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comparison org.eclipse.swt.win32.win32.x86/src/org/eclipse/swt/custom/ScrolledComposite.d @ 0:6dd524f61e62

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add dwt win and basic java stuff
author Frank Benoit <benoit@tionex.de>
date Mon, 02 Mar 2009 14:44:16 +0100
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1 /*******************************************************************************
2 * Copyright (c) 2000, 2008 IBM Corporation and others.
3 * All rights reserved. This program and the accompanying materials
4 * are made available under the terms of the Eclipse Public License v1.0
5 * which accompanies this distribution, and is available at
6 * http://www.eclipse.org/legal/epl-v10.html
7 *
8 * Contributors:
9 * IBM Corporation - initial API and implementation
10 * Port to the D programming language:
11 * Frank Benoit <benoit@tionex.de>
12 *******************************************************************************/
13 module org.eclipse.swt.custom.ScrolledComposite;
14
15 import java.lang.all;
16
17
18 import org.eclipse.swt.SWT;
19 import org.eclipse.swt.SWTException;
20 import org.eclipse.swt.events.DisposeEvent;
21 import org.eclipse.swt.events.DisposeListener;
22 import org.eclipse.swt.graphics.Point;
23 import org.eclipse.swt.graphics.Rectangle;
24 import org.eclipse.swt.widgets.Composite;
25 import org.eclipse.swt.widgets.Control;
26 import org.eclipse.swt.widgets.Display;
27 import org.eclipse.swt.widgets.Event;
28 import org.eclipse.swt.widgets.Layout;
29 import org.eclipse.swt.widgets.Listener;
30 import org.eclipse.swt.widgets.ScrollBar;
31 import org.eclipse.swt.widgets.Shell;
32 import org.eclipse.swt.custom.ScrolledCompositeLayout;
33
34 /**
35 * A ScrolledComposite provides scrollbars and will scroll its content when the user
36 * uses the scrollbars.
37 *
38 *
39 * <p>There are two ways to use the ScrolledComposite:
40 *
41 * <p>
42 * 1) Set the size of the control that is being scrolled and the ScrolledComposite
43 * will show scrollbars when the contained control can not be fully seen.
44 *
45 * 2) The second way imitates the way a browser would work. Set the minimum size of
46 * the control and the ScrolledComposite will show scroll bars if the visible area is
47 * less than the minimum size of the control and it will expand the size of the control
48 * if the visible area is greater than the minimum size. This requires invoking
49 * both setMinWidth(), setMinHeight() and setExpandHorizontal(), setExpandVertical().
50 *
51 * <code><pre>
52 * public static void main (String [] args) {
53 * Display display = new Display ();
54 * Color red = display.getSystemColor(SWT.COLOR_RED);
55 * Color blue = display.getSystemColor(SWT.COLOR_BLUE);
56 * Shell shell = new Shell (display);
57 * shell.setLayout(new FillLayout());
58 *
59 * // set the size of the scrolled content - method 1
60 * final ScrolledComposite sc1 = new ScrolledComposite(shell, SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER);
61 * final Composite c1 = new Composite(sc1, SWT.NONE);
62 * sc1.setContent(c1);
63 * c1.setBackground(red);
64 * GridLayout layout = new GridLayout();
65 * layout.numColumns = 4;
66 * c1.setLayout(layout);
67 * Button b1 = new Button (c1, SWT.PUSH);
68 * b1.setText("first button");
69 * c1.setSize(c1.computeSize(SWT.DEFAULT, SWT.DEFAULT));
70 *
71 * // set the minimum width and height of the scrolled content - method 2
72 * final ScrolledComposite sc2 = new ScrolledComposite(shell, SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER);
73 * sc2.setExpandHorizontal(true);
74 * sc2.setExpandVertical(true);
75 * final Composite c2 = new Composite(sc2, SWT.NONE);
76 * sc2.setContent(c2);
77 * c2.setBackground(blue);
78 * layout = new GridLayout();
79 * layout.numColumns = 4;
80 * c2.setLayout(layout);
81 * Button b2 = new Button (c2, SWT.PUSH);
82 * b2.setText("first button");
83 * sc2.setMinSize(c2.computeSize(SWT.DEFAULT, SWT.DEFAULT));
84 *
85 * Button add = new Button (shell, SWT.PUSH);
86 * add.setText("add children");
87 * final int[] index = new int[]{0};
88 * add.addListener(SWT.Selection, new Listener() {
89 * public void handleEvent(Event e) {
90 * index[0]++;
