| /******************************************************************************* |
| * Copyright (c) 2000, 2003 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Common Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/cpl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.swt.widgets; |
| |
| |
| import org.eclipse.swt.*; |
| import org.eclipse.swt.internal.gtk.*; |
| import org.eclipse.swt.graphics.*; |
| import org.eclipse.swt.events.*; |
| |
| /** |
| * Instances of this class implement rubber banding rectangles that are |
| * drawn onto a parent <code>Composite</code> or <code>Display</code>. |
| * These rectangles can be specified to respond to mouse and key events |
| * by either moving or resizing themselves accordingly. Trackers are |
| * typically used to represent window geometries in a lightweight manner. |
| * |
| * <dl> |
| * <dt><b>Styles:</b></dt> |
| * <dd>LEFT, RIGHT, UP, DOWN, RESIZE</dd> |
| * <dt><b>Events:</b></dt> |
| * <dd>Move, Resize</dd> |
| * </dl> |
| * <p> |
| * Note: Rectangle move behavior is assumed unless RESIZE is specified. |
| * </p><p> |
| * IMPORTANT: This class is <em>not</em> intended to be subclassed. |
| * </p> |
| */ |
| public class Tracker extends Widget { |
| Composite parent; |
| Display display; |
| int cursor, lastCursor; |
| boolean tracking, stippled; |
| Rectangle [] rectangles = new Rectangle [0]; |
| int xWindow; |
| int ptrGrabResult; |
| |
| |
| /** |
| * Constructs a new instance of this class given its parent |
| * and a style value describing its behavior and appearance. |
| * <p> |
| * The style value is either one of the style constants defined in |
| * class <code>SWT</code> which is applicable to instances of this |
| * class, or must be built by <em>bitwise OR</em>'ing together |
| * (that is, using the <code>int</code> "|" operator) two or more |
| * of those <code>SWT</code> style constants. The class description |
| * lists the style constants that are applicable to the class. |
| * Style bits are also inherited from superclasses. |
| * </p> |
| * |
| * @param parent a widget which will be the parent of the new instance (cannot be null) |
| * @param style the style of widget to construct |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_NULL_ARGUMENT - if the parent is null</li> |
| * </ul> |
| * @exception SWTException <ul> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li> |
| * <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li> |
| * </ul> |
| * |
| * @see SWT#LEFT |
| * @see SWT#RIGHT |
| * @see SWT#UP |
| * @see SWT#DOWN |
| * @see SWT#RESIZE |
| * @see Widget#checkSubclass |
| * @see Widget#getStyle |
| */ |
| public Tracker (Composite parent, int style) { |
| super (parent, checkStyle(style)); |
| this.parent = parent; |
| display = parent.getDisplay (); |
| xWindow = calculateWindow(); |
| } |
| |
| /** |
| * Constructs a new instance of this class given the display |
| * to create it on and a style value describing its behavior |
| * and appearance. |
| * <p> |
| * The style value is either one of the style constants defined in |
| * class <code>SWT</code> which is applicable to instances of this |
| * class, or must be built by <em>bitwise OR</em>'ing together |
| * (that is, using the <code>int</code> "|" operator) two or more |
| * of those <code>SWT</code> style constants. The class description |
| * lists the style constants that are applicable to the class. |
| * Style bits are also inherited from superclasses. |
| * </p><p> |
| * Note: Currently, null can be passed in for the display argument. |
| * This has the effect of creating the tracker on the currently active |
| * display if there is one. If there is no current display, the |
| * tracker is created on a "default" display. <b>Passing in null as |
| * the display argument is not considered to be good coding style, |
| * and may not be supported in a future release of SWT.</b> |
| * </p> |
| * |
| * @param display the display to create the tracker on |
| * @param style the style of control to construct |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li> |
| * <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li> |
