qt_demoe/third/qcustomplotdemo/frmexample2/frminteraction.cpp

#include "frminteraction.h"
#include "ui_frminteraction.h"
#include "qmenu.h"
#include "qdebug.h"

frmInterAction::frmInterAction(QWidget *parent) : QWidget(parent), ui(new Ui::frmInterAction)
{
    ui->setupUi(this);
    this->initForm();
}

frmInterAction::~frmInterAction()
{
    delete ui;
}

void frmInterAction::initForm()
{
    std::srand(QDateTime::currentDateTime().toMSecsSinceEpoch() / 1000.0);

    ui->customPlot->setInteractions(QCP::iRangeDrag | QCP::iRangeZoom | QCP::iSelectAxes | QCP::iSelectLegend | QCP::iSelectPlottables);
    ui->customPlot->xAxis->setRange(-8, 8);
    ui->customPlot->yAxis->setRange(-5, 5);
    ui->customPlot->axisRect()->setupFullAxesBox();

    ui->customPlot->plotLayout()->insertRow(0);
    QCPTextElement *title = new QCPTextElement(ui->customPlot, "Interaction Example", QFont("sans", 17, QFont::Bold));
    ui->customPlot->plotLayout()->addElement(0, 0, title);

    ui->customPlot->xAxis->setLabel("x Axis");
    ui->customPlot->yAxis->setLabel("y Axis");
    ui->customPlot->legend->setVisible(true);
    QFont legendFont = font();
    legendFont.setPointSize(10);
    ui->customPlot->legend->setFont(legendFont);
    ui->customPlot->legend->setSelectedFont(legendFont);
    //ui->customPlot->legend->setSelectableParts(QCPLegend::spItems); // legend box shall not be selectable, only legend items

    addRandomGraph();
    addRandomGraph();
    addRandomGraph();
    addRandomGraph();
    ui->customPlot->rescaleAxes();

    //  // connect slot that ties some axis selections together (especially opposite axes):
    connect(ui->customPlot, SIGNAL(selectionChangedByUser()), this, SLOT(selectionChanged()));
    //  // connect slots that takes care that when an axis is selected, only that direction can be dragged and zoomed:
    connect(ui->customPlot, SIGNAL(mousePress(QMouseEvent *)), this, SLOT(mousePress()));
    connect(ui->customPlot, SIGNAL(mouseWheel(QWheelEvent *)), this, SLOT(mouseWheel()));

    // make bottom and left axes transfer their ranges to top and right axes:
    connect(ui->customPlot->xAxis, SIGNAL(rangeChanged(QCPRange)), ui->customPlot->xAxis2, SLOT(setRange(QCPRange)));
    connect(ui->customPlot->yAxis, SIGNAL(rangeChanged(QCPRange)), ui->customPlot->yAxis2, SLOT(setRange(QCPRange)));

    // connect some interaction slots:
    connect(ui->customPlot, SIGNAL(axisDoubleClick(QCPAxis *, QCPAxis::SelectablePart, QMouseEvent *)), this, SLOT(axisLabelDoubleClick(QCPAxis *, QCPAxis::SelectablePart)));
    connect(ui->customPlot, SIGNAL(legendDoubleClick(QCPLegend *, QCPAbstractLegendItem *, QMouseEvent *)), this, SLOT(legendDoubleClick(QCPLegend *, QCPAbstractLegendItem *)));
    connect(title, SIGNAL(doubleClicked(QMouseEvent *)), this, SLOT(titleDoubleClick(QMouseEvent *)));

    // connect slot that shows a message in the status bar when a graph is clicked:
    connect(ui->customPlot, SIGNAL(plottableClick(QCPAbstractPlottable *, int, QMouseEvent *)), this, SLOT(graphClicked(QCPAbstractPlottable *, int)));

    // setup policy and connect slot for context menu popup:
    ui->customPlot->setContextMenuPolicy(Qt::CustomContextMenu);
    connect(ui->customPlot, SIGNAL(customContextMenuRequested(QPoint)), this, SLOT(contextMenuRequest(QPoint)));
}

void frmInterAction::titleDoubleClick(QMouseEvent *event)
{
    Q_UNUSED(event)
    if (QCPTextElement *title = qobject_cast<QCPTextElement *>(sender())) {
        // Set the plot title by double clicking on it
        bool ok;
        QString newTitle = QInputDialog::getText(this, "QCustomPlot example", "New plot title:", QLineEdit::Normal, title->text(), &ok);
        if (ok) {
            title->setText(newTitle);
            ui->customPlot->replot();
        }
    }
}

void frmInterAction::axisLabelDoubleClick(QCPAxis *axis, QCPAxis::SelectablePart part)
{
    // Set an axis label by double clicking on it
    if (part == QCPAxis::spAxisLabel) { // only react when the actual axis label is clicked, not tick label or axis backbone
        bool ok;
        QString newLabel = QInputDialog::getText(this, "QCustomPlot example", "New axis label:", QLineEdit::Normal, axis->label(), &ok);
        if (ok) {
            axis->setLabel(newLabel);
            ui->customPlot->replot();
        }
    }
}