91 * Button button = new Button(c1, SWT.PUSH);
92 * button.setText("button "+index[0]);
93 * // reset size of content so children can be seen - method 1
94 * c1.setSize(c1.computeSize(SWT.DEFAULT, SWT.DEFAULT));
95 * c1.layout();
96 *
97 * button = new Button(c2, SWT.PUSH);
98 * button.setText("button "+index[0]);
99 * // reset the minimum width and height so children can be seen - method 2
100 * sc2.setMinSize(c2.computeSize(SWT.DEFAULT, SWT.DEFAULT));
101 * c2.layout();
102 * }
103 * });
104 *
105 * shell.open ();
106 * while (!shell.isDisposed ()) {
107 * if (!display.readAndDispatch ()) display.sleep ();
108 * }
109 * display.dispose ();
110 * }
111 * </pre></code>
112 *
113 * <dl>
114 * <dt><b>Styles:</b><dd>H_SCROLL, V_SCROLL
115 * </dl>
116 *
117 * @see <a href="http://www.eclipse.org/swt/snippets/#scrolledcomposite">ScrolledComposite snippets</a>
118 * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
119 */
120 public class ScrolledComposite : Composite {
121
122 Control content;
123 Listener contentListener;
124 Listener filter;
125
126 int minHeight = 0;
127 int minWidth = 0;
128 bool expandHorizontal = false;
129 bool expandVertical = false;
130 bool alwaysShowScroll = false;
131 bool showFocusedControl = false;
132
133 /**
134 * Constructs a new instance of this class given its parent
135 * and a style value describing its behavior and appearance.
136 * <p>
137 * The style value is either one of the style constants defined in
138 * class <code>SWT</code> which is applicable to instances of this
139 * class, or must be built by <em>bitwise OR</em>'ing together
140 * (that is, using the <code>int</code> "|" operator) two or more
141 * of those <code>SWT</code> style constants. The class description
142 * lists the style constants that are applicable to the class.
143 * Style bits are also inherited from superclasses.
144 * </p>
145 *
146 * @param parent a widget which will be the parent of the new instance (cannot be null)
147 * @param style the style of widget to construct
148 *
149 * @exception IllegalArgumentException <ul>
150 * <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
151 * </ul>
152 * @exception SWTException <ul>
153 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
154 * </ul>
155 *
156 * @see SWT#H_SCROLL
157 * @see SWT#V_SCROLL
158 * @see #getStyle()
159 */
160 public this(Composite parent, int style) {
161 super(parent, checkStyle(style));
162 super.setLayout(new ScrolledCompositeLayout());
163 ScrollBar hBar = getHorizontalBar ();
164 if (hBar !is null) {
165 hBar.setVisible(false);
166 hBar.addListener (SWT.Selection, new class() Listener {
167 public void handleEvent (Event e) {
168 hScroll();
169 }
170 });
171 }
172
173 ScrollBar vBar = getVerticalBar ();
174 if (vBar !is null) {
175 vBar.setVisible(false);
176 vBar.addListener (SWT.Selection, new class() Listener {
177 public void handleEvent (Event e) {
178 vScroll();
179 }
180 });
181 }
182
183 contentListener = new class() Listener {
184 public void handleEvent(Event e) {
185 if (e.type !is SWT.Resize) return;
186 layout(false);
187 }
188 };
189
190 filter = new class() Listener {
191 public void handleEvent(Event event) {
192 if (auto control = cast(Control)event.widget ) {
193 if (contains(control)) showControl(control);
194 }
195 }
196 };
197
198 addDisposeListener(new class() DisposeListener {
199 public void widgetDisposed(DisposeEvent e) {
200 getDisplay().removeFilter(SWT.FocusIn, filter);
201 }
202 });
203 }
204
205 static int checkStyle (int style) {
206 int mask = SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER | SWT.LEFT_TO_RIGHT | SWT.RIGHT_TO_LEFT;
207 return style & mask;
208 }
209
210 bool contains(Control control) {
211 if (control is null || control.isDisposed()) return false;
212
213 Composite parent = control.getParent();
214 while (parent !is null && !( null !is cast(Shell)parent )) {
215 if (this is parent) return true;
216 parent = parent.getParent();
217 }
218 return false;
219 }
220
221 /**
222 * Returns the Always Show Scrollbars flag. True if the scrollbars are
223 * always shown even if they are not required. False if the scrollbars are only
224 * visible when some part of the composite needs to be scrolled to be seen.
