TextTreeEditor.java Source code

Introduction

Here is the source code for TextTreeEditor.java

Source

import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.*;
import org.eclipse.swt.events.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.widgets.*;

/**
 * This class demonstrates TreeEditor
 */
public class TextTreeEditor {
    // Constant for how many items to create at each level
    private static final int NUM = 3;

    /**
     * Runs the //Send questions, comments, bug reports, etc. to the authors:
        
    //Rob Warner (rwarner@interspatial.com)
    //Robert Harris (rbrt_harris@yahoo.com)application
     */
    public void run() {
        Display display = new Display();
        Shell shell = new Shell(display);
        shell.setText("Text Tree Editor");
        createContents(shell);
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch()) {
                display.sleep();
            }
        }
        display.dispose();
    }

    /**
     * Creates the contents of the main window
     * 
     * @param shell the main window
     */
    public void createContents(Shell shell) {
        shell.setLayout(new FillLayout());

        // Create the tree
        final Tree tree = new Tree(shell, SWT.SINGLE);

        // Fill the tree with data
        for (int i = 0; i < NUM; i++) {
            TreeItem iItem = new TreeItem(tree, SWT.NONE);
            iItem.setText("Item " + (i + 1));
            for (int j = 0; j < NUM; j++) {
                TreeItem jItem = new TreeItem(iItem, SWT.NONE);
                jItem.setText("Sub Item " + (j + 1));
                for (int k = 0; k < NUM; k++) {
                    new TreeItem(jItem, SWT.NONE).setText("Sub Sub Item " + (k + 1));
                }
                jItem.setExpanded(true);
            }
            iItem.setExpanded(true);
        }

        // Create the editor and set its attributes
        final TreeEditor editor = new TreeEditor(tree);
        editor.horizontalAlignment = SWT.LEFT;
        editor.grabHorizontal = true;

        // Add a key listener to the tree that listens for F2.
        // If F2 is pressed, we do the editing
        tree.addKeyListener(new KeyAdapter() {
            public void keyPressed(KeyEvent event) {
                // Make sure one and only one item is selected when F2 is pressed
                if (event.keyCode == SWT.F2 && tree.getSelectionCount() == 1) {
                    // Determine the item to edit
                    final TreeItem item = tree.getSelection()[0];

                    // Create a text field to do the editing
                    final Text text = new Text(tree, SWT.NONE);
                    text.setText(item.getText());
                    text.selectAll();
                    text.setFocus();

                    // If the text field loses focus, set its text into the tree
                    // and end the editing session
                    text.addFocusListener(new FocusAdapter() {
                        public void focusLost(FocusEvent event) {
                            item.setText(text.getText());
                            text.dispose();
                        }
                    });

                    // If they hit Enter, set the text into the tree and end the editing
                    // session. If they hit Escape, ignore the text and end the editing
                    // session
                    text.addKeyListener(new KeyAdapter() {
                        public void keyPressed(KeyEvent event) {
                            switch (event.keyCode) {
                            case SWT.CR:
                                // Enter hit--set the text into the tree and drop through
                                item.setText(text.getText());
                            case SWT.ESC:
                                // End editing session
                                text.dispose();
                                break;
                            }
                        }
                    });

                    // Set the text field into the editor
                    editor.setEditor(text, item);
                }
            }
        });
    }

    /**
     * The application entry point
     * 
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        new TextTreeEditor().run();
    }
}