Question

DefaultTableModel modeltable = new DefaultTableModel(8,8);

table = new JTable(modeltable);
table.setBorder(BorderFactory.createLineBorder (Color.blue, 2));

int height = table.getRowHeight();
table.setRowHeight(height=50);

table.setColumnSelectionAllowed(true);
table.setDragEnabled(true);

le1.setFillsViewportHeight(true);

panel.add(table);
panel.setSize(400,400);

    DnDListener dndListener = new DnDListener();
    DragSource dragSource = new DragSource();
    DropTarget dropTarget1 = new DropTarget(table, dndListener);

   DragGestureRecognizer dragRecognizer2 = dragSource.
            createDefaultDragGestureRecognizer(option1, 
          DnDConstants.ACTION_COPY, dndListener);
   DragGestureRecognizer dragRecognizer3 = dragSource.
            createDefaultDragGestureRecognizer(option2, 
            DnDConstants.ACTION_COPY, dndListener);


}
}

我有一个问题，即将鼠标监听器添加到“table”（即drop target），以便在从鼠标移动的任何地方接受drop组件。在此代码中，当组件进入放置目标时，它总是进入默认位置。我无法自定义放置目标上的位置。请有人帮我这个。提前谢谢

Answer 1

那些听众太低级了。实现dnd的适当方法是实现自定义TransferHandler并将该自定义处理程序设置为您的表。

 public class MyTransferHandler extends TransferHandler {

    public boolean canImport(TransferHandler.TransferSupport info) {
        // we only import Strings
        if (!info.isDataFlavorSupported(DataFlavor.stringFlavor)) {
            return false;
        }

        JTable.DropLocation dl = (JTable.DropLocation)info.getDropLocation();
        // ... your code to decide whether the data can be dropped based on location 
    }

    public boolean importData(TransferHandler.TransferSupport info) {
        if (!info.isDrop()) {
            return false;
        }

        // Check for String flavor
        if (!info.isDataFlavorSupported(DataFlavor.stringFlavor)) {
            displayDropLocation("Table doesn't accept a drop of this type.");
            return false;
        }

        JTable.DropLocation dl = (JTable.DropLocation)info.getDropLocation();
        // ... your code to handle the drop
   }

}

// usage
myTable.setTransferHandler(new MyTransferHandler());

有关详细信息，请参阅Swing标记说明中链接到的在线教程中的示例，即chapter Drag and Drop上面的代码段是从BasicDnD示例中进行的。＆/ p;

添加鼠标侦听器以放置目标

1 个答案: