Android中使用ViewFlipper进行手势切换实例
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：
<?xmlversion="1.0"encoding="utf-8"?>
<ViewFlipperxmlns: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：
publicclassMyGestureDetectorextendsSimpleOnGestureListener
{
privatestaticfinalintSWIPE_MIN_DISTANCE=120;
privatestaticfinalintSWIPE_MAX_OFF_PATH=250;
privatestaticfinalintSWIPE_THRESHOLD_VELOCITY=200;
@Override
publicbooleanonFling(MotionEvente1,MotionEvente2,
floatvelocityX,floatvelocityY)
{
try
{
if(Math.abs(e1.getY()-e2.getY())>SWIPE_MAX_OFF_PATH)
{
returnfalse;
}
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(Exceptione)
{
}
returnfalse;
}
}
注意在Activity中重写onTouchEvent()函数：
privateViewFlipperviewFlipper;
privateAnimationslideLeftIn;
privateAnimationslideLeftOut;
privateAnimationslideRightIn;
privateAnimationslideRightOut;
privateGestureDetectorgestureDetector;
@Override
publicvoidonCreate(BundlesavedInstanceState)
{
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=newGestureDetector(newMyGestureDetector());
newView.OnTouchListener()
{
publicbooleanonTouch(Viewv,MotionEventevent)
{
if(gestureDetector.onTouchEvent(event))
{
returntrue;
}
returnfalse;
}
};
}
@Override
publicbooleanonTouchEvent(MotionEventevent)
{
if(gestureDetector.onTouchEvent(event))
{
returntrue;
}
else
{
returnfalse;
}
}
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
<?xmlversion="1.0"encoding="utf-8"?>
<setxmlns: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
<?xmlversion="1.0"encoding="utf-8"?>
<setxmlns: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
<?xmlversion="1.0"encoding="utf-8"?>
<setxmlns: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
<?xmlversion="1.0"encoding="utf-8"?>
<setxmlns: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