Java Swing: Enabling/Disabling all components in JPanel
java, jpanel, swing
Solution
It requires a recursive call.
import java.awt.*;
import javax.swing.*;
public class DisableAllInContainer {
public void enableComponents(Container container, boolean enable) {
Component[] components = container.getComponents();
for (Component component : components) {
component.setEnabled(enable);
if (component instanceof Container) {
enableComponents((Container)component, enable);
}
}
}
DisableAllInContainer() {
JPanel gui = new JPanel(new BorderLayout());
final JPanel container = new JPanel(new BorderLayout());
gui.add(container, BorderLayout.CENTER);
JToolBar tb = new JToolBar();
container.add(tb, BorderLayout.NORTH);
for (int ii=0; ii<3; ii++) {
tb.add(new JButton("Button"));
}
JTree tree = new JTree();
tree.setVisibleRowCount(6);
container.add(new JScrollPane(tree), BorderLayout.WEST);
container.add(new JTextArea(5,20), BorderLayout.CENTER);
final JCheckBox enable = new JCheckBox("Enable", true);
enable.addActionListener(new ActionListener(){
@Override
public void actionPerformed(ActionEvent ae) {
enableComponents(container, enable.isSelected());
}
});
gui.add(enable, BorderLayout.SOUTH);
JOptionPane.showMessageDialog(null, gui);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable(){
@Override
public void run() {
new DisableAllInContainer();
}
});
}}
Problem
I have a JPanel which contains a JToolbar (including few buttons without text) and a JTable and I need to enable/disable (make internal widgets not clickable). I tried this: ``` JPanel panel = ....; for (Component c : panel.getComponents()) c.setEnabled(enabled); ``` but it doesn't work. Is there a better and more generic solution to enable/disable all internal components in a JPanel? I have partially solved my problem using JLayer starting from the example here http://docs.oracle.com/javase/tutorial/uiswing/misc/jlayer.html: ``` layer = new JLayer<JComponent>(myPanel, new BlurLayerUI(false)); ..... ((BlurLayerUI)layer.getUI()).blur(...); // switch blur on/off class BlurLayerUI extends LayerUI<JComponent> { private BufferedImage mOffscreenImage; private BufferedImageOp mOperation; private boolean blur; public BlurLayerUI(boolean blur) { this.blur = blur; float ninth = 1.0f / 9.0f; float[] blurKernel = { ninth, ninth, ninth, ninth, ninth, ninth, ninth, ninth, ninth }; mOperation = new ConvolveOp( new Kernel(3, 3, blurKernel), ConvolveOp.EDGE_NO_OP, null); } public void blur(boolean blur) { this.blur=blur; firePropertyChange("blur", 0, 1); } @Override public void paint (Graphics g, JComponent c) { if (!blur) { super.paint (g, c); return; } int w = c.getWidth(); int h = c.getHeight(); if (w == 0 || h == 0) { return; } // Only create the offscreen image if the one we have // is the wrong size. if (mOffscreenImage == null || mOffscreenImage.getWidth() != w || mOffscreenImage.getHeight() != h) { mOffscreenImage = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB); } Graphics2D ig2 = mOffscreenImage.createGraphics(); ig2.setClip(g.getClip()); super.paint(ig2, c); ig2.dispose(); Graphics2D g2 = (Graphics2D)g; g2.drawImage(mOffscreenImage, mOperation, 0, 0); } @Override public void applyPropertyChange(PropertyChangeEvent pce, JLayer l) { if ("blur".equals(pce.getPropertyName())) { l.repaint(); } } } ``` I still have 2 problems: In the link above events are relative to mouse only. How can I manage the keyboard events? How can I create a "gray out" effect in place of blur?