[Qt Widgets version] qtdemo/viewportcontroldemo.cpp
#include <QApplication>
#include <QPushButton>
#include <QMouseEvent>
#include <QFileDialog>
#include <math.h>
#include <sstream>
#include <algorithm>
#include "viewportcontroldemo.h"
ViewPortControlDemo::ViewPortControlDemo(QWidget *parent) :
QDialog(parent)
{
//
// Set up the GUI
//
setFixedSize(772, 478);
setWindowTitle("Zooming and Scrolling with Viewport Control");
// The frame on the left side
QFrame *frame = new QFrame(this);
frame->setGeometry(4, 4, 120, 470);
frame->setFrameShape(QFrame::StyledPanel);
// Pointer push button
QPushButton *pointerPB = new QPushButton(QIcon(":/icons/scroll_icon.png"), "Scroll", frame);
pointerPB->setGeometry(4, 8, 112, 28);
pointerPB->setStyleSheet("QPushButton { text-align:left; padding:5px}");
pointerPB->setCheckable(true);
// Zoom In push button
QPushButton *zoomInPB = new QPushButton(QIcon(":/icons/zoomin_icon.png"), "Zoom In", frame);
zoomInPB->setGeometry(4, 36, 112, 28);
zoomInPB->setStyleSheet("QPushButton { text-align:left; padding:5px}");
zoomInPB->setCheckable(true);
// Zoom Out push button
QPushButton *zoomOutPB = new QPushButton(QIcon(":/icons/zoomout_icon.png"), "Zoom Out", frame);
zoomOutPB->setStyleSheet("QPushButton { text-align:left; padding:5px}");
zoomOutPB->setGeometry(4, 64, 112, 28);
zoomOutPB->setCheckable(true);
// Save push button
QPushButton *savePB = new QPushButton(QIcon(":/icons/save_icon.png"), "Save", frame);
savePB->setStyleSheet("QPushButton { text-align:left; padding:5px}");
savePB->setGeometry(4, 120, 112, 28);
connect(savePB, SIGNAL(clicked(bool)), SLOT(onSave(bool)));
// The Pointer/Zoom In/Zoom Out buttons form a button group
mouseUsage = new QButtonGroup(frame);
mouseUsage->addButton(pointerPB, Chart::MouseUsageScroll);
mouseUsage->addButton(zoomInPB, Chart::MouseUsageZoomIn);
mouseUsage->addButton(zoomOutPB, Chart::MouseUsageZoomOut);
connect(mouseUsage, SIGNAL(buttonPressed(QAbstractButton*)),
SLOT(onMouseUsageChanged(QAbstractButton*)));
// Chart Viewer
m_ChartViewer = new QChartViewer(this);
m_ChartViewer->setGeometry(128, 4, 640, 400);
connect(m_ChartViewer, SIGNAL(viewPortChanged()), SLOT(onViewPortChanged()));
connect(m_ChartViewer, SIGNAL(mouseMovePlotArea(QMouseEvent*)),
SLOT(onMouseMovePlotArea(QMouseEvent*)));
m_ViewPortControl = new QViewPortControl(this);
m_ViewPortControl->setGeometry(128, 403, 640, 70);
//
// Initialize the chart
//
// Load the data
loadData();
// Initialize the QChartViewer
initChartViewer(m_ChartViewer);
// Initially set the mouse to drag to scroll mode
pointerPB->click();
// Trigger the ViewPortChanged event to draw the chart
m_ChartViewer->updateViewPort(true, true);
// Draw and display the full chart in the CViewPortControl
drawFullChart(m_ViewPortControl, m_ChartViewer);
// Bind the CChartViewer to the CViewPortControl
m_ViewPortControl->setViewer(m_ChartViewer);
}
ViewPortControlDemo::~ViewPortControlDemo()
{
delete m_ranSeries;
delete m_ChartViewer->getChart();
delete m_ViewPortControl->getChart();
}
//
// Load the data
//
void ViewPortControlDemo::loadData()
{
// In this example, we just use random numbers as data.