225 * The H_SCROLL and V_SCROLL style bits are also required to enable scrollbars in the
226 * horizontal and vertical directions.
227 *
228 * @return the Always Show Scrollbars flag value
229 */
230 public bool getAlwaysShowScrollBars() {
231 //checkWidget();
232 return alwaysShowScroll;
233 }
234
235 /**
236 * Returns <code>true</code> if the content control
237 * will be expanded to fill available horizontal space.
238 *
239 * @return the receiver's horizontal expansion state
240 *
241 * @exception SWTException <ul>
242 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
243 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
244 * </ul>
245 *
246 * @since 3.2
247 */
248 public bool getExpandHorizontal() {
249 checkWidget();
250 return expandHorizontal;
251 }
252
253 /**
254 * Returns <code>true</code> if the content control
255 * will be expanded to fill available vertical space.
256 *
257 * @return the receiver's vertical expansion state
258 *
259 * @exception SWTException <ul>
260 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
261 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
262 * </ul>
263 *
264 * @since 3.2
265 */
266 public bool getExpandVertical() {
267 checkWidget();
268 return expandVertical;
269 }
270
271 /**
272 * Returns the minimum width of the content control.
273 *
274 * @return the minimum width
275 *
276 * @exception SWTException <ul>
277 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
278 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
279 * </ul>
280 *
281 * @since 3.2
282 */
283 public int getMinWidth() {
284 checkWidget();
285 return minWidth;
286 }
287
288 /**
289 * Returns the minimum height of the content control.
290 *
291 * @return the minimum height
292 *
293 * @exception SWTException <ul>
294 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
295 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
296 * </ul>
297 *
298 * @since 3.2
299 */
300 public int getMinHeight() {
301 checkWidget();
302 return minHeight;
303 }
304
305 /**
306 * Get the content that is being scrolled.
307 *
308 * @return the control displayed in the content area
309 */
310 public Control getContent() {
311 //checkWidget();
312 return content;
313 }
314
315 /**
316 * Returns <code>true</code> if the receiver automatically scrolls to a focused child control
317 * to make it visible. Otherwise, returns <code>false</code>.
318 *
319 * @return a bool indicating whether focused child controls are automatically scrolled into the viewport
320 *
321 * @exception SWTException <ul>
322 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
323 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
324 * </ul>
325 *
326 * @since 3.4
327 */
328 public bool getShowFocusedControl() {
329 checkWidget();
330 return showFocusedControl;
331 }
332
333 void hScroll() {
334 if (content is null) return;
335 Point location = content.getLocation ();
336 ScrollBar hBar = getHorizontalBar ();
337 int hSelection = hBar.getSelection ();
338 content.setLocation (-hSelection, location.y);
339 }
340 bool needHScroll(Rectangle contentRect, bool vVisible) {
341 ScrollBar hBar = getHorizontalBar();
342 if (hBar is null) return false;
343
344 Rectangle hostRect = getBounds();
345 int border = getBorderWidth();
346 hostRect.width -= 2*border;
347 ScrollBar vBar = getVerticalBar();
348 if (vVisible && vBar !is null) hostRect.width -= vBar.getSize().x;
349
350 if (!expandHorizontal && contentRect.width > hostRect.width) return true;
351 if (expandHorizontal && minWidth > hostRect.width) return true;
352 return false;
353 }
354
355 bool needVScroll(Rectangle contentRect, bool hVisible) {
356 ScrollBar vBar = getVerticalBar();
357 if (vBar is null) return false;
358
359 Rectangle hostRect = getBounds();
360 int border = getBorderWidth();
361 hostRect.height -= 2*border;
362 ScrollBar hBar = getHorizontalBar();
363 if (hVisible && hBar !is null) hostRect.height -= hBar.getSize().y;
364
365 if (!expandVertical && contentRect.height > hostRect.height) return true;
366 if (expandVertical && minHeight > hostRect.height) return true;
367 return false;
368 }
369
370 /**
371 * Return the point in the content that currently appears in the top left
372 * corner of the scrolled composite.
