plugins/org.eclipse.oomph.ui/src/org/eclipse/oomph/internal/ui/FlatButton.java - oomph/org.eclipse.oomph - Git at Google

 /*
  * Copyright (c) 2015 The Eclipse Foundation 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:
  *    Yatta Solutions - [466264] initial API and implementation
  */
 package org.eclipse.oomph.internal.ui;

 import org.eclipse.oomph.ui.UIUtil;

 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.PaintEvent;
 import org.eclipse.swt.events.PaintListener;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.events.SelectionListener;
 import org.eclipse.swt.graphics.Color;
 import org.eclipse.swt.graphics.GC;
 import org.eclipse.swt.graphics.Image;
 import org.eclipse.swt.graphics.Point;
 import org.eclipse.swt.graphics.Rectangle;
 import org.eclipse.swt.layout.GridLayout;
 import org.eclipse.swt.widgets.Canvas;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Event;
 import org.eclipse.swt.widgets.Listener;

 import java.util.ArrayList;
 import java.util.List;

 /**
  * Special button that does not draw any borders on hover/down coming from the OS.
  *
  * @author Andreas Scharf
  */
 public class FlatButton extends Canvas implements Listener, PaintListener
 {
   private static final int DEFAULT_ICON_TEXT_GAP = 5;

   private static final Color COLOR_DEFAULT_DISABLED = UIPlugin.getColor(210, 210, 210);

   private final List<SelectionListener> selectionListeners = new ArrayList<SelectionListener>();

   private final int buttonStyle;

   private boolean hover;

   private Color hoverColor = UIUtil.COLOR_PURPLE;

   private Color disabledColor = COLOR_DEFAULT_DISABLED;

   private Image image;

   private String text;

   private int cornerWidth;

   private int iconTextGap = DEFAULT_ICON_TEXT_GAP;

   private int alignment = SWT.LEFT;

   private boolean listenersPaused;

   private boolean mouseDown;

   private boolean mouseLockedInBounds;

   private boolean showButtonDownState = true;

   public FlatButton(Composite parent, int buttonStyle)
   {
     super(parent, SWT.TRANSPARENT);
     this.buttonStyle = buttonStyle;

     setLayout(new GridLayout(1, false));
     setBackground(null);
     setCursor(UIUtil.getDisplay().getSystemCursor(SWT.CURSOR_HAND));

     hookListeners();
   }

   public void setText(String text)
   {
     if (this.text != text)
     {
       this.text = text;
       redraw();
     }
   }

   public void setImage(Image image)
   {
     if (this.image != image)
     {
       this.image = image;
       redraw();
     }
   }

   public Image getImage()
   {
     return image;
   }

   public void setAlignment(int alignment)
   {
     switch (alignment)
     {
       case SWT.LEFT:
       case SWT.CENTER:
       case SWT.RIGHT:
         // Do nothing.
         break;

       default:
         throw new IllegalArgumentException("Alignment must be one of SWT.LEFT, SWT.CENTER, SWT.RIGHT");
     }

     if (this.alignment != alignment)
     {
       this.alignment = alignment;
       redraw();
     }
   }

   public int getAlignment()
   {
     return alignment;
   }

   @Override
   public Point computeSize(int wHint, int hHint, boolean changed)
   {
     Point size = null;

     if (wHint != SWT.DEFAULT && hHint != SWT.DEFAULT)
     {
       size = new Point(wHint, hHint);
     }
     else
     {
       size = getTotalSize();
     }

     if (wHint != SWT.DEFAULT)
     {
       size.x = wHint;
     }

     if (hHint != SWT.DEFAULT)
     {
       size.y = hHint;
     }

     // Extend the size to be able to visualize button down state.
     size.x += 1;
     size.y += 1;

     return size;
   }

   protected Point getTotalSize()
   {
     int width = 0;
     int height = 0;
     if (text != null)
     {
       GC gc = new GC(this);
       Point textSize = gc.textExtent(text);
       width += textSize.x;