m_ranSeries = new RanSeries(127);
m_timeStamps = m_ranSeries->getDateSeries(1827, Chart::chartTime(2010, 1, 1), 86400);
m_dataSeriesA = m_ranSeries->getSeries(1827, 150, -10, 10);
m_dataSeriesB = m_ranSeries->getSeries(1827, 200, -10, 10);
m_dataSeriesC = m_ranSeries->getSeries(1827, 250, -8, 8);
}
//
// Initialize the QChartViewer
//
void ViewPortControlDemo::initChartViewer(QChartViewer *viewer)
{
// Set the full x range to be the duration of the data
viewer->setFullRange("x", m_timeStamps[0], m_timeStamps[m_timeStamps.len - 1]);
// Initialize the view port to show the latest 20% of the time range
viewer->setViewPortWidth(0.2);
viewer->setViewPortLeft(1 - viewer->getViewPortWidth());
// Set the maximum zoom to 10 points
viewer->setZoomInWidthLimit(10.0 / m_timeStamps.len);
viewer->setMouseWheelZoomRatio(1.1);
}
//
// The ViewPortChanged event handler. This event occurs if the user scrolls or zooms in
// or out the chart by dragging or clicking on the chart. It can also be triggered by
// calling WinChartViewer.updateViewPort.
//
void ViewPortControlDemo::onViewPortChanged()
{
// Update chart if necessary
if (m_ChartViewer->needUpdateChart())
drawChart(m_ChartViewer);
}
//
// Draw the chart and display it in the given viewer
//
void ViewPortControlDemo::drawChart(QChartViewer *viewer)
{
// Get the start date and end date that are visible on the chart.
double viewPortStartDate = viewer->getValueAtViewPort("x", viewer->getViewPortLeft());
double viewPortEndDate = viewer->getValueAtViewPort("x", viewer->getViewPortLeft() +
viewer->getViewPortWidth());
// Get the array indexes that corresponds to the visible start and end dates
int startIndex = (int)floor(Chart::bSearch(m_timeStamps, viewPortStartDate));
int endIndex = (int)ceil(Chart::bSearch(m_timeStamps, viewPortEndDate));
int noOfPoints = endIndex - startIndex + 1;
// Extract the part of the data array that are visible.
DoubleArray viewPortTimeStamps = DoubleArray(m_timeStamps.data + startIndex, noOfPoints);
DoubleArray viewPortDataSeriesA = DoubleArray(m_dataSeriesA.data + startIndex, noOfPoints);
DoubleArray viewPortDataSeriesB = DoubleArray(m_dataSeriesB.data + startIndex, noOfPoints);
DoubleArray viewPortDataSeriesC = DoubleArray(m_dataSeriesC.data + startIndex, noOfPoints);
//
// At this stage, we have extracted the visible data. We can use those data to plot the chart.
//
///////////////////////////////////////////////////////////////////////////////////////
// Configure overall chart appearance.
///////////////////////////////////////////////////////////////////////////////////////
// Create an XYChart object of size 640 x 400 pixels
XYChart *c = new XYChart(640, 400);
// Set the plotarea at (55, 55) with width 80 pixels less than chart width, and height 92 pixels
// less than chart height. Use a vertical gradient from light blue (f0f6ff) to sky blue (a0c0ff)
// as background. Set border to transparent and grid lines to white (ffffff).
c->setPlotArea(55, 55, c->getWidth() - 80, c->getHeight() - 92, c->linearGradientColor(0, 55, 0,
c->getHeight() - 35, 0xf0f6ff, 0xa0c0ff), -1, Chart::Transparent, 0xffffff, 0xffffff);
// As the data can lie outside the plotarea in a zoomed chart, we need enable clipping.
c->setClipping();
// Add a title box using dark grey (0x333333) 15pt Arial Bold font
c->addTitle(" Zooming and Scrolling with Viewport Control", "Arial Bold", 15, 0x333333);
// Set legend icon style to use line style icon, sized for 10pt font
c->getLegend()->setLineStyleKey();
c->getLegend()->setFontSize(10);
// Set the x and y axis stems to transparent and the label font to 10pt Arial
c->xAxis()->setColors(Chart::Transparent);
c->yAxis()->setColors(Chart::Transparent);
c->xAxis()->setLabelStyle("Arial", 10);
c->yAxis()->setLabelStyle("Arial", 10);
// Add axis title using 10pt Arial Bold font
c->yAxis()->setTitle("Ionic Temperature (C)", "Arial Bold", 10);
///////////////////////////////////////////////////////////////////////////////////////
// Add data to chart
///////////////////////////////////////////////////////////////////////////////////////
//
// In this example, we represent the data by lines. You may modify the code below to use other
// representations (areas, scatter plot, etc).
