X-Git-Url: http://git.phpeclipse.com

diff --git a/net.sourceforge.phpeclipse/src/net/sourceforge/phpeclipse/phpeditor/LinePainter.java b/net.sourceforge.phpeclipse/src/net/sourceforge/phpeclipse/phpeditor/LinePainter.java
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index 0000000..a3b7167
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+++ b/net.sourceforge.phpeclipse/src/net/sourceforge/phpeclipse/phpeditor/LinePainter.java
@@ -0,0 +1,172 @@
+package net.sourceforge.phpeclipse.phpeditor;
+
+/*
+ * (c) Copyright IBM Corp. 2000, 2001.
+ * All Rights Reserved.
+ */
+
+import org.eclipse.jface.text.BadLocationException;
+import org.eclipse.jface.text.IDocument;
+import org.eclipse.jface.text.Position;
+import org.eclipse.jface.text.source.ISourceViewer;
+import org.eclipse.swt.custom.LineBackgroundEvent;
+import org.eclipse.swt.custom.LineBackgroundListener;
+import org.eclipse.swt.custom.StyledText;
+import org.eclipse.swt.graphics.Color;
+import org.eclipse.swt.graphics.Point;
+
+public class LinePainter implements IPainter, LineBackgroundListener {
+
+	private final ISourceViewer fViewer;
+	private Color fHighlightColor;
+	private IPositionManager fPositionManager;
+
+	// positions to keep track of beginning and end of line to be painted or cleared
+	private Position fCurrentLine= new Position(0, 0);
+	private Position fLastLine= new Position(0, 0);
+	// used to keep track of the last line painted
+	private int fLastLineNumber= -1;
+	private boolean fIsActive;
+
+	public LinePainter(ISourceViewer sourceViewer) {
+		fViewer= sourceViewer;
+	}
+
+	public void setHighlightColor(Color highlightColor) {
+		fHighlightColor= highlightColor;
+	}
+
+	/*
+	 * @see LineBackgroundListener#lineGetBackground(LineBackgroundEvent)
+	 */
+	public void lineGetBackground(LineBackgroundEvent event) {
+		// don't use cached line information because of asynch painting
+
+		StyledText textWidget= fViewer.getTextWidget();
+		if (textWidget != null) {
+			
+			int caret= textWidget.getCaretOffset();
+			int length= event.lineText.length();
+
+			if (event.lineOffset <= caret && caret <= event.lineOffset + length)
+				event.lineBackground= fHighlightColor;
+			else
+				event.lineBackground= textWidget.getBackground();
+		}
+	}
+
+	private boolean updateHighlightLine() {
+		try {
+
+			IDocument document= fViewer.getDocument();
+
+			int offset= fViewer.getTextWidget().getCaretOffset() + fViewer.getVisibleRegion().getOffset();
+			int lineNumber= document.getLineOfOffset(offset);
+						
+			// redraw if the current line number is different from the last line number we painted
+			// initially fLastLineNumber is -1
+			if (lineNumber != fLastLineNumber) {
+				
+				fLastLine.offset= fCurrentLine.offset;
+				fLastLine.length= fCurrentLine.length;
+				fLastLine.isDeleted= fCurrentLine.isDeleted;
+
+				fCurrentLine.isDeleted= false;
+				fCurrentLine.offset= document.getLineOffset(lineNumber);
+				if (lineNumber == document.getNumberOfLines() - 1)
+					fCurrentLine.length= document.getLength() - fCurrentLine.offset;
+				else
+					fCurrentLine.length=	document.getLineOffset(lineNumber + 1) - fCurrentLine.offset;
+				
+				fLastLineNumber= lineNumber;
+				return true;
+				
+			}
+			
+		} catch (BadLocationException e) {
+		}
+
+		return false;
+	}
+
+	private void drawHighlightLine(Position position, int visibleOffset) {
+		StyledText textWidget= fViewer.getTextWidget();
+		
+		// if the position that is about to be drawn was deleted then we can't
+		if (position.isDeleted())
+			return;		
+		
+		int delta= position.offset - visibleOffset;
+		if (0 <= delta && delta <= fViewer.getVisibleRegion().getLength()) {
+			Point upperLeft= textWidget.getLocationAtOffset(delta);
+			int width= textWidget.getClientArea().width + textWidget.getHorizontalPixel();
+			int height= textWidget.getLineHeight();
+			textWidget.redraw(upperLeft.x, upperLeft.y, width, height, false);
+		}
+	}
+
+	/*
+	 * @see IPainter#deactivate(boolean)
+	 */
+	public void deactivate(boolean redraw) {
+		if (fIsActive) {
+			fIsActive= false;
+			
+			/* on turning off the feature one has to paint the currently 
+			 * highlighted line with the standard background color 
+			 */
+			if (redraw)
+				drawHighlightLine(fCurrentLine, fViewer.getVisibleRegion().getOffset());
+				
+			fViewer.getTextWidget().removeLineBackgroundListener(this);
+			
+			if (fPositionManager != null)
+				fPositionManager.removeManagedPosition(fCurrentLine);
+				
+			fLastLineNumber= -1;
+		}
+	}
+
+	/*
+	 * @see IPainter#dispose()
+	 */
+	public void dispose() {
+	}
+
+	/*
+	 * @see IPainter#paint(int)
+	 */
+	public void paint(int reason) {
+		
+		// check selection
+		Point selection= fViewer.getTextWidget().getSelectionRange();
+		if (selection.y > 0) {
+			deactivate(true);
+			return;
+		}
+		
+		// initialization
+		if (!fIsActive) {
+			fViewer.getTextWidget().addLineBackgroundListener(this);
+			fPositionManager.addManagedPosition(fCurrentLine);
+			fIsActive= true;
+		}
+		
+		//redraw line highlight only if it hasn't been drawn yet on the respective line
+		if (updateHighlightLine()) {
+			// used to handle segmented view of source files
+			int visibleRegionOffset= fViewer.getVisibleRegion().getOffset();
+			// clear last line
+			drawHighlightLine(fLastLine, visibleRegionOffset);
+			// draw new line
+			drawHighlightLine(fCurrentLine, visibleRegionOffset);
+		}
+	}
+
+	/*
+	 * @see IPainter#setPositionManager(IPositionManager)
+	 */
+	public void setPositionManager(IPositionManager manager) {
+		fPositionManager = manager;
+	}
+}
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