/*******************************************************************************
* Copyright (c) 2012 Pivotal Software, Inc.
* 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:
* Pivotal Software, Inc. - initial API and implementation
*******************************************************************************/
package org.springsource.ide.eclipse.commons.ui;
import org.eclipse.swt.SWT;
import org.eclipse.swt.SWTException;
import org.eclipse.swt.events.ControlEvent;
import org.eclipse.swt.events.ControlListener;
import org.eclipse.swt.events.KeyEvent;
import org.eclipse.swt.events.KeyListener;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.events.MouseListener;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.List;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Shell;
import org.springsource.ide.eclipse.commons.core.Entry;
/**
* A PopupList is a list of selectable items that appears in its own shell
* positioned above its parent shell. It is used for selecting items when
* editing a Table cell (similar to the list that appears when you open a Combo
* box). The list will be positioned so that it does not run off the screen and
* the largest number of items are visible. It may appear above the current
* cursor location or below it depending how close you are to the edge of the
* screen.
* @author Christian Dupuis
* @author Andy Clement
* @author Kris De Volder
* @see <a href="http://www.eclipse.org/swt/">Sample code and further
* information</a>
*/
public class CommandHistoryPopupList {
public static class LabelProvider {
public String getLabel(Entry entry) {
return entry.getMenuLabel();
}
}
public static LabelProvider defaultLabelProvider = new LabelProvider();
private static int checkStyle(int style) {
int mask = SWT.LEFT_TO_RIGHT | SWT.RIGHT_TO_LEFT;
return style & mask;
}
private final Shell shell;
private final List list;
private Entry[] entries;
private int minimumWidth;
private boolean isAbove = true;
private LabelProvider labelProvider = defaultLabelProvider;
/**
* Creates a PopupList above the specified shell.
*
* @param parent a Shell control which will be the parent of the new
* instance (cannot be null)
*/
public CommandHistoryPopupList(Shell parent) {
this(parent, 0);
}
/**
* Creates a PopupList above the specified shell.
*
* @param parent a widget which will be the parent of the new instance
* (cannot be null)
* @param style the style of widget to construct
*
* @since 3.0
*/
public CommandHistoryPopupList(Shell parent, int style) {
shell = new Shell(parent, checkStyle(style));
list = new List(shell, SWT.SINGLE | SWT.V_SCROLL);
// close dialog if user selects outside of the shell
shell.addListener(SWT.Deactivate, new Listener() {
public void handleEvent(Event e) {
shell.setVisible(false);
}
});
// resize shell when list resizes
shell.addControlListener(new ControlListener() {
public void controlMoved(ControlEvent e) {
}
public void controlResized(ControlEvent e) {
Rectangle shellSize = shell.getClientArea();
list.setSize(shellSize.width, shellSize.height);
}
});
// return list selection on Mouse Up or Carriage Return
list.addMouseListener(new MouseListener() {
public void mouseDoubleClick(MouseEvent e) {
}
public void mouseDown(MouseEvent e) {
}
public void mouseUp(MouseEvent e) {
shell.setVisible(false);
}
});
list.addKeyListener(new KeyListener() {
public void keyPressed(KeyEvent e) {
if (e.character == '\r') {
shell.setVisible(false);
}
}
public void keyReleased(KeyEvent e) {
}
});
}
/**
* Gets the widget font.
* <p>
* @return the widget font
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> <li>
* ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created
* the receiver</li>
* </ul>
*/
public Font getFont() {
return list.getFont();
}
/**
* Gets the items.
* <p>
* This operation will fail if the items cannot be queried from the OS.
*
* @return the items in the widget
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> <li>
* ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created
* the receiver</li>
* </ul>
*/
public Entry[] getItems() {
return entries;
}
private String getLabel(Entry entry) {
return labelProvider.getLabel(entry);
}
/**
* Gets the minimum width of the list.
*
* @return the minimum width of the list
*/
public int getMinimumWidth() {
return minimumWidth;
}
/**
* Launches the Popup List, waits for an item to be selected and then closes
* the PopupList.
