QMLProfiler 中的 QML Listview 报告两次委托创建

Question

这是一个只有 10 个项目的简单 ListView。当我运行此应用程序的 QMLProfiler 时，统计信息显示创建委托的调用次数是两倍。有人可以解释这是这种行为吗？

import QtQuick 2.12
import QtQuick.Window 2.12

Window {
    visible: true
    width: 640
    height: 480
    title: qsTr("Hello World")
    ListView{
        anchors.fill: parent
        model: 10
        delegate: Rectangle{
            width: parent.width
            height: 60
            Text {
                id: name
                text: qsTr("Item is ") + index
            }
        }
    }
}

Answer 1

答案可以从 Qt 错误报告中找到 QML Profiler 显示双倍数量的 Repeater delegate Create 调用告诉以下内容：

Object creation typically happens in two stages, which are counted separately in the profiler.

Each object creation involves one creation phase and one callback to componentComplete(). Those are tracked separately.

QMLProfiler 中的 QML Listview 报告两次委托创建

QML Listview in QMLProfiler reporting twice delegate creation

qt

listview

qml

qt5