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diff --git a/examples/datavisualization/customproxy/doc/src/customproxy.qdoc b/examples/datavisualization/customproxy/doc/src/customproxy.qdoc deleted file mode 100644 index 0952128e..00000000 --- a/examples/datavisualization/customproxy/doc/src/customproxy.qdoc +++ /dev/null @@ -1,122 +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 customproxy - \title Custom Proxy Example - \ingroup qtdatavisualization_examples - \brief Using Q3DBars with a custom proxy. - - The custom proxy example shows how to create a custom proxy to use with Q3DBars. - - \image customproxy-example.png - - The interesting thing about custom proxy example is the custom dataset and the corresponding - proxy usage, so we concentrate on that and skip explaining the basic Q3DBars functionality - - for that see \l{Bars Example}. - - This example defines a simple flexible data set \c VariantDataSet where each data item is a - a variant list. Each item can have multiple different values, identified by their index in - the list. In this example, the data set is storing monthly rainfall data, where the value in - index zero is the year, the value in index one is the month, and the value in index two is - the amount of rainfall in that month. - - The custom proxy we provide here is similar to item model based proxies provided by Qt - Data Visualization in that it requires a mapping to interpret the data. - - \include examples-run.qdocinc - - \section1 VariantDataSet - - \c VariantDataSet class provides a simple API: - - \snippet customproxy/variantdataset.h 1 - \dots 0 - \codeline - \snippet customproxy/variantdataset.h 0 - - As you can see, the data items are simply QVariantList objects, and the data can be added either - singly or in lists. The only additional functionality provided is clearing the data set and querying - for a reference to the data contained in the set. Signals are emitted when data is added or the set - is cleared. - - \section1 VariantBarDataProxy - - \c VariantBarDataProxy is a subclass of QBarDataProxy and provides a simple API of just getters - and setters for the data set and the mapping: - - \snippet customproxy/variantbardataproxy.h 0 - \dots 0 - \codeline - \snippet customproxy/variantbardataproxy.h 1 - - On the implementation side, the proxy listens for the changes in the data set and the mapping, - and resolves the data set if any changes are detected. It is not particularly efficient - implementation in that any change will cause re-resolving of the entire data set, but that is not - an issue for this example. The interesting part is the \c resolveDataSet() method: - - \snippet customproxy/variantbardataproxy.cpp 0 - - In \c resolveDataSet() method we sort the variant data values into rows and columns based on the - mapping. This is very similar to how QItemModelBarDataProxy handles mapping, except we use - list indexes instead of item model roles here. Once the values are sorted, we generate \c QBarDataArray - out of them, and call \c resetArray() method on the parent class. - - \section1 VariantBarDataMapping - - \c VariantBarDataMapping stores the mapping information between \c VariantDataSet data item indexes - and rows, columns, and values of \c QBarDataArray. It also contains the lists of rows and columns to - be included in the resolved data: - - \snippet customproxy/variantbardatamapping.h 0 - \dots 0 - \codeline - \snippet customproxy/variantbardatamapping.h 1 - \dots 0 - \codeline - \snippet customproxy/variantbardatamapping.h 2 - \dots 0 - \codeline - \snippet customproxy/variantbardatamapping.h 3 - - The primary way to use a \c VariantBarDataMapping object is to give the mappings already at the - constructor, though they can be set later individually or all together with the \c remap() method. - A signal is emitted if mapping changes. It is basically a simplified version of the mapping - functionality of QItemModelBarDataProxy adapted to work with variant lists instead of item models. - - \section1 RainfallGraph - - \c RainfallGraph class handles the setup of the graph. The interesting part is the \c addDataSet() - method: - - \snippet customproxy/rainfallgraph.cpp 0 - - The bulk of that method is used for populating the variant data set. Once the set is populated, - visualizing the data is trivial with the help of our custom proxy: - - \snippet customproxy/rainfallgraph.cpp 1 -*/ |