Warning, /frameworks/kirigami/src/controls/templates/AbstractApplicationHeader.qml is written in an unsupported language. File is not indexed.

 /*
  *  SPDX-FileCopyrightText: 2015 Marco Martin <mart@kde.org>
  *
  *  SPDX-License-Identifier: LGPL-2.0-or-later
  */
 
 import QtQuick
 import QtQuick.Layouts
 import QtQuick.Controls as QQC2
 import org.kde.kirigami as Kirigami
 import "private"
 
 /**
  * @brief An item that can be used as a title for the application.
  *
  * Scrolling the main page will make it taller or shorter (through the point of going away)
  * It's a behavior similar to the typical mobile web browser addressbar
  * the minimum, preferred and maximum heights of the item can be controlled with
  * * minimumHeight: default is 0, i.e. hidden
  * * preferredHeight: default is Units.gridUnit * 1.6
  * * maximumHeight: default is Units.gridUnit * 3
  *
  * To achieve a titlebar that stays completely fixed just set the 3 sizes as the same
  *
  * @inherit QtQuick.Item
  */
 Item {
     id: root
     z: 90
     property int minimumHeight: 0
     // Use an inline arrow function, referring to an external normal function makes QV4 crash, see https://bugreports.qt.io/browse/QTBUG-119395
     property int preferredHeight: mainItem.children.reduce((accumulator, item) => {
         return Math.max(accumulator, item.implicitHeight);
     }, 0) + topPadding + bottomPadding
     property int maximumHeight: Kirigami.Units.gridUnit * 3
 
     property int position: QQC2.ToolBar.Header
 
     property Kirigami.PageRow pageRow: __appWindow?.pageStack ?? null
     property Kirigami.Page page: pageRow?.currentItem ?? null
 
     default property alias contentItem: mainItem.data
     readonly property int paintedHeight: headerItem.y + headerItem.height - 1
 
     property int leftPadding: 0
     property int topPadding: 0
     property int rightPadding: 0
     property int bottomPadding: 0
     property bool separatorVisible: true
 
     /**
      * This property specifies whether the header should be pushed back when
      * scrolling using the touch screen.
      */
     property bool hideWhenTouchScrolling: root.pageRow?.globalToolBar.hideWhenTouchScrolling ?? false
 
     LayoutMirroring.enabled: Qt.application.layoutDirection === Qt.RightToLeft
     LayoutMirroring.childrenInherit: true
 
     Kirigami.Theme.inherit: true
 
     // FIXME: remove
     property QtObject __appWindow: typeof applicationWindow !== "undefined" ? applicationWindow() : null
     implicitHeight: preferredHeight
     height: Layout.preferredHeight
 
     /**
      * @brief This property holds the background item.
      * @note the background will be automatically sized to fill the whole control
      */
     property Item background
 
     onBackgroundChanged: {
         background.z = -1;
         background.parent = headerItem;
         background.anchors.fill = headerItem;
     }
 
     Component.onCompleted: AppHeaderSizeGroup.items.push(this)
 
     onMinimumHeightChanged: implicitHeight = preferredHeight;
     onPreferredHeightChanged: implicitHeight = preferredHeight;
 
     opacity: height > 0 ? 1 : 0
 
     NumberAnimation {
         id: heightAnim
         target: root
         property: "implicitHeight"
         duration: Kirigami.Units.longDuration
         easing.type: Easing.InOutQuad
     }
 
     Connections {
         target: root.__appWindow
 
         function onControlsVisibleChanged() {
             heightAnim.from = root.implicitHeight;
             heightAnim.to = root.__appWindow.controlsVisible ? root.preferredHeight : 0;
             heightAnim.restart();
         }
     }
 
     Connections {
         target: root.page?.Kirigami.ColumnView ?? null
 
         function onScrollIntention(event) {
             headerItem.scrollIntentHandler(event);
         }
     }
 
     Item {
         id: headerItem
         anchors {
             left: parent.left
             right: parent.right
             bottom: !Kirigami.Settings.isMobile || root.position === QQC2.ToolBar.Header ? parent.bottom : undefined
             top: !Kirigami.Settings.isMobile || root.position === QQC2.ToolBar.Footer ? parent.top : undefined
         }
 
         height: Math.max(root.height, root.minimumHeight > 0 ? root.minimumHeight : root.preferredHeight)
 
         function scrollIntentHandler(event) {
             if (!root.hideWhenTouchScrolling) {
                 return
             }
 
             if (root.pageRow
                 && root.pageRow.globalToolBar.actualStyle !== Kirigami.ApplicationHeaderStyle.Breadcrumb) {
                 return;
             }
             if (!root.page.flickable || (root.page.flickable.atYBeginning && root.page.flickable.atYEnd)) {
                 return;
             }
 
             root.implicitHeight = Math.max(0, Math.min(root.preferredHeight, root.implicitHeight + event.delta.y))
             event.accepted = root.implicitHeight > 0 && root.implicitHeight < root.preferredHeight;
             slideResetTimer.restart();
             if ((root.page.flickable instanceof ListView) && root.page.flickable.verticalLayoutDirection === ListView.BottomToTop) {
                 root.page.flickable.contentY -= event.delta.y;
             }
         }
 
         Connections {
             target: root.page?.globalToolBarItem ?? null
             enabled: target
             function onImplicitHeightChanged() {
                 root.implicitHeight = root.page.globalToolBarItem.implicitHeight;
             }
         }
 
         Timer {
            id: slideResetTimer
            interval: 500
            onTriggered: {
                 if ((root.pageRow?.wideMode ?? (root.__appWindow?.wideScreen ?? false)) || !Kirigami.Settings.isMobile) {
                     return;
                 }
                 if (root.height > root.minimumHeight + (root.preferredHeight - root.minimumHeight) / 2) {
                     heightAnim.to = root.preferredHeight;
                 } else {
                     heightAnim.to = root.minimumHeight;
                 }
                 heightAnim.from = root.implicitHeight
                 heightAnim.restart();
             }
         }
 
         Connections {
             target: pageRow
             function onCurrentItemChanged() {
                 if (!root.page) {
                     return;
                 }
 
                 heightAnim.from = root.implicitHeight;
                 heightAnim.to = root.preferredHeight;
 
                 heightAnim.restart();
             }
         }
 
         Item {
             id: mainItem
             clip: childrenRect.width > width
 
             onChildrenChanged: {
                 for (const child of children) {
                     child.anchors.verticalCenter = verticalCenter;
                 }
             }
 
             anchors {
                 fill: parent
                 topMargin: root.topPadding
                 leftMargin: root.leftPadding
                 rightMargin: root.rightPadding
                 bottomMargin: root.bottomPadding
             }
         }
     }
 }