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diff --git a/examples/qmllegend/doc/src/qmllegend.qdoc b/examples/qmllegend/doc/src/qmllegend.qdoc new file mode 100644 index 00000000..14bacf06 --- /dev/null +++ b/examples/qmllegend/doc/src/qmllegend.qdoc @@ -0,0 +1,67 @@ +/**************************************************************************** +** +** Copyright (C) 2014 Digia Plc +** All rights reserved. +** For any questions to Digia, please use contact form at http://qt.digia.com +** +** This file is part of the QtDataVisualization module. +** +** Licensees holding valid Qt Enterprise licenses may use this file in +** accordance with the Qt Enterprise License Agreement provided with the +** Software or, alternatively, in accordance with the terms contained in +** a written agreement between you and Digia. +** +** If you have questions regarding the use of this file, please use +** contact form at http://qt.digia.com +** +****************************************************************************/ + +/*! + \example qmllegend + \title Qt Quick 2 Legend Example + \ingroup qtdatavisualization_examples + \brief Showing graph legend in a QML application. + + The Qt Quick 2 legend example shows how to make an interactive legend for a graph. + + \image qmllegend-example.png + + The interesting thing about this example is displaying the legend. We'll concentrate on + that and skip explaining the basic functionality - for + more detailed QML example documentation, see \l{Qt Quick 2 Scatter Example}. + + \section1 Legend + + The legend is simply a column of custom \c LegendItem items inside a transparent rectangle. + Each item is supplied with a series and the graph theme: + + \snippet ../examples/qmllegend/qml/qmllegend/main.qml 0 + + The legend items consist of a marker rectangle, which indicates the color of the series, + and a text field, which shows the name of the series. The colors we get from the series and + the theme supplied at legend item initialization: + + \snippet ../examples/qmllegend/qml/qmllegend/legenditem.qml 0 + \dots 4 + \snippet ../examples/qmllegend/qml/qmllegend/legenditem.qml 1 + + We want the legend to be interactive, so we add additional logic to enable selection of a + series by clicking on a legend item, as well as highlighting the legend item corresponding + to the selected series. + + The highlight depends on the selection state of the series, so we define two states, which + follow the Bar3DSeries::selectedBar property and adjust the \c legendItem color appropriately: + + \snippet ../examples/qmllegend/qml/qmllegend/legenditem.qml 3 + + To make the legend item interactive, we define a MouseArea to detect clicks on it and adjust + the series selection accordingly: + + \snippet ../examples/qmllegend/qml/qmllegend/legenditem.qml 2 + + The \c previousSelection used above is another custom property of \c LegendItem, which we update + whenever selection changes on the series. This way we remember the last selected bar of + each series: + + \snippet ../examples/qmllegend/qml/qmllegend/legenditem.qml 4 +*/ |