Java Code Examples for org.eclipse.jface.text.ITextSelection#isEmpty()

/**
 * Returns if the current selection is valid, i.e. whether it is empty and
 * the caret in the whitespace at the start of a line, or covers multiple
 * lines.
 * 
 * @return <code>true</code> if the selection is valid for an indent
 *         operation
 */
private boolean isValidSelection() {
	ITextSelection selection = getSelection();
	if (selection.isEmpty())
		return false;

	int offset = selection.getOffset();
	int length = selection.getLength();

	IDocument document = getDocument();
	if (document == null)
		return false;

	try {
		IRegion firstLine = document.getLineInformationOfOffset(offset);
		int lineOffset = firstLine.getOffset();

		// either the selection has to be empty and the caret in the WS at
		// the line start
		// or the selection has to extend over multiple lines
		if (length == 0)
			return document.get(lineOffset, offset - lineOffset).trim().length() == 0;
		else
			// return lineOffset + firstLine.getLength() < offset + length;
			return false; // only enable for empty selections for now

	} catch (BadLocationException e) {
	}

	return false;
}
 

/**
	 * Returns if the current selection is valid, i.e. whether it is empty and the caret in the
	 * whitespace at the start of a line, or covers multiple lines.
	 *
	 * @return <code>true</code> if the selection is valid for an indent operation
	 */
	private boolean isValidSelection() {
		ITextSelection selection= getSelection();
		if (selection.isEmpty())
			return false;

		int offset= selection.getOffset();
		int length= selection.getLength();

		IDocument document= getDocument();
		if (document == null)
			return false;

		try {
			IRegion firstLine= document.getLineInformationOfOffset(offset);
			int lineOffset= firstLine.getOffset();

			// either the selection has to be empty and the caret in the WS at the line start
			// or the selection has to extend over multiple lines
			if (length == 0)
				return document.get(lineOffset, offset - lineOffset).trim().length() == 0;
			else
//				return lineOffset + firstLine.getLength() < offset + length;
				return false; // only enable for empty selections for now

		} catch (BadLocationException e) {
		}

		return false;
	}
 

@Override
public void runWithEvent(Event event) {
	ITextViewer viewer = getTextViewer();
	if (viewer == null)
		return;

	if (!canModifyViewer())
		return;

	// get involved objects

	IDocument document= viewer.getDocument();
	if (document == null)
		return;

	StyledText widget= viewer.getTextWidget();
	if (widget == null)
		return;

	// get selection
	ITextSelection sel= (ITextSelection) viewer.getSelectionProvider().getSelection();
	if (sel.isEmpty())
		return;

	ITextSelection skippedLine= getSkippedLine(document, sel);
	if (skippedLine == null)
		return;

	try {

		ITextSelection movingArea= getMovingSelection(document, sel, viewer);

		// if either the skipped line or the moving lines are outside the widget's
		// visible area, bail out
		if (!containedByVisibleRegion(movingArea, viewer) || !containedByVisibleRegion(skippedLine, viewer))
			return;

		// get the content to be moved around: the moving (selected) area and the skipped line
		String moving= movingArea.getText();
		String skipped= skippedLine.getText();
		if (moving == null || skipped == null || document.getLength() == 0)
			return;

		String delim;
		String insertion;
		int offset, deviation;
		if (fUpwards) {
			delim= document.getLineDelimiter(skippedLine.getEndLine());
			if (fCopy) {
				delim= TextUtilities.getDefaultLineDelimiter(document);
				insertion= moving + delim;
				offset= movingArea.getOffset();
				deviation= 0;
			} else {
				Assert.isNotNull(delim);
				insertion= moving + delim + skipped;
				offset= skippedLine.getOffset();
				deviation= -skippedLine.getLength() - delim.length();
			}
		} else {
			delim= document.getLineDelimiter(movingArea.getEndLine());
			if (fCopy) {
				if (delim == null) {
					delim= TextUtilities.getDefaultLineDelimiter(document);
					insertion= delim + moving;
				} else {
					insertion= moving + delim;
				}
				offset= skippedLine.getOffset();
				deviation= movingArea.getLength() + delim.length();
			} else {
				Assert.isNotNull(delim);
				insertion= skipped + delim + moving;
				offset= movingArea.getOffset();
				deviation= skipped.length() + delim.length();
			}
		}

		// modify the document
		beginCompoundEdit();
		if (fCopy) {
			document.replace(offset, 0, insertion);
		} else {
			document.replace(offset, insertion.length(), insertion);
		}

		// move the selection along
		int selOffset= movingArea.getOffset() + deviation;
		int selLength= movingArea.getLength() + (fAddDelimiter ? delim.length() : 0);
		if (! (viewer instanceof ITextViewerExtension5))
			selLength= Math.min(selLength, viewer.getVisibleRegion().getOffset() + viewer.getVisibleRegion().getLength() - selOffset);
		else {
			// TODO need to check what is necessary in the projection case
		}
		selectAndReveal(viewer, selOffset, selLength);
	} catch (BadLocationException x) {
		// won't happen without concurrent modification - bail out
		return;
	}
}
 

private boolean checkEnabled(ITextSelection selection) {
	if (selection == null || selection.isEmpty())
		return false;

	return PropertyKeyHyperlinkDetector.checkEnabled(fEditor, selection.getOffset());
}
 

@Override
protected boolean isValidSelection(ITextSelection selection) {
	return selection != null && !selection.isEmpty() && selection.getLength() > 0;
}
 

@Override
protected boolean isValidSelection(ITextSelection selection) {
	return selection != null && !selection.isEmpty();
}