LegendItem.qml Example File

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  import QtQuick 2.1
  import QtQuick.Layouts 1.0
  import QtQuick.Window 2.1
  import QtDataVisualization 1.0

  Rectangle {
      property Theme3D theme
      property Bar3DSeries series
      property point previousSelection

      id: legendItem
      state: "unselected"

      // Workaround for a layout bug that in some situations causes changing from fully opaque color
      // to a transparent one to use black background instead of what is actually under the items.
      // Having the control always slighthly transparent forces the background to be refreshed
      // properly.
      opacity: 0.999

      RowLayout {
          anchors.fill: parent
          spacing: 0
          clip: true
          Item {
              id: markerSpace
              Layout.minimumWidth: 20
              Layout.minimumHeight: 20
              Layout.fillWidth: true
              Layout.fillHeight: true
              Layout.alignment: Qt.AlignVCenter
              Rectangle {
                  x: parent.x + parent.width / 4
                  y: parent.y + parent.height / 4
                  width: parent.width / 2
                  height: width
                  border.color: "black"
                  color: series.baseColor
              }
          }
          Item {
              height: markerSpace.height
              Layout.fillWidth: true
              Layout.fillHeight: true
              Layout.alignment: Qt.AlignVCenter
              Layout.minimumWidth: 100
              Text {
                  anchors.fill: parent
                  text: series.name
                  verticalAlignment: Text.AlignVCenter
                  clip: true
                  color: theme.labelTextColor
                  font: theme.font
              }
          }
      }

      MouseArea {
          id: mouseArea
          anchors.fill: legendItem
          onClicked: {
              if (legendItem.state === "selected") {
                  series.selectedBar = series.invalidSelectionPosition
              } else {
                  series.selectedBar = previousSelection
              }
          }
      }

      Connections {
          target: series
          onSelectedBarChanged: {
              if (position != series.invalidSelectionPosition) {
                  previousSelection = position
              }
          }
      }

      states: [
          State  {
              name: "selected"
              when: series.selectedBar != series.invalidSelectionPosition
              PropertyChanges {
                  target: legendItem
                  color: series.singleHighlightColor
              }
          },
          State  {
              name: "unselected"
              when: series.selectedBar == series.invalidSelectionPosition
              PropertyChanges {
                  target: legendItem
                  color: theme.labelBackgroundColor
              }
          }
      ]
  }