Java tutorial
/******************************************************************************* * Copyright (c) 2007, 2011 Wind River Systems, Inc. and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * Anton Leherbauer (Wind River Systems) - initial API and implementation *******************************************************************************/ package org.eclipse.cdt.internal.ui.text; import org.eclipse.jface.preference.IPreferenceStore; import org.eclipse.jface.preference.PreferenceConverter; import org.eclipse.jface.resource.JFaceResources; import org.eclipse.jface.text.Document; import org.eclipse.jface.text.IDocument; import org.eclipse.jface.text.IInformationControlExtension2; import org.eclipse.jface.text.source.ISourceViewer; import org.eclipse.jface.text.source.SourceViewer; import org.eclipse.swt.SWT; import org.eclipse.swt.custom.StyledText; import org.eclipse.swt.events.DisposeEvent; import org.eclipse.swt.events.DisposeListener; import org.eclipse.swt.events.KeyEvent; import org.eclipse.swt.events.KeyListener; import org.eclipse.swt.graphics.Color; import org.eclipse.swt.graphics.Font; import org.eclipse.swt.graphics.GC; import org.eclipse.swt.graphics.Point; import org.eclipse.swt.graphics.RGB; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Label; import org.eclipse.swt.widgets.Shell; import org.eclipse.cdt.ui.CUIPlugin; import org.eclipse.cdt.ui.PreferenceConstants; import org.eclipse.cdt.ui.text.ICPartitions; import org.eclipse.cdt.internal.ui.editor.CSourceViewer; import org.eclipse.cdt.internal.ui.text.c.hover.SourceViewerInformationControl; /** * Abstract class for "quick" source views in light-weight controls. * * @since 5.0 */ public abstract class AbstractSourceViewerInformationControl extends org.eclipse.jface.text.AbstractInformationControl implements IInformationControlExtension2, DisposeListener { private ISourceViewer fSourceViewer; private Color fBackgroundColor; private boolean fIsSystemBackgroundColor = true; private Font fTextFont; private StyledText fText; private Label fTitleLabel; /** * Creates a source viewer information control with the given shell as parent. The given * styles are applied to the shell and the source viewer. * * @param parent the parent shell * @param statusFieldText */ public AbstractSourceViewerInformationControl(Shell parent, String statusFieldText) { super(parent, statusFieldText); // Create all controls create(); } /** * Creates a source viewer information control with the given shell as parent. The given * styles are applied to the shell and the source viewer. * * @param parent the parent shell * @param isResizable whether the control should be resizable */ public AbstractSourceViewerInformationControl(Shell parent, boolean isResizable) { super(parent, isResizable); // Create all controls create(); } /** * @return <code>true</code> if the control should have a title label */ protected boolean hasHeader() { return false; } private void initializeColors() { IPreferenceStore store = CUIPlugin.getDefault().getPreferenceStore(); RGB bgRGB; if (store.getBoolean(PreferenceConstants.EDITOR_SOURCE_HOVER_BACKGROUND_COLOR_SYSTEM_DEFAULT)) { bgRGB = SourceViewerInformationControl.getVisibleBackgroundColor(getShell().getDisplay()); } else { bgRGB = PreferenceConverter.getColor(store, PreferenceConstants.EDITOR_SOURCE_HOVER_BACKGROUND_COLOR); } if (bgRGB != null) { fBackgroundColor = new Color(getShell().getDisplay(), bgRGB); fIsSystemBackgroundColor = false; } else { fBackgroundColor = getShell().getDisplay().getSystemColor(SWT.COLOR_INFO_BACKGROUND); fIsSystemBackgroundColor = true; } } @Override public void createContent(Composite parent) { Composite content = new Composite(parent, SWT.NONE); final GridLayout gridLayout = new GridLayout(); gridLayout.marginWidth = 0; gridLayout.marginHeight = 0; gridLayout.verticalSpacing = 