//
// Add a line layer for the lines, using a line width of 2 pixels
LineLayer *layer = c->addLineLayer();
layer->setLineWidth(2);
// In this demo, we do not have too many data points. In real code, the chart may contain a lot
// of data points when fully zoomed out - much more than the number of horizontal pixels in this
// plot area. So it is a good idea to use fast line mode.
layer->setFastLineMode();
// Now we add the 3 data series to a line layer, using the color red (0xff3333), green
// (0x008800) and blue (0x3333cc)
layer->setXData(viewPortTimeStamps);
layer->addDataSet(viewPortDataSeriesA, 0xff3333, "Alpha");
layer->addDataSet(viewPortDataSeriesB, 0x008800, "Beta");
layer->addDataSet(viewPortDataSeriesC, 0x3333cc, "Gamma");
///////////////////////////////////////////////////////////////////////////////////////
// Configure axis scale and labelling
///////////////////////////////////////////////////////////////////////////////////////
// Set the x-axis as a date/time axis with the scale according to the view port x range.
viewer->syncDateAxisWithViewPort("x", c->xAxis());
// For the automatic y-axis labels, set the minimum spacing to 30 pixels.
c->yAxis()->setTickDensity(30);
//
// In this demo, the time range can be from a few years to a few days. We demonstrate how to
// set up different date/time format based on the time range.
//
// If all ticks are yearly aligned, then we use "yyyy" as the label format.
c->xAxis()->setFormatCondition("align", 360 * 86400);
c->xAxis()->setLabelFormat("{value|yyyy}");
// If all ticks are monthly aligned, then we use "mmm yyyy" in bold font as the first
// label of a year, and "mmm" for other labels.
c->xAxis()->setFormatCondition("align", 30 * 86400);
c->xAxis()->setMultiFormat(Chart::StartOfYearFilter(), "<*font=bold*>{value|mmm<*br*>yyyy}",
Chart::AllPassFilter(), "{value|mmm}");
// If all ticks are daily algined, then we use "mmm dd<*br*>yyyy" in bold font as the
// first label of a year, and "mmm dd" in bold font as the first label of a month, and
// "dd" for other labels.
c->xAxis()->setFormatCondition("align", 86400);
c->xAxis()->setMultiFormat(Chart::StartOfYearFilter(),
"<*block,halign=left*><*font=bold*>{value|mmm dd<*br*>yyyy}",
Chart::StartOfMonthFilter(), "<*font=bold*>{value|mmm dd}");
c->xAxis()->setMultiFormat(Chart::AllPassFilter(), "{value|dd}");
// For all other cases (sub-daily ticks), use "hh:nn<*br*>mmm dd" for the first label of
// a day, and "hh:nn" for other labels.
c->xAxis()->setFormatCondition("else");
c->xAxis()->setMultiFormat(Chart::StartOfDayFilter(), "<*font=bold*>{value|hh:nn<*br*>mmm dd}",
Chart::AllPassFilter(), "{value|hh:nn}");
///////////////////////////////////////////////////////////////////////////////////////
// Output the chart
///////////////////////////////////////////////////////////////////////////////////////
// We need to update the track line too. If the mouse is moving on the chart (eg. if
// the user drags the mouse on the chart to scroll it), the track line will be updated
// in the MouseMovePlotArea event. Otherwise, we need to update the track line here.
if (!viewer->isInMouseMoveEvent())
{
trackLineLegend(c, (0 == viewer->getChart()) ? c->getPlotArea()->getRightX() :
viewer->getPlotAreaMouseX());
}
delete viewer->getChart();
viewer->setChart(c);
}
void ViewPortControlDemo::drawFullChart(QViewPortControl *vpc, QChartViewer *viewer)
{
// Create an XYChart object of size 640 x 70 pixels
XYChart *c = new XYChart(640, 70);
// Set the plotarea with the same horizontal position as that in the main chart for alignment.
c->setPlotArea(55, 5, c->getWidth() - 80, c->getHeight() - 11, 0xc0d8ff, -1, 0x888888,
Chart::Transparent, 0xffffff);
// Set the x axis stem to transparent and the label font to 10pt Arial
c->xAxis()->setColors(Chart::Transparent);
c->xAxis()->setLabelStyle("Arial", 10);
// Put the x-axis labels inside the plot area by setting a negative label gap. Use
// setLabelAlignment to put the label at the right side of the tick.