| * </ul> |
| * |
| * @see SWT#LEFT |
| * @see SWT#RIGHT |
| * @see SWT#UP |
| * @see SWT#DOWN |
| */ |
| public Tracker (Display display, int style) { |
| if (display == null) display = Display.getCurrent (); |
| if (display == null) display = Display.getDefault (); |
| if (!display.isValidThread ()) { |
| error (SWT.ERROR_THREAD_INVALID_ACCESS); |
| } |
| this.style = checkStyle (style); |
| this.display = display; |
| xWindow = calculateWindow(); |
| } |
| |
| |
| /* |
| * === ADD / REMOVE LISTENERS === |
| */ |
| |
| /** |
| * Adds the listener to the collection of listeners who will |
| * be notified when the control is moved or resized, by sending |
| * it one of the messages defined in the <code>ControlListener</code> |
| * interface. |
| * |
| * @param listener the listener which should be notified |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_NULL_ARGUMENT - if the listener is null</li> |
| * </ul> |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| * |
| * @see ControlListener |
| * @see #removeControlListener |
| */ |
| public void addControlListener(ControlListener listener) { |
| checkWidget(); |
| if (listener == null) error (SWT.ERROR_NULL_ARGUMENT); |
| TypedListener typedListener = new TypedListener (listener); |
| addListener (SWT.Move,typedListener); |
| } |
| |
| /** |
| * Removes the listener from the collection of listeners who will |
| * be notified when the control is moved or resized. |
| * |
| * @param listener the listener which should be notified |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_NULL_ARGUMENT - if the listener is null</li> |
| * </ul> |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| * |
| * @see ControlListener |
| * @see #addControlListener |
| */ |
| public void removeControlListener (ControlListener listener) { |
| checkWidget(); |
| if (listener == null) error (SWT.ERROR_NULL_ARGUMENT); |
| if (eventTable == null) return; |
| eventTable.unhook (SWT.Move, listener); |
| } |
| |
| |
| |
| |
| /* |
| * === PUBLIC ACCESSORS === |
| */ |
| |
| public Display getDisplay () { |
| return display; |
| } |
| |
| /** |
| * Returns the bounds that are being drawn, expressed relative to the parent |
| * widget. If the parent is a <code>Display</code> then these are screen |
| * coordinates. |
| * |
| * @return the bounds of the Rectangles being drawn |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public Rectangle [] getRectangles () { |
| checkWidget(); |
| return rectangles; |
| } |
| |
| /** |
| * Returns <code>true</code> if the rectangles are drawn with a stippled line, <code>false</code> otherwise. |
| * |
| * @return the stippled effect of the rectangles |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public boolean getStippled () { |
| checkWidget(); |
| return stippled; |
| } |
| |
| /** |
| * Specifies the rectangles that should be drawn, expressed relative to the parent |
| * widget. If the parent is a Display then these are screen coordinates. |
| * |
| * @param rectangles the bounds of the rectangles to be drawn |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public void setRectangles (Rectangle [] rectangles) { |
| checkWidget(); |
| this.rectangles = rectangles; |
| } |
| |
| /** |
| * Changes the appearance of the line used to draw the rectangles. |
| * |
| * @param stippled <code>true</code> if rectangle should appear stippled |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public void setStippled (boolean stippled) { |
| checkWidget(); |
| this.stippled = stippled; |
| } |
| |
| |
| |
| /* |
| * === PUBLIC FUNCTIONALITY === |
| */ |
| |
| /** |
| * Stops displaying the tracker rectangles. Note that this is not considered |
| * to be a cancelation by the user. |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public void close () { |
| checkWidget(); |
| tracking = false; |
| } |
| |
| /** |
| * Displays the Tracker rectangles for manipulation by the user. Returns when |
| * the user has either finished manipulating the rectangles or has cancelled the |
| * Tracker. |
| * |
