/*******************************************************************************
* Copyright (c) 2000, 2011 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.custom;
import org.eclipse.swt.*;
import org.eclipse.swt.events.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.widgets.*;
/**
*
* A TreeEditor is a manager for a Control that appears above a cell in a Tree and tracks with the
* moving and resizing of that cell. It can be used to display a text widget above a cell
* in a Tree so that the user can edit the contents of that cell. It can also be used to display
* a button that can launch a dialog for modifying the contents of the associated cell.
*
* <p> Here is an example of using a TreeEditor:
* <code><pre>
* final Tree tree = new Tree(shell, SWT.BORDER);
* for (int i = 0; i < 3; i++) {
* TreeItem item = new TreeItem(tree, SWT.NONE);
* item.setText("item " + i);
* for (int j = 0; j < 3; j++) {
* TreeItem subItem = new TreeItem(item, SWT.NONE);
* subItem.setText("item " + i + " " + j);
* }
* }
*
* final TreeEditor editor = new TreeEditor(tree);
* //The editor must have the same size as the cell and must
* //not be any smaller than 50 pixels.
* editor.horizontalAlignment = SWT.LEFT;
* editor.grabHorizontal = true;
* editor.minimumWidth = 50;
*
* tree.addSelectionListener(new SelectionAdapter() {
* public void widgetSelected(SelectionEvent e) {
* // Clean up any previous editor control
* Control oldEditor = editor.getEditor();
* if (oldEditor != null) oldEditor.dispose();
*
* // Identify the selected row
* TreeItem item = (TreeItem)e.item;
* if (item == null) return;
*
* // The control that will be the editor must be a child of the Tree
* Text newEditor = new Text(tree, SWT.NONE);
* newEditor.setText(item.getText());
* newEditor.addModifyListener(new ModifyListener() {
* public void modifyText(ModifyEvent e) {
* Text text = (Text)editor.getEditor();
* editor.getItem().setText(text.getText());
* }
* });
* newEditor.selectAll();
* newEditor.setFocus();
* editor.setEditor(newEditor, item);
* }
* });
* </pre></code>
*
* @see <a href="http://www.eclipse.org/swt/snippets/#treeeditor">TreeEditor snippets</a>
* @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
*/
public class TreeEditor extends ControlEditor {
Tree tree;
TreeItem item;
int column = 0;
ControlListener columnListener;
TreeListener treeListener;
Runnable timer;
static final int TIMEOUT = 1500;
/**
* Creates a TreeEditor for the specified Tree.
*
* @param tree the Tree Control above which this editor will be displayed
*
*/
public TreeEditor (Tree tree) {
super(tree);
this.tree = tree;
columnListener = new ControlListener() {
public void controlMoved(ControlEvent e){
layout();
}
public void controlResized(ControlEvent e){
layout();
}
};
timer = new Runnable () {
public void run() {
layout ();
}
};
treeListener = new TreeListener () {
final Runnable runnable = new Runnable() {
public void run() {
if (editor == null || editor.isDisposed()) return;
if (TreeEditor.this.tree.isDisposed()) return;
layout();
editor.setVisible(true);
}
};
public void treeCollapsed(TreeEvent e) {
if (editor == null || editor.isDisposed ()) return;
editor.setVisible(false);
e.display.asyncExec(runnable);
}
public void treeExpanded(TreeEvent e) {
if (editor == null || editor.isDisposed ()) return;
editor.setVisible(false);
e.display.asyncExec(runnable);
}
};
tree.addTreeListener(treeListener);
// To be consistent with older versions of SWT, grabVertical defaults to true
grabVertical = true;
}
@Override
Rectangle computeBounds () {
if (item == null || column == -1 || item.isDisposed()) return new Rectangle(0, 0, 0, 0);
Rectangle cell = item.getBounds(column);
Rectangle rect = item.getImageBounds(column);
cell.x = rect.x + rect.width;
cell.width -= rect.width;
Rectangle area = tree.getClientArea();
if (cell.x < area.x + area.width) {
if (cell.x + cell.width > area.x + area.width) {
cell.width = area.x + area.width - cell.x;
}
}
Rectangle editorRect = new Rectangle(cell.x, cell.y, minimumWidth, minimumHeight);
if (grabHorizontal) {
if (tree.getColumnCount() == 0) {
// Bounds of tree item only include the text area - stretch out to include
// entire client area
cell.width = area.x + area.width - cell.x;
}
editorRect.width = Math.max(cell.width, minimumWidth);
}
if (grabVertical) {
editorRect.height = Math.max(cell.height, minimumHeight);
}
if (horizontalAlignment == SWT.RIGHT) {
editorRect.x += cell.width - editorRect.width;
} else if (horizontalAlignment == SWT.LEFT) {
// do nothing - cell.x is the right answer
} else { // default is CENTER
editorRect.x += (cell.width - editorRect.width)/2;
}
// don't let the editor overlap with the +/- of the tree
editorRect.x = Math.max(cell.x, editorRect.x);
if (verticalAlignment == SWT.BOTTOM) {
editorRect.y += cell.height - editorRect.height;
} else if (verticalAlignment == SWT.TOP) {
// do nothing - cell.y is the right answer
} else { // default is CENTER
editorRect.y += (cell.height - editorRect.height)/2;
}
return editorRect;
}
/**
* Removes all associations between the TreeEditor and the row in the tree. The
* tree and the editor Control are <b>not</b> disposed.
