X-Git-Url: http://git.nikiroo.be/?p=fanfix.git;a=blobdiff_plain;f=src%2Fbe%2Fnikiroo%2Ffanfix_swing%2Fgui%2Futils%2FListenerPanel.java;h=98202b2da42108c44beee3119fb32a2b4bf1cec1;hp=7ed5f8618b7676b96ad6acf7d8ce473ef9cd7f76;hb=d6c8579cb5debbdf7657d405e6529ba324903fcd;hpb=89f2c4799d6a9d16d2c909da175621e0f2eda301

diff --git a/src/be/nikiroo/fanfix_swing/gui/utils/ListenerPanel.java b/src/be/nikiroo/fanfix_swing/gui/utils/ListenerPanel.java
index 7ed5f86..98202b2 100644
--- a/src/be/nikiroo/fanfix_swing/gui/utils/ListenerPanel.java
+++ b/src/be/nikiroo/fanfix_swing/gui/utils/ListenerPanel.java
@@ -2,6 +2,8 @@ package be.nikiroo.fanfix_swing.gui.utils;
 
 import java.awt.event.ActionEvent;
 import java.awt.event.ActionListener;
+import java.util.LinkedList;
+import java.util.Queue;
 
 import javax.swing.JPanel;
 
@@ -10,12 +12,44 @@ import be.nikiroo.fanfix_swing.gui.SearchBar;
 /**
  * A {@link JPanel} with the default {@link ActionListener} add/remove/fire
  * methods.
+ * <p>
+ * Note that it will queue all events until at least one listener comes (or
+ * comes back!); this first (or at least curently unique) listener will drain
+ * the queue.
  * 
  * @author niki
  */
 public class ListenerPanel extends JPanel {
 	private static final long serialVersionUID = 1L;
 
+	private final Queue<ActionEvent> waitingQueue;
+
+	/**
+	 * Create a new {@link ListenerPanel}.
+	 */
+	public ListenerPanel() {
+		waitingQueue = new LinkedList<ActionEvent>();
+	}
+
+	/**
+	 * Check that this {@link ListenerPanel} currently has {@link ActionListener}s
+	 * that listen on it.
+	 * 
+	 * @return TRUE if it has
+	 */
+	public synchronized boolean hasListeners() {
+		return listenerList.getListenerList().length > 1;
+	}
+
+	/**
+	 * Check how many events are currently waiting for an {@link ActionListener}.
+	 * 
+	 * @return the number of waiting events (can be 0)
+	 */
+	public synchronized int getWaitingEventCount() {
+		return waitingQueue.size();
+	}
+
 	/**
 	 * Adds the specified action listener to receive action events from this
 	 * {@link SearchBar}.
@@ -23,6 +57,12 @@ public class ListenerPanel extends JPanel {
 	 * @param listener the action listener to be added
 	 */
 	public synchronized void addActionListener(ActionListener listener) {
+		if (!hasListeners()) {
+			while (!waitingQueue.isEmpty()) {
+				listener.actionPerformed(waitingQueue.remove());
+			}
+		}
+
 		listenerList.add(ActionListener.class, listener);
 	}
 
@@ -42,13 +82,17 @@ public class ListenerPanel extends JPanel {
 	 * @param listenerCommand A string that may specify a command (possibly one of
 	 *                        several) associated with the event
 	 */
-	protected void fireActionPerformed(String listenerCommand) {
+	protected synchronized void fireActionPerformed(String listenerCommand) {
 		ActionEvent e = new ActionEvent(this, ActionEvent.ACTION_PERFORMED, listenerCommand);
-		Object[] listeners = listenerList.getListenerList();
-		for (int i = listeners.length - 2; i >= 0; i -= 2) {
-			if (listeners[i] == ActionListener.class) {
-				((ActionListener) listeners[i + 1]).actionPerformed(e);
+		if (hasListeners()) {
+			Object[] listeners = listenerList.getListenerList();
+			for (int i = listeners.length - 2; i >= 0; i -= 2) {
+				if (listeners[i] == ActionListener.class) {
+					((ActionListener) listeners[i + 1]).actionPerformed(e);
+				}
 			}
+		} else {
+			waitingQueue.add(e);
 		}
 	}
 }