*
* @param rect the initial size and location of the PopupList; the dialog
* will be positioned so that it does not run off the screen and the largest
* number of items are visible
*
* @return the text of the selected item or null if no item is selected
*/
public Entry open(Rectangle rect) {
Point listSize = list.computeSize(rect.width, SWT.DEFAULT, false);
Rectangle screenSize = shell.getDisplay().getBounds();
// Position the dialog so that it does not run off the screen and the
// largest number of items are visible
int spaceBelow = spaceBelow(rect, screenSize) - 30;
int spaceAbove = spaceAbove(rect, screenSize) - 30;
int y = 0;
if (listSize.y <= spaceAbove) {
// place popup list above table cell
setAbove(true);
if (listSize.y > spaceAbove) {
listSize.y = spaceAbove;
}
else {
listSize.y += 2;
}
y = rect.y - listSize.y;
}
else {
// place popup list below table cell
setAbove(false);
if (listSize.y > spaceBelow) {
listSize.y = spaceBelow;
}
else {
listSize.y += 2;
}
y = rect.y + rect.height;
}
// Make dialog as wide as the cell
listSize.x = rect.width;
// dialog width should not be less than minimumWidth
if (listSize.x < minimumWidth) {
listSize.x = minimumWidth;
}
// Align right side of dialog with right side of cell
int x = rect.x + rect.width - listSize.x;
shell.setBounds(x, y, listSize.x, listSize.y);
shell.open();
list.setFocus();
Display display = shell.getDisplay();
while (!shell.isDisposed() && shell.isVisible()) {
if (!display.readAndDispatch()) {
display.sleep();
}
}
Entry result = null;
if (!shell.isDisposed()) {
int selected = list.getSelectionIndex();
shell.dispose();
if (selected >= 0) {
result = entries[isAbove ? entries.length - selected - 1 : selected];
}
}
return result;
}
/**
* Selects an item with text that starts with specified String.
* <p>
* If the item is not currently selected, it is selected. If the item at an
* index is selected, it remains selected. If the string is not matched, it
* is ignored.
*
* @param string the text of the item
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> <li>
* ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created
* the receiver</li>
* </ul>
*/
public void select(String string) {
String[] items = list.getItems();
// find the first entry in the list that starts with the
// specified string
if (string != null) {
for (String item : items) {
if (item.startsWith(string)) {
int index = list.indexOf(item);
list.select(index);
break;
}
}
}
}
private void setAbove(boolean b) {
if (isAbove != b) {
isAbove = b;
setItems(entries);
}
}
/**
* Sets the widget font.
* <p>
* When new font is null, the font reverts to the default system font for
* the widget.
*
* @param font the new font (or null)
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> <li>
* ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created
* the receiver</li>
* </ul>
*/
public void setFont(Font font) {
list.setFont(font);
}
/**
*
* Sets all items.
* <p>
* The previous selection is cleared. The previous items are deleted. The
* new items are added. The top index is set to 0.
*
* @param strings the array of items
*
* This operation will fail when an item is null or could not be added in
* the OS.
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the items array is null</li> <li>
* ERROR_INVALID_ARGUMENT - if an item in the items array is null</li>
* </ul>
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> <li>
* ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created
* the receiver</li>
* </ul>
*/
public void setItems(Entry[] entries) {
this.entries = entries;
String[] strings = new String[entries.length];
for (int i = 0; i < strings.length; i++) {
strings[isAbove ? strings.length - i - 1 : i] = getLabel(entries[i]);
}
list.setItems(strings);
list.select(isAbove ? strings.length - 1 : 0);
}
public void setLabelProvider(LabelProvider labelProvider) {
this.labelProvider = labelProvider;
}
/**
* Sets the minimum width of the list.
*
* @param width the minimum width of the list
*/
public void setMinimumWidth(int width) {
if (width < 0) {
SWT.error(SWT.ERROR_INVALID_ARGUMENT);
}
minimumWidth = width;
}
private int spaceAbove(Rectangle rect, Rectangle screenSize) {
int screenTop = screenSize.y;
int rectTop = rect.y;
return rectTop - screenTop;
}
private int spaceBelow(Rectangle rect, Rectangle screenSize) {
int screenBottom = screenSize.y + screenSize.height;
int rectBottom = rect.y + rect.height;
return screenBottom - rectBottom;
}
}