org.eclipse.swt.custom

Class ControlEditor

java.lang.Object

org.eclipse.swt.custom.ControlEditor

Direct Known Subclasses:

TableEditor, TableTreeEditor, TreeEditor

public class ControlEditor
extends java.lang.Object

A ControlEditor is a manager for a Control that appears above a composite and tracks with the moving and resizing of that composite. It can be used to display one control above another control. This could be used when editing a control that does not have editing capabilities by using a text editor or for launching a dialog by placing a button above a control.

Here is an example of using a ControlEditor:

 Canvas canvas = new Canvas(shell, SWT.BORDER);
 canvas.setBounds(10, 10, 300, 300);    
 Color color = new Color(null, 255, 0, 0);
 canvas.setBackground(color);
 ControlEditor editor = new ControlEditor (canvas);
 // The editor will be a button in the bottom right corner of the canvas.
 // When selected, it will launch a Color dialog that will change the background 
 // of the canvas.
 Button button = new Button(canvas, SWT.PUSH);
 button.setText("Select Color...");
 button.addSelectionListener (new SelectionAdapter() {
        public void widgetSelected(SelectionEvent e) {
                ColorDialog dialog = new ColorDialog(shell);
                dialog.open();
                RGB rgb = dialog.getRGB();
                if (rgb != null) {
                        if (color != null) color.dispose();
                        color = new Color(null, rgb);
                        canvas.setBackground(color);
                }
                
        }
 });

 editor.horizontalAlignment = SWT.RIGHT;
 editor.verticalAlignment = SWT.BOTTOM;
 editor.grabHorizontal = false;
 editor.grabVertical = false;
 Point size = button.computeSize(SWT.DEFAULT, SWT.DEFAULT);
 editor.minimumWidth = size.x;
 editor.minimumHeight = size.y;
 editor.setEditor (button);
 

See Also:

Sample code and further information

Structure Diagram

Field Summary

Fields

Modifier and Type	Field and Description
private Listener	controlListener
(package private) Control	editor
private static int[]	EVENTS
boolean	grabHorizontal Specifies whether the editor should be sized to use the entire width of the control.
boolean	grabVertical Specifies whether the editor should be sized to use the entire height of the control.
private boolean	hadFocus
int	horizontalAlignment Specifies how the editor should be aligned relative to the control.
int	minimumHeight Specifies the minimum height the editor can have.
int	minimumWidth Specifies the minimum width the editor can have.
(package private) Composite	parent
private Listener	scrollbarListener
int	verticalAlignment Specifies how the editor should be aligned relative to the control.

Constructor Summary

Constructors

Constructor and Description
ControlEditor(Composite parent) Creates a ControlEditor for the specified Composite.

Method Summary

Methods

Modifier and Type	Method and Description
(package private) Rectangle	computeBounds()
void	dispose() Removes all associations between the Editor and the underlying composite.
Control	getEditor() Returns the Control that is displayed above the composite being edited.
void	layout() Lays out the control within the underlying composite.
(package private) void	scroll(Event e)
void	setEditor(Control editor) Specify the Control that is to be displayed.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

horizontalAlignment

public int horizontalAlignment

Specifies how the editor should be aligned relative to the control. Allowed values are SWT.LEFT, SWT.RIGHT and SWT.CENTER. The default value is SWT.CENTER.

grabHorizontal

public boolean grabHorizontal

Specifies whether the editor should be sized to use the entire width of the control. True means resize the editor to the same width as the cell. False means do not adjust the width of the editor. The default value is false.

minimumWidth

public int minimumWidth

Specifies the minimum width the editor can have. This is used in association with a true value of grabHorizontal. If the cell becomes smaller than the minimumWidth, the editor will not made smaller than the minimum width value. The default value is 0.

verticalAlignment

public int verticalAlignment

Specifies how the editor should be aligned relative to the control. Allowed values are SWT.TOP, SWT.BOTTOM and SWT.CENTER. The default value is SWT.CENTER.

grabVertical

public boolean grabVertical

Specifies whether the editor should be sized to use the entire height of the control. True means resize the editor to the same height as the underlying control. False means do not adjust the height of the editor. The default value is false.

minimumHeight

public int minimumHeight

Specifies the minimum height the editor can have. This is used in association with a true value of grabVertical. If the control becomes smaller than the minimumHeight, the editor will not made smaller than the minimum height value. The default value is 0.

parent

Composite parent

editor

Control editor

hadFocus

private boolean hadFocus

controlListener

private Listener controlListener

scrollbarListener

private Listener scrollbarListener

EVENTS

private static final int[] EVENTS

Constructor Detail

ControlEditor

public ControlEditor(Composite parent)

Creates a ControlEditor for the specified Composite.

Parameters:

parent - the Composite above which this editor will be displayed

Method Detail

computeBounds

Rectangle computeBounds()

dispose

public void dispose()

Removes all associations between the Editor and the underlying composite. The composite and the editor Control are not disposed.

getEditor

public Control getEditor()

Returns the Control that is displayed above the composite being edited.

Returns:

the Control that is displayed above the composite being edited

layout

public void layout()

Lays out the control within the underlying composite. This method should be called after changing one or more fields to force the Editor to resize.

Since:

2.1

scroll

void scroll(Event e)

setEditor

public void setEditor(Control editor)

Specify the Control that is to be displayed.

Note: The Control provided as the editor must be created with its parent being the Composite specified in the ControlEditor constructor.

Parameters:

editor - the Control that is displayed above the composite being edited