Android DragShadowBuilder粘在觸摸點的中心

Question

有誰可以幫我關於以下 -
1.它不應該堅持觸摸點，它應該從任何點開始拖動。
2. DragShadowBuilder視圖應當回退，而不會拖放到正確的目標上。

Answer 1

我通過創建自定義View.DragShadowBuilder類來實現此目的。

代碼相同的是：

public class CustomDragShadowBuilder extends View.DragShadowBuilder { 
View v; 
public CustomDragShadowBuilder(View v) { 
    super(v); 
    this.v=v; 
} 
@Override 
public void onDrawShadow(Canvas canvas) { 
    super.onDrawShadow(canvas); 

    /*Modify canvas if you want to show some custom view that you want 
     to animate, that you can check by putting a condition passed over 
     constructor. Here I'm taking the same view*/ 

    canvas.drawBitmap(getBitmapFromView(v), 0, 0, null); 
} 
@Override 
public void onProvideShadowMetrics(Point shadowSize, Point touchPoint) { 
/*Modify x,y of shadowSize to change the shadow view 
    according to your requirements. Here I'm taking the same view width and height*/ 
    shadowSize.set(v.getWidth(),v.getHeight()); 
/*Modify x,y of touchPoint to change the touch for the view 
as per your needs. You may pass your x,y position of finger 
to achieve your results. Here I'm taking the lower end point of view*/ 
    touchPoint.set(v.getWidth(), v.getHeight()); 
    } 
} 

轉換用的以位圖從here採取：

private Bitmap getBitmapFromView(View view) { 
    //Define a bitmap with the same size as the view 
    Bitmap returnedBitmap = Bitmap.createBitmap(view.getWidth(), view.getHeight(),Bitmap.Config.ARGB_8888); 
    //Bind a canvas to it 
    Canvas canvas = new Canvas(returnedBitmap); 
    //Get the view's background 
    Drawable bgDrawable =view.getBackground(); 
    if (bgDrawable!=null) 
     //has background drawable, then draw it on the canvas 
     bgDrawable.draw(canvas); 
    else 
     //does not have background drawable, then draw white background on the canvas 
     canvas.drawColor(Color.WHITE); 
    // draw the view on the canvas 
    view.draw(canvas); 
    //return the bitmap 
    return returnedBitmap; 
} 

雖然這是老問題，可能被證明是對他人有所幫助，誰想要使用自定義的DragShadowBuilder。

在代碼中的註釋是不言自明的，更多信息讓我知道。 希望它有幫助。