Code for Star Delegate Example
/****************************************************************************
**
** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved.
**
** This file is part of Qt Jambi.
**
** ** This file may be used under the terms of the GNU General Public
** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
** this file. Please review the following information to ensure GNU
** General Public Licensing requirements will be met:
** http://www.trolltech.com/products/qt/opensource.html
**
** If you are unsure which license is appropriate for your use, please
** review the following information:
** http://www.trolltech.com/products/qt/licensing.html or contact the
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**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
****************************************************************************/
package com.trolltech.examples;
import com.trolltech.qt.gui.*;
import com.trolltech.qt.core.*;
import java.util.*;
@QtJambiExample(name = "Star Delegate")
public class StarDelegate extends QWidget {
private QTableWidget table;
private Object tableContent[][] = {
{ tr("Mass in B-Minor"), tr("Baroque"), tr("JS Bach"),
new StarRating(5) },
{ tr("Sex Bomb"), tr("Pop"), tr("Tom Jones"), new StarRating(2) },
{ tr("Three More Foxes"), tr("jazz"), tr("Maynard Ferguson"),
new StarRating(4) },
{ tr("Barbie Girl"), tr("Pop"), tr("Aqua"), new StarRating(5) }
};
public StarDelegate() {
this(null);
}
public StarDelegate(QWidget parent)
{
super(parent);
createTable();
QGridLayout layout = new QGridLayout();
layout.addWidget(table, 0, 0);
setLayout(layout);
setWindowTitle(tr("Star Delegate"));
setWindowIcon(new QIcon("classpath:com/trolltech/images/qt-logo.png"));
setMinimumSize(550, 200);
}
public void createTable()
{
LinkedList<String> headers = new LinkedList<String>();
table = new QTableWidget(4, 4);
table.setItemDelegate(new Delegate(table));
table.setEditTriggers(QAbstractItemView.EditTrigger.DoubleClicked,
QAbstractItemView.EditTrigger.SelectedClicked);
table.setSelectionBehavior(
QAbstractItemView.SelectionBehavior.SelectRows);
headers.add(tr("Title"));
headers.add(tr("Genre"));
headers.add(tr("Artist"));
headers.add(tr("Rating"));
table.setHorizontalHeaderLabels(headers);
for (int i = 0; i < tableContent.length; i++) {
table.setItem(i, 0,
new QTableWidgetItem((String) tableContent[i][0]));
table.setItem(i, 1,
new QTableWidgetItem((String) tableContent[i][1]));
table.setItem(i, 2,
new QTableWidgetItem((String) tableContent[i][2]));
QTableWidgetItem rRating = new QTableWidgetItem();
rRating.setData(Qt.ItemDataRole.DisplayRole, tableContent[i][3]);
table.setItem(i, 3, rRating);
}
table.resizeColumnsToContents();
}
class Delegate extends QItemDelegate
{
public Delegate(QWidget parent)
{
super(parent);
}
@Override
public void paint(QPainter painter, QStyleOptionViewItem option, QModelIndex index)
{
Object data = index.data();
if (data != null && data instanceof StarRating) {
if (option.state().isSet(QStyle.StateFlag.State_Selected)) {
painter.fillRect(option.rect(), option.palette().highlight());
}
((StarRating) data).paint(painter, option.rect(), option.palette(),
StarRating.ReadOnly);
} else
super.paint(painter, option, index);
}
@Override
public QSize sizeHint(QStyleOptionViewItem option, QModelIndex index)
{
Object data = index.data();
if (data instanceof StarRating)
return ((StarRating) data).sizeHint();
else
return super.sizeHint(option, index);
}
@Override
public QWidget createEditor(QWidget parent, QStyleOptionViewItem item,
QModelIndex index)
{
Object data = index.data();
