Skip to content
DropButton.qml 8.88 KiB
Newer Older
dogmaphobic's avatar
dogmaphobic committed
import QtQuick                  2.4
Don Gagne's avatar
Don Gagne committed
import QtQuick.Controls         1.2
import QtQuick.Controls.Styles  1.2

import QGroundControl.ScreenTools   1.0
import QGroundControl.Palette       1.0

Item {
    id: _root

    property alias  buttonImage:        button.source
    property real   radius:             (ScreenTools.defaultFontPixelHeight * 3) / 2
Don Gagne's avatar
Don Gagne committed
    property int    dropDirection:      dropDown
    property alias  dropDownComponent:  dropDownLoader.sourceComponent
    property real   viewportMargins:    0

    width:  radius * 2
    height: radius * 2

    // Should be an enum but that get's into the whole problem of creating a singleton which isn't worth the effort
    readonly property int dropLeft:     1
    readonly property int dropRight:    2
    readonly property int dropUp:       3
    readonly property int dropDown:     4

    function hideDropDown() {
        _showDropDown = false
    }

    readonly property real _arrowBaseWidth:     (radius * 2) / 2    // Width of long side of arrow
    readonly property real _arrowPointHeight:   (radius * 2) / 3    // Height is long side to point
    readonly property real _dropCornerRadius:   ScreenTools.defaultFontPixelWidth / 2
    readonly property real _dropCornerRadiusX2: _dropCornerRadius * 2
    readonly property real _dropMargin:         _dropCornerRadius
    readonly property real _dropMarginX2:       _dropMargin * 2

    property real   _viewportMaxLeft:   -x + viewportMargins
    property real   _viewportMaxRight:  parent.width - (viewportMargins * 2) - x
    property real   _viewportMaxTop:    -y + viewportMargins
    property real   _viewportMaxBottom: parent.height - (viewportMargins * 2) - y

    property bool _showDropDown: false

    Component.onCompleted: _calcPositions()

    function _calcPositions() {
        var dropComponentWidth = dropDownLoader.item.width
        var dropComponentHeight = dropDownLoader.item.height
        var dropRectWidth = dropComponentWidth + _dropMarginX2
        var dropRectHeight = dropComponentHeight + _dropMarginX2

        dropItemHolderRect.width = dropRectWidth
        dropItemHolderRect.height = dropRectHeight

        dropDownItem.width = dropComponentWidth + _dropMarginX2
        dropDownItem.height = dropComponentHeight + _dropMarginX2

        if (dropDirection == dropUp || dropDirection == dropDown) {
            dropDownItem.height += _arrowPointHeight

            dropDownItem.x = -(dropDownItem.width / 2) + radius

            dropItemHolderRect.x = 0

            if (dropDirection == dropUp) {
                dropDownItem.y = -(dropDownItem.height + _dropMargin)

                dropItemHolderRect.y = 0
            } else {
                dropDownItem.y = button.height + _dropMargin

                dropItemHolderRect.y = _arrowPointHeight
            }

            // Validate that dropdown is within viewport
            dropDownItem.x = Math.max(dropDownItem.x, _viewportMaxLeft)
            dropDownItem.x = Math.min(dropDownItem.x + dropDownItem.width, _viewportMaxRight) - dropDownItem.width

            // Arrow points
            arrowCanvas.arrowPoint.x = (button.x + radius) - dropDownItem.x
            if (dropDirection == dropUp) {
                arrowCanvas.arrowPoint.y = dropDownItem.height
                arrowCanvas.arrowBase1.x = arrowCanvas.arrowPoint.x - (_arrowBaseWidth / 2)
                arrowCanvas.arrowBase1.y = arrowCanvas.arrowPoint.y - _arrowPointHeight
                arrowCanvas.arrowBase2.x = arrowCanvas.arrowBase1.x + _arrowBaseWidth
                arrowCanvas.arrowBase2.y = arrowCanvas.arrowBase1.y
            } else {
                arrowCanvas.arrowPoint.y = 0
                arrowCanvas.arrowBase1.x = arrowCanvas.arrowPoint.x + (_arrowBaseWidth / 2)
                arrowCanvas.arrowBase1.y = _arrowPointHeight
                arrowCanvas.arrowBase2.x = arrowCanvas.arrowBase1.x - _arrowBaseWidth
                arrowCanvas.arrowBase2.y = arrowCanvas.arrowBase1.y
            }
        } else {
            dropDownItem.width += _arrowPointHeight

            dropDownItem.y = -(dropDownItem.height / 2) + radius

            dropItemHolderRect.y = 0

            if (dropDirection == dropLeft) {
                dropDownItem.x = dropDownItem.width + _dropMargin

                dropItemHolderRect.x = 0
            } else {
                dropDownItem.x = button.width + _dropMargin

                dropItemHolderRect.x = _arrowPointHeight
            }

            // Validate that dropdown is within viewport
            dropDownItem.y = Math.max(dropDownItem.y, _viewportMaxTop)
            dropDownItem.y = Math.min(dropDownItem.y + dropDownItem.height, _viewportMaxBottom) - dropDownItem.height