c->xAxis()->setLabelGap(-1);
c->xAxis()->setLabelAlignment(1);
// Set the y axis stem and labels to transparent (that is, hide the labels)
c->yAxis()->setColors(Chart::Transparent, Chart::Transparent);
// Add a line layer for the lines with fast line mode enabled
LineLayer *layer = c->addLineLayer();
layer->setFastLineMode();
// Now we add the 3 data series to a line layer, using the color red (0xff3333), green
// (0x008800) and blue (0x3333cc)
layer->setXData(m_timeStamps);
layer->addDataSet(m_dataSeriesA, 0xff3333);
layer->addDataSet(m_dataSeriesB, 0x008800);
layer->addDataSet(m_dataSeriesC, 0x3333cc);
// The x axis scales should reflect the full range of the view port
c->xAxis()->setDateScale(viewer->getValueAtViewPort("x", 0), viewer->getValueAtViewPort("x", 1));
// For the automatic x-axis labels, set the minimum spacing to 75 pixels.
c->xAxis()->setTickDensity(75);
// For the auto-scaled y-axis, as we hide the labels, we can disable axis rounding. This can
// make the axis scale fit the data tighter.
c->yAxis()->setRounding(false, false);
// Output the chart
vpc->setChart(c);
}
//
// The Pointer, Zoom In or Zoom out button is pressed
//
void ViewPortControlDemo::onMouseUsageChanged(QAbstractButton *b)
{
m_ChartViewer->setMouseUsage(mouseUsage->id(b));
}
//
// The Save button is pressed
//
void ViewPortControlDemo::onSave(bool)
{
QString fileName = QFileDialog::getSaveFileName(this, "Save", "chartdirector_demo",
"PNG (*.png);;JPG (*.jpg);;GIF (*.gif);;BMP (*.bmp);;SVG (*.svg);;PDF (*.pdf)");
if (!fileName.isEmpty())
{
// Save the chart
BaseChart *c = m_ChartViewer->getChart();
if (0 != c)
c->makeChart(fileName.toUtf8().constData());
}
}
//
// Draw track cursor when mouse is moving over plotarea
//
void ViewPortControlDemo::onMouseMovePlotArea(QMouseEvent *)
{
trackLineLegend((XYChart *)m_ChartViewer->getChart(), m_ChartViewer->getPlotAreaMouseX());
m_ChartViewer->updateDisplay();
}
//
// Draw track line with data labels
//
void ViewPortControlDemo::trackLineLegend(XYChart *c, int mouseX)
{
// Clear the current dynamic layer and get the DrawArea object to draw on it.
DrawArea *d = c->initDynamicLayer();
// The plot area object
PlotArea *plotArea = c->getPlotArea();
// Get the data x-value that is nearest to the mouse, and find its pixel coordinate.
double xValue = c->getNearestXValue(mouseX);
int xCoor = c->getXCoor(xValue);
// Draw a vertical track line at the x-position
d->vline(plotArea->getTopY(), plotArea->getBottomY(), xCoor, 0xaaaaaa);
// Container to hold the legend entries
std::vector<std::string> legendEntries;
// Iterate through all layers to build the legend array
for (int i = 0; i < c->getLayerCount(); ++i) {
Layer *layer = c->getLayerByZ(i);
// The data array index of the x-value
int xIndex = layer->getXIndexOf(xValue);
// Iterate through all the data sets in the layer
for (int j = 0; j < layer->getDataSetCount(); ++j) {
DataSet *dataSet = layer->getDataSetByZ(j);
// We are only interested in visible data sets with names
const char *dataName = dataSet->getDataName();
int color = dataSet->getDataColor();
if (dataName && *dataName && (color != Chart::Transparent)) {
// Build the legend entry, consist of the legend icon, name and data value.