373 *
374 * @return the point in the content that currently appears in the top left
375 * corner of the scrolled composite. If no content has been set, this returns
376 * (0, 0).
377 *
378 * @exception SWTException <ul>
379 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
380 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
381 * </ul>
382 *
383 * @since 2.0
384 */
385 public Point getOrigin() {
386 checkWidget();
387 if (content is null) return new Point(0, 0);
388 Point location = content.getLocation();
389 return new Point(-location.x, -location.y);
390 }
391 /**
392 * Scrolls the content so that the specified point in the content is in the top
393 * left corner. If no content has been set, nothing will occur.
394 *
395 * Negative values will be ignored. Values greater than the maximum scroll
396 * distance will result in scrolling to the end of the scrollbar.
397 *
398 * @param origin the point on the content to appear in the top left corner
399 *
400 * @exception SWTException <ul>
401 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
402 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
403 * <li>ERROR_INVALID_ARGUMENT - value of origin is outside of content
404 * </ul>
405 * @since 2.0
406 */
407 public void setOrigin(Point origin) {
408 setOrigin(origin.x, origin.y);
409 }
410 /**
411 * Scrolls the content so that the specified point in the content is in the top
412 * left corner. If no content has been set, nothing will occur.
413 *
414 * Negative values will be ignored. Values greater than the maximum scroll
415 * distance will result in scrolling to the end of the scrollbar.
416 *
417 * @param x the x coordinate of the content to appear in the top left corner
418 *
419 * @param y the y coordinate of the content to appear in the top left corner
420 *
421 * @exception SWTException <ul>
422 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
423 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
424 * </ul>
425 *
426 * @since 2.0
427 */
428 public void setOrigin(int x, int y) {
429 checkWidget();
430 if (content is null) return;
431 ScrollBar hBar = getHorizontalBar ();
432 if (hBar !is null) {
433 hBar.setSelection(x);
434 x = -hBar.getSelection ();
435 } else {
436 x = 0;
437 }
438 ScrollBar vBar = getVerticalBar ();
439 if (vBar !is null) {
440 vBar.setSelection(y);
441 y = -vBar.getSelection ();
442 } else {
443 y = 0;
444 }
445 content.setLocation(x, y);
446 }
447 /**
448 * Set the Always Show Scrollbars flag. True if the scrollbars are
449 * always shown even if they are not required. False if the scrollbars are only
450 * visible when some part of the composite needs to be scrolled to be seen.
451 * The H_SCROLL and V_SCROLL style bits are also required to enable scrollbars in the
452 * horizontal and vertical directions.
453 *
454 * @param show true to show the scrollbars even when not required, false to show scrollbars only when required
455 *
456 * @exception SWTException <ul>
457 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
458 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
459 * </ul>
460 */
461 public void setAlwaysShowScrollBars(bool show) {
462 checkWidget();
463 if (show is alwaysShowScroll) return;
464 alwaysShowScroll = show;
465 ScrollBar hBar = getHorizontalBar ();
466 if (hBar !is null && alwaysShowScroll) hBar.setVisible(true);
467 ScrollBar vBar = getVerticalBar ();
468 if (vBar !is null && alwaysShowScroll) vBar.setVisible(true);
469 layout(false);
470 }
471
472 /**
473 * Set the content that will be scrolled.
