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1
11 package org.eclipse.jface.text;
12
13 import org.eclipse.swt.custom.StyleRange;
14 import org.eclipse.swt.custom.StyledText;
15 import org.eclipse.swt.custom.StyledTextContent;
16 import org.eclipse.swt.events.PaintEvent;
17 import org.eclipse.swt.events.PaintListener;
18 import org.eclipse.swt.graphics.Color;
19 import org.eclipse.swt.graphics.FontMetrics;
20 import org.eclipse.swt.graphics.GC;
21 import org.eclipse.swt.graphics.Point;
22
23
24
30 public class WhitespaceCharacterPainter implements IPainter, PaintListener {
31
32 private static final char SPACE_SIGN= '\u00b7';
33 private static final char IDEOGRAPHIC_SPACE_SIGN= '\u00b0';
34 private static final char TAB_SIGN= '\u00bb';
35 private static final char CARRIAGE_RETURN_SIGN= '\u00a4';
36 private static final char LINE_FEED_SIGN= '\u00b6';
37
38
39 private boolean fIsActive= false;
40
41 private ITextViewer fTextViewer;
42
43 private StyledText fTextWidget;
44
45 private boolean fIsAdvancedGraphicsPresent;
46
47
52 public WhitespaceCharacterPainter(ITextViewer textViewer) {
53 super();
54 fTextViewer= textViewer;
55 fTextWidget= textViewer.getTextWidget();
56 GC gc= new GC(fTextWidget);
57 gc.setAdvanced(true);
58 fIsAdvancedGraphicsPresent= gc.getAdvanced();
59 gc.dispose();
60 }
61
62
65 public void dispose() {
66 fTextViewer= null;
67 fTextWidget= null;
68 }
69
70
73 public void paint(int reason) {
74 IDocument document= fTextViewer.getDocument();
75 if (document == null) {
76 deactivate(false);
77 return;
78 }
79 if (!fIsActive) {
80 fIsActive= true;
81 fTextWidget.addPaintListener(this);
82 redrawAll(true);
83 } else if (reason == CONFIGURATION || reason == INTERNAL) {
84 redrawAll(false);
85 } else if (reason == TEXT_CHANGE) {
86 try {
88 IRegion lineRegion =
89 document.getLineInformationOfOffset(getDocumentOffset(fTextWidget.getCaretOffset()));
90 int widgetOffset= getWidgetOffset(lineRegion.getOffset());
91 int charCount= fTextWidget.getCharCount();
92 int redrawLength= Math.min(lineRegion.getLength(), charCount - widgetOffset);
93 if (widgetOffset >= 0 && redrawLength > 0) {
94 fTextWidget.redrawRange(widgetOffset, redrawLength, true);
95 }
96 } catch (BadLocationException e) {
97 }
99 }
100 }
101
102
105 public void deactivate(boolean redraw) {
106 if (fIsActive) {
107 fIsActive= false;
108 fTextWidget.removePaintListener(this);
109 if (redraw) {
110 redrawAll(true);
111 }
112 }
113 }
114
115
118 public void setPositionManager(IPaintPositionManager manager) {
119 }
121
122
125 public void paintControl(PaintEvent event) {
126 if (fTextWidget != null) {
127 handleDrawRequest(event.gc, event.x, event.y, event.width, event.height);
128 }
129 }
130
131
140 private void handleDrawRequest(GC gc, int x, int y, int w, int h) {
141 int lineCount= fTextWidget.getLineCount();
142 int startLine= (y + fTextWidget.getTopPixel()) / fTextWidget.getLineHeight();
143 int endLine= (y + h - 1 + fTextWidget.getTopPixel()) / fTextWidget.getLineHeight();
144 if (startLine <= endLine && startLine < lineCount) {
145 int startOffset= fTextWidget.getOffsetAtLine(startLine);
146 int endOffset =
147 endLine < lineCount - 1 ? fTextWidget.getOffsetAtLine(endLine + 1) : fTextWidget.getCharCount();
148
149 if (fIsAdvancedGraphicsPresent) {
150 int alpha= gc.getAlpha();
151 gc.setAlpha(100);
152 handleDrawRequest(gc, startOffset, endOffset);
153 gc.setAlpha(alpha);
154 } else
155 handleDrawRequest(gc, startOffset, endOffset);
156 }
157 }
158
159
166 private void handleDrawRequest(GC gc, int startOffset, int endOffset) {
167 StyledTextContent content= fTextWidget.getContent();
168 int length= endOffset - startOffset;
169 String  text= content.getTextRange(startOffset, length);
170 StyleRange styleRange= null;
171 Color fg= null;
172 Point selection= fTextWidget.getSelection();
173 StringBuffer visibleChar= new StringBuffer (10);
174 for (int textOffset= 0; textOffset <= length; ++textOffset) {
