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/****************************************************************************
**
** Copyright (c) 2014 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of Qt Creator
**
**
** GNU Free Documentation License
**
** 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.
**
**
****************************************************************************/
// **********************************************************************
// 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
\page creator-qml-application.html
\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}.
This tutorial describes how to use \QC to implement Qt states and transitions. We use
\l{Animation}{Qt example code} to
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 using \QMLD, see
\l{Developing Qt Quick Applications}.
\section1 Creating the Project
\list 1
\li Select \gui{File > New File or Project > Applications >
Qt Quick Application > Choose}.
\li In the \gui{Name} field, type \b {Transitions}.
\li In the \gui {Create in} field, enter the path for the project files.
For example, \c {C:\Qt\examples}, and then click \gui{Next} (on
Windows and Linux) or \gui Continue (on Mac OS).
\li In the \gui {Qt Quick component set} field, select
\gui {Qt Quick 2.0}.
\note The QML types used in this example are also supported in
Qt Quick 1.1. To create this example application for platforms that
run Qt 4, select \gui {Qt Quick 1.1}.
\li Select \l{glossary-buildandrun-kit}{kits} for running and building your project,
and then click \gui{Next}.
\note Kits are listed if they have been specified in \gui Tools >
\gui Options > \gui {Build & Run} > \gui Kits.
\li Select \gui Next in the following dialogs to use the default
settings.
\li Review the project settings, and click \gui{Finish} (on Windows and
Linux) or \gui Done (on Mac OS) to create the project.
\li Press \key {Ctrl+R} (or \key {Cmd+R}) to run the application.
\endlist
\QC generates a default QML file that you can modify to create the main view
of the application.
\image qmldesigner-tutorial-project.png "Transitions project in Edit mode"
\section1 Creating the Main View
The main view of the application displays a Qt logo in the top left corner
of the screen and two empty rectangles.
To use the states.png image in your application, you must copy it to the
project directory (same subdirectory as the QML file) from the examples
directory in the Qt installation directory. For example:
\c {C:\Qt\Qt5.0.1\5.0.1\msvc2010\examples\declarative\animation\states}. The image appears
in the \gui Resources pane. You can also use any other image or a QML
type, instead.
\list 1
\li In the \gui Projects view, double-click the main.qml file
to open it in the code editor.
\li Click \gui Design to open the file in \QMLD.
\image qmldesigner-tutorial-desing-mode.png "Transitions project in Design Mode"
\li In the \gui Navigator pane, select \gui Text and press \key Delete to
delete it.
\li Select \gui Rectangle to edit its properties.
\image qmldesigner-tutorial-page.png "Page properties"
\list a
\li In the \gui Id field, enter \e page, to be able to reference the
rectangle from other places.
\li In the \gui Color field, set the color to #343434.
\li In the code editor, delete the \c {Qt.quit();} command.
\endlist
\li In the \gui Library view, \gui Resources tab, select states.png and
drag and drop it to the canvas.
\image qmldesigner-tutorial-user-icon.png "Image properties"
\list a
\li In the \gui Id field, enter \e icon.
\li In the \gui Position field, set \gui X to 10 and \gui Y to 20.
\endlist
\li In the \gui Library view, \gui {QML Types} tab, select \gui Rectangle,
drag and drop it to the canvas, and edit its properties.
\image qmldesigner-tutorial-topleftrect.png "Rectangle properties"
\list a
\li In the \gui Id field, enter \e topLeftRect.
\li In the \gui Size field, set \gui W and \gui H to 64, for the
rectangle size to match the image size.
\li In the \gui Color field, click the
\inlineimage qmldesigner-transparent-button.png
(\gui Transparent) button to make the rectangle transparent.
\li In the \gui Border field, set the border color to #808080.
\li In the \gui Rectangle group, \gui Border field, set the border
width to 1.
\note If the \gui Border field does not appear after you set the
border color, try setting the border color to solid by clicking
the
\inlineimage qmldesigner-solid-color-button.png
(\gui {Solid Color}) button.
