display.java

源码为Eclipse开源开发平台桌面开发工具SWT的源代码,

	int width = OS.GetSystemMetrics (OS.SM_CXVIRTUALSCREEN);
	int height = OS.GetSystemMetrics (OS.SM_CYVIRTUALSCREEN);
	return new Rectangle (x, y, width, height);
}

/**
 * Returns the display which the currently running thread is
 * the user-interface thread for, or null if the currently
 * running thread is not a user-interface thread for any display.
 *
 * @return the current display
 */
public static synchronized Display getCurrent () {
	return findDisplay (Thread.currentThread ());
}

/**
 * Returns a rectangle which describes the area of the
 * receiver which is capable of displaying data.
 * 
 * @return the client area
 *
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 *
 * @see #getBounds
 */
public Rectangle getClientArea () {
	checkDevice ();
	if (OS.GetSystemMetrics (OS.SM_CMONITORS) < 2) {
		RECT rect = new RECT ();
		OS.SystemParametersInfo (OS.SPI_GETWORKAREA, 0, rect, 0);
		int width = rect.right - rect.left;
		int height = rect.bottom - rect.top;
		return new Rectangle (rect.left, rect.top, width, height);
	}
	int x = OS.GetSystemMetrics (OS.SM_XVIRTUALSCREEN);
	int y = OS.GetSystemMetrics (OS.SM_YVIRTUALSCREEN);	
	int width = OS.GetSystemMetrics (OS.SM_CXVIRTUALSCREEN);
	int height = OS.GetSystemMetrics (OS.SM_CYVIRTUALSCREEN);
	return new Rectangle (x, y, width, height);
}

Control getControl (int handle) {
	if (handle == 0) return null;
	int index = OS.GetWindowLong (handle, OS.GWL_USERDATA) - 1;
	if (0 <= index && index < controlTable.length) {
		Control control = controlTable [index];
		/*
		* This code is intentionally commented.  It is possible
		* find the SWT control that is associated with a handle
		* that belongs to another process when the handle was
		* created by an in-proc OLE client.  In this case, the
		* handle comes from another process, but it is a child
		* of an SWT control.  For now, it is necessary to look
		* at handles that do not belong to the SWT process.
		*/
//		int [] hwndProcessId = new int [1];
//		int hwndThreadId = OS.GetWindowThreadProcessId (handle, hwndProcessId);
//		if (hwndProcessId [0] != processId || hwndThreadId != threadId) {
//			return null;
//		}

		/*
		* Because GWL_USERDATA can be used by native widgets that
		* do not belong to SWT, it is possible that GWL_USERDATA
		* could return an index that is in the range of the table,
		* but was not put there by SWT.  Therefore, it is necessary
		* to check the handle of the control that is in the table
		* against the handle that provided the GWL_USERDATA.
		* 
		* NOTE:  This check will not work in the case where the same
		* widget is registered multiple times with different handles.
		*/
		if (control != null && control.handle == handle) {
			return control;
		}
	}
	return null;
}

/**
 * Returns the control which the on-screen pointer is currently
 * over top of, or null if it is not currently over one of the
 * controls built by the currently running application.
 *
 * @return the control under the cursor
 *
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 */
public Control getCursorControl () {
	checkDevice ();
	POINT pt = new POINT ();
	if (!OS.GetCursorPos (pt)) return null;
	return findControl (OS.WindowFromPoint (pt));
}

/**
 * Returns the location of the on-screen pointer relative
 * to the top left corner of the screen.
 *
 * @return the cursor location
 *
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 */
public Point getCursorLocation () {
	checkDevice ();
	POINT pt = new POINT ();
	OS.GetCursorPos (pt);
	return new Point (pt.x, pt.y);
}

/**
 * Returns an array containing the recommended cursor sizes.
 *
 * @return the array of cursor sizes
 *
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 * 
 * @since 3.0
 */
public Point [] getCursorSizes () {
	checkDevice ();
	return new Point [] {
		new Point (OS.GetSystemMetrics (OS.SM_CXCURSOR), OS.GetSystemMetrics (OS.SM_CYCURSOR))};
}

/**
 * Returns the default display. One is created (making the
 * thread that invokes this method its user-interface thread)
 * if it did not already exist.
 *
 * @return the default display
 */
public static synchronized Display getDefault () {
	if (Default == null) Default = new Display ();
	return Default;
}

static boolean isValidClass (Class clazz) {
	String name = clazz.getName ();
	int index = name.lastIndexOf ('.');
	return name.substring (0, index + 1).equals (PACKAGE_PREFIX);
}

/**
 * Returns the application defined property of the receiver
 * with the specified name, or null if it has not been set.
 * <p>
 * Applications may have associated arbitrary objects with the
 * receiver in this fashion. If the objects stored in the
 * properties need to be notified when the display is disposed
 * of, it is the application's responsibility provide a
 * <code>disposeExec()</code> handler which does so.
 * </p>
 *
 * @param key the name of the property
 * @return the value of the property or null if it has not been set
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the key is null</li>
 * </ul>
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 *
 * @see #setData(String, Object)
 * @see #disposeExec(Runnable)
 */
public Object getData (String key) {
	checkDevice ();
	if (key == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (keys == null) return null;
	for (int i=0; i<keys.length; i++) {
		if (keys [i].equals (key)) return values [i];
	}
	return null;
}

/**
 * Returns the application defined, display specific data
 * associated with the receiver, or null if it has not been
 * set. The <em>display specific data</em> is a single,
 * unnamed field that is stored with every display. 
 * <p>
 * Applications may put arbitrary objects in this field. If
 * the object stored in the display specific data needs to
 * be notified when the display is disposed of, it is the
 * application's responsibility provide a
 * <code>disposeExec()</code> handler which does so.
 * </p>
 *
 * @return the display specific data
 *
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 *
 * @see #setData(Object)
 * @see #disposeExec(Runnable)
 */
public Object getData () {
	checkDevice ();
	return data;
}