            // Arrow points
            arrowCanvas.arrowPoint.y = (button.y + radius) - dropDownItem.y
            if (dropDirection == dropLeft) {
                arrowCanvas.arrowPoint.x = dropDownItem.width
                arrowCanvas.arrowBase1.x = arrowCanvas.arrowPoint.x - _arrowPointHeight
                arrowCanvas.arrowBase1.y = arrowCanvas.arrowPoint.y - (_arrowBaseWidth / 2)
                arrowCanvas.arrowBase2.x = arrowCanvas.arrowBase1.x
                arrowCanvas.arrowBase2.y = arrowCanvas.arrowBase1.y + _arrowBaseWidth
            } else {
                arrowCanvas.arrowPoint.x = 0
                arrowCanvas.arrowBase1.x = _arrowPointHeight
                arrowCanvas.arrowBase1.y = arrowCanvas.arrowPoint.y - (_arrowBaseWidth / 2)
                arrowCanvas.arrowBase2.x = arrowCanvas.arrowBase1.x
                arrowCanvas.arrowBase2.y = arrowCanvas.arrowBase1.y + _arrowBaseWidth
            }
        }
        arrowCanvas.requestPaint()
    } // function - _calcPositions

    QGCPalette { id: qgcPal }

    MouseArea {
        x:          _viewportMaxLeft
        y:          _viewportMaxTop
        width:      _viewportMaxRight -_viewportMaxLeft
        height:     _viewportMaxBottom - _viewportMaxTop
        visible:    _showDropDown

        onClicked: _showDropDown = false
    }

    // Button
Don Gagne's avatar
Don Gagne committed
        id:             button
        anchors.fill:   parent
        fillMode:       Image.PreserveAspectFit
Don Gagne's avatar
Don Gagne committed
        opacity:        _showDropDown ? 1.0 : 0.75
dogmaphobic's avatar
dogmaphobic committed
        mipmap:         true
        smooth:         true
Don Gagne's avatar
Don Gagne committed
        MouseArea {
            anchors.fill: parent

            onClicked: _showDropDown = !_showDropDown
        }
    } // Image - button
Don Gagne's avatar
Don Gagne committed

    Item {
        id:         dropDownItem
        visible:    _showDropDown

        QGCCanvas {
Don Gagne's avatar
Don Gagne committed
            id:             arrowCanvas
            anchors.fill:   parent

            property var arrowPoint: Qt.point(0, 0)
            property var arrowBase1: Qt.point(0, 0)
            property var arrowBase2: Qt.point(0, 0)

            onPaint: {
                var context = getContext("2d")
                context.reset()
                context.beginPath()

                context.moveTo(dropItemHolderRect.x, dropItemHolderRect.y)
                if (dropDirection == dropDown) {
                    context.lineTo(arrowBase2.x, arrowBase2.y)
                    context.lineTo(arrowPoint.x, arrowPoint.y)
                    context.lineTo(arrowBase1.x, arrowBase1.y)
                }
                context.lineTo(dropItemHolderRect.x + dropItemHolderRect.width, dropItemHolderRect.y)
                if (dropDirection == dropLeft) {
                    context.lineTo(arrowBase2.x, arrowBase2.y)
                    context.lineTo(arrowPoint.x, arrowPoint.y)
                    context.lineTo(arrowBase1.x, arrowBase1.y)
                }
                context.lineTo(dropItemHolderRect.x + dropItemHolderRect.width, dropItemHolderRect.y + dropItemHolderRect.height)
                if (dropDirection == dropUp) {
                    context.lineTo(arrowBase2.x, arrowBase2.y)
                    context.lineTo(arrowPoint.x, arrowPoint.y)
                    context.lineTo(arrowBase1.x, arrowBase1.y)
                }
                context.lineTo(dropItemHolderRect.x, dropItemHolderRect.y + dropItemHolderRect.height)
                if (dropDirection == dropRight) {
                    context.lineTo(arrowBase2.x, arrowBase2.y)
                    context.lineTo(arrowPoint.x, arrowPoint.y)
                    context.lineTo(arrowBase1.x, arrowBase1.y)
                }
                context.lineTo(dropItemHolderRect.x, dropItemHolderRect.y)

                context.closePath()
                context.fillStyle = qgcPal.button
                context.fill()
            }
        } // Canvas - arrowCanvas

        Item {
            id:     dropItemHolderRect
            //color:  qgcPal.button
            //radius: _dropCornerRadius

            Loader {
                id: dropDownLoader
                x:  _dropMargin
                y:  _dropMargin

                Connections {
                    target: dropDownLoader.item

                    onWidthChanged: _calcPositions()
                    onHeightChanged: _calcPositions()
                }
Don Gagne's avatar
Don Gagne committed
            }
        }
    } // Item - dropDownItem
}