double dataValue = dataSet->getValue(xIndex);
std::ostringstream legendEntry;
legendEntry << "<*block*>" << dataSet->getLegendIcon() << " " << dataName << ": " <<
((dataValue == Chart::NoValue) ? "N/A" : c->formatValue(dataValue, "{value|P4}"))
<< "<*/*>";
legendEntries.push_back(legendEntry.str());
// Draw a track dot for data points within the plot area
int yCoor = c->getYCoor(dataSet->getPosition(xIndex), dataSet->getUseYAxis());
if ((yCoor >= plotArea->getTopY()) && (yCoor <= plotArea->getBottomY())) {
d->circle(xCoor, yCoor, 5, 5, color, color);
}
}
}
}
// Create the legend by joining the legend entries
std::ostringstream legendText;
legendText << "<*block,maxWidth=" << plotArea->getWidth() << "*><*block*><*font=Arial Bold*>["
<< c->xAxis()->getFormattedLabel(xValue, "mm/dd/yyyy") << "]<*/*>";
for (int i = ((int)legendEntries.size()) - 1; i >= 0; --i)
legendText << " " << legendEntries[i];
// Display the legend on the top of the plot area
TTFText *t = d->text(legendText.str().c_str(), "Arial Bold", 10);
t->draw(plotArea->getLeftX() + 5, plotArea->getTopY() - 3, 0x333333, Chart::BottomLeft);
t->destroy();
}
[QML/Qt Quick version] qmldemo/viewportcontroldemo.qml
import QtQuick
import QtQuick.Window
import QtQuick.Controls
import QtQuick.Dialogs
import advsofteng.com 1.0
Window {
title: "Zooming and Scrolling with Viewport Control"
width: 770
height: 480
visible: true
modality: Qt.ApplicationModal
Pane {
id: leftPane
width: 120
padding: 5
anchors.top: parent.top;
anchors.bottom: parent.bottom;
Column {
Button {
width: 110
contentItem: Row {
padding: 2; leftPadding: 5
Image { source: "icons/scroll_icon.png"; width:16; height:16; }
Text { text: " Pointer"; font.pixelSize: 12; }
}
checked: viewer.mouseUsage == QmlChartViewer.MouseUsageScroll
onClicked: viewer.mouseUsage = QmlChartViewer.MouseUsageScroll
}
Button {
width: 110
contentItem: Row {
padding: 2; leftPadding: 5;
Image { source: "icons/zoomin_icon.png"; width:16; height:16; }
Text { text: " Zoom In"; font.pixelSize: 12; }
}
checked: viewer.mouseUsage == QmlChartViewer.MouseUsageZoomIn
onClicked: viewer.mouseUsage = QmlChartViewer.MouseUsageZoomIn
}
Button {
width: 110
contentItem: Row {
padding: 2; leftPadding: 5
Image { source: "icons/zoomout_icon.png"; width:16; height:16; }
Text { text: " Zoom Out"; font.pixelSize: 12; }
}
checked: viewer.mouseUsage == QmlChartViewer.MouseUsageZoomOut
onClicked: viewer.mouseUsage = QmlChartViewer.MouseUsageZoomOut
}
// Spacer
Item {width: 1; height: 30}
Button {
width: 110
contentItem: Row {
padding: 2; leftPadding: 5
Image { source: "icons/save_icon.png"; width:16; height:16; }
Text { text: " Save"; font.pixelSize: 12; }
}
onClicked: saveImageDialog.open()
}
}
}
FileDialog {
id: saveImageDialog
title: "Save"
currentFile: "chartdirector_demo"
fileMode: FileDialog.SaveFile
nameFilters: ["PNG (*.png);", "JPG (*.jpg)", "GIF (*.gif)", "BMP (*.bmp)", "SVG (*.svg)", "PDF (*.pdf)"]
onAccepted: demo.saveChartImage(viewer, selectedFile)
}
QmlChartViewer
{
x: 140
id: viewer
// set default mouse usage to scroll and mouse wheel to zoom
mouseUsage: QmlChartViewer.MouseUsageScroll
mouseWheelZoomRatio: 1.1
// Update track cursor on mouse move
onMouseMovePlotArea: demo.drawTrackCursor(this, chartMouseX);
// Update chart on viewport change
onViewPortChanged: if (needUpdateChart) demo.drawChart(this);
}
QmlViewPortControl
{
id: vpCtrl;
anchors.top: viewer.bottom
anchors.left: viewer.left
anchors.right: viewer.right
// Bind the viewport control to the viewer
viewer: viewer;
}
// The backend implementation of this demo.
ViewPortControlDemo {
id: demo
}
Component.onCompleted: {
demo.initChartViewer(viewer, vpCtrl);
viewer.updateViewPort(true, true);
}
}
[QML/Qt Quick version] qmldemo/viewportcontroldemo.cpp
#include "viewportcontroldemo.h"
#include <sstream>
#include <math.h>
ViewPortControlDemo::ViewPortControlDemo(QObject *parent) : QObject(parent)
{
m_currentChart = 0;
m_currentVpcChart = 0;
// Load the data
loadData();
}
ViewPortControlDemo::~ViewPortControlDemo()
{
delete m_ranSeries;
delete m_currentChart;
delete m_currentVpcChart;
}
//
// Load the data
//
void ViewPortControlDemo::loadData()
{
// In this example, we just use random numbers as data.
