/*******************************************************************************
* Copyright (c) 2000, 2013 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
*******************************************************************************/
package org.eclipse.swt.graphics;
import org.eclipse.swt.SWT;
import org.eclipse.swt.SWTException;
import org.eclipse.swt.widgets.Display;
/**
* This class is the abstract superclass of all device objects, such as the
* Display device and the Printer device. Devices can have a graphics context
* (GC) created for them, and they can be drawn on by sending messages to the
* associated GC.
*
* @see <a href="http://www.eclipse.org/swt/">Sample code and further
* information</a>
*/
public abstract class Device implements Drawable {
public static boolean DEBUG;
private boolean disposed;
boolean tracking = false;
/**
* Constructs a new instance of this class.
* <p>
* You must dispose the device when it is no longer required.
* </p>
*
* @see #create
* @see #init
*
* @since 3.1
*/
public Device() {
// TODO
}
/**
* Constructs a new instance of this class.
* <p>
* You must dispose the device when it is no longer required.
* </p>
*
* @param data
* the DeviceData which describes the receiver
*
* @see #create
* @see #init
* @see DeviceData
*/
public Device(DeviceData data) {
// TODO
}
/*
* TEMPORARY CODE. When a graphics object is created and the device
* parameter is null, the current Display is used. This presents a problem
* because SWT graphics does not reference classes in SWT widgets. The
* correct fix is to remove this feature. Unfortunately, too many
* application programs rely on this feature.
*/
protected static Device CurrentDevice;
protected static Runnable DeviceFinder;
static {
try {
Class.forName("org.eclipse.swt.widgets.Display");
} catch (ClassNotFoundException e) {
}
}
/*
* TEMPORARY CODE.
*/
static synchronized Device getDevice() {
if (DeviceFinder != null)
DeviceFinder.run();
Device device = CurrentDevice;
CurrentDevice = null;
return device;
}
/**
* Throws an <code>SWTException</code> if the receiver can not be accessed
* by the caller. This may include both checks on the state of the receiver
* and more generally on the entire execution context. This method
* <em>should</em> be called by device implementors to enforce the standard
* SWT invariants.
* <p>
* Currently, it is an error to invoke any method (other than
* <code>isDisposed()</code> and <code>dispose()</code>) on a device that
* has had its <code>dispose()</code> method called.
* </p>
* <p>
* In future releases of SWT, there may be more or fewer error checks and
* exceptions may be thrown for different reasons.
* <p>
*
* @exception SWTException
* <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been
* disposed</li>
* </ul>
*/
protected void checkDevice() {
if (disposed)
SWT.error(SWT.ERROR_DEVICE_DISPOSED);
}
/**
* Creates the device in the operating system. If the device does not have a
* handle, this method may do nothing depending on the device.
* <p>
* This method is called before <code>init</code>.
* </p>
* <p>
* Subclasses are supposed to reimplement this method and not call the
* <code>super</code> implementation.
* </p>
*
* @param data
* the DeviceData which describes the receiver
*
* @see #init
*/
protected void create(DeviceData data) {
// TODO
}
/**
* Disposes of the operating system resources associated with the receiver.
* After this method has been invoked, the receiver will answer
* <code>true</code> when sent the message <code>isDisposed()</code>.
*
* @see #release
* @see #destroy
* @see #checkDevice
*/
public void dispose() {
// TODO
}
void dispose_Object(Object object) {
// TODO
}
/**
* Destroys the device in the operating system and releases the device's
* handle. If the device does not have a handle, this method may do nothing
* depending on the device.
* <p>
* This method is called after <code>release</code>.
* </p>
* <p>
* Subclasses are supposed to reimplement this method and not call the
* <code>super</code> implementation.
* </p>
*
* @see #dispose
* @see #release
*/
protected void destroy() {
// TODO
}
/**
* Returns a rectangle describing the receiver's size and location.
