/****************************************************************************
**
** Copyright (C) 2019 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the Qt Creator documentation.
**
** 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.
**
****************************************************************************/

// **********************************************************************
// NOTE: the sections are not ordered by their logical order to avoid
// reshuffling the file each time the index order changes (i.e., often).
// Run the fixnavi.pl script to adjust the links to the index order.
// **********************************************************************

/*!
    \contentspage index.html
    \previouspage creator-tutorials.html
    \example transitions
    \nextpage creator-writing-program.html

    \title Creating a Qt Quick Application

    This tutorial uses built-in QML types and illustrates basic concepts of
    \l{Qt Quick}.
    For more information about the UI choices you have, see \l{User Interfaces}.


    This tutorial describes how to use \QC to implement Qt Quick states and
    transitions. We create an application that displays a Qt logo that moves
    between three rectangles on the page when you click them.

    \image qmldesigner-tutorial.png "States and transitions example"

    For more information about developing Qt Quick applications in the Design
    mode, see \l{Developing Qt Quick Applications}.

    For examples of using Qt Quick Controls, see \l{Qt Quick Controls Examples}.

    \include creator-tutorial-create-qq-project.qdocinc qt quick application

    \section1 Creating the Main View

    The main view of the application displays a Qt logo in the top left corner
    of the view and two empty rectangles.

    To use the \e qt-logo.png image in your application, you must copy it from
    the Qt examples directory to the project directory (same subdirectory as
    the QML file). The image appears in \uicontrol Resources. You can also use
    any other image or a QML type, instead.

    \list 1

        \li In the \uicontrol Projects view, double-click the \e Page1Form.ui.qml
            file to open it in the Design mode.

            \image qmldesigner-tutorial-design-mode.png "Transitions project in Design Mode"

        \li In the \uicontrol Navigator, select \uicontrol Label and press
            \key Delete to delete it.

        \li Select \uicontrol Page in the navigator, and enter \e page in the
            \uicontrol Id field.

        \li In \uicontrol Library > \uicontrol Resources, select qt-logo.png and
            drag and drop it to the \e page in the navigator.

            \image qmldesigner-tutorial-user-icon.png "Image properties"

        \list a

            \li In the \uicontrol Id field, enter \e icon.

            \li In the \uicontrol Position field, set \uicontrol X to \e 10 and
                \uicontrol Y to \e 20.

        \endlist

        \li Right-click the resource file, qml.qrc, in the \uicontrol Projects
            view, and select \uicontrol {Add Existing File} to add qt-logo.png
            to the resource file for deployment.

        \li Drag and drop a \uicontrol Rectangle to \e page in the navigator and
            edit its properties.

            \image qmldesigner-tutorial-topleftrect.png "Rectangle properties"

        \list a

            \li In the \uicontrol Id field, enter \e topLeftRect.

            \li In the \uicontrol Size field, set \uicontrol W to \e 55 and
                \uicontrol H to \e 41, for the rectangle size to match the image
                size.

            \li In the \uicontrol Color field, click the
                \inlineimage icon_color_none.png
                (\uicontrol Transparent) button to make the rectangle
                transparent.

            \li In the \uicontrol {Border color} field, set the border color to
                \e #808080.

            \li Click \uicontrol {Layout}, and then click the
                \inlineimage anchor-top.png
                (\uicontrol Top) and \inlineimage anchor-left.png
                (\uicontrol Left) anchor buttons to anchor the
                rectangle to the top left corner of the page.

            \li In the \uicontrol Margin field, select \e 20 for the top anchor
                and \e 10 for the left anchor.

                \image qmldesigner-tutorial-topleftrect-layout.png "Anchor margins"

        \endlist

        \li Drag and drop a \uicontrol {Mouse Area} type from the
            \uicontrol Library to \e topLeftRect in the navigator.

        \li Click \uicontrol {Layout}, and then click the
            \inlineimage anchor-fill.png
            (\uicontrol {Fill to Parent}) button to anchor the mouse area to the
            rectangle.

        \li In the \uicontrol Navigator, copy topLeftRect (by pressing
            \key {Ctrl+C}) and paste it to the \e page in the navigator twice
            (by pressing \key {Ctrl+V}). \QC renames the new instances of the
            type topLeftRect1 and topLeftRect2.

        \li  Select topLeftRect1 and edit its properties:

        \list a

            \li In the \uicontrol Id field, enter \e middleRightRect.

            \li In \uicontrol {Layout}, select the
                \inlineimage anchor-vertical-center.png
                (\uicontrol {Vertical Center} anchor button and then the
                \inlineimage anchor-right.png
                (\uicontrol Right) anchor button to anchor the rectangle
                to the middle right margin of its parent.

