Question

我正在尝试设置一个显示图像按钮网格的网格视图。我还设置了一个拖动图层，以便您可以单击并将按钮拖动到不同的位置。我的问题是网格视图不会显示图像按钮。以下是设置布局的两个xml文件。 main.xml和row_grid.xml位于res / layout。

main.xml中：

<?xml version="1.0" encoding="utf-8"?>
<edu.purdue.app.DragLayer
xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/drag_layer"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">
    <GridView xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/button_grid_view"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:numColumns="@integer/num_columns"
        android:verticalSpacing="10dp"
        android:horizontalSpacing="10dp"
        android:stretchMode="columnWidth"
        android:gravity="center"
        android:layout_weight="0.8"
        android:background="@color/light_gray"
      />

    </edu.purdue.app.DragLayer>

row_grid.xml：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:padding="5dp" >

    <ImageButton
        android:id="@+id/MapButton"
        android:layout_width="104dp"
        android:layout_height="92dp"
        android:gravity="center_horizontal|bottom"
        android:src="@drawable/ic_launcher" >
    </ImageButton>
</LinearLayout>

主要活动：

public class PurdueAppActivity extends Activity implements View.OnLongClickListener, View.OnClickListener,
    View.OnTouchListener{
        public static final boolean Debugging = false;
        DragController mDragController;   // Object that handles a drag-drop sequence. It intersacts with DragSource and DropTarget objects.
        DragLayer mDragLayer;             // The ViewGroup within which an object can be dragged.

        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);

            GridView gridView = (GridView) findViewById(R.id.button_grid_view);
            gridView.setAdapter (new ImageButtonCellAdapter(this,R.layout.row_grid));
            // gridView.setOnItemClickListener (this);
            mDragController = new DragController(this);
            mDragLayer = (DragLayer) findViewById(R.id.drag_layer);
            mDragLayer.setDragController (mDragController);
            mDragLayer.setGridView (gridView);
    public boolean onLongClick(View v) {
            // TODO Auto-generated method stub
            return startDrag (v);
        }

        public boolean startDrag (View v)
        {
            DragSource dragSource = (DragSource) v;

            // We are starting a drag. Let the DragController handle it.
            mDragController.startDrag (v, dragSource, dragSource, DragController.DRAG_ACTION_MOVE);

            return true;
        }

    }

最后，这是适配器类'getView（）方法，应该设置它：

public View getView (int position, View convertView, ViewGroup parent) 
{
    mParentView = parent;

    ImageButtonCell v = null;
    if (convertView == null) {
        // If it's not recycled, create a new ImageCell.
        v = new ImageButtonCell (mContext);
        v.setLayoutParams(new GridView.LayoutParams(85, 85));
        v.setScaleType(ImageView.ScaleType.CENTER_CROP);
        v.setPadding(8, 8, 8, 8);

    } else {
        v = (ImageButtonCell) convertView;
    }

    v.mCellNumber = position;
    v.mGrid = (GridView) mParentView;
    v.mEmpty = true;
//    v.setBackgroundResource (R.color.drop_target_enabled);
    v.setBackgroundResource (R.color.light_gray);

    //v.mGrid.requestDisallowInterceptTouchEvent (true);

    //v.setImageResource (R.drawable.hello);

    // Set up to relay events to the activity.
    // The activity decides which events trigger drag operations.
    // Activities like the Android Launcher require a long click to get a drag operation started.
    v.setOnTouchListener ((View.OnTouchListener) mContext);
    v.setOnClickListener ((View.OnClickListener) mContext);
    v.setOnLongClickListener ((View.OnLongClickListener) mContext);

    return v;
}

Answer 1

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    View v = convertView;
    if (v == null) {
        LayoutInflater vi = (LayoutInflater)getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        v = vi.inflate(R.layout.row_grid, null);
    }

    ImageButton imagebtn = (ImageButton)v.findViewById(R.id.MapButton);
    //do something on imagebtn
    return v;
}

Gridview不会显示图像按钮

1 个答案: