Question

我有一个AbsoluteLayout我希望通过我的触摸点移动我的ImageView这个布局，查看我的代码，当我触摸任何点时，一切都很好，点保存在变量中，但ImageView消失了，任何想法？

我的XML布局：

    <ImageView
        android:id="@+id/FirstBall"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_x="59dp"
        android:layout_y="446dp"
        android:src="@drawable/redball" />

</AbsoluteLayout>

我的代码：

FstBall=(ImageView)findViewById(R.id.FirstBall);
FstBall.setOnTouchListener(new OnTouchListener(){
    @Override
    public boolean onTouch(View v, MotionEvent event) {
    float x = event.getX();
    float y = event.getY();
    int action = event.getAction();
    float FnlResX = 0;
    float FnlResY = 0;
    if (action == MotionEvent.ACTION_MOVE){
    FnlResX = x;
    FnlResY = y;
    int tst1 = (int) FnlResX;
    int tst2= (int) FnlResY;
    FstBall.scrollBy(tst1, tst2);
    }
    return true;
    }
    });

Answer 1

这是一种预期的行为，因为你只是滚动窗口而不是实际移动视图。正确的方法是覆盖布局的onTouchEvent方法。

public class MyAbsoluteLayout extends AbsoluteLayout{

   private static final String TAG = MyAbsoluteLayout.class.getSimpleName();

   private int mDepth;

   @Override
   public boolean onTouchEvent(MotionEvent event){
        final View child = getChildAt(mDepth);
        if(child == null){
            Log.e(TAG, "no child at selected depth");
            return super.onTouchEvent(event);
        }
        final ViewGroup.MarginLayoutParams params = (ViewGroup.MarginLayoutParams)   child.getLayoutParams();
        params.leftMargin = event.getX();
        params.topMargin = event.getY();
        child.setLayoutParams(params);
        return super.onTouchEvent(event);
    }

    public void setMovingChildDepth(final int depth){
       mDepth = depth;
    }
}

public class MyActivity extends Activity{

    public void onCreate(Bundle data){
        super.onCreate(data);

        final MyAbsoluteLayout layout = new MyAbsoluteLayout(this);
        final ViewGroup.MarginLayoutParams layoutParams = new ViewGroup.MarginLayoutParams(FILL_PARENT,FILL_PARENT);
        layout.setLayoutParams(layoutParams);

        final ImageView imageView = new ImageView(this);
        final ViewGroup.MarginLayoutParams viewParams = new ViewGroup.MarginLayoutParams(100,100);
        params.leftMargin = 100;
        params.topMargin = 100;
        imageView.setBackgroundDrawable(yourDrawable);
        layout.addView(imageView,params);

        layout.setMovingChildDepth(layout.indexOfChild(imageView));

        setContentView(layout);
    }
}

Answer 2

@Override
public boolean onTouchEvent(MotionEvent event) {
super.onTouchEvent(event);
AbsoluteLayout.LayoutParams params = new AbsoluteLayout.LayoutParams(FstBall.getLayoutParams());
params.x = (int) event.getX();
params.y = (int) event.getY();
FstBall.setLayoutParams(params);
return true;
}

通过onTouch（）移动ImageView

2 个答案: