--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dwt/custom/ControlEditor.d	Sat Aug 09 17:00:02 2008 +0200
@@ -0,0 +1,275 @@
+/*******************************************************************************
+ * Copyright (c) 2000, 2007 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     IBM Corporation - initial API and implementation
+ *     
+ * Port to the D Programming language:
+ *     Jacob Carlborg <jacob.carlborg@gmail.com>
+ *******************************************************************************/
+module dwt.custom.ControlEditor;
+
+import Math = tango.math.Math;
+
+import dwt.DWT;
+import dwt.graphics.Rectangle;
+import dwt.widgets.Composite;
+import dwt.widgets.Control;
+import dwt.widgets.Event;
+import dwt.widgets.Listener;
+import dwt.widgets.ScrollBar;
+
+/**
+ *
+ * A ControlEditor is a manager for a Control that appears above a composite and tracks with the
+ * moving and resizing of that composite.  It can be used to display one control above 
+ * another control.  This could be used when editing a control that does not have editing 
+ * capabilities by using a text editor or for launching a dialog by placing a button 
+ * above a control.
+ *
+ * <p> Here is an example of using a ControlEditor:
+ *
+ * <code><pre>
+ * Canvas canvas = new Canvas(shell, DWT.BORDER);
+ * canvas.setBounds(10, 10, 300, 300);  
+ * Color color = new Color(null, 255, 0, 0);
+ * canvas.setBackground(color);
+ * ControlEditor editor = new ControlEditor (canvas);
+ * // The editor will be a button in the bottom right corner of the canvas.
+ * // When selected, it will launch a Color dialog that will change the background 
+ * // of the canvas.
+ * Button button = new Button(canvas, DWT.PUSH);
+ * button.setText("Select Color...");
+ * button.addSelectionListener (new SelectionAdapter() {
+ *  public void widgetSelected(SelectionEvent e) {
+ *      ColorDialog dialog = new ColorDialog(shell);
+ *      dialog.open();
+ *      RGB rgb = dialog.getRGB();
+ *      if (rgb !is null) {
+ *          if (color !is null) color.dispose();
+ *          color = new Color(null, rgb);
+ *          canvas.setBackground(color);
+ *      }
+ *      
+ *  }
+ * });
+ *
+ * editor.horizontalAlignment = DWT.RIGHT;
+ * editor.verticalAlignment = DWT.BOTTOM;
+ * editor.grabHorizontal = false;
+ * editor.grabVertical = false;
+ * Point size = button.computeSize(DWT.DEFAULT, DWT.DEFAULT);
+ * editor.minimumWidth = size.x;
+ * editor.minimumHeight = size.y;
+ * editor.setEditor (button);
+ * </pre></code>
+ */
+public class ControlEditor {
+
+    /**
+     * Specifies how the editor should be aligned relative to the control.  Allowed values
+     * are DWT.LEFT, DWT.RIGHT and DWT.CENTER.  The default value is DWT.CENTER.
+     */
+    public int horizontalAlignment = DWT.CENTER;
+
+    /**
+     * Specifies whether the editor should be sized to use the entire width of the control.
+     * True means resize the editor to the same width as the cell.  False means do not adjust 
+     * the width of the editor. The default value is false.
+     */
+    public bool grabHorizontal = false;
+
+    /**
+     * Specifies the minimum width the editor can have.  This is used in association with
+     * a true value of grabHorizontal.  If the cell becomes smaller than the minimumWidth, the 
+     * editor will not made smaller than the minimum width value.  The default value is 0.
+     */
+    public int minimumWidth = 0;
+
+    /**
+     * Specifies how the editor should be aligned relative to the control.  Allowed values
+     * are DWT.TOP, DWT.BOTTOM and DWT.CENTER.  The default value is DWT.CENTER.
+     */
+    public int verticalAlignment = DWT.CENTER;
+
+    /**
+     * Specifies whether the editor should be sized to use the entire height of the control.
+     * True means resize the editor to the same height as the underlying control.  False means do not adjust 
+     * the height of the editor.    The default value is false.
+     */
+    public bool grabVertical = false;
+
+    /**
+     * Specifies the minimum height the editor can have.  This is used in association with
+     * a true value of grabVertical.  If the control becomes smaller than the minimumHeight, the 
+     * editor will not made smaller than the minimum height value.  The default value is 0.
+     */
+    public int minimumHeight = 0;
+
+    Composite parent;
+    Control editor;
+    private bool hadFocus;
+    private Listener controlListener;
+    private Listener scrollbarListener;
+
+    private const static int[] EVENTS = [DWT.KeyDown, DWT.KeyUp, DWT.MouseDown, DWT.MouseUp, DWT.Resize];
+
+    /**
+     * Creates a ControlEditor for the specified Composite.