       if (image != null)
       {
         width += iconTextGap;
       }

       height += textSize.y;
     }

     if (image != null)
     {
       Rectangle imgBounds = image.getBounds();
       width += imgBounds.width;

       int heightDiff = imgBounds.height - height;
       if (heightDiff > 0)
       {
         height += heightDiff;
       }
     }

     return new Point(width, height);
   }

   protected void hookListeners()
   {
     addListener(SWT.MouseEnter, this);
     addListener(SWT.MouseExit, this);
     addListener(SWT.MouseDown, this);
     addListener(SWT.MouseUp, this);
     addListener(SWT.MouseMove, this);

     addPaintListener(this);
   }

   protected void unhookListeners()
   {
     removePaintListener(this);

     removeListener(SWT.MouseMove, (Listener)this);
     removeListener(SWT.MouseUp, (Listener)this);
     removeListener(SWT.MouseDown, (Listener)this);
     removeListener(SWT.MouseExit, (Listener)this);
     removeListener(SWT.MouseEnter, (Listener)this);
   }

   @Override
   public void dispose()
   {
     unhookListeners();
     super.dispose();
   }

   public void setIconTextGap(int iconTextGap)
   {
     if (this.iconTextGap != iconTextGap)
     {
       this.iconTextGap = iconTextGap;

       Composite parent = getParent();
       if (parent != null)
       {
         parent.layout();
       }
     }
   }

   /**
    * Called when this button should paint itself.
    *
    * Subclasses may implement.
    */
   protected void drawContent(PaintEvent e)
   {
     GC gc = e.gc;

     Point totalSize = getTotalSize();

     Rectangle clientArea = getClientArea();

     int startX = 0;

     switch (getAlignment())
     {
       case SWT.CENTER:
         startX = (clientArea.x + clientArea.width - totalSize.x) / 2;
         break;

       case SWT.RIGHT:
         startX = clientArea.x + clientArea.width - totalSize.x;
         break;
     }

     if (showButtonDownState && mouseLockedInBounds)
     {
       startX++;
     }

     if (image != null)
     {
       Rectangle imgBounds = image.getBounds();
       int imgY = (clientArea.y + clientArea.height - imgBounds.height) / 2;

       if (showButtonDownState && mouseLockedInBounds)
       {
         imgY++;
       }

       drawImage(gc, startX, imgY);

       startX += imgBounds.width;
       if (text != null)
       {
         startX += iconTextGap;
       }
     }

     if (text != null)
     {
       Point textExtent = gc.textExtent(text);
       int textY = (clientArea.y + clientArea.height - textExtent.y) / 2;

       if (showButtonDownState && mouseLockedInBounds)
       {
         textY += 1;
       }

       drawText(gc, startX, textY);
     }
   }

   protected void drawText(GC gc, int x, int y)
   {
     if (isEnabled())
     {
       if (isHover() && !listenersPaused && hoverColor != null)
       {
         gc.setForeground(hoverColor);
       }
     }
     else if (disabledColor != null)
     {
       gc.setForeground(disabledColor);
     }

     gc.drawText(text, x, y, true);
   }

   protected void drawImage(GC gc, int x, int y)
   {
     gc.drawImage(image, x, y);
   }

   @Override
   public int getStyle()
   {
     return buttonStyle;
   }

   @Override
   protected void checkSubclass()
   {
     // Allow subclassing.
   }

   public boolean isHover()
   {
     return hover;
   }

   public void setShowButtonDownState(boolean showButtonDownState)
   {
     if (this.showButtonDownState != showButtonDownState)
     {
       this.showButtonDownState = showButtonDownState;
       redraw();
     }
   }

   public void handleEvent(Event event)
   {
     switch (event.type)
     {
       case SWT.MouseEnter:
         onMouseEnter(event);
         break;

       case SWT.MouseUp:
         onMouseUp(event);
         break;

       case SWT.MouseExit:
         onMouseExit(event);
         break;

       case SWT.MouseDown:
         onMouseDown(event);
         break;