*
* @return the bounding rectangle
*
* @exception SWTException
* <ul>
* <li>ERROR_DEVICE_DISPOSED - if the receiver has been
* disposed</li>
* </ul>
*/
public Rectangle getBounds() {
checkDevice();
// TODO
return new Rectangle(0, 0, 0, 0);
}
/**
* Returns a <code>DeviceData</code> based on the receiver. Modifications
* made to this <code>DeviceData</code> will not affect the receiver.
*
* @return a <code>DeviceData</code> containing the device's data and
* attributes
*
* @exception SWTException
* <ul>
* <li>ERROR_DEVICE_DISPOSED - if the receiver has been
* disposed</li>
* </ul>
*
* @see DeviceData
*/
public DeviceData getDeviceData() {
checkDevice();
DeviceData data = new DeviceData();
// TODO
return data;
}
/**
* 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_DEVICE_DISPOSED - if the receiver has been
* disposed</li>
* </ul>
*
* @see #getBounds
*/
public Rectangle getClientArea() {
checkDevice();
// TODO
return getBounds();
}
/**
* Returns the bit depth of the screen, which is the number of bits it takes
* to represent the number of unique colors that the screen is currently
* capable of displaying. This number will typically be one of 1, 8, 15, 16,
* 24 or 32.
*
* @return the depth of the screen
*
* @exception SWTException
* <ul>
* <li>ERROR_DEVICE_DISPOSED - if the receiver has been
* disposed</li>
* </ul>
*/
public int getDepth() {
checkDevice();
// TODO
return 0;
}
/**
* Returns a point whose x coordinate is the horizontal dots per inch of the
* display, and whose y coordinate is the vertical dots per inch of the
* display.
*
* @return the horizontal and vertical DPI
*
* @exception SWTException
* <ul>
* <li>ERROR_DEVICE_DISPOSED - if the receiver has been
* disposed</li>
* </ul>
*/
public Point getDPI() {
checkDevice();
// TODO
return new Point(0, 0);
}
/**
* Returns <code>FontData</code> objects which describe the fonts that match
* the given arguments. If the <code>faceName</code> is null, all fonts will
* be returned.
*
* @param faceName
* the name of the font to look for, or null
* @param scalable
* if true only scalable fonts are returned, otherwise only
* non-scalable fonts are returned.
* @return the matching font data
*
* @exception SWTException
* <ul>
* <li>ERROR_DEVICE_DISPOSED - if the receiver has been
* disposed</li>
* </ul>
*/
public FontData[] getFontList(String faceName, boolean scalable) {
checkDevice();
// TODO
return new FontData[0];
}
/**
* Returns the matching standard color for the given constant, which should
* be one of the color constants specified in class <code>SWT</code>. Any
* value other than one of the SWT color constants which is passed in will
* result in the color black. This color should not be freed because it was
* allocated by the system, not the application.
*
* @param id
* the color constant
* @return the matching color
*
* @exception SWTException
* <ul>
* <li>ERROR_DEVICE_DISPOSED - if the receiver has been
* disposed</li>
* </ul>
*
* @see SWT
*/
public Color getSystemColor(int id) {
// TODO
return new Color(this, 0, 0, 0);
}
/**
* Returns a reasonable font for applications to use. On some platforms,
* this will match the "default font" or "system font" if such can be found.
* This font should not be freed because it was allocated by the system, not
* the application.
* <p>
* Typically, applications which want the default look should simply not set
* the font on the widgets they create. Widgets are always created with the
* correct default font for the class of user-interface component they
* represent.
* </p>
*
* @return a font
*
* @exception SWTException
* <ul>
* <li>ERROR_DEVICE_DISPOSED - if the receiver has been
* disposed</li>
* </ul>
*/
public Font getSystemFont() {
// TODO
return new Font(Display.getDefault(), new FontData());
}
/**
* Returns <code>true</code> if the underlying window system prints out
* warning messages on the console, and <code>setWarnings</code> had
* previously been called with <code>true</code>.
