From 0daa4359bdaba6372bc8235550892afdef003120 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Tomi=20Korpip=C3=A4=C3=A4?= Date: Tue, 8 Oct 2013 10:12:57 +0300 Subject: Bars example documented Change-Id: Iac5fcb0cf1c822b09dbbe2c33f157d8b78b6bb75 Reviewed-by: Miikka Heikkinen --- examples/bars/doc/images/bars-example-2.png | Bin 0 -> 198263 bytes examples/bars/doc/images/bars-example.png | Bin 163146 -> 135559 bytes examples/bars/doc/src/bars.qdoc | 156 +++++++++++++++++++++++++++- examples/bars/main.cpp | 73 +++++++++---- 4 files changed, 206 insertions(+), 23 deletions(-) create mode 100644 examples/bars/doc/images/bars-example-2.png (limited to 'examples') diff --git a/examples/bars/doc/images/bars-example-2.png b/examples/bars/doc/images/bars-example-2.png new file mode 100644 index 00000000..2083a8e0 Binary files /dev/null and b/examples/bars/doc/images/bars-example-2.png differ diff --git a/examples/bars/doc/images/bars-example.png b/examples/bars/doc/images/bars-example.png index 0f321c95..a87f4bdf 100644 Binary files a/examples/bars/doc/images/bars-example.png and b/examples/bars/doc/images/bars-example.png differ diff --git a/examples/bars/doc/src/bars.qdoc b/examples/bars/doc/src/bars.qdoc index 1db72e47..a8de709b 100644 --- a/examples/bars/doc/src/bars.qdoc +++ b/examples/bars/doc/src/bars.qdoc @@ -22,9 +22,161 @@ \ingroup qtdatavisualization_examples \brief Using an item model as data source for Q3DBars. - The bars example shows how to make a simple 3D bar graph using Q3DBars. + The bars example shows how to make a simple 3D bar graph using Q3DBars and how to modify the + data being drawn at run-time. The example shows how to: + + \list + \li How to create an application with Q3DBars and widgets + \li How to use QItemModelBarDataMapping and QItemModelBarDataProxy to set data to the graph + \li How to use a table widget to modify the data in the graph + \endlist + + \image bars-example-2.png + + \section1 Creating the application + + First, in main.cpp, we create a QApplication, instantiate Q3DBars and a window container for it: + + \snippet ../examples/bars/main.cpp 0 + + The call to QWidget::createWindowContainer is required, as all data visualization types + (Q3DBars, Q3DScatter, Q3DSurface) inherit QWindow. Any class inheriting QWindow cannot be used + as a widget any other way. + + Then we'll create a layout and add the graph and the table widget into it: + + \snippet ../examples/bars/main.cpp 1 + + The table widget is going to be used to display the numerical data being inserted into the + graph, and to modify it (See \l {Adding data to the graph} and \l {Interacting with the data}). + + We need to instantiate QItemModelBarDataMapping and QItemModelBarDataProxy and give them to the + graph: + + \snippet ../examples/bars/main.cpp 2 + + Here we tell the mapping object to directly map model's rows and columns into proxy's rows and + columns instead of defining row and column roles to map for them. Then we give the model from + the table widget and the mapping object to the proxy. Finally we set the proxy as the active + data proxy for the graph. + + Next, let's create another class to handle the data addition and other interaction with the + graph. Let's call it GraphDataGenerator (See \l {Setting up the graph} and + \l {Adding data to the graph} for details) and connect some signals between Q3DBars, + GraphDataGenerator and QTableWidget (See \l {Interacting with the data} for a closer look): + + \snippet ../examples/bars/main.cpp 3 + + The application main is done and we can show the graph and start the event loop: + + \snippet ../examples/bars/main.cpp 4 + + \section1 Setting up the graph + + Let's set up the visual attributes for the graph in the