       case SWT.MouseMove:
         mouseMoveInternal(event);
     }

     if (!isDisposed())
     {
       redraw();
     }
   }

   private void mouseMoveInternal(Event event)
   {
     if (mouseDown)
     {
       Rectangle bounds = getBounds();
       boolean inBounds = event.x >= 0 && event.x <= bounds.width && event.y >= 0 && event.y <= bounds.height;
       if (inBounds != mouseLockedInBounds)
       {
         mouseLockedInBounds = inBounds;
         if (inBounds)
         {
           onMouseEnter(event);
         }
         else
         {
           onMouseExit(event);
         }
       }
     }
   }

   protected void onMouseDown(Event event)
   {
     mouseDown = true;
     mouseLockedInBounds = true;
   }

   protected void onMouseExit(Event event)
   {
     setHover(false);
   }

   protected void onMouseUp(Event event)
   {
     mouseLockedInBounds = false;
     mouseDown = false;
     setHover(true);
     notifySelectionListeners(new SelectionEvent(event));
   }

   protected void onMouseEnter(Event event)
   {
     setHover(true);
   }

   private void setHover(boolean hover)
   {
     if (this.hover != hover)
     {
       this.hover = hover;
       onHover();
     }
   }

   /**
    * Called when the hover status of this button changes.
    */
   protected void onHover()
   {
     // Subclasses may implement.
   }

   private void notifySelectionListeners(SelectionEvent event)
   {
     if (!isEnabled() || listenersPaused)
     {
       return;
     }

     Rectangle r = getBounds();
     if (event.x >= 0 && event.x <= r.width && event.y >= 0 && event.y <= r.height && !selectionListeners.isEmpty())
     {
       for (SelectionListener listener : selectionListeners)
       {
         try
         {
           listener.widgetSelected(event);
         }
         catch (Exception ex)
         {
           UIPlugin.INSTANCE.log(ex);
         }
       }
     }
   }

   protected boolean isListenersPaused()
   {
     return listenersPaused;
   }

   protected void setListenersPaused(boolean pause)
   {
     listenersPaused = pause;
   }

   public void setCornerWidth(int cornerWidth)
   {
     if (this.cornerWidth != cornerWidth)
     {
       this.cornerWidth = cornerWidth;
       redraw();
     }
   }

   public int getCornerWidth()
   {
     return cornerWidth;
   }

   public void addSelectionListener(SelectionListener listener)
   {
     selectionListeners.add(listener);
   }

   public void removeSelectionListener(SelectionListener listener)
   {
     selectionListeners.remove(selectionListeners);
   }

   public final void paintControl(PaintEvent e)
   {
     Rectangle clientBounds = getClientArea();
     GC gc = e.gc;
     gc.setAntialias(SWT.ON);
     int clientX = clientBounds.x;
     int clientY = clientBounds.y;

     int clientWidth = clientBounds.width - 1;
     int clientHeight = clientBounds.height - 1;

     if (showButtonDownState && mouseLockedInBounds)
     {
       clientX++;
       clientY++;
     }

     drawBackground(gc, clientX, clientY, clientWidth, clientHeight, 0, 0);
     drawContent(e);
     if (isHover())
     {
       drawHoverState(gc, clientX, clientY, clientWidth, clientHeight);
     }
   }

   protected void drawHoverState(GC gc, int x, int y, int width, int height)
   {
     // Subclasses may implement to draw a hover state.
   }

   @Override
   public void drawBackground(GC gc, int x, int y, int width, int height, int offsetX, int offsetY)
   {
     gc.fillRoundRectangle(x, y, width, height, cornerWidth, cornerWidth);
   }

   public Color getHoverColor()
   {
     return hoverColor;
   }

   public void setHoverColor(Color hoverColor)
   {
     if (this.hoverColor != hoverColor)
     {
       this.hoverColor = hoverColor;
       redraw();
     }
   }

