qzxing/examples/QMLBarcodeScanner/ZoomControl.qml

119 lines
3.9 KiB
QML

/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Mobility Components.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
** the names of its contributors may be used to endorse or promote
** products derived from this software without specific prior written
** permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
** $QT_END_LICENSE$
**
****************************************************************************/
import Qt 4.7
import QtMultimediaKit 1.1
Item {
id : zoomControl
property real currentZoom : 1
property real maximumZoom : 1
signal zoomTo(real value)
MouseArea {
id : mouseArea
anchors.fill: parent
property real initialZoom : 0
property real initialPos : 0
onPressed: {
initialPos = mouseY
initialZoom = zoomControl.currentZoom
}
onMousePositionChanged: {
if (pressed) {
var target = initialZoom * Math.pow(2, (initialPos-mouseY)/zoomControl.height);
target = Math.max(1, Math.min(target, zoomControl.maximumZoom))
zoomControl.zoomTo(target)
}
}
}
Item {
id : bar
x : 16
y : parent.height/4
width : 24
height : parent.height/2
opacity : 0
Rectangle {
anchors.fill: parent
smooth: true
radius: 8
border.color: "black"
border.width: 2
color: "white"
opacity: 0.3
}
Rectangle {
x : 0
y : parent.height * (1.0 - (zoomControl.currentZoom-1.0) / (zoomControl.maximumZoom-1.0))
width: parent.width
height: parent.height - y
smooth: true
radius: 8
color: "black"
opacity: 0.5
}
states: State {
name: "ShowBar"
when: mouseArea.pressed || zoomControl.currentZoom > 1.0
PropertyChanges { target: bar; opacity: 1 }
}
transitions: [
Transition {
to : "ShowBar"
NumberAnimation { properties: "opacity"; duration: 100 }
},
Transition {
from : "ShowBar"
NumberAnimation { properties: "opacity"; duration: 500 }
}
]
}
}