Version 18, July 2015

[GpsPrune.git] / tim / prune / gui / TripleStateCheckBox.java

diff --git a/tim/prune/gui/TripleStateCheckBox.java b/tim/prune/gui/TripleStateCheckBox.java
new file mode 100644 (file)
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--- /dev/null
+++ b/tim/prune/gui/TripleStateCheckBox.java
@@ -0,0 +1,78 @@
+package tim.prune.gui;
+
+import java.awt.event.ItemEvent;
+import java.awt.event.ItemListener;
+
+import javax.swing.ImageIcon;
+import javax.swing.JCheckBox;
+
+/**
+ * Class to represent a checkbox with three states, through which it cycles
+ * Instead of calling isChecked, need to use getCurrentState which will
+ * return 0, 1 or 2
+ */
+public class TripleStateCheckBox extends JCheckBox implements ItemListener
+{
+       /** Array of icons to be used */
+       private ImageIcon[] _icons = new ImageIcon[3];
+       /** Current state 0, 1 or 2 */
+       private int _currState = 0;
+
+       /** Inner class to proxy the listening events */
+       private class ProxyListener implements ItemListener
+       {
+               /** Listener onto which some of the events will be passed */
+               private ItemListener _listener = null;
+               /** Constructor */
+               ProxyListener(ItemListener inListener) {_listener = inListener;}
+               /** React to events, and only pass on the selected ones */
+               public void itemStateChanged(ItemEvent arg0) {
+                       if (arg0.getStateChange() == ItemEvent.SELECTED) {
+                               _listener.itemStateChanged(arg0);
+                       }
+               }
+       }
+
+       /** Constructor */
+       public TripleStateCheckBox()
+       {
+               addItemListener(this);
+       }
+
+       /** Set the current state */
+       public void setCurrentState(int inState)
+       {
+               _currState = inState % 3;
+               setIcon(_icons[_currState]);
+               setSelected(false);
+               setSelectedIcon(_icons[(_currState+1)%3]);
+       }
+
+       /** @return current state 0, 1 or 2 */
+       public int getCurrentState()
+       {
+               return _currState;
+       }
+
+       /**
+        * Set the icon to use for the given index
+        * @param inIndex index 0, 1 or 2
+        * @param inIcon icon to use for that state
+        */
+       public void setIcon(int inIndex, ImageIcon inIcon)
+       {
+               _icons[inIndex % 3] = inIcon;
+       }
+
+       @Override
+       /** Intercept listener adding by putting a proxy inbetween */
+       public void addItemListener(ItemListener inListener) {
+               super.addItemListener(new ProxyListener(inListener));
+       }
+
+       /** React to a selection event by advancing the state */
+       public void itemStateChanged(ItemEvent inEvent)
+       {
+               setCurrentState(_currState + 1);
+       }
+}