Fixes issue 3724: AED shows validation error on name when editing an existing action

Change-Id: Ie1ac0a8eb2c05403f4a926479f85cf79e85b8203
Reviewed-on: http://gerrit.dmdirc.com/845
Reviewed-by: Shane Mc Cormack <shane@dmdirc.com>
Automatic-Compile: DMDirc Local Commits <dmdirc@googlemail.com>

src/com/dmdirc/addons/ui_swing/components/validating/ValidatingJTextField.java

@@ -93,6 +93,16 @@ public class ValidatingJTextField extends JComponent implements DocumentListener
         textField.getDocument().addDocumentListener(this);
     }
 
+    /**
+     * Updates the validator for this textfield.
+     *
+     * @param validator new validator
+     */
+    public void setValidator(final Validator<String> validator) {
+        this.validator = validator;
+        checkError();
+    }
+
     /**
      * Checks the text for errors and sets the error state accordingly.
      */

src/com/dmdirc/addons/ui_swing/dialogs/actioneditor/ActionNamePanel.java

@@ -52,7 +52,7 @@ public class ActionNamePanel extends JPanel implements PropertyChangeListener {
      */
     private static final long serialVersionUID = 1;
     /** Original name. */
-    private final String originalName;
+    private String existingName;
     /** Action name field. */
     private ValidatingJTextField name;
     /** Action group. */
@@ -77,9 +77,9 @@ public class ActionNamePanel extends JPanel implements PropertyChangeListener {
         super();
 
         if (name == null) {
-            this.originalName = "";
+            this.existingName = "";
         } else {
-            this.originalName = name;
+            this.existingName = name;
         }
         this.group = ActionManager.getGroup(group);
 
@@ -92,10 +92,18 @@ public class ActionNamePanel extends JPanel implements PropertyChangeListener {
     /**
      * Sets the action name.
      * 
-     * @param name new name
+     * @param newName new name
      */
-    void setActionName(final String name) {
-        this.name.setText(name);
+    @SuppressWarnings("unchecked")
+    void setActionName(final String newName) {
+        if (newName == null) {
+            this.existingName = "";
+        } else {
+            this.existingName = newName;
+        }
+        name.setValidator(new ValidatorChain<String>(new FileNameValidator(),
+                new ActionNameValidator(group, existingName)));
+        this.name.setText(newName);
     }
 
     /** Validates the name. */
@@ -106,9 +114,9 @@ public class ActionNamePanel extends JPanel implements PropertyChangeListener {
     /** Initialises the components. */
     @SuppressWarnings("unchecked")
     private void initComponents() {
-        name = new ValidatingJTextField(new JTextField(originalName), 
+        name = new ValidatingJTextField(new JTextField(existingName),
                 new ValidatorChain<String>(new FileNameValidator(),
-                new ActionNameValidator(group)));
+                new ActionNameValidator(group, existingName)));
     }
 
     /** Adds the listeners. */
@@ -134,7 +142,7 @@ public class ActionNamePanel extends JPanel implements PropertyChangeListener {
 
      */
     public boolean hasNameChanged() {
-        return getActionName().equals(originalName);
+        return getActionName().equals(existingName);
     }
 
     /**