175 int delta= 0;
176 boolean eol= false;
177 if (textOffset < length) {
178 delta= 1;
179 char c= text.charAt(textOffset);
180 switch (c) {
181 case ' ' :
182 visibleChar.append(SPACE_SIGN);
183 break;
186 case '\u3000' : visibleChar.append(IDEOGRAPHIC_SPACE_SIGN);
188 break;
191 case '\t' :
192 visibleChar.append(TAB_SIGN);
193 break;
194 case '\r' :
195 visibleChar.append(CARRIAGE_RETURN_SIGN);
196 if (textOffset >= length - 1 || text.charAt(textOffset + 1) != '\n') {
197 eol= true;
198 break;
199 }
200 continue;
201 case '\n' :
202 visibleChar.append(LINE_FEED_SIGN);
203 eol= true;
204 break;
205 default :
206 delta= 0;
207 break;
208 }
209 }
210 if (visibleChar.length() > 0) {
211 int widgetOffset= startOffset + textOffset - visibleChar.length() + delta;
212 if (!eol || !isFoldedLine(content.getLineAtOffset(widgetOffset))) {
213 if (widgetOffset >= selection.x && widgetOffset < selection.y) {
214 fg= fTextWidget.getSelectionForeground();
215 } else if (styleRange == null || styleRange.start + styleRange.length <= widgetOffset) {
216 styleRange= fTextWidget.getStyleRangeAtOffset(widgetOffset);
217 if (styleRange == null || styleRange.foreground == null) {
218 fg= fTextWidget.getForeground();
219 } else {
220 fg= styleRange.foreground;
221 }
222 }
223 draw(gc, widgetOffset, visibleChar.toString(), fg);
224 }
225 visibleChar.delete(0, visibleChar.length());
226 }
227 }
228 }
229
230
236 private boolean isFoldedLine(int widgetLine) {
237 if (fTextViewer instanceof ITextViewerExtension5) {
238 ITextViewerExtension5 extension= (ITextViewerExtension5)fTextViewer;
239 int modelLine= extension.widgetLine2ModelLine(widgetLine);
240 int widgetLine2= extension.modelLine2WidgetLine(modelLine + 1);
241 return widgetLine2 == -1;
242 }
243 return false;
244 }
245
246
251 private void redrawAll(boolean redrawBackground) {
252 int startLine= fTextWidget.getTopPixel() / fTextWidget.getLineHeight();
253 int startOffset= fTextWidget.getOffsetAtLine(startLine);
254 int endLine= 1 + (fTextWidget.getTopPixel() + fTextWidget.getClientArea().height) / fTextWidget.getLineHeight();
255 int endOffset;
256 if (endLine >= fTextWidget.getLineCount()) {
257 endOffset= fTextWidget.getCharCount();
258 } else {
259 endOffset= fTextWidget.getOffsetAtLine(endLine);
260 }
261 if (startOffset < endOffset) {
262 endOffset= Math.min(endOffset + 2, fTextWidget.getCharCount());
264 int redrawOffset= startOffset;
265 int redrawLength= endOffset - redrawOffset;
266 fTextWidget.redrawRange(startOffset, redrawLength, redrawBackground);
267 }
268 }
269
270
278 private void draw(GC gc, int offset, String s, Color fg) {
279 int baseline= fTextWidget.getBaseline(offset);
281 FontMetrics fontMetrics= gc.getFontMetrics();
282 int fontBaseline= fontMetrics.getAscent() + fontMetrics.getLeading();
283 int baslineDelta= baseline - fontBaseline;
284
285 Point pos= fTextWidget.getLocationAtOffset(offset);
286 gc.setForeground(fg);
287 gc.drawString(s, pos.x, pos.y + baslineDelta, true);
288 }
289
290
296 private int getWidgetOffset(int documentOffset) {
297 if (fTextViewer instanceof ITextViewerExtension5) {
298 ITextViewerExtension5 extension= (ITextViewerExtension5)fTextViewer;
299 return extension.modelOffset2WidgetOffset(documentOffset);
300 }
301 IRegion visible= fTextViewer.getVisibleRegion();
302 int widgetOffset= documentOffset - visible.getOffset();
303 if (widgetOffset > visible.getLength()) {
304 return -1;
305 }
306 return widgetOffset;
307 }
308
309
315 private int getDocumentOffset(int widgetOffset) {
316 if (fTextViewer instanceof ITextViewerExtension5) {
317 ITextViewerExtension5 extension= (ITextViewerExtension5)fTextViewer;
318 return extension.widgetOffset2ModelOffset(widgetOffset);
319 }
320 IRegion visible= fTextViewer.getVisibleRegion();
321 if (widgetOffset > visible.getLength()) {
322 return -1;
323 }
324 return widgetOffset + visible.getOffset();
325 }
326
327 }
328 |
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