~zsombi/ubuntu-ui-toolkit/statesaver-signals

/*

 * Copyright 2013 Canonical Ltd.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU Lesser General Public License as published by

 * the Free Software Foundation; version 3.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 *

 * Author: Florian Boucault <florian.boucault@canonical.com>

 */

import QtQuick 2.0

import Ubuntu.Components 0.1

Item {

    id: buttonStyle

    property Button button: styledItem

    property real minimumWidth: units.gu(10)

    property real horizontalPadding: units.gu(1)

    property color defaultColor: UbuntuColors.orange

    property Gradient defaultGradient

    width: button.width

    height: button.height

    implicitWidth: Math.max(minimumWidth, foreground.implicitWidth + 2*horizontalPadding)

    implicitHeight: units.gu(4)

    LayoutMirroring.enabled: Qt.application.layoutDirection == Qt.RightToLeft

    LayoutMirroring.childrenInherit: true

    /* The proxy is necessary because Gradient.stops and GradientStop.color are

       non-NOTIFYable properties. They cannot be written to so it is fine but

       the proxy avoids the warnings.

    */

    QtObject {

        id: gradientProxy

        property color topColor

        property color bottomColor

        function updateGradient() {

            if (button.gradient) {

                topColor = button.gradient.stops[0].color;

                bottomColor = button.gradient.stops[1].color;

            }

        }

        Component.onCompleted: {

            updateGradient();

            button.gradientChanged.connect(updateGradient);

        }

    }

    // Use the gradient if it is defined and the color has not been set manually

    // or the gradient has been set manually

    property bool isGradient: button.gradient && (button.color == defaultColor ||

                              button.gradient != defaultGradient)

    UbuntuShape {

        id: background

        anchors.fill: parent

        borderSource: "radius_idle.sci"

        visible: color.a != 0.0

        // Color properties in a JS ternary operator don't work as expected in

        // QML because it overwrites alpha values with 1. A workaround is to use

        // Qt.rgba(). For more information, see

        // https://bugs.launchpad.net/ubuntu-ui-toolkit/+bug/1197802 and

        // https://bugreports.qt-project.org/browse/QTBUG-32238.

        function colorHack(color) { return Qt.rgba(color.r, color.g, color.b, color.a); }

        color: isGradient ? colorHack(gradientProxy.topColor) : colorHack(button.color)

        gradientColor: isGradient ? colorHack(gradientProxy.bottomColor) : colorHack(button.color)

    }

    UbuntuShape {

        id: backgroundPressed

        anchors.fill: parent

        color: background.color

        gradientColor: background.gradientColor

        borderSource: "radius_pressed.sci"

        opacity: button.pressed ? 1.0 : 0.0

        Behavior on opacity {

            NumberAnimation {

                duration: UbuntuAnimation.SnapDuration

                easing.type: Easing.Linear

            }

        }

        visible: background.visible

    }

    ButtonForeground {

        id: foreground

        width: parent.width - 2*horizontalPadding

        anchors.centerIn: parent

        text: button.text

        /* Pick either a clear or dark text color depending on the luminance of the

           background color to maintain good contrast (works in most cases)

        */

        textColor: ColorUtils.luminance(button.color) <= 0.85 ? "#F3F3E7" : "#888888"

        iconSource: button.iconSource

        iconPosition: button.iconPosition

        iconSize: units.gu(3)

        spacing: horizontalPadding

        transformOrigin: Item.Top

        scale: button.pressed ? 0.98 : 1.0

        Behavior on scale {

            NumberAnimation {

                duration: UbuntuAnimation.SnapDuration

                easing.type: Easing.Linear

            }

        }

    }

}