+     *
+     * @param parent the Composite above which this editor will be displayed
+     *
+     */
+    public this (Composite parent) {
+        this.parent = parent;
+
+        controlListener = new class Listener {
+            public void handleEvent (Event e) {
+                layout();
+            }
+        };
+        for (int i = 0; i < EVENTS.length; i++) {
+            parent.addListener(EVENTS[i], controlListener);
+        }
+
+        scrollbarListener = new class Listener {
+            public void handleEvent (Event e) {
+                scroll(e);
+            }
+        };
+        ScrollBar hBar = parent.getHorizontalBar();
+        if (hBar !is null)
+            hBar.addListener(DWT.Selection, scrollbarListener);
+        ScrollBar vBar = parent.getVerticalBar();
+        if (vBar !is null)
+            vBar.addListener(DWT.Selection, scrollbarListener);
+    }
+
+    Rectangle computeBounds () {
+        Rectangle clientArea = parent.getClientArea();
+        Rectangle editorRect = new Rectangle(clientArea.x, clientArea.y, minimumWidth, minimumHeight);
+
+        if (grabHorizontal)
+            editorRect.width = Math.max(clientArea.width, minimumWidth);
+
+        if (grabVertical)
+            editorRect.height = Math.max(clientArea.height, minimumHeight);
+
+        switch (horizontalAlignment) {
+            case DWT.RIGHT:
+                editorRect.x += clientArea.width - editorRect.width;
+            break;
+            case DWT.LEFT:
+            // do nothing - clientArea.x is the right answer
+            break;
+            default:
+                // default is CENTER
+                editorRect.x += (clientArea.width - editorRect.width) / 2;
+        }
+
+        switch (verticalAlignment) {
+            case DWT.BOTTOM:
+                editorRect.y += clientArea.height - editorRect.height;
+            break;
+            case DWT.TOP:
+            // do nothing - clientArea.y is the right answer
+            break;
+            default:
+                // default is CENTER
+                editorRect.y += (clientArea.height - editorRect.height) / 2;
+        }
+
+        return editorRect;
+
+    }
+
+    /**
+     * Removes all associations between the Editor and the underlying composite.  The
+     * composite and the editor Control are <b>not</b> disposed.
+     */
+    public void dispose () {
+        if (parent !is null && !parent.isDisposed()) {
+            for (int i = 0; i < EVENTS.length; i++) {
+                parent.removeListener(EVENTS[i], controlListener);
+            }
+            ScrollBar hBar = parent.getHorizontalBar();
+            if (hBar !is null)
+                hBar.removeListener(DWT.Selection, scrollbarListener);
+            ScrollBar vBar = parent.getVerticalBar();
+            if (vBar !is null)
+                vBar.removeListener(DWT.Selection, scrollbarListener);
+        }
+
+        parent = null;
+        editor = null;
+        hadFocus = false;
+        controlListener = null;
+        scrollbarListener = null;
+    }
+
+    /**
+     * Returns the Control that is displayed above the composite being edited.
+     *
+     * @return the Control that is displayed above the composite being edited
+     */
+    public Control getEditor () {
+        return editor;
+    }
+
+    /**
+     * Lays out the control within the underlying composite.  This
+     * method should be called after changing one or more fields to
+     * force the Editor to resize.
+     * 
+     * @since 2.1
+     */
+    public void layout () {
+        if (editor is null || editor.isDisposed())
+            return;
+        if (editor.getVisible()) {
+            hadFocus = editor.isFocusControl();
+        } // this doesn't work because
+        // resizing the column takes the focus away
+        // before we get here
+        editor.setBounds(computeBounds());
+        if (hadFocus) {
+            if (editor is null || editor.isDisposed())
+                return;
+            editor.setFocus();
+        }
+    }
+
+    void scroll (Event e) {
+        if (editor is null || editor.isDisposed())
+            return;
+        layout();
+    }
+
+    /**
+     * Specify the Control that is to be displayed.
+     *
+     * <p>Note: The Control provided as the editor <b>must</b> be created with its parent 
+     * being the Composite specified in the ControlEditor constructor.
+     * 
+     * @param editor the Control that is displayed above the composite being edited
+     */
+    public void setEditor (Control editor) {
+
+        if (editor is null) {
+            // this is the case where the caller is setting the editor to be blank
+            // set all the values accordingly
+            this.editor = null;
+            return;
+        }
+
+        this.editor = editor;
+        layout();
+        if (this.editor is null || this.editor.isDisposed())
+            return;
+        editor.setVisible(true);
+    }
+}