如何用 Java 實現透明 JDialog?
JDialog 是 Dialog 類的子類,並且不包含視窗右上角的最小化 和最大化 按鈕。有兩種型別的對話方塊,即模態 和非模態。對話方塊的預設佈局是BorderLayout。
在下面的程式中,我們可以透過自定義AlphaContainer 類並覆蓋paintComponent()方法來實現一個透明的 JDialog。
示例
import java.awt.*; import javax.swing.*; public class TransparentDialog { public static void main (String[] args) { JDialog dialog = new JDialog(); dialog.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); dialog.getRootPane().setOpaque(false); dialog.setUndecorated(true); dialog.setBackground(new Color (0, 0, 0, 0)); JPanel panel = new JPanel(new BorderLayout ()); panel.setBackground(new Color (0, 0, 0, 64)); dialog.add(new AlphaContainer(panel)); JSlider slider = new JSlider(); slider.setBackground(new Color(255, 0, 0, 32)); panel.add (new AlphaContainer(slider), BorderLayout.NORTH); JButton button = new JButton("Label text"); button.setContentAreaFilled(false); panel.add(button, BorderLayout.SOUTH); dialog.setSize(400, 300); dialog.setLocationRelativeTo(null); dialog.setVisible(true); } } class AlphaContainer extends JComponent { private JComponent component; public AlphaContainer(JComponent component){ this.component = component; setLayout(new BorderLayout()); setOpaque(false); component.setOpaque(false); add(component); } @Override public void paintComponent(Graphics g) { g.setColor(component.getBackground()); g.fillRect(0, 0, getWidth(), getHeight()); } }
輸出
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