constructor of GraphDataGenerator: + + \snippet ../examples/bars/main.cpp 5 + \snippet ../examples/bars/main.cpp 6 + \snippet ../examples/bars/main.cpp 7 + + First we set bar thickness ratio to 1.0, which means bars will be as wide as they are deep. 1.0 + is also the default value, so the line is basically unnecessary. It's left there so you could + easily try how changing it affects the graph. The second line sets bar spacings to 0.2, which + means there will be a gap of 20% of the bar's thickness between the bars in both directions. + + Then, we set the bar type to flat pyramids, overriding the default bar type. + We want to be able to select rows of data for a closer inspection, so we set the selection mode + to slice row. This means that whenever we select a bar in the graph, the whole row will be + displayed separately. + + Next line sets the font to \c Impact. If your system doesn't have it, it will be replaced by + system default. + + And finally, we set theme to \c Digia and camera position to \c {Preset Front}. Now the initial + graph settings are done. + + \note You do not need to set any of these in case you're happy with the defaults. You can + easily try them by commenting out the contents of the constructor. + + \section1 Adding data to the graph + + We created the data generator in the application main and gave it the graph and the table + widget as parameters: + + \code GraphDataGenerator generator(graph, tableWidget); \endcode + + We added a separate start method to the generator, so that it wouldn't start doing anything + until everything else is set up. We then called the method when starting the application: + + \code generator.start(); \endcode + + Let's have a look at the contents of the \c start() method: + + \snippet ../examples/bars/main.cpp 8 + + The main thing \c start() does is set up the data model. It also activates a timer for getting + the accurate dimensions of the table widget after it's been filled with data. The reason we + do this is that the widget doesn't know its final visual domensions until all the data has been + inserted to it and it has been shown. The whole data timer implementation is not vital for the + application, so we won't take a closer look at it. It's just there to make the table look better. + + In \c setupModel() we first introduce the row and column labels, and the actual data: + + \snippet ../examples/bars/main.cpp 9 + + Then we set up the axes: + + \snippet ../examples/bars/main.cpp 10 + + The other lines there are pretty self-explanatory except for the one with the segment count. + We're setting it to five as we want the value axis (the Y-axis) to show more values than just + the lowest and the highest. + + Next we will set up the table widget: + + \snippet ../examples/bars/main.cpp 11 + + After that all that's left is adding the data to the table widget: + + \snippet ../examples/bars/main.cpp 12 + + Now we have a bar graph and a table widget, both displaying the same data. + + You're probably wondering how the data can be displayed in the graph, as the only thing we did + was add it to the table widget? That's because of what we did earlier, in the application main: + + \snippet ../examples/bars/main.cpp 2 + + We created QItemModelBarDataMapping and QItemModelBarDataProxy instances, and gave the proxy + the model of the table widget and the model mapping we just created. Then we set the proxy as + the active proxy for the graph. The proxy maps the rows and the columns in the model of the table + widget into rows and columns for itself using the model mapping, and the graph gets the data + to be displayed from its active proxy. + + \section1 Interacting with the data + + We made a couple of signal connections