   public Color getDisabledColor()
   {
     return disabledColor;
   }

   public void setDisabledColor(Color disabledColor)
   {
     if (this.disabledColor != disabledColor)
     {
       this.disabledColor = disabledColor;
       redraw();
     }
   }
 }
	/*
	* Copyright (c) 2015 The Eclipse Foundation 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:
	* Yatta Solutions - [466264] initial API and implementation
	*/
	package org.eclipse.oomph.internal.ui;

	import org.eclipse.oomph.ui.UIUtil;

	import org.eclipse.swt.SWT;
	import org.eclipse.swt.events.PaintEvent;
	import org.eclipse.swt.events.PaintListener;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.events.SelectionListener;
	import org.eclipse.swt.graphics.Color;
	import org.eclipse.swt.graphics.GC;
	import org.eclipse.swt.graphics.Image;
	import org.eclipse.swt.graphics.Point;
	import org.eclipse.swt.graphics.Rectangle;
	import org.eclipse.swt.layout.GridLayout;
	import org.eclipse.swt.widgets.Canvas;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Event;
	import org.eclipse.swt.widgets.Listener;

	import java.util.ArrayList;
	import java.util.List;

	/**
	* Special button that does not draw any borders on hover/down coming from the OS.
	*
	* @author Andreas Scharf
	*/
	public class FlatButton extends Canvas implements Listener, PaintListener
	{
	private static final int DEFAULT_ICON_TEXT_GAP = 5;

	private static final Color COLOR_DEFAULT_DISABLED = UIPlugin.getColor(210, 210, 210);

	private final List<SelectionListener> selectionListeners = new ArrayList<SelectionListener>();

	private final int buttonStyle;

	private boolean hover;

	private Color hoverColor = UIUtil.COLOR_PURPLE;

	private Color disabledColor = COLOR_DEFAULT_DISABLED;

	private Image image;

	private String text;

	private int cornerWidth;

	private int iconTextGap = DEFAULT_ICON_TEXT_GAP;

	private int alignment = SWT.LEFT;

	private boolean listenersPaused;

	private boolean mouseDown;

	private boolean mouseLockedInBounds;

	private boolean showButtonDownState = true;

	public FlatButton(Composite parent, int buttonStyle)
	{
	super(parent, SWT.TRANSPARENT);
	this.buttonStyle = buttonStyle;

	setLayout(new GridLayout(1, false));
	setBackground(null);
	setCursor(UIUtil.getDisplay().getSystemCursor(SWT.CURSOR_HAND));

	hookListeners();
	}

	public void setText(String text)
	{
	if (this.text != text)
	{
	this.text = text;
	redraw();
	}
	}

	public void setImage(Image image)
	{
	if (this.image != image)
	{
	this.image = image;
	redraw();
	}
	}

	public Image getImage()
	{
	return image;
	}

	public void setAlignment(int alignment)
	{
	switch (alignment)
	{
	case SWT.LEFT:
	case SWT.CENTER:
	case SWT.RIGHT:
	// Do nothing.
	break;

	default:
	throw new IllegalArgumentException("Alignment must be one of SWT.LEFT, SWT.CENTER, SWT.RIGHT");
	}

	if (this.alignment != alignment)
	{
	this.alignment = alignment;
	redraw();
	}
	}

	public int getAlignment()
	{
	return alignment;
	}

	@Override
	public Point computeSize(int wHint, int hHint, boolean changed)
	{
	Point size = null;

	if (wHint != SWT.DEFAULT && hHint != SWT.DEFAULT)
	{
	size = new Point(wHint, hHint);
	}
	else
	{
	size = getTotalSize();
	}

	if (wHint != SWT.DEFAULT)
	{
	size.x = wHint;
	}

	if (hHint != SWT.DEFAULT)
	{
	size.y = hHint;
	}

	// Extend the size to be able to visualize button down state.
	size.x += 1;
	size.y += 1;

	return size;
	}

	protected Point getTotalSize()
	{
	int width = 0;
	int height = 0;
	if (text != null)
	{
	GC gc = new GC(this);
	Point textSize = gc.textExtent(text);
	width += textSize.x;

	if (image != null)
	{
	width += iconTextGap;
	}

	height += textSize.y;
	}

	if (image != null)
	{
	Rectangle imgBounds = image.getBounds();
	width += imgBounds.width;