| * @return <code>true</code> if the user did not cancel the Tracker, <code>false</code> otherwise |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public boolean open () { |
| checkWidget(); |
| boolean cancelled=false; |
| tracking = true; |
| drawRectangles (); |
| |
| int[] newX = new int[1]; |
| int[] newY = new int[1]; |
| int[] oldX = new int[1]; |
| int[] oldY = new int[1]; |
| OS.gdk_window_get_pointer(xWindow, oldX,oldY, null); |
| grab(); |
| |
| /* |
| * Tracker behaves like a Dialog with its own OS event loop. |
| */ |
| while (tracking) { |
| if (parent != null && parent.isDisposed ()) break; |
| // wait for an event |
| int eventPtr; |
| while (true) { |
| eventPtr = OS.gdk_event_get(); |
| if (eventPtr != 0) { |
| break; |
| } |
| else { |
| try { Thread.sleep(50); } catch (Exception ex) {} |
| } |
| } |
| |
| GdkEvent osEvent = new GdkEvent(); |
| OS.memmove(osEvent, eventPtr, GdkEvent.sizeof); |
| int eventType = osEvent.type; |
| switch (eventType) { |
| case OS.GDK_BUTTON_RELEASE: |
| case OS.GDK_MOTION_NOTIFY: |
| if (cursor != lastCursor) { ungrab(); grab(); } |
| OS.gdk_window_get_pointer(xWindow, newX,newY, null); |
| if (oldX [0] != newX [0] || oldY [0] != newY [0]) { |
| drawRectangles (); |
| for (int i=0; i<rectangles.length; i++) { |
| rectangles [i].x += newX [0] - oldX [0]; |
| rectangles [i].y += newY [0] - oldY [0]; |
| } |
| Event event = new Event(); |
| event.x = newX[0]; |
| event.y = newY[0]; |
| sendEvent (SWT.Move,event); |
| drawRectangles (); |
| oldX [0] = newX [0]; oldY [0] = newY [0]; |
| } |
| tracking = (eventType != OS.GDK_BUTTON_RELEASE); |
| break; |
| case OS.GDK_KEY_PRESS: |
| GdkEventKey gdkEvent = new GdkEventKey (); |
| OS.memmove (gdkEvent, eventPtr, GdkEventKey.sizeof); |
| switch (gdkEvent.keyval) { |
| case OS.GDK_Escape: |
| cancelled = true; |
| // fallthrough |
| case OS.GDK_Return: |
| tracking = false; |
| break; |
| } |
| break; |
| } // switch |
| OS.gdk_event_free(eventPtr); |
| } // while |
| drawRectangles(); |
| ungrab(); |
| return !cancelled; |
| } |
| |
| private void drawRectangles () { |
| if (parent != null) { |
| if (parent.isDisposed ()) return; |
| parent.getShell ().update (); |
| } else { |
| display.update (); |
| } |
| |
| int gc = OS.gdk_gc_new(xWindow); |
| if (gc==0) error(SWT.ERROR_UNSPECIFIED); |
| |
| /* White foreground */ |
| int colormap = OS.gdk_colormap_get_system(); |
| GdkColor color = new GdkColor(); |
| OS.gdk_color_white(colormap, color); |
| OS.gdk_gc_set_foreground(gc, color); |
| |
| /* Draw on top of inferior widgets */ |
| OS.gdk_gc_set_subwindow(gc, OS.GDK_INCLUDE_INFERIORS); |
| |
| /* XOR */ |
| OS.gdk_gc_set_function(gc, OS.GDK_XOR); |
| |
| for (int i=0; i<rectangles.length; i++) { |
| Rectangle rect = rectangles [i]; |
| OS.gdk_draw_rectangle(xWindow, gc, 0, rect.x, rect.y, rect.width, rect.height); |
| } |
| OS.g_object_unref(gc); |
| } |
| |
| /* |
| * Figure which GdkWindow we'll draw on. |
| * That's normally the root X window, or the parent's GdkWindow if we have a parent. |
| */ |
| private int calculateWindow() { |
| int answer; |
| if (parent == null) answer = OS.GDK_ROOT_PARENT(); |
| else answer = OS.GTK_WIDGET_WINDOW(parent.paintHandle()); |
| if (answer==0) error(SWT.ERROR_UNSPECIFIED); |
| return answer; |
| } |
| |
| /** |
| * Sets the <code>Cursor</code> of the Tracker. If this cursor is <code>null</code> |
| * then the cursor reverts to the default. |
| * |
| * @param newCursor the new <code>Cursor</code> to display |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public void setCursor (Cursor value) { |
| checkWidget (); |
| cursor = 0; |
| if (value != null) cursor = value.handle; |
| } |
| void grab() { |
| ptrGrabResult = OS.gdk_pointer_grab(xWindow, |
| false, |
| OS.GDK_POINTER_MOTION_MASK | OS.GDK_BUTTON_RELEASE_MASK, |
| xWindow, |
| cursor, |
| OS.GDK_CURRENT_TIME); |
| lastCursor = cursor; |
| } |
| void ungrab() { |
| if (ptrGrabResult == OS.GDK_GRAB_SUCCESS) |
| OS.gdk_pointer_ungrab(OS.GDK_CURRENT_TIME); |
| |
| } |
| static int checkStyle (int style) { |
| if ((style & (SWT.LEFT | SWT.RIGHT | SWT.UP | SWT.DOWN)) == 0) { |
| style |= SWT.LEFT | SWT.RIGHT | SWT.UP | SWT.DOWN; |
| } |
| return style; |
| } |
| } |