in the application main earlier: + + \snippet ../examples/bars/main.cpp 3 + + Now we'll find out what these were for. + + The first one connects a signal from Q3DBars to the GraphDataGenerator. Signal + Q3DBars::selectedBarPosChanged() is emitted when a bar is selected from the graph. We connect + that to a method in the data generator that selects the same data item in the table widget: + + \snippet ../examples/bars/main.cpp 13 + + The second connection does the opposite; it connects a signal from the table widget to a + method in the data generator. The method then selects the corresponding bar in the graph: + + \snippet ../examples/bars/main.cpp 14 + + You can even select an item in the widget and change the value of it, and the new value is + updated to the graph. This is handled again by the active proxy with mapping between the data + in the table widget and itself. \image bars-example.png - TODO + \section1 Example contents */ diff --git a/examples/bars/main.cpp b/examples/bars/main.cpp index 861f1a58..e3ec17c5 100644 --- a/examples/bars/main.cpp +++ b/examples/bars/main.cpp @@ -71,14 +71,17 @@ GraphDataGenerator::GraphDataGenerator(Q3DBars *bargraph, QTableWidget *tableWid m_rowCount(50), m_tableWidget(tableWidget) { + //! [5] // Set up bar specifications; make the bars as wide as they are deep, - // and add a small space between the bars + // and add a small space between them m_graph->setBarThickness(1.0); m_graph->setBarSpacing(QSizeF(0.2, 0.2)); // Set bar type to flat pyramids m_graph->setBarType(QDataVis::MeshStylePyramids, false); + //! [5] + #ifndef USE_STATIC_DATA // Set up sample space; make it as deep as it's wide m_graph->setDataWindow(m_rowCount, m_columnCount); @@ -93,16 +96,25 @@ GraphDataGenerator::GraphDataGenerator(Q3DBars *bargraph, QTableWidget *tableWid m_graph->activeDataProxy()->setItemLabelFormat(QStringLiteral("@valueLabel")); #else - // Set selection mode to zoom row + //! [6] + + // Set selection mode to slice row m_graph->setSelectionMode(QDataVis::SelectionModeSliceRow); + + // Set font m_graph->setFont(QFont("Impact", 20)); + + //! [6] #endif + //! [7] + // Set theme m_graph->setTheme(QDataVis::ThemeDigia); // Set preset camera position m_graph->setCameraPreset(QDataVis::CameraPresetFront); + //! [7] } GraphDataGenerator::~GraphDataGenerator() @@ -123,6 +135,7 @@ void GraphDataGenerator::start() m_dataTimer->start(0); m_tableWidget->setFixedWidth(m_graph->width()); #else + //! [8] setupModel(); // Table needs to be shown before the size of its headers can be accurately obtained, // so we postpone it a bit @@ -130,11 +143,13 @@ void GraphDataGenerator::start() m_dataTimer->setSingleShot(true); QObject::connect(m_dataTimer, &QTimer::timeout, this, &GraphDataGenerator::fixTableSize); m_dataTimer->start(0); + //! [8] #endif } void GraphDataGenerator::setupModel() { + //! [9] // Set up row and column names QStringList days; days << "Monday" << "Tuesday" << "Wednesday" << "Thursday" << "Friday" << "Saturday" << "Sunday"; @@ -142,19 +157,23 @@ void GraphDataGenerator::setupModel() weeks << "week 1" << "week 2" << "week 3" << "week 4" << "week 5"; // Set up data Mon Tue Wed Thu Fri Sat Sun - float hours[5][7] = {{2.0f, 1.0f, 3.0f, 0.2f, 1.0f, 5.0f, 10.0f}, // week 1 - {0.5f, 1.0f, 3.0f, 1.0f, 2.0f, 2.0f, 3.0f}, // week 2 - {1.0f, 1.0f, 2.0f, 1.0f, 4.0f, 4.0f, 4.0f}, // week 3 - {0.0f, 1.0f, 0.0f, 0.0f, 2.0f, 2.0f, 0.3f}, // week 4 - {3.0f, 3.0f, 6.0f, 2.0f, 2.0f, 1.0f, 1.0f}}; // week 5 + float hours[5][7] = {{2.0, 1.0, 3.0, 0.2, 1.0, 5.0, 10.0}, // week 1 + {0.5, 1.0, 3.0, 1.0, 2.0, 2.0, 3.0}, // week 2 + {1.0, 1.0, 2.0, 1.0, 4.0, 4.0, 4.0}, // week 3 + {0.0, 1.0, 0.0, 0.0, 2.0, 2.0, 0.3}, // week 4 + {3.0, 3.0, 6.0, 2.0, 2.0, 1.0, 