void frmInterAction::legendDoubleClick(QCPLegend *legend, QCPAbstractLegendItem *item)
{
    // Rename a graph by double clicking on its legend item
    Q_UNUSED(legend)
    if (item) { // only react if item was clicked (user could have clicked on border padding of legend where there is no item, then item is 0)
        QCPPlottableLegendItem *plItem = qobject_cast<QCPPlottableLegendItem *>(item);
        bool ok;
        QString newName = QInputDialog::getText(this, "QCustomPlot example", "New graph name:", QLineEdit::Normal, plItem->plottable()->name(), &ok);
        if (ok) {
            plItem->plottable()->setName(newName);
            ui->customPlot->replot();
        }
    }
}

void frmInterAction::selectionChanged()
{
    /*
     normally, axis base line, axis tick labels and axis labels are selectable separately, but we want
     the user only to be able to select the axis as a whole, so we tie the selected states of the tick labels
     and the axis base line together. However, the axis label shall be selectable individually.

     The selection state of the left and right axes shall be synchronized as well as the state of the
     bottom and top axes.

     Further, we want to synchronize the selection of the graphs with the selection state of the respective
     legend item belonging to that graph. So the user can select a graph by either clicking on the graph itself
     or on its legend item.
    */

    // make top and bottom axes be selected synchronously, and handle axis and tick labels as one selectable object:
    if (ui->customPlot->xAxis->selectedParts().testFlag(QCPAxis::spAxis) || ui->customPlot->xAxis->selectedParts().testFlag(QCPAxis::spTickLabels) ||
        ui->customPlot->xAxis2->selectedParts().testFlag(QCPAxis::spAxis) || ui->customPlot->xAxis2->selectedParts().testFlag(QCPAxis::spTickLabels)) {
        ui->customPlot->xAxis2->setSelectedParts(QCPAxis::spAxis | QCPAxis::spTickLabels);
        ui->customPlot->xAxis->setSelectedParts(QCPAxis::spAxis | QCPAxis::spTickLabels);
    }
    // make left and right axes be selected synchronously, and handle axis and tick labels as one selectable object:
    if (ui->customPlot->yAxis->selectedParts().testFlag(QCPAxis::spAxis) || ui->customPlot->yAxis->selectedParts().testFlag(QCPAxis::spTickLabels) ||
        ui->customPlot->yAxis2->selectedParts().testFlag(QCPAxis::spAxis) || ui->customPlot->yAxis2->selectedParts().testFlag(QCPAxis::spTickLabels)) {
        ui->customPlot->yAxis2->setSelectedParts(QCPAxis::spAxis | QCPAxis::spTickLabels);
        ui->customPlot->yAxis->setSelectedParts(QCPAxis::spAxis | QCPAxis::spTickLabels);
    }

    // synchronize selection of graphs with selection of corresponding legend items:
    for (int i = 0; i < ui->customPlot->graphCount(); ++i) {
        QCPGraph *graph = ui->customPlot->graph(i);
        QCPPlottableLegendItem *item = ui->customPlot->legend->itemWithPlottable(graph);
        if (item->selected() || graph->selected()) {
            item->setSelected(true);
            graph->setSelection(QCPDataSelection(graph->data()->dataRange()));
        }
    }
}

void frmInterAction::mousePress()
{
    // if an axis is selected, only allow the direction of that axis to be dragged
    // if no axis is selected, both directions may be dragged

    if (ui->customPlot->xAxis->selectedParts().testFlag(QCPAxis::spAxis)) {
        ui->customPlot->axisRect()->setRangeDrag(ui->customPlot->xAxis->orientation());
    } else if (ui->customPlot->yAxis->selectedParts().testFlag(QCPAxis::spAxis)) {
        ui->customPlot->axisRect()->setRangeDrag(ui->customPlot->yAxis->orientation());
    } else {
        ui->customPlot->axisRect()->setRangeDrag(Qt::Horizontal | Qt::Vertical);
    }
}

void frmInterAction::mouseWheel()
{
    // if an axis is selected, only allow the direction of that axis to be zoomed
    // if no axis is selected, both directions may be zoomed

    if (ui->customPlot->xAxis->selectedParts().testFlag(QCPAxis::spAxis)) {
        ui->customPlot->axisRect()->setRangeZoom(ui->customPlot->xAxis->orientation());
    } else if (ui->customPlot->yAxis->selectedParts().testFlag(QCPAxis::spAxis)) {
        ui->customPlot->axisRect()->setRangeZoom(ui->customPlot->yAxis->orientation());
    } else {
        ui->customPlot->axisRect()->setRangeZoom(Qt::Horizontal | Qt::Vertical);
    }
}

