Why Doesn't My JLabel Appear on the Java Glass Pane?

Placing Components on Glass Pane

The provided code snippet demonstrates the placement of a component on a glass pane. The glass pane is a transparent layer that sits on top of a Java GUI, allowing components to be dragged and dropped between containers without affecting the underlying components.

Problem

The user attempts to place a JLabel component on the glass pane, but it does not appear.

Solution

To place a component on the glass pane, the following steps are crucial:

1. Create a Glass Pane: Add a JPanel as the glass pane to the JFrame using setGlassPane(JPanel).
2. Make Glass Pane Visible: Set the visibility of the glass pane to true using getGlassPane().setVisible(true).
3. Add Component to Glass Pane: Add the desired component (in this case, the JLabel) to the glass pane using getGlassPane().add(JLabel).
4. Configure Component: Ensure that the component has valid bounds and is made visible.

Additional Notes

• Layout Manager: Ensure that the glass pane is not using a layout manager that will alter the component's size.
• Location: Use setLocation() to animate the dragged component.
• JLayeredPane: An alternative to using a glass pane is to use a JLayeredPane, where layers can be added and modified independently.

Example Code

MainFrame mf = new MainFrame();

// Create glass pane
JPanel glassPane = new JPanel();
mf.setGlassPane(glassPane);

JLabel l = new JLabel();
l.setText("Hello");
l.setBounds(10, 10, 50, 20);

// Add component to glass pane
glassPane.add(l);

// Enable glass pane
glassPane.setVisible(true);

mf.setVisible(true);

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