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diff --git a/examples/datavisualization/qmlaxisformatter/doc/src/qmlaxisformatter.qdoc b/examples/datavisualization/qmlaxisformatter/doc/src/qmlaxisformatter.qdoc deleted file mode 100644 index 3c9574d4..00000000 --- a/examples/datavisualization/qmlaxisformatter/doc/src/qmlaxisformatter.qdoc +++ /dev/null @@ -1,126 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2016 The Qt Company Ltd. -** Contact: https://www.qt.io/licensing/ -** -** This file is part of the documentation of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:FDL$ -** Commercial License Usage -** Licensees holding valid commercial Qt licenses may use this file in -** accordance with the commercial license agreement provided with the -** Software or, alternatively, in accordance with the terms contained in -** a written agreement between you and The Qt Company. For licensing terms -** and conditions see https://www.qt.io/terms-conditions. For further -** information use the contact form at https://www.qt.io/contact-us. -** -** GNU Free Documentation License Usage -** Alternatively, this file may be used under the terms of the GNU Free -** Documentation License version 1.3 as published by the Free Software -** Foundation and appearing in the file included in the packaging of -** this file. Please review the following information to ensure -** the GNU Free Documentation License version 1.3 requirements -** will be met: https://www.gnu.org/licenses/fdl-1.3.html. -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! - \example qmlaxisformatter - \title Qt Quick 2 Axis Formatter Example - \ingroup qtdatavisualization_examples - \brief Example of a hybrid C++ and QML application demonstrating different axis formatters. - \since QtDataVisualization 1.1 - - The Qt Quick axis formatter example shows how to use predefined axis formatters and how to - create a custom one. - - \image qmlaxisformatter-example.png - - The interesting thing about this example is axis formatters, so we'll concentrate on - that and skip explaining the basic functionality - for - more detailed QML example documentation, see \l{Qt Quick 2 Scatter Example}. - - \include examples-run.qdocinc - - \section1 Custom Axis Formatter - - Customizing axis formatters requires subclassing the QValue3DAxisFormatter, which cannot be - done in QML code alone. In this example we want an axis that interprets the float values as - a timestamp and shows the date in the axis labels. To achieve this, we introduce a new class - called \c CustomFormatter, which subclasses the QValue3DAxisFormatter: - - \snippet qmlaxisformatter/customformatter.h 2 - \dots 0 - - Since float values of a QScatter3DSeries cannot be directly cast into QDateTime values due to - difference in data width, we need some sort of mapping between the two. We chose to do the - mapping by specifying an origin date for the formatter and interpreting the float values - from the QScatter3DSeries as date offsets to that origin value. The origin date is given as - a property: - - \snippet qmlaxisformatter/customformatter.h 1 - - The mapping from value to QDateTime is done using \c valueToDateTime() method: - - \snippet qmlaxisformatter/customformatter.cpp 0 - - To function as an axis formatter, our \c CustomFormatter needs to reimplement some virtual - methods: - - \snippet qmlaxisformatter/customformatter.h 0 - - The first two are simple, we just create a new instance of \c CustomFormatter and copy the - necessary data over to it. These two methods are used to create and update a cache of formatter for - rendering purposes. It is important to remember to call the superclass implementation - of \c populateCopy(): - - \snippet qmlaxisformatter/customformatter.cpp 1 - - Bulk of the work done by \c CustomFormatter is done in the \c recalculate() method, where - our formatter calculates the grid, subgrid, and label positions, as well as formats the label - strings. - In our custom formatter we ignore the segment count of the axis and draw a grid line always at - midnight. Subsegment count and label positioning is handled normally: - - \snippet qmlaxisformatter/customformatter.cpp 2 - - The axis labels are formatted to show only the date, but for selection label we want little more - resolution for the timestamp, so we specify another property for our custom formatter to allow - user to customize it: - - \snippet qmlaxisformatter/customformatter.h 3 - - This selection format property is used in the reimplemented \c stringToValue method, where we - ignore the submitted format and substitute the custom selection format for it: - - \snippet qmlaxisformatter/customformatter.cpp 3 - - To expose our new custom formatter to the QML, we must declare and register it: - - \snippet qmlaxisformatter/main.cpp 0 - \dots 0 - \snippet qmlaxisformatter/main.cpp 1 - - \section1 QML - - In the QML codes, we define a different axis for each dimension: - - \snippet qmlaxisformatter/qml/qmlaxisformatter/main.qml 3 - - Z-axis is just a regular ValueAxis3D: - - \snippet qmlaxisformatter/qml/qmlaxisformatter/main.qml 0 - - For the Y-axis we define a logarithmic axis. ValueAxis3D can be made to show logarithmic scale - by specifying LogValueAxis3DFormatter for \c formatter property of the axis: - - \snippet qmlaxisformatter/qml/qmlaxisformatter/main.qml 2 - - And finally, for the X-axis we use our new \c CustomFormatter: - - \snippet qmlaxisformatter/qml/qmlaxisformatter/main.qml 1 - - Rest of the application consists of fairly self-explanatory logic for modifying the axes and - showing the graph. -*/ |