/******************************************************************************* * Copyright (c) 2000, 2012 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.widgets; import org.eclipse.swt.*; import org.eclipse.swt.internal.cairo.*; import org.eclipse.swt.internal.gtk.*; import org.eclipse.swt.graphics.*; /** * Instances of this class are controls which are capable * of containing other controls. *
* Note: The NO_BACKGROUND
, NO_FOCUS
, NO_MERGE_PAINTS
,
* and NO_REDRAW_RESIZE
styles are intended for use with Canvas
.
* They can be used with Composite
if you are drawing your own, but their
* behavior is undefined if they are used with subclasses of Composite
other
* than Canvas
.
*
* Note: The CENTER
style, although undefined for composites, has the
* same value as EMBEDDED
which is used to embed widgets from other
* widget toolkits into SWT. On some operating systems (GTK, Motif), this may cause
* the children of this composite to be obscured.
*
* This class may be subclassed by custom control implementors * who are building controls that are constructed from aggregates * of other controls. *
* * @see Canvas * @see Composite snippets * @see Sample code and further information */ public class Composite extends Scrollable { /** * the handle to the OS resource * (Warning: This field is platform dependent) ** IMPORTANT: This field is not part of the SWT * public API. 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 accessed from application code. *
* * @noreference This field is not intended to be referenced by clients. */ public long /*int*/ embeddedHandle; long /*int*/ imHandle, socketHandle; Layout layout; Control[] tabList; int layoutCount, backgroundMode; static final String NO_INPUT_METHOD = "org.eclipse.swt.internal.gtk.noInputMethod"; //$NON-NLS-1$ Composite () { /* Do nothing */ } /** * Constructs a new instance of this class given its parent * and a style value describing its behavior and appearance. *
* The style value is either one of the style constants defined in
* class SWT
which is applicable to instances of this
* class, or must be built by bitwise OR'ing together
* (that is, using the int
"|" operator) two or more
* of those SWT
style constants. The class description
* lists the style constants that are applicable to the class.
* Style bits are also inherited from superclasses.
*
offsetX
and offsetY
are used to map from
* the gc
origin to the origin of the parent image background. This is useful
* to ensure proper alignment of the image background.
*
* @param gc the gc where the rectangle is to be filled
* @param x the x coordinate of the rectangle to be filled
* @param y the y coordinate of the rectangle to be filled
* @param width the width of the rectangle to be filled
* @param height the height of the rectangle to be filled
* @param offsetX the image background x offset
* @param offsetY the image background y offset
*
* @exception IllegalArgumentException INHERIT_NONE
, INHERIT_DEFAULT
,
* INHERIT_FORCE
.
*
* @return the background mode
*
* @exception SWTException * Note: This is not the actual structure used by the receiver * to maintain its list of children, so modifying the array will * not affect the receiver. *
* * @return an array of children * * @see Control#moveAbove * @see Control#moveBelow * * @exception SWTExceptiontrue
if the receiver has deferred
* the performing of layout, and false
otherwise.
*
* @return the receiver's deferred layout state
*
* @exception SWTException false
* is returned.
*
* @return the receiver's deferred layout state
*
* @exception SWTException
* This is equivalent to calling layout(true)
.
*
* Note: Layout is different from painting. If a child is * moved or resized such that an area in the parent is * exposed, then the parent will paint. If no child is * affected, the parent will not paint. *
* * @exception SWTExceptiontrue
the layout must not rely
* on any information it has cached about the immediate children. If it
* is false
the layout may (potentially) optimize the
* work it is doing by assuming that none of the receiver's
* children has changed state since the last layout.
* If the receiver does not have a layout, do nothing.
*
* If a child is resized as a result of a call to layout, the
* resize event will invoke the layout of the child. The layout
* will cascade down through all child widgets in the receiver's widget
* tree until a child is encountered that does not resize. Note that
* a layout due to a resize will not flush any cached information
* (same as layout(false)
).
*
* Note: Layout is different from painting. If a child is * moved or resized such that an area in the parent is * exposed, then the parent will paint. If no child is * affected, the parent will not paint. *
* * @param changedtrue
if the layout must flush its caches, and false
otherwise
*
* @exception SWTException true
the layout must not rely
* on any information it has cached about its children. If it
* is false
the layout may (potentially) optimize the
* work it is doing by assuming that none of the receiver's
* children has changed state since the last layout.
* If the all argument is true
the layout will cascade down
* through all child widgets in the receiver's widget tree, regardless of
* whether the child has changed size. The changed argument is applied to
* all layouts. If the all argument is false
, the layout will
* not cascade down through all child widgets in the receiver's widget
* tree. However, if a child is resized as a result of a call to layout, the
* resize event will invoke the layout of the child. Note that
* a layout due to a resize will not flush any cached information
* (same as layout(false)
).
*
* * Note: Layout is different from painting. If a child is * moved or resized such that an area in the parent is * exposed, then the parent will paint. If no child is * affected, the parent will not paint. *
* * @param changedtrue
if the layout must flush its caches, and false
otherwise
* @param all true
if all children in the receiver's widget tree should be laid out, and false
otherwise
*
* @exception SWTException * Note: Layout is different from painting. If a child is * moved or resized such that an area in the parent is * exposed, then the parent will paint. If no child is * affected, the parent will not paint. *
* * @param changed a control that has had a state change which requires a recalculation of its size * * @exception IllegalArgumentException
* The parameter flags
may be a combination of:
*
* When the changed
array is specified, the flags SWT.ALL
* and SWT.CHANGED
have no effect. In this case, the layouts in the
* hierarchy must not rely on any information cached about the changed control or
* any of its ancestors. The layout may (potentially) optimize the
* work it is doing by assuming that none of the peers of the changed
* control have changed state since the last layout.
* If an ancestor does not have a layout, skip it.
*
* When the changed
array is not specified, the flag SWT.ALL
* indicates that the whole widget tree should be laid out. And the flag
* SWT.CHANGED
indicates that the layouts should flush any cached
* information for all controls that are laid out.
*
* The SWT.DEFER
flag always causes the layout to be deferred by
* calling Composite.setLayoutDeferred(true)
and scheduling a call
* to Composite.setLayoutDeferred(false)
, which will happen when
* appropriate (usually before the next event is handled). When this flag is set,
* the application should not call Composite.setLayoutDeferred(boolean)
.
*
* Note: Layout is different from painting. If a child is * moved or resized such that an area in the parent is * exposed, then the parent will paint. If no child is * affected, the parent will not paint. *
* * @param changed a control that has had a state change which requires a recalculation of its size * @param flags the flags specifying how the layout should happen * * @exception IllegalArgumentExceptionINHERIT_NONE
, INHERIT_DEFAULT
,
* INHERIT_FORCE
.
*
* @param mode the new background mode
*
* @exception SWTException true
, causes subsequent layout
* operations in the receiver or any of its children to be ignored.
* No layout of any kind can occur in the receiver or any of its
* children until the flag is set to false.
* Layout operations that occurred while the flag was
* true
are remembered and when the flag is set to
* false
, the layout operations are performed in an
* optimized manner. Nested calls to this method are stacked.
*
* @param defer the new defer state
*
* @exception SWTException