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1
11 package org.eclipse.swt.custom;
12
13 import org.eclipse.swt.*;
14 import org.eclipse.swt.graphics.*;
15 import org.eclipse.swt.widgets.*;
16
17
22 class ScrolledCompositeLayout extends Layout {
23
24 boolean inLayout = false;
25 static final int DEFAULT_WIDTH = 64;
26 static final int DEFAULT_HEIGHT = 64;
27
28 protected Point computeSize(Composite composite, int wHint, int hHint, boolean flushCache) {
29 ScrolledComposite sc = (ScrolledComposite)composite;
30 Point size = new Point(DEFAULT_WIDTH, DEFAULT_HEIGHT);
31 if (sc.content != null) {
32 Point preferredSize = sc.content.computeSize(wHint, hHint, flushCache);
33 Point currentSize = sc.content.getSize();
34 size.x = sc.getExpandHorizontal() ? preferredSize.x : currentSize.x;
35 size.y = sc.getExpandVertical() ? preferredSize.y : currentSize.y;
36 }
37 size.x = Math.max(size.x, sc.minWidth);
38 size.y = Math.max(size.y, sc.minHeight);
39 if (wHint != SWT.DEFAULT) size.x = wHint;
40 if (hHint != SWT.DEFAULT) size.y = hHint;
41 return size;
42 }
43
44 protected boolean flushCache(Control control) {
45 return true;
46 }
47
48 protected void layout(Composite composite, boolean flushCache) {
49 if (inLayout) return;
50 ScrolledComposite sc = (ScrolledComposite)composite;
51 if (sc.content == null) return;
52 ScrollBar hBar = sc.getHorizontalBar();
53 ScrollBar vBar = sc.getVerticalBar();
54 if (hBar != null) {
55 if (hBar.getSize().y >= sc.getSize().y) {
56 return;
57 }
58 }
59 if (vBar != null) {
60 if (vBar.getSize().x >= sc.getSize().x) {
61 return;
62 }
63 }
64 inLayout = true;
65 Rectangle contentRect = sc.content.getBounds();
66 if (!sc.alwaysShowScroll) {
67 boolean hVisible = sc.needHScroll(contentRect, false);
68 boolean vVisible = sc.needVScroll(contentRect, hVisible);
69 if (!hVisible && vVisible) hVisible = sc.needHScroll(contentRect, vVisible);
70 if (hBar != null) hBar.setVisible(hVisible);
71 if (vBar != null) vBar.setVisible(vVisible);
72 }
73 Rectangle hostRect = sc.getClientArea();
74 if (sc.expandHorizontal) {
75 contentRect.width = Math.max(sc.minWidth, hostRect.width);
76 }
77 if (sc.expandVertical) {
78 contentRect.height = Math.max(sc.minHeight, hostRect.height);
79 }
80
81 if (hBar != null) {
82 hBar.setMaximum (contentRect.width);
83 hBar.setThumb (Math.min (contentRect.width, hostRect.width));
84 int hPage = contentRect.width - hostRect.width;
85 int hSelection = hBar.getSelection ();
86 if (hSelection >= hPage) {
87 if (hPage <= 0) {
88 hSelection = 0;
89 hBar.setSelection(0);
90 }
91 contentRect.x = -hSelection;
92 }
93 }
94
95 if (vBar != null) {
96 vBar.setMaximum (contentRect.height);
97 vBar.setThumb (Math.min (contentRect.height, hostRect.height));
98 int vPage = contentRect.height - hostRect.height;
99 int vSelection = vBar.getSelection ();
100 if (vSelection >= vPage) {
101 if (vPage <= 0) {
102 vSelection = 0;
103 vBar.setSelection(0);
104 }
105 contentRect.y = -vSelection;
106 }
107 }
108
109 sc.content.setBounds (contentRect);
110 inLayout = false;
111 }
112 }
113 |
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