1.0}}; // week 5 + //! [9] // Add labels + //! [10] m_graph->rowAxis()->setTitle("Week of year"); m_graph->columnAxis()->setTitle("Day of week"); m_graph->valueAxis()->setTitle("Hours spent on the Internet"); m_graph->valueAxis()->setSegmentCount(5); m_graph->valueAxis()->setLabelFormat("%.1f h"); + //! [10] + //! [11] m_tableWidget->setRowCount(5); m_tableWidget->setColumnCount(7); m_tableWidget->setHorizontalHeaderLabels(days); @@ -162,13 +181,16 @@ void GraphDataGenerator::setupModel() m_tableWidget->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff); m_tableWidget->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff); m_tableWidget->setCurrentCell(-1, -1); + //! [11] + //! [12] for (int week = 0; week < weeks.size(); week++) { for (int day = 0; day < days.size(); day++) { QModelIndex index = m_tableWidget->model()->index(week, day); m_tableWidget->model()->setData(index, hours[week][day]); } } + //! [12] } void GraphDataGenerator::addRow() @@ -184,12 +206,15 @@ void GraphDataGenerator::addRow() m_tableWidget->resizeColumnsToContents(); } +//! [13] void GraphDataGenerator::selectFromTable(const QPoint &selection) { m_tableWidget->setFocus(); m_tableWidget->setCurrentCell(selection.x(), selection.y()); } +//! [13] +//! [14] void GraphDataGenerator::selectedFromTable(int currentRow, int currentColumn, int previousRow, int previousColumn) { @@ -197,6 +222,7 @@ void GraphDataGenerator::selectedFromTable(int currentRow, int currentColumn, Q_UNUSED(previousColumn) m_graph->setSelectedBarPos(QPoint(currentRow, currentColumn)); } +//! [14] void GraphDataGenerator::fixTableSize() { @@ -210,45 +236,50 @@ void GraphDataGenerator::fixTableSize() int main(int argc, char **argv) { + //! [0] QApplication app(argc, argv); - - QWidget widget; - QVBoxLayout *layout = new QVBoxLayout(&widget); - Q3DBars *graph = new Q3DBars(); - QSize screenSize = graph->screen()->size(); - QWidget *container = QWidget::createWindowContainer(graph); + //! [0] + + QSize screenSize = graph->screen()->size(); container->setMinimumSize(QSize(screenSize.width() / 2, screenSize.height() / 2)); container->setMaximumSize(screenSize); container->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding); container->setFocusPolicy(Qt::StrongFocus); - widget.setWindowTitle(QStringLiteral("Hours spent on the Internet")); - + //! [1] + QWidget widget; + QVBoxLayout *layout = new QVBoxLayout(&widget); QTableWidget *tableWidget = new QTableWidget(&widget); - tableWidget->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Fixed); - tableWidget->setAlternatingRowColors(true); - layout->addWidget(container, 1); layout->addWidget(tableWidget, 1, Qt::AlignHCenter); + //! [1] + tableWidget->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Fixed); + tableWidget->setAlternatingRowColors(true); + widget.setWindowTitle(QStringLiteral("Hours spent on the Internet")); + + //! [2] // Since we are dealing with QTableWidget, the model will already have data sorted properly - // in rows and columns, so create a custom mapping to utilize this. + // in rows and columns, so create a mapping to utilize this. QItemModelBarDataMapping *mapping = new QItemModelBarDataMapping; mapping->setUseModelCategories(true); QItemModelBarDataProxy *proxy = new QItemModelBarDataProxy(tableWidget->model(), mapping); graph->setActiveDataProxy(proxy); + //! [2] + //! [3] GraphDataGenerator generator(graph, tableWidget); - QObject::connect(graph, &Q3DBars::selectedBarPosChanged, &generator, &GraphDataGenerator::selectFromTable); QObject::connect(tableWidget, &QTableWidget::currentCellChanged, &generator, &GraphDataGenerator::selectedFromTable); + //! [3] + //! [4] widget.show(); generator.start(); - return app.exec(); + //! [4] } -- cgit v1.2.3