/*
* Copyright (c) 2009 Kathryn Huxtable and Kenneth Orr.
*
* This file is part of the SeaGlass Pluggable Look and Feel.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* $Id$
*/
package com.seaglasslookandfeel.component;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GraphicsConfiguration;
import java.awt.Insets;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Toolkit;
import javax.swing.BoxLayout;
import javax.swing.JComboBox;
import javax.swing.ListSelectionModel;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.border.Border;
import javax.swing.border.LineBorder;
import javax.swing.plaf.basic.BasicComboPopup;
/**
* SeaGlassComboPopup. The code to calculate the popup bounds was lifted from
* Quaqua by Werner Randelshofer.
*
* @see javax.swing.plaf.synth.SynthComboPopup
* @see ch.randelshofer.quaqua.QuaquaComboPopup
*/
public class SeaGlassComboPopup extends BasicComboPopup {
private static final long serialVersionUID = -2424496840321170560L;
private static final int LEFT_SHIFT = 5;
private Color BORDER_COLOR = UIManager.getColor("seaGlassPopupBorder");
private Border LIST_BORDER = new LineBorder(BORDER_COLOR, 1);
/**
* Creates a new SeaGlassComboPopup object.
*
* @param combo the combo box.
*/
public SeaGlassComboPopup(JComboBox combo) {
super(combo);
}
/**
* {@inheritDoc}
*/
@Override
public void updateUI() {
// TODO Auto-generated method stub
super.updateUI();
}
/**
* Is the combo box popup a "drop down" popup, or does it overlay the box?
*
* @return {@code true} if the popup should drop down from the combo box,
* {@code false} if it should overlay the combo box.
*/
private boolean isDropDown() {
return comboBox.isEditable() || hasScrollBars();
}
/**
* Does the combo box have scroll bars?
*
* @return {@code true} if the combo box popup has scroll bars,
* {@code false} otherwise.
*/
private boolean hasScrollBars() {
return comboBox.getModel().getSize() > getMaximumRowCount();
}
/**
* Is the combo box editable?
*
* @return {@code true} if the combo box popup is editable, {@code false}
* otherwise.
*/
private boolean isEditable() {
return comboBox.isEditable();
}
/**
* Configures the list which is used to hold the combo box items in the
* popup. This method is called when the UI class is created.
*/
@Override
protected void configureList() {
list.setFont(comboBox.getFont());
list.setBorder(null);
list.setCellRenderer(comboBox.getRenderer());
list.setFocusable(false);
list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
int selectedIndex = comboBox.getSelectedIndex();
if (selectedIndex == -1) {
list.clearSelection();
} else {
list.setSelectedIndex(selectedIndex);
list.ensureIndexIsVisible(selectedIndex);
}
installListListeners();
}
/**
* Configures the popup portion of the combo box. This method is called when
* the UI class is created.
*/
protected void configurePopup() {
setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
setBorderPainted(true);
setBorder(LIST_BORDER);
setOpaque(false);
add(scroller);
setDoubleBuffered(true);
setFocusable(false);
}
/**
* Calculate the placement and size of the popup portion of the combo box
* based on the combo box location and the enclosing screen bounds. If no
* transformations are required, then the returned rectangle will have the
* same values as the parameters.
*
* @param px starting x location
* @param py starting y location
* @param pw starting width
* @param ph starting height
*
* @return a rectangle which represents the placement and size of the popup
*/
protected Rectangle computePopupBounds(int px, int py, int pw, int ph) {
Toolkit toolkit = Toolkit.getDefaultToolkit();
Rectangle screenBounds;
int listWidth = getList().getPreferredSize().width;
Insets margin = comboBox.getInsets();
if (hasScrollBars()) {
px += margin.left;
pw = Math.max(pw - margin.left - margin.right, listWidth + 16);
} else {
px += margin.left;
pw = Math.max(pw - LEFT_SHIFT - margin.left, listWidth);
}
// Calculate the desktop dimensions relative to the combo box.
GraphicsConfiguration gc = comboBox.getGraphicsConfiguration();
Point p = new Point();
SwingUtilities.convertPointFromScreen(p, comboBox);
if (gc == null) {
screenBounds = new Rectangle(p, toolkit.getScreenSize());
} else {
// Get the screen insets.
Insets screenInsets = Toolkit.getDefaultToolkit().getScreenInsets(gc);
screenBounds = new Rectangle(gc.getBounds());
screenBounds.width -= (screenInsets.left + screenInsets.right);
screenBounds.height -= (screenInsets.top + screenInsets.bottom);
screenBounds.x += screenInsets.left;
screenBounds.y += screenInsets.top;
}
if (isDropDown()) {
if (isEditable()) {
py -= margin.bottom + 2;
} else {
py -= margin.bottom;
}
} else {
int yOffset = -margin.top;
int selectedIndex = comboBox.getSelectedIndex();
if (selectedIndex <= 0) {
py = -yOffset;
} else {
py = -yOffset - list.getCellBounds(0, selectedIndex - 1).height;
}
}
// Compute the rectangle for the popup menu
Rectangle rect = new Rectangle(px, Math.max(py, p.y + screenBounds.y), Math.min(screenBounds.width, pw),
Math.min(screenBounds.height - 40, ph));
// Add the preferred scroll bar width, if the popup does not fit
// on the available rectangle.
if (rect.height < ph) {
rect.width += 16;
}
return rect;
}
/**
* Sets the list selection index to the selectedIndex. This method is used
* to synchronize the list selection with the combo box selection.
*
* @param selectedIndex the index to set the list
*/
private void setListSelection(int selectedIndex) {
if (selectedIndex == -1) {
list.clearSelection();
} else {
list.setSelectedIndex(selectedIndex);
list.ensureIndexIsVisible(selectedIndex);
}
}
/**
* Implementation of ComboPopup.show().
*/
public void show() {
setListSelection(comboBox.getSelectedIndex());
Point location = getPopupLocation();
show(comboBox, location.x, location.y);
// For some reason, this is needed to clear the old selection being
// displayed. Calling list.clearSelection() doesn't cut it.
list.repaint();
}
/**
* Get the maximum row count to display. If none is set, return 100.
*
* @return the maximum row count to display.
*/
private int getMaximumRowCount() {
// return isEditable() ? comboBox.getMaximumRowCount() : 100;
return comboBox.getMaximumRowCount();
}
/**
* Calculates the upper left location of the Popup.
*
* @return the Point representing the upper-left coordinate of the Popup.
*/
private Point getPopupLocation() {
Dimension popupSize = comboBox.getSize();
Insets insets = getInsets();
// reduce the width of the scrollpane by the insets so that the popup
// is the same width as the combo box.
popupSize.setSize(popupSize.width - (insets.right + insets.left), getPopupHeightForRowCount(getMaximumRowCount()));
Rectangle popupBounds = computePopupBounds(0, comboBox.getBounds().height, popupSize.width, popupSize.height);
Dimension scrollSize = popupBounds.getSize();
Point popupLocation = popupBounds.getLocation();
scroller.setMaximumSize(scrollSize);
scroller.setPreferredSize(scrollSize);
scroller.setMinimumSize(scrollSize);
list.revalidate();
return popupLocation;
}
}
