highlightranges.qml Example File | Qt Quick 5.12.8

Qt 5.12 | Qt Quick | Qt Quick Examples - Views | highlightranges.qml Example File

Qt 5.12.8 Reference Documentation

# highlightranges.qml Example File

views/listview/highlightranges.qml

      /****************************************************************************
      **
      ** Copyright (C) 2017 The Qt Company Ltd.
      ** Contact: https://www.qt.io/licensing/
      **
      ** This file is part of the examples of the Qt Toolkit.
      **
      ** $QT_BEGIN_LICENSE:BSD$
      ** Commercial License Usage
      ** Licensees holding valid commercial Qt licenses may use this file in
      ** accordance with the commercial license agreement provided with the
      ** Software or, alternatively, in accordance with the terms contained in
      ** a written agreement between you and The Qt Company. For licensing terms
      ** and conditions see https://www.qt.io/terms-conditions. For further
      ** information use the contact form at https://www.qt.io/contact-us.
      **
      ** BSD License Usage
      ** Alternatively, you may use this file under the terms of the BSD license
      ** as follows:
      **
      ** "Redistribution and use in source and binary forms, with or without
      ** modification, are permitted provided that the following conditions are
      ** met:
      **   * Redistributions of source code must retain the above copyright
      **     notice, this list of conditions and the following disclaimer.
      **   * Redistributions in binary form must reproduce the above copyright
      **     notice, this list of conditions and the following disclaimer in
      **     the documentation and/or other materials provided with the
      **     distribution.
      **   * Neither the name of The Qt Company Ltd nor the names of its
      **     contributors may be used to endorse or promote products derived
      **     from this software without specific prior written permission.
      **
      **
      ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
      ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
      ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
      ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
      ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
      ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
      ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
      ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
      ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
      ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
      ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
      **
      ** $QT_END_LICENSE$
      **
      ****************************************************************************/

      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
                  }
              }
          }
      }