0; content.setLayout(gridLayout); if (hasHeader()) { createTitleLabel(content); } fSourceViewer = createSourceViewer(content, SWT.NONE); final StyledText text = fSourceViewer.getTextWidget(); text.addKeyListener(new KeyListener() { @Override public void keyPressed(KeyEvent e) { if (e.character == 0x1B) // ESC dispose(); } @Override public void keyReleased(KeyEvent e) { // do nothing } }); addDisposeListener(this); } protected final ISourceViewer createSourceViewer(Composite parent, int style) { IPreferenceStore store = CUIPlugin.getDefault().getCombinedPreferenceStore(); SourceViewer sourceViewer = new CSourceViewer(parent, null, null, false, style, store); CTextTools tools = CUIPlugin.getDefault().getTextTools(); sourceViewer.configure(new SimpleCSourceViewerConfiguration(tools.getColorManager(), store, null, ICPartitions.C_PARTITIONING, false)); sourceViewer.setEditable(false); fText = sourceViewer.getTextWidget(); GridData gd = new GridData(GridData.BEGINNING | GridData.FILL_BOTH); fText.setLayoutData(gd); initializeColors(); fText.setForeground(parent.getDisplay().getSystemColor(SWT.COLOR_INFO_FOREGROUND)); fText.setBackground(fBackgroundColor); fTextFont = JFaceResources.getFont(PreferenceConstants.EDITOR_TEXT_FONT); fText.setFont(fTextFont); return sourceViewer; } private void createTitleLabel(Composite parent) { fTitleLabel = new Label(parent, SWT.LEFT); fTitleLabel.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); Label separator = new Label(parent, SWT.SEPARATOR | SWT.HORIZONTAL); separator.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); fTitleLabel.setFont(JFaceResources.getDialogFont()); Display display = parent.getDisplay(); Color foreground = display.getSystemColor(SWT.COLOR_INFO_FOREGROUND); Color background = display.getSystemColor(SWT.COLOR_INFO_BACKGROUND); fTitleLabel.setForeground(foreground); fTitleLabel.setBackground(background); } public void setTitleText(String titleText) { if (fTitleLabel != null) { fTitleLabel.setText(titleText); } } /** * Returns the source viewer. * * @return the source viewer. */ protected final ISourceViewer getSourceViewer() { return fSourceViewer; } @Override public void setInformation(String content) { if (content == null) { fSourceViewer.setDocument(null); return; } IDocument doc = new Document(content); CUIPlugin.getDefault().getTextTools().setupCDocument(doc); fSourceViewer.setDocument(doc); } @Override public void setInput(Object input) { if (input instanceof String) setInformation((String) input); else setInformation(null); } @Override public final void dispose() { if (!fIsSystemBackgroundColor) { fBackgroundColor.dispose(); } super.dispose(); } /** * {@inheritDoc} * @param event can be null * <p> * Subclasses may extend. * </p> */ @Override public void widgetDisposed(DisposeEvent event) { fSourceViewer = null; } @Override public boolean hasContents() { return fSourceViewer != null && fSourceViewer.getDocument() != null; } @Override public void setFocus() { super.setFocus(); fSourceViewer.getTextWidget().setFocus(); } @Override public Point computeSizeConstraints(int widthInChars, int heightInChars) { GC gc = new GC(fText); gc.setFont(fTextFont); int width = gc.getFontMetrics().getAverageCharWidth(); int height = gc.getFontMetrics().getHeight(); gc.dispose(); return new Point(widthInChars * width, heightInChars * height); } @Override public Point computeSizeHint() { // compute the preferred size int x = SWT.DEFAULT; int y = SWT.DEFAULT; Point size = getShell().computeSize(x, y); Point constraints = getSizeConstraints(); if (constraints != null) { if (size.x > constraints.x) x = constraints.x; if (size.y > constraints.y) y = constraints.y; } // recompute using the constraints if the preferred size is larger than the constraints if (x != SWT.DEFAULT || y != SWT.DEFAULT) size = getShell().computeSize(x, y, false); return size; } }