m_ranSeries = new RanSeries(127);
m_timeStamps = m_ranSeries->getDateSeries(1827, Chart::chartTime(2010, 1, 1), 86400);
m_dataSeriesA = m_ranSeries->getSeries(1827, 150, -10, 10);
m_dataSeriesB = m_ranSeries->getSeries(1827, 200, -10, 10);
m_dataSeriesC = m_ranSeries->getSeries(1827, 250, -8, 8);
}
//
// Initialize the QChartViewer
//
void ViewPortControlDemo::initChartViewer(QmlChartViewer *viewer, QmlViewPortControl *vpCtrl)
{
// Set the full x range to be the duration of the data
viewer->setFullRange("x", m_timeStamps[0], m_timeStamps[m_timeStamps.len - 1]);
// Initialize the view port to show the latest 20% of the time range
viewer->setViewPortWidth(0.2);
viewer->setViewPortLeft(1 - viewer->getViewPortWidth());
// Set the maximum zoom to 10 points
viewer->setZoomInWidthLimit(10.0 / m_timeStamps.len);
viewer->setMouseWheelZoomRatio(1.1);
// Trigger the ViewPortChanged event to draw the chart
viewer->updateViewPort(true, true);
// Draw and display the full chart in the CViewPortControl
drawFullChart(vpCtrl);
}
//
// Draw the chart and display it in the given viewer
//
void ViewPortControlDemo::drawChart(QmlChartViewer *viewer)
{
// Get the start date and end date that are visible on the chart.
double viewPortStartDate = viewer->getValueAtViewPort("x", viewer->getViewPortLeft());
double viewPortEndDate = viewer->getValueAtViewPort("x", viewer->getViewPortLeft() +
viewer->getViewPortWidth());
// Get the array indexes that corresponds to the visible start and end dates
int startIndex = (int)floor(Chart::bSearch(m_timeStamps, viewPortStartDate));
int endIndex = (int)ceil(Chart::bSearch(m_timeStamps, viewPortEndDate));
int noOfPoints = endIndex - startIndex + 1;
// Extract the part of the data array that are visible.
DoubleArray viewPortTimeStamps = DoubleArray(m_timeStamps.data + startIndex, noOfPoints);
DoubleArray viewPortDataSeriesA = DoubleArray(m_dataSeriesA.data + startIndex, noOfPoints);
DoubleArray viewPortDataSeriesB = DoubleArray(m_dataSeriesB.data + startIndex, noOfPoints);
DoubleArray viewPortDataSeriesC = DoubleArray(m_dataSeriesC.data + startIndex, noOfPoints);
//
// At this stage, we have extracted the visible data. We can use those data to plot the chart.
//
///////////////////////////////////////////////////////////////////////////////////////
// Configure overall chart appearance.
///////////////////////////////////////////////////////////////////////////////////////
// Create an XYChart object of size 640 x 400 pixels
XYChart *c = new XYChart(640, 400);
// Set the plotarea at (55, 55) with width 80 pixels less than chart width, and height 92 pixels
// less than chart height. Use a vertical gradient from light blue (f0f6ff) to sky blue (a0c0ff)
// as background. Set border to transparent and grid lines to white (ffffff).
c->setPlotArea(55, 55, c->getWidth() - 80, c->getHeight() - 92, c->linearGradientColor(0, 55, 0,
c->getHeight() - 35, 0xf0f6ff, 0xa0c0ff), -1, Chart::Transparent, 0xffffff, 0xffffff);
// As the data can lie outside the plotarea in a zoomed chart, we need enable clipping.
c->setClipping();
// Add a title box using dark grey (0x333333) 15pt Arial Bold font
c->addTitle(" Zooming and Scrolling with Viewport Control", "Arial Bold", 15, 0x333333);
// Set legend icon style to use line style icon, sized for 10pt font
c->getLegend()->setLineStyleKey();
c->getLegend()->setFontSize(10);
// Set the x and y axis stems to transparent and the label font to 10pt Arial
c->xAxis()->setColors(Chart::Transparent);
c->yAxis()->setColors(Chart::Transparent);
c->xAxis()->setLabelStyle("Arial", 10);
c->yAxis()->setLabelStyle("Arial", 10);
// Add axis title using 10pt Arial Bold font
c->yAxis()->setTitle("Ionic Temperature (C)", "Arial Bold", 10);
///////////////////////////////////////////////////////////////////////////////////////
// Add data to chart
///////////////////////////////////////////////////////////////////////////////////////
//
// In this example, we represent the data by lines. You may modify the code below to use other
// representations (areas, scatter plot, etc).