*/
@Override
public void dispose () {
if (tree != null && !tree.isDisposed()) {
if (this.column > -1 && this.column < tree.getColumnCount()){
TreeColumn treeColumn = tree.getColumn(this.column);
treeColumn.removeControlListener(columnListener);
}
if (treeListener != null) tree.removeTreeListener(treeListener);
}
columnListener = null;
treeListener = null;
tree = null;
item = null;
column = 0;
timer = null;
super.dispose();
}
/**
* Returns the zero based index of the column of the cell being tracked by this editor.
*
* @return the zero based index of the column of the cell being tracked by this editor
*
* @since 3.1
*/
public int getColumn () {
return column;
}
/**
* Returns the TreeItem for the row of the cell being tracked by this editor.
*
* @return the TreeItem for the row of the cell being tracked by this editor
*/
public TreeItem getItem () {
return item;
}
void resize () {
layout();
/*
* On some platforms, the table scrolls when an item that
* is partially visible at the bottom of the table is
* selected. Ensure that the correct row is edited by
* laying out one more time in a timerExec().
*/
if (tree != null) {
Display display = tree.getDisplay();
display.timerExec(-1, timer);
display.timerExec(TIMEOUT, timer);
}
}
/**
* Sets the zero based index of the column of the cell being tracked by this editor.
*
* @param column the zero based index of the column of the cell being tracked by this editor
*
* @since 3.1
*/
public void setColumn(int column) {
int columnCount = tree.getColumnCount();
// Separately handle the case where the tree has no TreeColumns.
// In this situation, there is a single default column.
if (columnCount == 0) {
this.column = (column == 0) ? 0 : -1;
resize();
return;
}
if (this.column > -1 && this.column < columnCount){
TreeColumn treeColumn = tree.getColumn(this.column);
treeColumn.removeControlListener(columnListener);
this.column = -1;
}
if (column < 0 || column >= tree.getColumnCount()) return;
this.column = column;
TreeColumn treeColumn = tree.getColumn(this.column);
treeColumn.addControlListener(columnListener);
resize();
}
/**
* Specifies the <code>TreeItem</code> that is to be edited.
*
* @param item the item to be edited
*/
public void setItem (TreeItem item) {
this.item = item;
resize();
}
/**
* Specify the Control that is to be displayed and the cell in the tree that it is to be positioned above.
*
* <p>Note: The Control provided as the editor <b>must</b> be created with its parent being the Tree control
* specified in the TreeEditor constructor.
*
* @param editor the Control that is displayed above the cell being edited
* @param item the TreeItem for the row of the cell being tracked by this editor
* @param column the zero based index of the column of the cell being tracked by this editor
*
* @since 3.1
*/
public void setEditor (Control editor, TreeItem item, int column) {
setItem(item);
setColumn(column);
setEditor(editor);
}
@Override
public void setEditor (Control editor) {
super.setEditor(editor);
resize();
}
/**
* Specify the Control that is to be displayed and the cell in the tree that it is to be positioned above.
*
* <p>Note: The Control provided as the editor <b>must</b> be created with its parent being the Tree control
* specified in the TreeEditor constructor.
*
* @param editor the Control that is displayed above the cell being edited
* @param item the TreeItem for the row of the cell being tracked by this editor
*/
public void setEditor (Control editor, TreeItem item) {
setItem(item);
setEditor(editor);
}
@Override
public void layout () {
if (tree == null || tree.isDisposed()) return;
if (item == null || item.isDisposed()) return;
int columnCount = tree.getColumnCount();
if (columnCount == 0 && column != 0) return;
if (columnCount > 0 && (column < 0 || column >= columnCount)) return;
super.layout();
}
}