实例详解用户输入 i. 检测常用手势
效果：一个手指实现（所有手势事件）和（部分事件的）；
A.所有手势
activity_main.xml
<TextView android:id="@+id/gesture" android:layout_width="match_parent" android:layout_height="150dp" android:gravity="center" android:text="单击手势变化"/><TextView android:id="@+id/doubleTap" android:layout_width="match_parent" android:layout_height="150dp" android:gravity="center" android:text="双击手势变化"/>
MainActivity.java
publicclassMainActivityextendsActivity
{
privatestaticfinalStringLOG_TAG="HelloGesture";
privateGestureDetectormGestureDetector=null;
privateTextViewmGestureTextView=null;
privateTextViewmDoubleTapTextView=null;
@Override
protectedvoidonCreate(BundlesavedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mGestureTextView=(TextView)findViewById(R.id.gesture);
mDoubleTapTextView=(TextView)findViewById(R.id.doubleTap);
//构造GestureDetector对象，传入监听器对象
mGestureDetector=newGestureDetector(this,mOnGestureListener);
//传入双击监听器对象
mGestureDetector.setOnDoubleTapListener(mDoubleTapListener);
}
@OverridepublicbooleanonTouchEvent(MotionEventevent)
{
//在onTouchEvent方法中将事件传递给手势检测对象，否则手势监听对象中的回调函数是不会被调用的
mGestureDetector.onTouchEvent(event);
returnsuper.onTouchEvent(event);
}
privateOnGestureListenermOnGestureListener=newOnGestureListener()
{
@Override
publicbooleanonSingleTapUp(MotionEvente)
{
Log.i(LOG_TAG,"onSingleTapUp:"+e.toString());
mGestureTextView.setText("onSingleTapUp:");
returnfalse;
}
@Override
publicvoidonShowPress(MotionEvente)
{
Log.i(LOG_TAG,"onShowPress:"+e.toString());
mGestureTextView.setText("onShowPress:");
}
@Override
publicbooleanonScroll(MotionEvente1,MotionEvente2,
floatdistanceX,floatdistanceY)
{
Log.i(LOG_TAG,"onScroll:"+e1.toString()+","+e2.toString());
mGestureTextView.setText("onScroll");
returnfalse;
}@Override
publicvoidonLongPress(MotionEvente)
{
Log.i(LOG_TAG,"onLongPress:"+e.toString());
mGestureTextView.setText("onLongPress:");
}
@Override
publicbooleanonFling(MotionEvente1,MotionEvente2,floatvelocityX,
floatvelocityY)
{
Log.i(LOG_TAG,"onFling:"+e1.toString()+","+e2.toString());
mGestureTextView.setText("onFling");
returnfalse;
}
@Override
publicbooleanonDown(MotionEvente)
{
Log.i(LOG_TAG,"onDown:"+e.toString());
mGestureTextView.setText("onDown:");
returnfalse;
}
};privateOnDoubleTapListenermDoubleTapListener=newOnDoubleTapListener()
{
@Override
publicbooleanonSingleTapConfirmed(MotionEvente)
{
Log.i("LOG_TAG","onSingleTapConfirmed:"+e.toString());
mDoubleTapTextView.setText("onSingleTapConfirmed:");
returnfalse;
}
@Override
publicbooleanonDoubleTapEvent(MotionEvente)
{
Log.i("LOG_TAG","onDoubleTapEvent:"+e.toString());
mDoubleTapTextView.setText("onDoubleTapEvent:");
returnfalse;
}
@Override
publicbooleanonDoubleTap(MotionEvente)
{
Log.i("LOG_TAG","onDoubleTap:"+e.toString());
mDoubleTapTextView.setText("onDoubleTap:");
returnfalse;
}
};}
B.部分手势
如果你仅仅只想处理几种手势，你可以选择继承GestureDetector.SimpleOnGestureListener类，而不是实现
GestureDetector.OnGestureListener接口
MainActivity.java
publicclassMainActivityextendsActivity
{
privateGestureDetectormGestureDetector=null;
privateTextViewmGestureTextView=null;
privateTextViewmDoubleTapTextView=null;
@Override
protectedvoidonCreate(BundlesavedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mGestureTextView=(TextView)findViewById(R.id.gesture);
mDoubleTapTextView=(TextView)findViewById(R.id.doubleTap);
//构造GestureDetector对象，传入监听器对象
mGestureDetector=newGestureDetector(this,newMyGestureListener());
//传入双击监听器对象
}
@Override
publicbooleanonTouchEvent(MotionEventevent)
{
//在onTouchEvent方法中将事件传递给手势检测对象，否则手势监听对象中的回调函数是不会被调用的
this.mGestureDetector.onTouchEvent(event);
returnsuper.onTouchEvent(event);
}
classMyGestureListenerextendsGestureDetector.SimpleOnGestureListener
{
privatestaticfinalStringDEBUG_TAG="Gestures";
@Override
publicbooleanonFling(MotionEvente1,MotionEvente2,floatvelocityX,
floatvelocityY)
{
Log.d(DEBUG_TAG,"onFling:"+e1.toString()+","+e2.toString());
mGestureTextView.setText("onFling");
returnfalse;
}
@Override
publicbooleanonDown(MotionEvente)
{
Log.d(DEBUG_TAG,"onDown:"+e.toString());
mGestureTextView.setText("onDown:");
returnfalse;
}
}}