if (data instanceof StarRating)
return new StarEditor(parent, (StarRating) data);
else
return super.createEditor(parent, item, index);
}
@Override
public void setEditorData(QWidget editor, QModelIndex index)
{
Object data = index.data();
if (data instanceof StarRating)
((StarEditor) editor).setStarRating((StarRating) data);
else
super.setEditorData(editor, index);
}
@Override
public void setModelData(QWidget editor, QAbstractItemModel model,
QModelIndex index)
{
if (index.data() instanceof StarRating)
model.setData(index, ((StarEditor) editor).starRating());
else
super.setModelData(editor, model, index);
}
}
class StarEditor extends QWidget
{
private StarRating starRating;
public StarEditor(QWidget parent, StarRating rating)
{
super(parent);
starRating = rating;
setMouseTracking(true);
setAutoFillBackground(true);
}
@Override
public QSize sizeHint()
{
return starRating.sizeHint();
}
@Override
public void paintEvent(QPaintEvent event)
{
QPainter painter = new QPainter(this);
starRating.paint(painter, rect(), palette(), StarRating.ReadWrite);
}
@Override
public void mouseMoveEvent(QMouseEvent event)
{
int star = starAtPosition(event.x());
if (star != starRating.getRating() && star > 0) {
starRating.setRating(star);
update();
}
}
public int starAtPosition(int x)
{
int star = (x / (starRating.sizeHint().width()
/ starRating.getMaxRating())) + 1;
if (star <= 0 || star > starRating.getMaxRating())
return -1;
return star;
}
public void setStarRating(StarRating rating)
{
starRating = rating;
}
public StarRating starRating()
{
return starRating;
}
}
class StarRating
{
private int starCount, maxCount;
private QPolygonF starPolygon, diamondPolygon;
public static final int ReadOnly = 0, ReadWrite = 1, PaintingFactor = 20;
private void setupPolygons() {
starPolygon = new QPolygonF();
starPolygon.append(new QPointF(1.0, 0.5));
for (int i = 1; i < 5; i++)
starPolygon.append(
new QPointF(0.5 + 0.5 * Math.cos(0.8 * i * Math.PI),
0.5 + 0.5 * Math.sin(0.8 * i * Math.PI)));
diamondPolygon = new QPolygonF();
diamondPolygon.append(new QPointF(0.4, 0.5));
diamondPolygon.append(new QPointF(0.5, 0.4));
diamondPolygon.append(new QPointF(0.6, 0.5));
diamondPolygon.append(new QPointF(0.5, 0.6));
diamondPolygon.append(new QPointF(0.4, 0.5));
}
public StarRating()
{
this(1, 5);
}
public StarRating(int rating)
{
this(rating, 5);
}
public StarRating(int rating, int maxRating)
{
setupPolygons();
maxCount = maxRating;
setRating(rating);
}
public void setRating(int rating)
{
if (rating > 0 && rating <= maxCount)
starCount = rating;
else
starCount = maxCount;
}
public int getRating()
{
return starCount;
}
public int getMaxRating()
{
return maxCount;
}
public void paint(QPainter painter, QRect rect, QPalette palette,
int mode)
{
painter.save();
painter.setRenderHint(QPainter.RenderHint.Antialiasing, true);
painter.setPen(Qt.PenStyle.NoPen);
if (mode == ReadWrite)
painter.setBrush(palette.highlight());
else
painter.setBrush(palette.text());
int yOffset = (rect.height() - PaintingFactor) / 2;
painter.translate(rect.x(), rect.y() + yOffset);
painter.scale(PaintingFactor, PaintingFactor);
for (int i = 0; i < maxCount; i++) {
if (i < starCount)
painter.drawPolygon(starPolygon, Qt.FillRule.WindingFill);
else
painter.drawPolygon(diamondPolygon, Qt.FillRule.WindingFill);
painter.translate(1.0, 0.0);
}
painter.restore();
}
public QSize sizeHint()
{
return new QSize(PaintingFactor * maxCount, PaintingFactor);
}
}
public static void main(String args[])
{
QApplication.initialize(args);
QWidget widget = new StarDelegate();
widget.show();
widget.resize(470, 200);
QApplication.exec();
}
}