474 *
475 * @param content the control to be displayed in the content area
476 *
477 * @exception SWTException <ul>
478 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
479 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
480 * </ul>
481 */
482 public void setContent(Control content) {
483 checkWidget();
484 if (this.content !is null && !this.content.isDisposed()) {
485 this.content.removeListener(SWT.Resize, contentListener);
486 this.content.setBounds(new Rectangle(-200, -200, 0, 0));
487 }
488
489 this.content = content;
490 ScrollBar vBar = getVerticalBar ();
491 ScrollBar hBar = getHorizontalBar ();
492 if (this.content !is null) {
493 if (vBar !is null) {
494 vBar.setMaximum (0);
495 vBar.setThumb (0);
496 vBar.setSelection(0);
497 }
498 if (hBar !is null) {
499 hBar.setMaximum (0);
500 hBar.setThumb (0);
501 hBar.setSelection(0);
502 }
503 content.setLocation(0, 0);
504 layout(false);
505 this.content.addListener(SWT.Resize, contentListener);
506 } else {
507 if (hBar !is null) hBar.setVisible(alwaysShowScroll);
508 if (vBar !is null) vBar.setVisible(alwaysShowScroll);
509 }
510 }
511 /**
512 * Configure the ScrolledComposite to resize the content object to be as wide as the
513 * ScrolledComposite when the width of the ScrolledComposite is greater than the
514 * minimum width specified in setMinWidth. If the ScrolledComposite is less than the
515 * minimum width, the content will not be resized and instead the horizontal scroll bar will be
516 * used to view the entire width.
517 * If expand is false, this behaviour is turned off. By default, this behaviour is turned off.
518 *
519 * @param expand true to expand the content control to fill available horizontal space
520 *
521 * @exception SWTException <ul>
522 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
523 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
524 * </ul>
525 */
526 public void setExpandHorizontal(bool expand) {
527 checkWidget();
528 if (expand is expandHorizontal) return;
529 expandHorizontal = expand;
530 layout(false);
531 }
532 /**
533 * Configure the ScrolledComposite to resize the content object to be as tall as the
534 * ScrolledComposite when the height of the ScrolledComposite is greater than the
535 * minimum height specified in setMinHeight. If the ScrolledComposite is less than the
536 * minimum height, the content will not be resized and instead the vertical scroll bar will be
537 * used to view the entire height.
538 * If expand is false, this behaviour is turned off. By default, this behaviour is turned off.
539 *
540 * @param expand true to expand the content control to fill available vertical space
541 *
542 * @exception SWTException <ul>
543 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
544 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
545 * </ul>
546 */
547 public void setExpandVertical(bool expand) {
548 checkWidget();
549 if (expand is expandVertical) return;
550 expandVertical = expand;
551 layout(false);
552 }
553 /**
554 * Sets the layout which is associated with the receiver to be
555 * the argument which may be null.
556 * <p>
557 * Note: No Layout can be set on this Control because it already
558 * manages the size and position of its children.
559 * </p>
560 *
561 * @param layout the receiver's new layout or null
562 *
563 * @exception SWTException <ul>
564 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
565 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
566 * </ul>
567 */
568 public override void setLayout (Layout layout) {
569 checkWidget();
570 return;
571 }
572 /**
573 * Specify the minimum height at which the ScrolledComposite will begin scrolling the
574 * content with the vertical scroll bar. This value is only relevant if
575 * setExpandVertical(true) has been set.
576 *
577 * @param height the minimum height or 0 for default height
578 *
579 * @exception SWTException <ul>
580 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
581 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
582 * </ul>
583 */
584 public void setMinHeight(int height) {
585 setMinSize(minWidth, height);
586 }
587 /**
588 * Specify the minimum width and height at which the ScrolledComposite will begin scrolling the
589 * content with the horizontal scroll bar. This value is only relevant if
590 * setExpandHorizontal(true) and setExpandVertical(true) have been set.