	int heightDiff = imgBounds.height - height;
	if (heightDiff > 0)
	{
	height += heightDiff;
	}
	}

	return new Point(width, height);
	}

	protected void hookListeners()
	{
	addListener(SWT.MouseEnter, this);
	addListener(SWT.MouseExit, this);
	addListener(SWT.MouseDown, this);
	addListener(SWT.MouseUp, this);
	addListener(SWT.MouseMove, this);

	addPaintListener(this);
	}

	protected void unhookListeners()
	{
	removePaintListener(this);

	removeListener(SWT.MouseMove, (Listener)this);
	removeListener(SWT.MouseUp, (Listener)this);
	removeListener(SWT.MouseDown, (Listener)this);
	removeListener(SWT.MouseExit, (Listener)this);
	removeListener(SWT.MouseEnter, (Listener)this);
	}

	@Override
	public void dispose()
	{
	unhookListeners();
	super.dispose();
	}

	public void setIconTextGap(int iconTextGap)
	{
	if (this.iconTextGap != iconTextGap)
	{
	this.iconTextGap = iconTextGap;

	Composite parent = getParent();
	if (parent != null)
	{
	parent.layout();
	}
	}
	}

	/**
	* Called when this button should paint itself.
	*
	* Subclasses may implement.
	*/
	protected void drawContent(PaintEvent e)
	{
	GC gc = e.gc;

	Point totalSize = getTotalSize();

	Rectangle clientArea = getClientArea();

	int startX = 0;

	switch (getAlignment())
	{
	case SWT.CENTER:
	startX = (clientArea.x + clientArea.width - totalSize.x) / 2;
	break;

	case SWT.RIGHT:
	startX = clientArea.x + clientArea.width - totalSize.x;
	break;
	}

	if (showButtonDownState && mouseLockedInBounds)
	{
	startX++;
	}

	if (image != null)
	{
	Rectangle imgBounds = image.getBounds();
	int imgY = (clientArea.y + clientArea.height - imgBounds.height) / 2;

	if (showButtonDownState && mouseLockedInBounds)
	{
	imgY++;
	}

	drawImage(gc, startX, imgY);

	startX += imgBounds.width;
	if (text != null)
	{
	startX += iconTextGap;
	}
	}

	if (text != null)
	{
	Point textExtent = gc.textExtent(text);
	int textY = (clientArea.y + clientArea.height - textExtent.y) / 2;

	if (showButtonDownState && mouseLockedInBounds)
	{
	textY += 1;
	}

	drawText(gc, startX, textY);
	}
	}

	protected void drawText(GC gc, int x, int y)
	{
	if (isEnabled())
	{
	if (isHover() && !listenersPaused && hoverColor != null)
	{
	gc.setForeground(hoverColor);
	}
	}
	else if (disabledColor != null)
	{
	gc.setForeground(disabledColor);
	}

	gc.drawText(text, x, y, true);
	}

	protected void drawImage(GC gc, int x, int y)
	{
	gc.drawImage(image, x, y);
	}

	@Override
	public int getStyle()
	{
	return buttonStyle;
	}

	@Override
	protected void checkSubclass()
	{
	// Allow subclassing.
	}

	public boolean isHover()
	{
	return hover;
	}

	public void setShowButtonDownState(boolean showButtonDownState)
	{
	if (this.showButtonDownState != showButtonDownState)
	{
	this.showButtonDownState = showButtonDownState;
	redraw();
	}
	}

	public void handleEvent(Event event)
	{
	switch (event.type)
	{
	case SWT.MouseEnter:
	onMouseEnter(event);
	break;

	case SWT.MouseUp:
	onMouseUp(event);
	break;

	case SWT.MouseExit:
	onMouseExit(event);
	break;

	case SWT.MouseDown:
	onMouseDown(event);
	break;

