// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only

/*!
    \example qmlscatter
    \title Qt Quick 2 Scatter Example
    \ingroup qtdatavisualization_examples
    \brief Using Scatter3D in a QML application.

    The Qt Quick 2 scatter example shows how to make a simple scatter graph visualization using
    Scatter3D and Qt Quick 2.

    For instructions about how to interact with the graph, see \l{Qt Data Visualization Interacting with Data}{this page}.

    For instructions how to create a new Qt Quick 2 application of your own, see Qt Creator help.

    \image qmlscatter-example.png

    \include examples-run.qdocinc

    \section1 Application Basics

    Before diving into the QML code, let's take a look at the application \c main.cpp.

    This application implements a 'Quit' button in the UI, so we want to connect the QQmlEngine::quit()
    signal to our application's QWindow::close() slot:

    \snippet qmlscatter/main.cpp 4

    To make deployment little simpler, we gather all of the application's \c .qml files to a resource
    file (\c qmlscatter.qrc):

    \code
    <RCC>
        <qresource prefix="/">
            <file>qml/qmlscatter/Data.qml</file>
            <file>qml/qmlscatter/main.qml</file>
        </qresource>
    </RCC>
    \endcode

    This also requires us to set the \c main.qml to be read from the resource (\c{qrc:}):

    \snippet qmlscatter/main.cpp 3

    Lastly, we want the application to run in a maximized window:

    \snippet qmlscatter/main.cpp 2

    \section1 Setting up the Graph

    First we'll import all the QML modules we need:

    \snippet qmlscatter/qml/qmlscatter/main.qml 0

    The last \c import just imports all the qml files in the same directory as our \c {main.qml},
    because that's where \c Data.qml is.

    Then we create our main \c Item and call it \c mainView:

    \snippet qmlscatter/qml/qmlscatter/main.qml 1

    Then we'll add another \c Item inside the main \c Item, and call it \c dataView.
    This will be the item to hold the Scatter3D graph. We'll anchor it to the parent bottom:

    \snippet qmlscatter/qml/qmlscatter/main.qml 9

    Next we're ready to add the Scatter3D graph itself. We'll add it inside the \c dataView and
    name it \c {scatterGraph}. Let's make it fill the \c {dataView}:

    \snippet qmlscatter/qml/qmlscatter/main.qml 2

    Now the graph is ready for use, but has no data. It also has the default axes and visual
    properties.

    Let's modify some visual properties first by adding the following inside \c {scatterGraph}:

    \snippet qmlscatter/qml/qmlscatter/main.qml 3

    We added a customized theme and changed the shadow quality.
    We're happy with the other visual properties, so we won't change them.

    The custom theme is based on a predefined theme, but we change the font in it:

    \snippet qmlscatter/qml/qmlscatter/main.qml 13

    Then it's time to start feeding the graph some data.

    \section1 Adding Data to the Graph

    Let's create a \c Data item inside the \c mainView and name it \c seriesData:

    \snippet qmlscatter/qml/qmlscatter/main.qml 4

    The \c seriesData item contains the data models for all three series we use in this example.

    This is the component that holds our data in \c {Data.qml}. It has an \c Item as the main
    component.

    In the main component we'll add the data itself in a \c ListModel and name it
    \c {dataModel}:

    \snippet qmlscatter/qml/qmlscatter/Data.qml 0
    \dots

    We'll add two more of these for the other two series, and name them \c dataModelTwo and
    \c {dataModelThree}.

    Then we need to expose the data models to be usable from \c {main.qml}. We do this by defining
    them as aliases in the main data component:

    \snippet qmlscatter/qml/qmlscatter/Data.qml 1

    Now we can use the data from \c Data.qml with \c scatterGraph in \c {main.qml}. First we'll add
    a Scatter3DSeries and call it \c {scatterSeries}:

    \snippet qmlscatter/qml/qmlscatter/main.qml 5

    Then we'll set up selection label format for the series:

    \snippet qmlscatter/qml/qmlscatter/main.qml 10

    And finally the data for series one in a ItemModelScatterDataProxy. We set the data itself as
    \c itemModel for the proxy:

    \snippet qmlscatter/qml/qmlscatter/main.qml 11

    We'll add the other two series in the same way, but modify some series-specific details a bit:

    \snippet qmlscatter/qml/qmlscatter/main.qml 12
    \dots

    Then we'll modify the properties of the default axes in \c scatterGraph a bit:

    \snippet qmlscatter/qml/qmlscatter/main.qml 6

    After that we'll just add a few buttons to the \c mainView to control the graph. We'll only
    show one as an example:

    \snippet qmlscatter/qml/qmlscatter/main.qml 7

    Then we'll modify \c dataView to make room for the buttons at the top:

    \snippet qmlscatter/qml/qmlscatter/main.qml 8
    \dots

    And we're done!

    \section1 Example Contents
*/