//
// Add a line layer for the lines, using a line width of 2 pixels
LineLayer *layer = c->addLineLayer();
layer->setLineWidth(2);
// In this demo, we do not have too many data points. In real code, the chart may contain a lot
// of data points when fully zoomed out - much more than the number of horizontal pixels in this
// plot area. So it is a good idea to use fast line mode.
layer->setFastLineMode();
// Now we add the 3 data series to a line layer, using the color red (0xff3333), green
// (0x008800) and blue (0x3333cc)
layer->setXData(viewPortTimeStamps);
layer->addDataSet(viewPortDataSeriesA, 0xff3333, "Alpha");
layer->addDataSet(viewPortDataSeriesB, 0x008800, "Beta");
layer->addDataSet(viewPortDataSeriesC, 0x3333cc, "Gamma");
///////////////////////////////////////////////////////////////////////////////////////
// Configure axis scale and labelling
///////////////////////////////////////////////////////////////////////////////////////
// Set the x-axis as a date/time axis with the scale according to the view port x range.
viewer->syncDateAxisWithViewPort("x", c->xAxis());
// For the automatic y-axis labels, set the minimum spacing to 30 pixels.
c->yAxis()->setTickDensity(30);
//
// In this demo, the time range can be from a few years to a few days. We demonstrate how to
// set up different date/time format based on the time range.
//
// If all ticks are yearly aligned, then we use "yyyy" as the label format.
c->xAxis()->setFormatCondition("align", 360 * 86400);
c->xAxis()->setLabelFormat("{value|yyyy}");
// If all ticks are monthly aligned, then we use "mmm yyyy" in bold font as the first
// label of a year, and "mmm" for other labels.
c->xAxis()->setFormatCondition("align", 30 * 86400);
c->xAxis()->setMultiFormat(Chart::StartOfYearFilter(), "<*font=bold*>{value|mmm<*br*>yyyy}",
Chart::AllPassFilter(), "{value|mmm}");
// If all ticks are daily algined, then we use "mmm dd<*br*>yyyy" in bold font as the
// first label of a year, and "mmm dd" in bold font as the first label of a month, and
// "dd" for other labels.
c->xAxis()->setFormatCondition("align", 86400);
c->xAxis()->setMultiFormat(Chart::StartOfYearFilter(),
"<*block,halign=left*><*font=bold*>{value|mmm dd<*br*>yyyy}",
Chart::StartOfMonthFilter(), "<*font=bold*>{value|mmm dd}");
c->xAxis()->setMultiFormat(Chart::AllPassFilter(), "{value|dd}");
// For all other cases (sub-daily ticks), use "hh:nn<*br*>mmm dd" for the first label of
// a day, and "hh:nn" for other labels.
c->xAxis()->setFormatCondition("else");
c->xAxis()->setMultiFormat(Chart::StartOfDayFilter(), "<*font=bold*>{value|hh:nn<*br*>mmm dd}",
Chart::AllPassFilter(), "{value|hh:nn}");
///////////////////////////////////////////////////////////////////////////////////////
// Output the chart
///////////////////////////////////////////////////////////////////////////////////////
// We need to update the track line too. If the mouse is moving on the chart (eg. if
// the user drags the mouse on the chart to scroll it), the track line will be updated
// in the MouseMovePlotArea event. Otherwise, we need to update the track line here.
if (!viewer->isInMouseMoveEvent())
{
trackLineLegend(c, (0 == viewer->getChart()) ? c->getPlotArea()->getRightX() :
viewer->getPlotAreaMouseX());
}
delete viewer->getChart();
viewer->setChart(m_currentChart = c);
}
void ViewPortControlDemo::drawFullChart(QmlViewPortControl *vpc)
{
// Create an XYChart object of size 640 x 70 pixels
XYChart *c = new XYChart(640, 70);
// Set the plotarea with the same horizontal position as that in the main chart for alignment.
c->setPlotArea(55, 5, c->getWidth() - 80, c->getHeight() - 11, 0xc0d8ff, -1, 0x888888,
Chart::Transparent, 0xffffff);
// Set the x axis stem to transparent and the label font to 10pt Arial
c->xAxis()->setColors(Chart::Transparent);
c->xAxis()->setLabelStyle("Arial", 10);
// Put the x-axis labels inside the plot area by setting a negative label gap. Use
// setLabelAlignment to put the label at the right side of the tick.