	case SWT.MouseMove:
	mouseMoveInternal(event);
	}

	if (!isDisposed())
	{
	redraw();
	}
	}

	private void mouseMoveInternal(Event event)
	{
	if (mouseDown)
	{
	Rectangle bounds = getBounds();
	boolean inBounds = event.x >= 0 && event.x <= bounds.width && event.y >= 0 && event.y <= bounds.height;
	if (inBounds != mouseLockedInBounds)
	{
	mouseLockedInBounds = inBounds;
	if (inBounds)
	{
	onMouseEnter(event);
	}
	else
	{
	onMouseExit(event);
	}
	}
	}
	}

	protected void onMouseDown(Event event)
	{
	mouseDown = true;
	mouseLockedInBounds = true;
	}

	protected void onMouseExit(Event event)
	{
	setHover(false);
	}

	protected void onMouseUp(Event event)
	{
	mouseLockedInBounds = false;
	mouseDown = false;
	setHover(true);
	notifySelectionListeners(new SelectionEvent(event));
	}

	protected void onMouseEnter(Event event)
	{
	setHover(true);
	}

	private void setHover(boolean hover)
	{
	if (this.hover != hover)
	{
	this.hover = hover;
	onHover();
	}
	}

	/**
	* Called when the hover status of this button changes.
	*/
	protected void onHover()
	{
	// Subclasses may implement.
	}

	private void notifySelectionListeners(SelectionEvent event)
	{
	if (!isEnabled() \|\| listenersPaused)
	{
	return;
	}

	Rectangle r = getBounds();
	if (event.x >= 0 && event.x <= r.width && event.y >= 0 && event.y <= r.height && !selectionListeners.isEmpty())
	{
	for (SelectionListener listener : selectionListeners)
	{
	try
	{
	listener.widgetSelected(event);
	}
	catch (Exception ex)
	{
	UIPlugin.INSTANCE.log(ex);
	}
	}
	}
	}

	protected boolean isListenersPaused()
	{
	return listenersPaused;
	}

	protected void setListenersPaused(boolean pause)
	{
	listenersPaused = pause;
	}

	public void setCornerWidth(int cornerWidth)
	{
	if (this.cornerWidth != cornerWidth)
	{
	this.cornerWidth = cornerWidth;
	redraw();
	}
	}

	public int getCornerWidth()
	{
	return cornerWidth;
	}

	public void addSelectionListener(SelectionListener listener)
	{
	selectionListeners.add(listener);
	}

	public void removeSelectionListener(SelectionListener listener)
	{
	selectionListeners.remove(selectionListeners);
	}

	public final void paintControl(PaintEvent e)
	{
	Rectangle clientBounds = getClientArea();
	GC gc = e.gc;
	gc.setAntialias(SWT.ON);
	int clientX = clientBounds.x;
	int clientY = clientBounds.y;

	int clientWidth = clientBounds.width - 1;
	int clientHeight = clientBounds.height - 1;

	if (showButtonDownState && mouseLockedInBounds)
	{
	clientX++;
	clientY++;
	}

	drawBackground(gc, clientX, clientY, clientWidth, clientHeight, 0, 0);
	drawContent(e);
	if (isHover())
	{
	drawHoverState(gc, clientX, clientY, clientWidth, clientHeight);
	}
	}

	protected void drawHoverState(GC gc, int x, int y, int width, int height)
	{
	// Subclasses may implement to draw a hover state.
	}

	@Override
	public void drawBackground(GC gc, int x, int y, int width, int height, int offsetX, int offsetY)
	{
	gc.fillRoundRectangle(x, y, width, height, cornerWidth, cornerWidth);
	}

	public Color getHoverColor()
	{
	return hoverColor;
	}

	public void setHoverColor(Color hoverColor)
	{
	if (this.hoverColor != hoverColor)
	{
	this.hoverColor = hoverColor;
	redraw();
	}
	}

	public Color getDisabledColor()
	{
	return disabledColor;
	}

	public void setDisabledColor(Color disabledColor)
	{
	if (this.disabledColor != disabledColor)
	{
	this.disabledColor = disabledColor;
	redraw();
	}
	}
	}