void frmInterAction::addRandomGraph()
{
    int n = 50; // number of points in graph
    double xScale = (std::rand() / (double)RAND_MAX + 0.5) * 2;
    double yScale = (std::rand() / (double)RAND_MAX + 0.5) * 2;
    double xOffset = (std::rand() / (double)RAND_MAX - 0.5) * 4;
    double yOffset = (std::rand() / (double)RAND_MAX - 0.5) * 10;
    double r1 = (std::rand() / (double)RAND_MAX - 0.5) * 2;
    double r2 = (std::rand() / (double)RAND_MAX - 0.5) * 2;
    double r3 = (std::rand() / (double)RAND_MAX - 0.5) * 2;
    double r4 = (std::rand() / (double)RAND_MAX - 0.5) * 2;
    QVector<double> x(n), y(n);
    for (int i = 0; i < n; i++) {
        x[i] = (i / (double)n - 0.5) * 10.0 * xScale + xOffset;
        y[i] = (qSin(x[i] * r1 * 5) * qSin(qCos(x[i] * r2) * r4 * 3) + r3 * qCos(qSin(x[i]) * r4 * 2)) * yScale + yOffset;
    }

    ui->customPlot->addGraph();
    ui->customPlot->graph()->setName(QString("New graph %1").arg(ui->customPlot->graphCount() - 1));
    ui->customPlot->graph()->setData(x, y);
    ui->customPlot->graph()->setLineStyle((QCPGraph::LineStyle)(std::rand() % 5 + 1));
    if (std::rand() % 100 > 50) {
        ui->customPlot->graph()->setScatterStyle(QCPScatterStyle((QCPScatterStyle::ScatterShape)(std::rand() % 14 + 1)));
    }

    QPen graphPen;
    graphPen.setColor(QColor(std::rand() % 245 + 10, std::rand() % 245 + 10, std::rand() % 245 + 10));
    graphPen.setWidthF(std::rand() / (double)RAND_MAX * 2 + 1);
    ui->customPlot->graph()->setPen(graphPen);
    ui->customPlot->replot();
}

void frmInterAction::removeSelectedGraph()
{
    if (ui->customPlot->selectedGraphs().size() > 0) {
        ui->customPlot->removeGraph(ui->customPlot->selectedGraphs().first());
        ui->customPlot->replot();
    }
}

void frmInterAction::removeAllGraphs()
{
    ui->customPlot->clearGraphs();
    ui->customPlot->replot();
}

void frmInterAction::contextMenuRequest(QPoint pos)
{
    QMenu *menu = new QMenu(this);
    menu->setAttribute(Qt::WA_DeleteOnClose);

    if (ui->customPlot->legend->selectTest(pos, false) >= 0) { // context menu on legend requested
        menu->addAction("Move to top left", this, SLOT(moveLegend()))->setData((int)(Qt::AlignTop | Qt::AlignLeft));
        menu->addAction("Move to top center", this, SLOT(moveLegend()))->setData((int)(Qt::AlignTop | Qt::AlignHCenter));
        menu->addAction("Move to top right", this, SLOT(moveLegend()))->setData((int)(Qt::AlignTop | Qt::AlignRight));
        menu->addAction("Move to bottom right", this, SLOT(moveLegend()))->setData((int)(Qt::AlignBottom | Qt::AlignRight));
        menu->addAction("Move to bottom left", this, SLOT(moveLegend()))->setData((int)(Qt::AlignBottom | Qt::AlignLeft));
    } else { // general context menu on graphs requested
        menu->addAction("Add random graph", this, SLOT(addRandomGraph()));
        if (ui->customPlot->selectedGraphs().size() > 0) {
            menu->addAction("Remove selected graph", this, SLOT(removeSelectedGraph()));
        }
        if (ui->customPlot->graphCount() > 0) {
            menu->addAction("Remove all graphs", this, SLOT(removeAllGraphs()));
        }
    }

    menu->popup(ui->customPlot->mapToGlobal(pos));
}

void frmInterAction::moveLegend()
{
    if (QAction *contextAction = qobject_cast<QAction *>(sender())) { // make sure this slot is really called by a context menu action, so it carries the data we need
        bool ok;
        int dataInt = contextAction->data().toInt(&ok);
        if (ok) {
            ui->customPlot->axisRect()->insetLayout()->setInsetAlignment(0, (Qt::Alignment)dataInt);
            ui->customPlot->replot();
        }
    }
}

void frmInterAction::graphClicked(QCPAbstractPlottable *plottable, int dataIndex)
{
    // since we know we only have QCPGraphs in the plot, we can immediately access interface1D()
    // usually it's better to first check whether interface1D() returns non-zero, and only then use it.
    double dataValue = plottable->interface1D()->dataMainValue(dataIndex);
    QString message = QString("Clicked on graph '%1' at data point #%2 with value %3.").arg(plottable->name()).arg(dataIndex).arg(dataValue);
    //ui->statusBar->showMessage(message, 2500);
}