默认 DnD 支持

Technically speaking, the framework for drag and drop supports all Swing components — the data transfer mechanism is built into every JComponent. If you wanted, you could implement drop support for a JSlider so that it could fully participate in data transfer. While JSlider does not support drop by default, the components you would want (and expect) to support drag and drop do provide specialized built-in support.

The following components recognize the drag gesture once the setDragEnabled(true) method is invoked on the component. For example, once you invoke myColorChooser.setDragEnabled(true) you can drag colors from your color chooser:

• JColorChooser
• JEditorPane
• JFileChooser
• JFormattedTextField
• JList
• JTable
• JTextArea
• JTextField
• JTextPane
• JTree

The following components support drop out of the box. If you are using one of these components, your work is done.

• JEditorPane
• JFormattedTextField
• JPasswordField
• JTextArea
• JTextField
• JTextPane
• JColorChooser

The framework for drop is in place for the following components, but you need to plug in a small amount of code to customize the support for your needs.

• JList
• JTable
• JTree

For these critical components, Swing performs the drop location calculations and rendering; it allows you to specify a drop mode; and it handles component specific details, such as tree expansions. Your work is fairly minimal.