Qt 5.11 | Qt Quick | Qt Quick Examples - Views | highlightranges.qml Example File

Qt 5.11.3 Reference Documentation

# highlightranges.qml Example File

views/listview/highlightranges.qml

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      import QtQuick 2.0
      import "content"

      Rectangle {
          id: root
          property int current: 0
          property bool increasing: true
          // Example index automation for convenience, disabled on click or tap
          SequentialAnimation {
              id: anim
              loops: -1
              running: true
              ScriptAction {
                  script: if (increasing) {
                              current++;
                              if (current >= aModel.count -1) {
                                  current = aModel.count - 1;
                                  increasing = !increasing;
                              }
                          } else {
                              current--;
                              if (current <= 0) {
                                  current = 0;
                                  increasing = !increasing;
                              }
                          }
              }

              PauseAnimation { duration: 500 }
          }
          MouseArea{
              id: ma
              z: 1
              anchors.fill: parent
              onClicked: { z = 1 - z; if (anim.running) anim.stop(); else anim.restart();}
          }

          width: 320; height: 480

          // This example shows the same model in three different ListView items,
          // with different highlight ranges. The highlight ranges are set by the
          // preferredHighlightBegin and preferredHighlightEnd properties in ListView.
          //
          // The first ListView does not set a highlight range, so its currentItem
          // can move freely within the visible area. If it moves outside the
          // visible area, the view is automatically scrolled to keep the current
          // item visible.
          //
          // The second ListView sets a highlight range which attempts to keep the
          // current item within the bounds of the range. However,
          // items will not scroll beyond the beginning or end of the view,
          // forcing the highlight to move outside the range at the ends.
          //
          // The third ListView sets the highlightRangeMode to StrictlyEnforceRange
          // and sets a range smaller than the height of an item.  This
          // forces the current item to change when the view is flicked,
          // since the highlight is unable to move.
          //
          // All ListViews bind their currentIndex to the root.current property.
          // The first ListView sets root.current whenever its currentIndex changes
          // due to keyboard interaction.
          // Flicking the third ListView with the mouse also changes root.current.
          ListView {
              id: list1
              height: 50; width: parent.width
              model: PetsModel {id: aModel}
              delegate: petDelegate
              orientation: ListView.Horizontal

              highlight: Rectangle { color: "lightsteelblue" }
              currentIndex: root.current
              onCurrentIndexChanged: root.current = currentIndex
              focus: true
          }

          ListView {
              id: list2
              y: 160
              height: 50; width: parent.width
              model: PetsModel {}
              delegate: petDelegate
              orientation: ListView.Horizontal

              highlight: Rectangle { color: "yellow" }
              currentIndex: root.current
              preferredHighlightBegin: 80; preferredHighlightEnd: 220
              highlightRangeMode: ListView.ApplyRange
          }

          ListView {
              id: list3
              y: 320
              height: 50; width: parent.width
              model: PetsModel {}
              delegate: petDelegate
              orientation: ListView.Horizontal

              highlight: Rectangle { color: "yellow" }
              currentIndex: root.current
              onCurrentIndexChanged: root.current = currentIndex
              preferredHighlightBegin: 125; preferredHighlightEnd: 125
              highlightRangeMode: ListView.StrictlyEnforceRange
          }
          // The delegate for each list
          Component {
              id: petDelegate
              Item {
                  width: 160
                  height: column.height
                  Column {
                      id: column
                      Text { text: 'Name: ' + name }
                      Text { text: 'Type: ' + type }
                      Text { text: 'Age: ' + age }
                  }

                  MouseArea {
                      anchors.fill: parent
                      onClicked: root.current = index
                  }
              }
          }
      }