*
* @return <code>true</code>if warnings are being handled, and
* <code>false</code> otherwise
*
* @exception SWTException
* <ul>
* <li>ERROR_DEVICE_DISPOSED - if the receiver has been
* disposed</li>
* </ul>
*/
public boolean getWarnings() {
checkDevice();
// TODO
return false;
}
/**
* Initializes any internal resources needed by the device.
* <p>
* This method is called after <code>create</code>.
* </p>
* <p>
* If subclasses reimplement this method, they must call the
* <code>super</code> implementation.
* </p>
*
* @see #create
*/
protected void init() {
// TODO
}
/**
* Invokes platform specific functionality to allocate a new GC handle.
* <p>
* <b>IMPORTANT:</b> This method is <em>not</em> part of the public API for
* <code>Device</code>. It is marked public only so that it can be shared
* within the packages provided by SWT. It is not available on all
* platforms, and should never be called from application code.
* </p>
*
* @param data
* the platform specific GC data
* @return the platform specific GC handle
*
* @noreference This method is not intended to be referenced by clients.
*/
public abstract long /* int */internal_new_GC(GCData data);
/**
* Invokes platform specific functionality to dispose a GC handle.
* <p>
* <b>IMPORTANT:</b> This method is <em>not</em> part of the public API for
* <code>Device</code>. It is marked public only so that it can be shared
* within the packages provided by SWT. It is not available on all
* platforms, and should never be called from application code.
* </p>
*
* @param hDC
* the platform specific GC handle
* @param data
* the platform specific GC data
*
* @noreference This method is not intended to be referenced by clients.
*/
public abstract void internal_dispose_GC(long /* int */hDC, GCData data);
/**
* Returns <code>true</code> if the device has been disposed, and
* <code>false</code> otherwise.
* <p>
* This method gets the dispose state for the device. When a device has been
* disposed, it is an error to invoke any other method using the device.
*
* @return <code>true</code> when the device is disposed and
* <code>false</code> otherwise
*/
public boolean isDisposed() {
synchronized (Device.class) {
return disposed;
}
}
/**
* Loads the font specified by a file. The font will be present in the list
* of fonts available to the application.
*
* @param path
* the font file path
* @return whether the font was successfully loaded
*
* @exception SWTException
* <ul>
* <li>ERROR_NULL_ARGUMENT - if path is null</li>
* <li>ERROR_DEVICE_DISPOSED - if the receiver has been
* disposed</li>
* </ul>
*
* @see Font
*
* @since 3.3
*/
public boolean loadFont(String path) {
checkDevice();
// TODO
return false;
}
void new_Object(Object object) {
// TODO
}
/**
* Releases any internal resources back to the operating system and clears
* all fields except the device handle.
* <p>
* When a device is destroyed, resources that were acquired on behalf of the
* programmer need to be returned to the operating system. For example, if
* the device allocated a font to be used as the system font, this font
* would be freed in <code>release</code>. Also,to assist the garbage
* collector and minimize the amount of memory that is not reclaimed when
* the programmer keeps a reference to a disposed device, all fields except
* the handle are zero'd. The handle is needed by <code>destroy</code>.
* </p>
* This method is called before <code>destroy</code>. </p>
* <p>
* If subclasses reimplement this method, they must call the
* <code>super</code> implementation.
* </p>
*
* @see #dispose
* @see #destroy
*/
protected void release() {
// TODO
}
/**
* If the underlying window system supports printing warning messages to the
* console, setting warnings to <code>false</code> prevents these messages
* from being printed. If the argument is <code>true</code> then message
* printing is not blocked.
*
* @param warnings
* <code>true</code>if warnings should be printed, and
* <code>false</code> otherwise
*
* @exception SWTException
* <ul>
* <li>ERROR_DEVICE_DISPOSED - if the receiver has been
* disposed</li>
* </ul>
*/
public void setWarnings(boolean warnings) {
checkDevice();
// TODO
}
}