c->xAxis()->setLabelGap(-1);
c->xAxis()->setLabelAlignment(1);
// Set the y axis stem and labels to transparent (that is, hide the labels)
c->yAxis()->setColors(Chart::Transparent, Chart::Transparent);
// Add a line layer for the lines with fast line mode enabled
LineLayer *layer = c->addLineLayer();
layer->setFastLineMode();
// Now we add the 3 data series to a line layer, using the color red (0xff3333), green
// (0x008800) and blue (0x3333cc)
layer->setXData(m_timeStamps);
layer->addDataSet(m_dataSeriesA, 0xff3333);
layer->addDataSet(m_dataSeriesB, 0x008800);
layer->addDataSet(m_dataSeriesC, 0x3333cc);
// The x axis scales should reflect the full range of the view port
QmlChartViewer *viewer = vpc->getViewer();
if (viewer)
c->xAxis()->setDateScale(viewer->getValueAtViewPort("x", 0), viewer->getValueAtViewPort("x", 1));
// For the automatic x-axis labels, set the minimum spacing to 75 pixels.
c->xAxis()->setTickDensity(75);
// For the auto-scaled y-axis, as we hide the labels, we can disable axis rounding. This can
// make the axis scale fit the data tighter.
c->yAxis()->setRounding(false, false);
// Output the chart
vpc->setChart(m_currentVpcChart = c);
}
//
// The Save button is pressed
//
void ViewPortControlDemo::saveChartImage(QmlChartViewer *viewer, QUrl url)
{
QString path = url.toLocalFile();
if (!path.isEmpty())
{
// Save the chart
BaseChart *c = viewer->getChart();
if (0 != c)
c->makeChart(path.toUtf8().constData());
}
}
//
// Draw track cursor when mouse is moving over plotarea
//
void ViewPortControlDemo::drawTrackCursor(QmlChartViewer *viewer, int mouseX)
{
trackLineLegend((XYChart *)viewer->getChart(), mouseX);
viewer->updateDisplay();
}
//
// Draw track line with data labels
//
void ViewPortControlDemo::trackLineLegend(XYChart *c, int mouseX)
{
// Clear the current dynamic layer and get the DrawArea object to draw on it.
DrawArea *d = c->initDynamicLayer();
// The plot area object
PlotArea *plotArea = c->getPlotArea();
// Get the data x-value that is nearest to the mouse, and find its pixel coordinate.
double xValue = c->getNearestXValue(mouseX);
int xCoor = c->getXCoor(xValue);
// Draw a vertical track line at the x-position
d->vline(plotArea->getTopY(), plotArea->getBottomY(), xCoor, 0xaaaaaa);
// Container to hold the legend entries
std::vector<std::string> legendEntries;
// Iterate through all layers to build the legend array
for (int i = 0; i < c->getLayerCount(); ++i) {
Layer *layer = c->getLayerByZ(i);
// The data array index of the x-value
int xIndex = layer->getXIndexOf(xValue);
// Iterate through all the data sets in the layer
for (int j = 0; j < layer->getDataSetCount(); ++j) {
DataSet *dataSet = layer->getDataSetByZ(j);
// We are only interested in visible data sets with names
const char *dataName = dataSet->getDataName();
int color = dataSet->getDataColor();
if (dataName && *dataName && (color != Chart::Transparent)) {
// Build the legend entry, consist of the legend icon, name and data value.
double dataValue = dataSet->getValue(xIndex);
std::ostringstream legendEntry;
legendEntry << "<*block*>" << dataSet->getLegendIcon() << " " << dataName << ": " <<
((dataValue == Chart::NoValue) ? "N/A" : c->formatValue(dataValue, "{value|P4}"))
<< "<*/*>";
legendEntries.push_back(legendEntry.str());
// Draw a track dot for data points within the plot area
int yCoor = c->getYCoor(dataSet->getPosition(xIndex), dataSet->getUseYAxis());
if ((yCoor >= plotArea->getTopY()) && (yCoor <= plotArea->getBottomY())) {
d->circle(xCoor, yCoor, 5, 5, color, color);
}
}
}
}
// Create the legend by joining the legend entries
std::ostringstream legendText;
legendText << "<*block,maxWidth=" << plotArea->getWidth() << "*><*block*><*font=Arial Bold*>["
<< c->xAxis()->getFormattedLabel(xValue, "mm/dd/yyyy") << "]<*/*>";
for (int i = ((int)legendEntries.size()) - 1; i >= 0; --i)
legendText << " " << legendEntries[i];
// Display the legend on the top of the plot area
TTFText *t = d->text(legendText.str().c_str(), "Arial Bold", 10);
t->draw(plotArea->getLeftX() + 5, plotArea->getTopY() - 3, 0x333333, Chart::BottomLeft);
t->destroy();
}
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