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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 {Qt Creator Manual}
\previouspage quick-components.html
\page quick-buttons.html
\nextpage quick-scalable-image.html
\title Creating Buttons
To create a button component:
\list 1
\li Select \uicontrol {File > New File or Project > Qt > QML File > Choose}
to create a QML file called Button.qml (for example).
\note Components are listed in the \uicontrol Library only if the
filename begins with a capital letter.
\li Click \uicontrol {Design} to edit the file in the visual editor.
\li In the \uicontrol Navigator, click \uicontrol Rectangle to set properties
for it.
\li In the \uicontrol Properties pane, modify the appearance of the button.
\list a
\li In the \uicontrol Size field, set the width (\uicontrol W) and height
(\uicontrol H) of the button.
\li In the \uicontrol Color field, select the button color.
\li In the \uicontrol Radius field, use the slider to set the radius of
the rectangle and produce rounded corners for the button.
\endlist
\li Drag and drop a \uicontrol {Text} item on top of the \uicontrol Rectangle. This
creates a nested item where \uicontrol Rectangle is the parent item
of \uicontrol Text. Items are positioned relative to their parents.
\li In the \uicontrol Properties pane, edit the properties of the \uicontrol Text
item.
\list a
\li In the \uicontrol Text field, type \b Button.
You can select the text color in the \uicontrol {Text color} field and the
font, size, and style in the
\uicontrol Font section.
\li In the \uicontrol Alignment field, select the center buttons to align
the text to the center of the button.
\li Click \uicontrol {Layout}, and then click the
\inlineimage qmldesigner-anchor-fill-screen.png
(\uicontrol {Fill to Parent}) button to anchor the text to the whole
button area.
\endlist
\li Press \key {Ctrl+S} to save the button.
\image qmldesigner-button.png "Button component"
\endlist
To create a graphical button that scales beautifully without using vector
graphics, use the \l{BorderImage} type. For more information, see
\l{Creating Scalable Buttons and Borders}.
*/
/*!
\contentspage {Qt Creator Manual}
\previouspage quick-buttons.html
\page quick-scalable-image.html
\nextpage quick-screens.html
\title Creating Scalable Buttons and Borders
You can use the
\l{BorderImage} type to display an image, such as a PNG file, as a border
and a background.
Use two Border Image items and suitable graphics to make it look like the
button is pushed down when it is clicked. One of the Border Image items
is visible by default. You can specify that it is hidden and the other one
becomes visible when the mouse is clicked.
Add a Mouse Area that covers the whole area and emits the clicked signal
(\c {parent.clicked()}) when it detects a mouse click.
You can add text to the button and set it up as a property. The text can
then be initialized from the outside, making the button a reusable UI
component. The font size is also available in case the default size is too
big. You can scale down the button text and use smooth text rendering for
some extra quality.
\image qmldesigner-borderimage.png "Graphical button"
To create a graphical button:
\list 1
\li Select \uicontrol {File > New File or Project > Qt > QML File > Choose}
to create a QML file called Button.qml (for example).
\li Double-click the file to open it in the code editor.
\li Replace the \uicontrol Rectangle with an \uicontrol Item, as illustrated by the
following code snippet:
\qml
Item {
}
\endqml
\li Specify properties and set expressions for the \uicontrol Item, as
illustrated by the following code snippet:
\qml
Item {
property string text: ""
property int fontSize: 10
signal clicked
width: 60
height: 40
}
\endqml
You will point to the properties and expression later.
\li Click \uicontrol {Design} to edit the file in the visual editor.
\li Drag and drop two \uicontrol {Border Image} items from the \uicontrol Library
to the canvas.
\li Drag and drop a \uicontrol Text item to the canvas.
\li Drag and drop a \uicontrol {Mouse Area} to the canvas.
\li In the \uicontrol Navigator, select \uicontrol border_image1 to specify
settings for it in the \uicontrol Properties pane:
\list a
\li Select \uicontrol {Set Binding} in the menu next to the
\uicontrol Visibility check box.
\li Enter the following expression to specify that the image is
visible when the mouse is not pressed down:
\c {!mouse_area1.pressed}.
\li In the \uicontrol Source field, select the image file for the button,
for example button_up.png.
\li Click \uicontrol {Layout}, and then click the
\inlineimage qmldesigner-anchor-fill-screen.png
(\uicontrol {Fill to Parent}) button to anchor the border image to the
\uicontrol Item.
\endlist
\li Select \uicontrol border_image2 to specify similar settings for it:
\list a
\li Set the following epression for \uicontrol Visibility, to specify that
the image is visible when the mouse is pressed down:
\c {mouse_area1.pressed}.
\li In the \uicontrol Source field, select the image file for the button
when it is clicked, for example button_down.png.
\li Click \uicontrol {Layout}, and then click the
\uicontrol {Fill to Parent}
button to anchor the border image to the \uicontrol Item.
\endlist
\li Select \uicontrol text1 to specify font size and color, and text
scaling and rendering:
\list a
\li In the \uicontrol Color field, use the color picker to select
the font color, or enter a value in the field.
\li In the \uicontrol Text field, select \uicontrol {Set Binding} and
enter a pointer to the \c {text} property that you specified
earlier: \c {parent.txt}.
\li In the \uicontrol Size field, select \uicontrol {Pixels} to specify the font
size in pixels. By default, the size is specified in points.
\li In the \uicontrol Size field, select \uicontrol {Set Expression} and enter a
pointer to the \c {fontSize} property that you specified
earlier.
\li Click \uicontrol {Layout}, and then click the
\inlineimage qmldesigner-center-in.png "Anchor buttons"
(\uicontrol {Set Vertical Anchor} and \uicontrol {Set Horizontal Anchor})
buttons to inherit the vertical and horizontal centering from
the parent.
\li Click \uicontrol Advanced to specify scaling for the text in the
\uicontrol Scale field.
\li Select \uicontrol {Set Binding} and enter the following expression:
\c {if (!mousearea1.pressed) { 1 } else { 0.95 }}.
\note You can enter long and complicated expressions also in the
code editor.
\endlist
\li In the code editor, add to the \c MouseArea a pointer to the
\c clicked expression that you added earlier:
\c {onClicked: parent.clicked()}.
\endlist
\note To test the button, add it to a Qt Quick Application or Qt
Quick UI project and run the application.
*/
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