Crash when trying to bind Window.height to WebEngineView.contentsSize.height (short code)

  • Hi,

    I use Qt 5.10.1 on up-to-date Windows 10 and the following simple program does not show any window:

    import QtQuick 2.10
    import QtQuick.Window 2.10
    import QtWebEngine 1.5
    Window { id: w
        visible: true
        title: "Test"
        // with this line, the program crashes before showing anything:
        height: v.contentsSize.height
        WebEngineView { id: v
            anchors.left: w.left
            anchors.right: w.right
            onContentsSizeChanged: {
                console.log(contentsSize) // no output if not both width and height properties of the web view are specified
                w.height = contentsSize.height
            // if any of the following 2 lines are omitted, the web view the ":-)" string in the web view does not show up and the window looks empty although anchors.left and anchors.right are set above and the height is set
            // width: 100
            // height: 100
            // The following line crashes the program before showing the window
            // height: v.contentsSize.height
            Component.onCompleted: {

    I specifically want the window to be as high as the web view when its size is not constrained. Relevant documentation link:


  • @alwayslearning
    This seems to be related with a bug when accessing contentsSize too early:

    Apparently, this still doesn't work correctly in Qt 5.10.0, although the bug was considered solved?

    As a check, I tried accessing the property in the onLoadProgressChanged handler:

            onLoadProgressChanged: {
                if (loadProgress===100)

    This works (I tried by setting the url property to a webpage). Maybe as a workaround, you could set your window height in that handler.

  • Lifetime Qt Champion


    The bug report states that 5.10.0 is also affected. It's been solved for 5.9.5 so it will likely be also for the release of 5.11.

Log in to reply