            \li In the \uicontrol Margin field, select \e 10 for the right
                anchor and \e 0 for the vertical center anchor.

        \endlist

        \li Select topLeftRect2 and edit its properties:

        \list a

            \li In the \uicontrol Id field, enter \e bottomLeftRect.

            \li In \uicontrol {Layout}, select the
                \inlineimage anchor-bottom.png
                (\uicontrol Bottom) and \inlineimage anchor-left.png
                (\uicontrol Left) anchor buttons to anchor the rectangle
                to the bottom left margin of its parent.

            \li In the \uicontrol Margin field, select \e 20 for the bottom
                anchor and \e 10 for the left anchor.

        \endlist

        \li In the \uicontrol Navigator, select the
            \inlineimage export_unchecked.png
            (\uicontrol Export) button for each type to export all types as
            properties. This enables you to use the properties in the
            \e main.qml file.

        \li Press \key {Ctrl+S} to save the changes.

    \endlist

    To check your code, you can view \e Page1Form.ui.qml in the
    \uicontrol {Text Editor} and compare it with the \l{transitions/Page1Form.ui.qml}
    {Page1Form.ui.qml} example file.

    The new project wizard adds boilerplate code to the \e Page1.qml file to
    create menu items and push buttons. Modify the boilerplate code by removing
    obsolete code. You removed the push buttons from the
    UI form, so you also need to remove the corresponding code from
    \e Page1.qml (or the application cannot be built).

    The UI is now ready and you can switch to editing the \e main.qml file in
    the \uicontrol {Text Editor} to add animation to the application, as described
    in the following section.

    \image qmldesigner-tutorial-ui-ready.png "Transitions UI"

    \section1 Adding Application Logic

    Edit the \e main.qml file to add pointers to two additional states: \e State1
    and \e State2. You cannot use the \uicontrol {Form Editor} to add states for
    a Window QML type. Use the \uicontrol {Text Editor} to add the states inside
    a StateGroup QML type and refer to them by using the id of the state group.

    \list 1

        \li Specify the window size and background color as properties of
            the ApplicationWindow type:

            \quotefromfile transitions/main.qml
            \skipto ApplicationWindow
            \printuntil title

        \li Specify an id for the Page1 type to be able to use the properties
            that you exported in \e Page1Form.ui.qml:

            \printuntil page

        \li Add a pointer to the clicked expressions in \uicontrol mouseArea:

            \printuntil }

            The expression sets the state to the base state and returns the
            image to its initial position.

        \li Add a pointer to a clicked expression to \uicontrol mouseArea1
            to set the state to \e State1:

            \printuntil }

        \li Add a pointer to a clicked expression to \uicontrol mouseArea2 to
            set the state to \e State2:

            \printuntil }
            \printuntil }

        \li Bind the position of the Qt logo to the
            rectangle to make sure that the logo is displayed within the
            rectangle when the view is scaled on different sizes of screens. Set
            expressions for the x and y properties, as illustrated by the
            following code snippet:

            \skipto StateGroup
            \printuntil ]

        \li Press \key {Ctrl+R} to run the application.

    \endlist

    Click the rectangles to move the Qt logo from one rectangle to another.

    \section1 Adding Animation to the View

    Add transitions inside the state group to define how the properties change
    when the Qt logo moves
    between states. The transitions apply animations to the Qt logo. For example,
    the Qt logo bounces back when it moves to the middleRightRect and eases into
    bottomLeftRect.

    \list 1

        \li In the \uicontrol {Text Editor}, add the following code to specify
            that when moving to State1, the x and y coordinates of the Qt logo
            change linearly over a duration of 1 second:

            \printuntil },

        \li You can use the Qt Quick toolbar for animation to change the easing
            curve type from linear to OutBounce:

        \list a

            \li Click \uicontrol NumberAnimation in the \uicontrol {Text Editor}
                to display the \inlineimage refactormarker.png
                icon, and then click the icon to open the toolbar:

                \image qmldesigner-tutorial-quick-toolbar.png "Qt Quick toolbar for animation"

            \li In the \uicontrol Easing field, select \uicontrol Bounce.

            \li In the \uicontrol Subtype field, select \uicontrol Out.

        \endlist

        \li Add the following code to specify that when moving to State2, the x
            and y coordinates of the Qt logo change over a duration of 2
            seconds, and an InOutQuad easing function is used:

            \dots
            \printuntil },

        \li Add the following code to specify that for any other state changes,
            the x and y coordinates of the Qt logo change linearly over a
            duration of 200 milliseconds:

            \dots
            \printuntil ]

        \li Press \key {Ctrl+R} to run the application.

    \endlist

    Click the rectangles to view the animated transitions.
*/