\li In the \gui Radius field, select 6 to create rounded corners for
the rectangle.
\li Click \gui {Layout}, and then click the top and left anchor
buttons to anchor the rectangle to the top left corner of the
page.
\image qmldesigner-tutorial-topleftrect-layout.png "Layout tab"
\li In the \gui Margin field, select 20 for the top anchor and 10
for the left anchor.
\endlist
\li In the \gui Navigator pane, drag and drop the \gui {Mouse Area}
from \e page to \e topLeftRect to make it apply only to the
rectangle and not to the whole page.
\li Edit the \gui {Mouse Area} properties:
\list a
\li Click \gui {Layout}, and then click the
\inlineimage qmldesigner-anchor-fill-screen.png
(\gui {Fill to Parent}) button to anchor the mouse area to the
rectangle.
\li In the code editor, edit the pointer to the clicked expression
in the mouse area, as illustrated by the following code
snippet:
\qml
MouseArea {
anchors.fill: parent
onClicked: page.state = ''
}
\endqml
The expression sets the state to the base state and returns the
image to its initial position.
\endlist
The qml.main file should now look as follows:
\snippet transitions/main.qml 0
\li In the \gui Navigator pane, copy topLeftRect (by pressing
\key {Ctrl+C}) and paste it to the canvas 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 \gui Id field, enter \e middleRightRect.
\li In \gui {Layout}, select the vertical center anchor button and
then the right anchor button to
anchor the rectangle to the middle right margin of the screen.
\li In the \gui Margin field, select 10 for the right anchor and 0
for the vertical center anchor.
\li In the code editor, add a pointer to a clicked expression to the
mouse area. The following expression sets the state to
\e State1:
\c {onClicked: page.state = 'State1'}
You will create State1 later.
\endlist
\li Select topLeftRect2 and edit its properties:
\list a
\li In the \gui Id field, enter \e bottomLeftRect.
\li In \gui {Layout}, select the bottom and left anchor buttons to
anchor the rectangle to the bottom left margin of the screen.
\li In the \gui Margin field, select 20 for the bottom anchor and 10
for the left anchor.
\li In the code editor, add a pointer to a clicked expression to the
mouse area. The following expression sets the state to
\e State2:
\c {onClicked: page.state = 'State2'}
You will create State2 later.
The qml.main file should now look as follows:
\snippet transitions/main.qml 1
\endlist
\li Press \key {Ctrl+S} to save the changes.
\li Press \key {Ctrl+R} to run the application.
\endlist
\image qmldesigner-tutorial.png "States and transitions example"
You should see the Qt logo in the top left rectangle, and two additional
rectangles in the center right and bottom left of the screen.
You can now create additional states to add views to the application.
\section1 Adding Views
In the .qml file, you already created pointers to two additional states:
State1 and State2. To create the states:
\list 1
\li Click the empty slot in the \gui States pane to create State1.
\li Click the empty slot in the \gui States pane to create State2.
\li In the code editor, 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:
\snippet qml/states-properties.qml states
\image qmldesigner-tutorial-state1.png "States"
\note When you set the expressions, drag and drop is disabled for
the icon in \QMLD.
\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 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. Add the transitions in the code editor.
\list 1
\li In the code 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:
\snippet qml/list-of-transitions.qml first transition
\li You can use the Qt Quick toolbar for animation to change the easing
curve type from linear to OutBounce:
\list a
\li Click \gui NumberAnimation in the code editor to display the
\inlineimage qml-toolbar-indicator.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 \gui Easing field, select \gui Bounce.
\li In the \gui Subtype field, select \gui 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:
\snippet qml/list-of-transitions.qml second transition
\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:
\snippet qml/list-of-transitions.qml default transition
\li Press \key {Ctrl+R} to run the application.
\endlist
Click the rectangles to view the animated transitions.
\section1 Example Code
When you have completed the steps, the main.qml file should look as follows:
\snippet transitions/main.qml 2
*/
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