Skip to content
DropButton.qml 9.52 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

    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

    // Set up ExclusiveGroup support. We use the checked property to drive visibility of drop down.

    property bool checked: false
    property ExclusiveGroup exclusiveGroup: null

    onExclusiveGroupChanged: {
        if (exclusiveGroup) {
            exclusiveGroup.bindCheckable(_root)
        }
    }

    function hideDropDown() {
        checked = false
    }
Don Gagne's avatar
Don Gagne committed

    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:    checked
        onClicked:  {
            checked = false
            _root.clicked()
        }
Don Gagne's avatar
Don Gagne committed
    }

    // Button
    Rectangle {
Don Gagne's avatar
Don Gagne committed
        anchors.fill:   parent
        radius:         width / 2
        border.width:   2
        border.color:   "white"
        opacity:        checked ? 0.95 : 0.65
        color:          checked ? qgcPal.mapButtonHighlight : qgcPal.mapButton

        Image {
            id:             button
            anchors.fill:   parent
            fillMode:       Image.PreserveAspectFit
            mipmap:         true
            smooth:         true
            MouseArea {
                anchors.fill: parent
                onClicked:  {
                    checked = !checked
                    _root.clicked()
                }
            }
        } // Image - button
    }
Don Gagne's avatar
Don Gagne committed

    Item {
        id:         dropDownItem
        visible:    checked
        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
}