private Animation slideLeftIn; 

	private Animation slideLeftOut; 

	private Animation slideRightIn; 

	private Animation slideRightOut; 

	private GestureDetector gestureDetector; 

	@Override 

	public void onCreate(Bundle savedInstanceState) 

	{ 

	    super.onCreate(savedInstanceState); 

	    setContentView(R.layout.main); 

	    viewFlipper = (ViewFlipper)findViewById(R.id.viewFlipper); 

	       slideLeftIn = AnimationUtils.loadAnimation(this, R.anim.slide_left_in); 

	       slideLeftOut = AnimationUtils.loadAnimation(this, R.anim.slide_left_out); 

	       slideRightIn = AnimationUtils.loadAnimation(this, R.anim.slide_right_in); 

	       slideRightOut = AnimationUtils.loadAnimation(this, R.anim.slide_right_out); 

	       gestureDetector = new GestureDetector(new MyGestureDetector()); 

	       new View.OnTouchListener() 

	       { 

	           public boolean onTouch(View v, MotionEvent event) 

	           { 

	               if (gestureDetector.onTouchEvent(event)) 

	               { 

	                   return true; 

	               } 

	               return false; 

	           } 

	       }; 

	} 

	@Override 

	public boolean onTouchEvent(MotionEvent event) 

	{ 

	    if (gestureDetector.onTouchEvent(event)) 

	    { 

	        return true; 

	    } 

	    else 

	    { 

	        return false; 

	    } 

	}

最后，在res文件夹下新建一个anim文件夹，用来存放view之间切换的动画文件：

1.slide_left_in.xml

复制代码代码如下:

	<?xml version="1.0" encoding="utf-8"?> 

	<set xmlns:android="http://schemas.android.com/apk/res/android"> 

	    <translate 

	        android:fromXDelta="100%p"  

	        android:toXDelta="0"  

	        android:duration="500" 

	        /> 

	    <alpha 

	        android:fromAlpha="0.0"  

	        android:toAlpha="1.0" 

	        android:duration="500" 

	        /> 

	</set>

2.slide_left_out.xml

复制代码代码如下:

	<?xml version="1.0" encoding="utf-8"?> 

	<set xmlns:android="http://schemas.android.com/apk/res/android"> 

	    <translate 

	        android:fromXDelta="0"  

	        android:toXDelta="-100%p"  

	        android:duration="500" 

	        /> 

	    <alpha 

	        android:fromAlpha="1.0"  

	        android:toAlpha="0.0"  

	        android:duration="500" 

	        /> 

	</set>

3.slide_right_in.xml

复制代码代码如下:

	<?xml version="1.0" encoding="utf-8"?> 

	<set xmlns:android="http://schemas.android.com/apk/res/android"> 

	    <translate  

	        android:fromXDelta="-100%p"  

	        android:toXDelta="0"  

	        android:duration="500" 

	        /> 

	    <alpha 

	        android:fromAlpha="0.0"  

	        android:toAlpha="1.0" 

	        android:duration="500" 

	        /> 

	</set>

4.slide_right_out.xml

复制代码代码如下:

	<?xml version="1.0" encoding="utf-8"?> 

	<set xmlns:android="http://schemas.android.com/apk/res/android"> 

	    <translate  

	        android:fromXDelta="0"  

	        android:toXDelta="100%p"  

	        android:duration="500" 

	        /> 

	    <alpha 

	        android:fromAlpha="1.0"  

	        android:toAlpha="0.0" 

	        android:duration="500" 

	        /> 

	</set>

希望本文所述对大家的Android程序设计有所帮助