<-------------------------Activity----------------------------------->
public class MainActivity extends Activity {
private ImageView imageView;
float lastDistance=-1;
float x0=0;
float y0=0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
}
private void init() {
imageView = (ImageView) findViewById(R.id.imageView);
imageView.setOnTouchListener(new OnTouchListener() {
public boolean onTouch(View v, MotionEvent event) {
int action = event.getAction();
Log.i("TAG", "開始觸摸了。。");
switch (action) {
case MotionEvent.ACTION_UP://手指擡起
/*imageView.setX(event.getX());
imageView.setY(event.getY());*/
break;
case MotionEvent.ACTION_MOVE://手指移動
//得到觸摸點的個數
int count = event.getPointerCount();
if(count>1){
//獲得兩點的座標差
float distanceX=event.getX(0)-event.getX(1);
float distanceY=event.getY(0)-event.getY(1);
//兩點之間的距離
float betweenDistance=(float) Math.sqrt(distanceX*distanceX+distanceY*distanceY);
if(betweenDistance<1){
lastDistance=betweenDistance;
}else if(betweenDistance-lastDistance > 5){
lastDistance=betweenDistance;
//放大
RelativeLayout.LayoutParams params= (android.widget.RelativeLayout.LayoutParams) imageView.getLayoutParams();
params.width=(int) (imageView.getWidth()*1.1f);
params.height=(int) (imageView.getHeight()*1.1f);
imageView.setLayoutParams(params);
}else if(lastDistance-betweenDistance > 5){
lastDistance=betweenDistance;
//縮小
RelativeLayout.LayoutParams params= (android.widget.RelativeLayout.LayoutParams) imageView.getLayoutParams();
params.width=(int) (imageView.getWidth()*0.9f);
params.height=(int) (imageView.getHeight()*0.9f);
imageView.setLayoutParams(params);
}
}else if(count==1){
/*imageView.setX(event.getX());
imageView.setY(event.getY());*/
}
break;
}
return true;
}
});
}
}
<-------------------------xml文件----------------------------------->
<RelativeLayout 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"
tools:context=".MainActivity" >
<ImageView
android:id="@+id/imageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:background="@drawable/xk" />
</RelativeLayout>