/**
 * Returns the button dismissal alignment, one of <code>LEFT</code> or <code>RIGHT</code>.
 * The button dismissal alignment is the ordering that should be used when positioning the
 * default dismissal button for a dialog.  For example, in a dialog that contains an OK and
 * CANCEL button, on platforms where the button dismissal alignment is <code>LEFT</code>, the
 * button ordering should be OK/CANCEL.  When button dismissal alignment is <code>RIGHT</code>,
 * the button ordering should be CANCEL/OK.
 *
 * @return the button dismissal order
 *
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 * 
 * @since 2.1
 */
public int getDismissalAlignment () {
	checkDevice ();
	return SWT.LEFT;
}


/**
 * Returns the longest duration, in milliseconds, between
 * two mouse button clicks that will be considered a
 * <em>double click</em> by the underlying operating system.
 *
 * @return the double click time
 *
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 */
public int getDoubleClickTime () {
	checkDevice ();
	return OS.GetDoubleClickTime ();
}

/**
 * Returns the control which currently has keyboard focus,
 * or null if keyboard events are not currently going to
 * any of the controls built by the currently running
 * application.
 *
 * @return the control under the cursor
 *
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 */
public Control getFocusControl () {
	checkDevice ();
	return findControl (OS.GetFocus ());
}

/**
 * Returns true when the high contrast mode is enabled.
 * Otherwise, false is returned.
 * <p>
 * Note: This operation is a hint and is not supported on
 * platforms that do not have this concept.
 * </p>
 *
 * @return the high contrast mode
 *
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 * 
 * @since 3.0
 */
public boolean getHighContrast () {
	checkDevice ();
	if (OS.IsWinCE) return false;
	HIGHCONTRAST pvParam = new HIGHCONTRAST ();
	pvParam.cbSize = HIGHCONTRAST.sizeof;
	OS.SystemParametersInfo (OS.SPI_GETHIGHCONTRAST, 0, pvParam, 0);
	return (pvParam.dwFlags & OS.HCF_HIGHCONTRASTON) != 0;
}

/**
 * Returns the maximum allowed depth of icons on this display.
 * On some platforms, this may be different than the actual
 * depth of the display.
 *
 * @return the maximum icon depth
 *
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 */
public int getIconDepth () {
	checkDevice ();

	/* Use the character encoding for the default locale */
	TCHAR buffer1 = new TCHAR (0, "Control Panel\\Desktop\\WindowMetrics", true); //$NON-NLS-1$

	int [] phkResult = new int [1];
	int result = OS.RegOpenKeyEx (OS.HKEY_CURRENT_USER, buffer1, 0, OS.KEY_READ, phkResult);
	if (result != 0) return 4;
	int depth = 4;
	int [] lpcbData = {128};
	
	/* Use the character encoding for the default locale */
	TCHAR lpData = new TCHAR (0, lpcbData [0]);
	TCHAR buffer2 = new TCHAR (0, "Shell Icon BPP", true); //$NON-NLS-1$
	
	result = OS.RegQueryValueEx (phkResult [0], buffer2, 0, null, lpData, lpcbData);
	if (result == 0) {
		try {
			depth = Integer.parseInt (lpData.toString (0, lpData.strlen ()));
		} catch (NumberFormatException e) {}
	}
	OS.RegCloseKey (phkResult [0]);
	return depth;
}

/**
 * Returns an array containing the recommended icon sizes.
 *
 * @return the array of icon sizes
 *
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 * 
 * @see Decorations#setImages(Image[])
 * 
 * @since 3.0
 */
public Point [] getIconSizes () {
	checkDevice ();
	return new Point [] {
		new Point (OS.GetSystemMetrics (OS.SM_CXSMICON), OS.GetSystemMetrics (OS.SM_CYSMICON)),
		new Point (OS.GetSystemMetrics (OS.SM_CXICON), OS.GetSystemMetrics (OS.SM_CYICON))};	
}

ImageList getImageList (Point size) {
	if (imageList == null) imageList = new ImageList [4];
	
	int i = 0;
	int length = imageList.length; 
	while (i < length) {
		ImageList list = imageList [i];
		if (list == null) break;
		if (list.getImageSize().equals(size)) {
			list.addRef();
			return list;
		}
		i++;
	}
	
	if (i == length) {
		ImageList [] newList = new ImageList [length + 4];
		System.arraycopy (imageList, 0, newList, 0, length);
		imageList = newList;
	}
	
	ImageList list = new ImageList();
	imageList [i] = list;
	list.addRef();
	return list;
}

ImageList getToolImageList (Point size) {
	if (toolImageList == null) toolImageList = new ImageList [4];
	
	int i = 0;
	int length = toolImageList.length; 
	while (i < length) {
		ImageList list = toolImageList [i];
		if (list == null) break;
		if (list.getImageSize().equals(size)) {
			list.addRef();
			return list;
		}
		i++;
	}
	
	if (i == length) {
		ImageList [] newList = new ImageList [length + 4];
		System.arraycopy (toolImageList, 0, newList, 0, length);
		toolImageList = newList;
	}
	
	ImageList list = new ImageList();
	toolImageList [i] = list;
	list.addRef();
	return list;
}

ImageList getToolHotImageList (Point size) {
	if (toolHotImageList == null) toolHotImageList = new ImageList [4];
	
	int i = 0;
	int length = toolHotImageList.length; 
	while (i < length) {
		ImageList list = toolHotImageList [i];