The Java Tutorials have been written for JDK 8. Examples and practices described in this page don't take advantage of improvements introduced in later releases and might use technology no longer available.
See Java Language Changes for a summary of updated language features in Java SE 9 and subsequent releases.
See JDK Release Notes for information about new features, enhancements, and removed or deprecated options for all JDK releases.
An InternalFrameListener
is similar to a WindowListener
. Like the window listener, the internal frame listener listens for events that occur when the "window" has been shown for the first time, disposed of, iconified, deiconified, activated, or deactivated. Before using an internal frame listener, please familiarize yourself with the WindowListener
interface in How to Write Window Listeners.
The application shown in the following figure demonstrates internal frame events. The application listens for internal frame events from the Event Generator frame, displaying a message that describes each event.
Here is the internal frame event handling code:
public class InternalFrameEventDemo ... implements InternalFrameListener ... { ... public void internalFrameClosing(InternalFrameEvent e) { displayMessage("Internal frame closing", e); } public void internalFrameClosed(InternalFrameEvent e) { displayMessage("Internal frame closed", e); listenedToWindow = null; } public void internalFrameOpened(InternalFrameEvent e) { displayMessage("Internal frame opened", e); } public void internalFrameIconified(InternalFrameEvent e) { displayMessage("Internal frame iconified", e); } public void internalFrameDeiconified(InternalFrameEvent e) { displayMessage("Internal frame deiconified", e); } public void internalFrameActivated(InternalFrameEvent e) { displayMessage("Internal frame activated", e); } public void internalFrameDeactivated(InternalFrameEvent e) { displayMessage("Internal frame deactivated", e); } void displayMessage(String prefix, InternalFrameEvent e) { String s = prefix + ": " + e.getSource(); display.append(s + newline); } public void actionPerformed(ActionEvent e) { if (SHOW.equals(e.getActionCommand())) { ... if (listenedToWindow == null) { listenedToWindow = new JInternalFrame("Event Generator", true, //resizable true, //closable true, //maximizable true); //iconifiable //We want to reuse the internal frame, so we need to //make it hide (instead of being disposed of, which is //the default) when the user closes it. listenedToWindow.setDefaultCloseOperation( WindowConstants.HIDE_ON_CLOSE); listenedToWindow.addInternalFrameListener(this); ... } } ... } }
The InternalFrameListener Interface
The corresponding adapter class is
InternalFrameAdapter
.
Method | Purpose |
---|---|
internalFrameOpened(InternalFrameEvent) | Called just after the listened-to internal frame has been shown for the first time. |
internalFrameClosing(InternalFrameEvent) | Called in response to a user request that the listened-to internal frame be closed. By default, JInternalFrame hides the window when the user closes it. You can use the JInternalFrame setDefaultCloseOperation method to specify another option, which must be either DISPOSE_ON_CLOSE or DO_NOTHING_ON_CLOSE (both defined in WindowConstants , an interface that JInternalFrame implements). Or by implementing an internalFrameClosing method in the internal frame's listener, you can add custom behavior (such as bringing up dialogs or saving data) to internal frame closing. |
internalFrameClosed(InternalFrameEvent) | Called just after the listened-to internal frame has been disposed of. |
internalFrameIconified(InternalFrameEvent) internalFrameDeiconified(InternalFrameEvent) |
Called just after the listened-to internal frame is iconified or deiconified, respectively. |
internalFrameActivated(InternalFrameEvent) internalFrameDeactivated(InternalFrameEvent) |
Called just after the listened-to internal frame is activated or deactivated, respectively. |
Each internal frame event method has a single parameter: an
InternalFrameEvent
object. The InternalFrameEvent
class defines no generally useful methods. To get the internal frame that fired the event, use the getSource
method, which InternalFrameEvent
inherits from java.util.EventObject
.
No other source files currently contain internal frame listeners. However, internal frame listeners are very similar to WindowListener
s and several Swing programs have window listeners:
Example | Where Described | Notes |
---|---|---|
InternalFrameEventDemo |
This section | Reports all internal frame events that occur on one internal frame to demonstrate the circumstances under which internal frame events are fired. |
DialogDemo |
Text Component Features |
CustomDialog.java uses setDefaultCloseOperation instead of a window listener to determine what action to take when the user closes the window. |
SliderDemo |
How to Use Sliders | Listens for window iconify and deiconify events, so that it can stop the animation when the window is not visible. |