Qt Quick Demo - Maroon in Trouble

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 import QtQuick 2.0
 import "logic.js" as Logic

 Item {
     id: container
     width: 64
     height: 64
     property alias source: img.source
     property int index
     property int row: 0
     property int col: 0
     property int towerType
     property bool canBuild: true
     property Item gameCanvas: parent.parent.parent
     signal clicked()

     Image {
         id: img
         opacity: (canBuild && gameCanvas.coins >= Logic.towerData[towerType-1].cost) ? 1.0 : 0.4
     }
     Text {
         anchors.right: parent.right
         font.pointSize: 14
         font.bold: true
         color: "#ffffff"
         text: Logic.towerData[towerType - 1].cost
     }
     MouseArea {
         anchors.fill: parent
         onClicked: {
             Logic.buildTower(towerType, col, row)
             container.clicked()
         }
     }
     Image {
         visible: col == index && row != 0
         source: "gfx/dialog-pointer.png"
         anchors.top: parent.bottom
         anchors.topMargin: 4
         anchors.horizontalCenter: parent.horizontalCenter
     }
     Image {
         visible: col == index && row == 0
         source: "gfx/dialog-pointer.png"
         rotation: 180
         anchors.bottom: parent.top
         anchors.bottomMargin: 6
         anchors.horizontalCenter: parent.horizontalCenter
     }
 }