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1
11 package org.eclipse.swt.dnd;
12
13
14 import org.eclipse.swt.custom.*;
15 import org.eclipse.swt.graphics.*;
16 import org.eclipse.swt.internal.win32.*;
17
18 class StyledTextDragAndDropEffect extends DragAndDropEffect {
19 StyledText text;
20 long scrollBeginTime;
21 int scrollX = -1, scrollY = -1;
22
23 static final int SCROLL_HYSTERESIS = 100; static final int SCROLL_TOLERANCE = 20;
26 StyledTextDragAndDropEffect(StyledText control) {
27 text = control;
28 }
29 void showDropTargetEffect(int effect, int x, int y) {
30 Point pt = text.getDisplay().map(null, text, x, y);
31 if ((effect & DND.FEEDBACK_SCROLL) == 0) {
32 scrollBeginTime = 0;
33 scrollX = scrollY = -1;
34 } else {
35 if (text.getCharCount() == 0) {
36 scrollBeginTime = 0;
37 scrollX = scrollY = -1;
38 } else {
39 if (scrollX != -1 && scrollY != -1 && scrollBeginTime != 0 &&
40 (pt.x >= scrollX && pt.x <= (scrollX + SCROLL_TOLERANCE) ||
41 pt.y >= scrollY && pt.y <= (scrollY + SCROLL_TOLERANCE))) {
42 if (System.currentTimeMillis() >= scrollBeginTime) {
43 Rectangle area = text.getClientArea();
44 Rectangle bounds = text.getTextBounds(0, 0);
45 int charWidth = bounds.width;
46 if (pt.x < area.x + 2*charWidth) {
47 int leftPixel = text.getHorizontalPixel();
48 text.setHorizontalPixel(leftPixel - charWidth);
49 if (text.getHorizontalPixel() != leftPixel) {
50 text.redraw();
51 }
52 }
53 if (pt.x > area.width - 2*charWidth) {
54 int leftPixel = text.getHorizontalPixel();
55 text.setHorizontalPixel(leftPixel + charWidth);
56 if (text.getHorizontalPixel() != leftPixel) {
57 text.redraw();
58 }
59 }
60 int lineHeight = bounds.height;
61 if (pt.y < area.y + lineHeight) {
62 int topPixel = text.getTopPixel();
63 text.setTopPixel(topPixel - lineHeight);
64 if (text.getTopPixel() != topPixel) {
65 text.redraw();
66 }
67 }
68 if (pt.y > area.height - lineHeight) {
69 int topPixel = text.getTopPixel();
70 text.setTopPixel(topPixel + lineHeight);
71 if (text.getTopPixel() != topPixel) {
72 text.redraw();
73 }
74 }
75 scrollBeginTime = 0;
76 scrollX = scrollY = -1;
77 }
78 } else {
79 scrollBeginTime = System.currentTimeMillis() + SCROLL_HYSTERESIS;
80 scrollX = pt.x;
81 scrollY = pt.y;
82 }
83 }
84 }
85
86 if ((effect & DND.FEEDBACK_SELECT) != 0) {
87 StyledTextContent content = text.getContent();
88 int oldOffset = text.getCaretOffset();
89 int newOffset = -1;
90 try {
91 newOffset = text.getOffsetAtLocation(pt);
92 } catch (IllegalArgumentException  ex1) {
93 int maxOffset = content.getCharCount();
94 Point maxLocation = text.getLocationAtOffset(maxOffset);
95 if (pt.y >= maxLocation.y) {
96 try {
97 newOffset = text.getOffsetAtLocation(new Point(pt.x, maxLocation.y));
98 } catch (IllegalArgumentException ex2) {
99 newOffset = maxOffset;
100 }
101 } else {
102 try {
103 int startOffset = text.getOffsetAtLocation(new Point(0, pt.y));
104 int endOffset = maxOffset;
105 int line = content.getLineAtOffset(startOffset);
106 int lineCount = content.getLineCount();
107 if (line + 1 < lineCount) {
108 endOffset = content.getOffsetAtLine(line + 1) - 1;
109 }
110 int lineHeight = text.getLineHeight(startOffset);
111 for (int i = endOffset; i >= startOffset; i--) {
112 Point p = text.getLocationAtOffset(i);
113 if (p.x < pt.x && p.y < pt.y && p.y + lineHeight > pt.y) {
114 newOffset = i;
115 break;
116 }
117 }
118 } catch (IllegalArgumentException ex2) {
119 newOffset = -1;
120 }
121 }
122 }
123 if (newOffset != -1 && newOffset != oldOffset) {
124 int line = content.getLineAtOffset(newOffset);
127 int lineOffset = content.getOffsetAtLine(line);
128 int offsetInLine = newOffset - lineOffset;
129 if (offsetInLine > content.getLine(line).length()) {
133 newOffset = Math.max(0, newOffset - 1);
134 }
135 text.setFocus();
136 OS.ImageList_DragShowNolock(false);
137 text.setCaretOffset(newOffset);
138 OS.ImageList_DragShowNolock(true);
139 }
140 }
141 }
142 }
143 |
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