拖放透明面板Android

Question

我正在实现拖放方法。 我想拖出透明面板的图像拖入图层视图，但它会引发错误并强制关闭。

来自logcat的错误说：给定的视图不是com.example.drag.DragLayer的子视图。

xml使用DragLayer类。 什么错了？以及如何解决它？

这里是代码： “XML”

<com.example.drag.DragLayer 
xmlns:android="http://schemas.android.com/apk/res/android" 
xmlns:launcher="http://schemas.android.com/apk/res/com.android.launcher" 

android:id="@+id/drag_layer" 
android:layout_width="match_parent" 
android:layout_height="match_parent"> 

<com.example.drag.TransparentPanel 
android:id="@+id/popup_window" 
android:orientation="vertical" 
android:layout_width="wrap_content" 
android:layout_height="fill_parent" 
android:gravity="left" 
android:padding="1px" 
android:background="#ffffff"> 

<ScrollView android:id="@+id/ScrollView01" 
android:layout_width="fill_parent" 
android:layout_height="fill_parent"> 
<LinearLayout android:id="@+id/LinearLayout02" 
android:layout_width="wrap_content" 
android:layout_height="30px" 
android:orientation="vertical"> 
<TextView 
android:id="@+id/Text1" 
android:layout_width="fill_parent" 
android:layout_height="wrap_content" 
android:text="@string/hello" 
/> 
<ImageView 
android:id="@+id/Image1" 
android:src="@drawable/icon1" 
android:layout_weight="50" 
android:adjustViewBounds="true" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content" /> 
<ImageView 
android:id="@+id/Image2" 
android:src="@drawable/icon2" 
android:layout_weight="50" 
android:adjustViewBounds="true" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content" /> 

</LinearLayout> 
</ScrollView> 
</com.example.drag.TransparentPanel> 
</com.example.drag.DragLayer> 

这里是代码： “DragLayer.java”

public class DragLayer extends MyAbsoluteLayout 
implements DragSource, DropTarget 
{ 
DragController mDragController; 

    public DragLayer (Context context, AttributeSet attrs) { 
    super(context, attrs); 
} 

public void setDragController(DragController controller) { 
    mDragController = controller; 
} 

@Override 
public boolean dispatchKeyEvent(KeyEvent event) { 
    return mDragController.dispatchKeyEvent(event) || super.dispatchKeyEvent(event); 
} 

@Override 
public boolean onInterceptTouchEvent(MotionEvent ev) { 
    return mDragController.onInterceptTouchEvent(ev); 
} 

@Override 
public boolean onTouchEvent(MotionEvent ev) { 
    return mDragController.onTouchEvent(ev); 
} 

@Override 
public boolean dispatchUnhandledMove(View focused, int direction) { 
    return mDragController.dispatchUnhandledMove(focused, direction); 
} 

public void onDrop(DragSource source, int x, int y, int xOffset, int yOffset, 
    DragView dragView, Object dragInfo) 
{ 
View v = (View) dragInfo; 
toast ("DragLayer2.onDrop accepts view: " + v.getId() 
     + "x, y, xO, yO :" + new Integer (x) + ", " + new Integer (y) + ", " 
     + new Integer (xOffset) + ", " + new Integer (yOffset)); 

int w = v.getWidth(); 
int h = v.getHeight(); 
int left = x - xOffset; 
int top = y - yOffset; 
DragLayer.LayoutParams lp = new DragLayer.LayoutParams (w, h, left, top); 
this.updateViewLayout(v, lp); 
} 

public void onDragEnter(DragSource source, int x, int y, int xOffset, int yOffset, 
    DragView dragView, Object dragInfo) 
{ 
} 

public void onDragOver(DragSource source, int x, int y, int xOffset, int yOffset, 
    DragView dragView, Object dragInfo) 
{ 
} 

public void onDragExit(DragSource source, int x, int y, int xOffset, int yOffset, 
    DragView dragView, Object dragInfo) 
{ 
} 

public boolean acceptDrop(DragSource source, int x, int y, int xOffset, int yOffset, 
    DragView dragView, Object dragInfo) 
{ 
return true; 
} 

public Rect estimateDropLocation(DragSource source, int x, int y, int xOffset, int 

    yOffset, 
     DragView dragView, Object dragInfo, Rect recycle) 
{ 
return null; 
} 

public void toast (String msg) 
{ 
if (!DragActivity.Debugging) return; 
Toast.makeText (getContext(), msg, Toast.LENGTH_SHORT).show(); 
} // end toast 


} // end class 

Answer 1

不知道为什么正在使用Java的拖放的API。 请使用android专用拖放apis Drag and Drop Dev Guide