591 *
592 * @param size the minimum size or null for the default size
593 *
594 * @exception SWTException <ul>
595 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
596 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
597 * </ul>
598 */
599 public void setMinSize(Point size) {
600 if (size is null) {
601 setMinSize(0, 0);
602 } else {
603 setMinSize(size.x, size.y);
604 }
605 }
606 /**
607 * Specify the minimum width and height at which the ScrolledComposite will begin scrolling the
608 * content with the horizontal scroll bar. This value is only relevant if
609 * setExpandHorizontal(true) and setExpandVertical(true) have been set.
610 *
611 * @param width the minimum width or 0 for default width
612 * @param height the minimum height or 0 for default height
613 *
614 * @exception SWTException <ul>
615 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
616 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
617 * </ul>
618 */
619 public void setMinSize(int width, int height) {
620 checkWidget();
621 if (width is minWidth && height is minHeight) return;
622 minWidth = Math.max(0, width);
623 minHeight = Math.max(0, height);
624 layout(false);
625 }
626 /**
627 * Specify the minimum width at which the ScrolledComposite will begin scrolling the
628 * content with the horizontal scroll bar. This value is only relevant if
629 * setExpandHorizontal(true) has been set.
630 *
631 * @param width the minimum width or 0 for default width
632 *
633 * @exception SWTException <ul>
634 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
635 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
636 * </ul>
637 */
638 public void setMinWidth(int width) {
639 setMinSize(width, minHeight);
640 }
641
642 /**
643 * Configure the receiver to automatically scroll to a focused child control
644 * to make it visible.
645 *
646 * If show is <code>false</code>, show a focused control is off.
647 * By default, show a focused control is off.
648 *
649 * @param show <code>true</code> to show a focused control.
650 *
651 * @exception SWTException <ul>
652 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
653 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
654 * </ul>
655 *
656 * @since 3.4
657 */
658 public void setShowFocusedControl(bool show) {
659 checkWidget();
660 if (showFocusedControl is show) return;
661 Display display = getDisplay();
662 display.removeFilter(SWT.FocusIn, filter);
663 showFocusedControl = show;
664 if (!showFocusedControl) return;
665 display.addFilter(SWT.FocusIn, filter);
666 Control control = display.getFocusControl();
667 if (contains(control)) showControl(control);
668 }
669
670 /**
671 * Scrolls the content of the receiver so that the control is visible.
672 *
673 * @param control the control to be shown
674 *
675 * @exception IllegalArgumentException <ul>
676 * <li>ERROR_NULL_ARGUMENT - if the control is null</li>
677 * <li>ERROR_INVALID_ARGUMENT - if the control has been disposed</li>
678 * </ul>
679 * @exception SWTException <ul>
680 * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
681 * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
682 * </ul>
683 *
684 * @since 3.4
685 */
686 public void showControl(Control control) {
687 checkWidget ();
688 if (control is null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
689 if (control.isDisposed ()) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
690 if (!contains(control)) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
691
692 Rectangle itemRect = getDisplay().map(control.getParent(), this, control.getBounds());
693 Rectangle area = getClientArea();
694 Point origin = getOrigin();
695 if (itemRect.x < 0) origin.x = Math.max(0, origin.x + itemRect.x);
696 if (itemRect.y < 0) origin.y = Math.max(0, origin.y + itemRect.y);
697 if (area.width < itemRect.x + itemRect.width) origin.x = Math.max(0, origin.x + itemRect.x + itemRect.width - area.width);
698 if (area.height < itemRect.y + itemRect.height) origin.y = Math.max(0, origin.y + itemRect.y + itemRect.height - area.height);
699 setOrigin(origin);
700 }
701
702 void vScroll() {
703 if (content is null) return;
704 Point location = content.getLocation ();
705 ScrollBar vBar = getVerticalBar ();
706 int vSelection = vBar.getSelection ();
707 content.setLocation (location.x, -vSelection);
708 }
709 }