TreeCellEditor.java Source code

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Here is the source code for TreeCellEditor.java

Source

/*******************************************************************************
 * Copyright (c) 2000, 2004 IBM Corporation 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
//package org.eclipse.swt.snippets;
/*
 * TreeEditor example snippet: edit the text of a tree item (in place, fancy)
 *
 * For a list of all SWT example snippets see
 * http://www.eclipse.org/swt/snippets/
 */
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.TreeEditor;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;
import org.eclipse.swt.widgets.Tree;
import org.eclipse.swt.widgets.TreeItem;

public class TreeCellEditor {

    public static void main(String[] args) {
        final Display display = new Display();
        final Color black = display.getSystemColor(SWT.COLOR_BLACK);
        Shell shell = new Shell(display);
        shell.setLayout(new FillLayout());
        final Tree tree = new Tree(shell, SWT.BORDER);
        for (int i = 0; i < 16; i++) {
            TreeItem itemI = new TreeItem(tree, SWT.NONE);
            itemI.setText("Item " + i);
            for (int j = 0; j < 16; j++) {
                TreeItem itemJ = new TreeItem(itemI, SWT.NONE);
                itemJ.setText("Item " + j);
            }
        }
        final TreeItem[] lastItem = new TreeItem[1];
        final TreeEditor editor = new TreeEditor(tree);
        tree.addListener(SWT.Selection, new Listener() {
            public void handleEvent(Event event) {
                final TreeItem item = (TreeItem) event.item;
                if (item != null && item == lastItem[0]) {
                    boolean isCarbon = SWT.getPlatform().equals("carbon");
                    final Composite composite = new Composite(tree, SWT.NONE);
                    if (!isCarbon)
                        composite.setBackground(black);
                    final Text text = new Text(composite, SWT.NONE);
                    final int inset = isCarbon ? 0 : 1;
                    composite.addListener(SWT.Resize, new Listener() {
                        public void handleEvent(Event e) {
                            Rectangle rect = composite.getClientArea();
                            text.setBounds(rect.x + inset, rect.y + inset, rect.width - inset * 2,
                                    rect.height - inset * 2);
                        }
                    });
                    Listener textListener = new Listener() {
                        public void handleEvent(final Event e) {
                            switch (e.type) {
                            case SWT.FocusOut:
                                item.setText(text.getText());
                                composite.dispose();
                                break;
                            case SWT.Verify:
                                String newText = text.getText();
                                String leftText = newText.substring(0, e.start);
                                String rightText = newText.substring(e.end, newText.length());
                                GC gc = new GC(text);
                                Point size = gc.textExtent(leftText + e.text + rightText);
                                gc.dispose();
                                size = text.computeSize(size.x, SWT.DEFAULT);
                                editor.horizontalAlignment = SWT.LEFT;
                                Rectangle itemRect = item.getBounds(), rect = tree.getClientArea();
                                editor.minimumWidth = Math.max(size.x, itemRect.width) + inset * 2;
                                int left = itemRect.x, right = rect.x + rect.width;
                                editor.minimumWidth = Math.min(editor.minimumWidth, right - left);
                                editor.minimumHeight = size.y + inset * 2;
                                editor.layout();
                                break;
                            case SWT.Traverse:
                                switch (e.detail) {
                                case SWT.TRAVERSE_RETURN:
                                    item.setText(text.getText());
                                    // FALL THROUGH
                                case SWT.TRAVERSE_ESCAPE:
                                    composite.dispose();
                                    e.doit = false;
                                }
                                break;
                            }
                        }
                    };
                    text.addListener(SWT.FocusOut, textListener);
                    text.addListener(SWT.Traverse, textListener);
                    text.addListener(SWT.Verify, textListener);
                    editor.setEditor(composite, item);
                    text.setText(item.getText());
                    text.selectAll();
                    text.setFocus();
                }
                lastItem[0] = item;
            }
        });
        shell.pack();
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }
        display.dispose();
    }
}