Is it possible to host a QT application into a WPF application?

Question

I'm trying to create WPF GUI application to host an already exist QT GUI application as part of the main UI.

The QT application don't need to deal with mouse/keyboard input.

I've tried approach mentioned in this SO Post. Seems all those approach does not work for a QT application.

score 1 · Answer 1 · answered Oct 17 '16 at 08:25

I don't know if it's a right thing to do, but that's what I used some times to embedd other apps (found on the internet):

public partial class MainWindow : Window
{
private Process _process;

[DllImport("user32.dll")]
private static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);

[DllImport("user32.dll", SetLastError = true)]
private static extern int GetWindowLong(IntPtr hWnd, int nIndex);

[DllImport("user32")]
private static extern IntPtr SetParent(IntPtr hWnd, IntPtr hWndParent);

[DllImport("user32")]
private static extern bool SetWindowPos(IntPtr hWnd, IntPtr hWndInsertAfter, int X, int Y, int cx, int cy, int uFlags);

private const int SWP_NOZORDER = 0x0004;
private const int SWP_NOACTIVATE = 0x0010;
private const int GWL_STYLE = -16;
private const int WS_CAPTION = 0x00C00000;
private const int WS_THICKFRAME = 0x00040000;
const string patran = "patran";
public MainWindow()
{
    InitializeComponent();

    Loaded += (s, e) => LaunchChildProcess();
}

private void LaunchChildProcess()
{
    _process = Process.Start("/path/to/QtExecutable.exe");
    _process.WaitForInputIdle();

    var helper = new WindowInteropHelper(this);

    SetParent(_process.MainWindowHandle, helper.Handle);

    // remove control box
    int style = GetWindowLong(_process.MainWindowHandle, GWL_STYLE);
    style = style & ~WS_CAPTION & ~WS_THICKFRAME;
    SetWindowLong(_process.MainWindowHandle, GWL_STYLE, style);
    // resize embedded application & refresh
    ResizeEmbeddedApp();
}

private void ResizeEmbeddedApp()
{
    if (_process == null)
        return;
    SetWindowPos(_process.MainWindowHandle, IntPtr.Zero, 0, 0, (int)ActualWidth, (int)ActualHeight, SWP_NOZORDER | SWP_NOACTIVATE);
}

protected override Size MeasureOverride(Size availableSize)
{
    Size size = base.MeasureOverride(availableSize);
    ResizeEmbeddedApp();
    return size;
}

Just modify this skeleton to your necessities. Let me know if it works.

Thanks Luca, it works for me, although there is still some minor issues. I'll accept it as answer and give the awards later if there is no better solution. — ricky, Oct 17 '16 at 13:35
It's not "found on the internet", it's found on SO here: http://stackoverflow.com/questions/5028598/hosting-external-app-in-wpf-window — Simon Mourier, Oct 24 '16 at 06:25
@SimonMourier well I actually didn't know it was there. I found it on the Internet (possibly that answer) a year ago and I just copied the code I had on a project. Sorry — Luca Angioloni, Oct 25 '16 at 06:26
@SimonMourier to be fair, I believe this answer is somewhat different from the SO post you mentioned. Because I have tried that solution, but failed to make it work with QT app. — ricky, Oct 31 '16 at 02:03
@LucaAngioloni have you got the bounty? I've been lost access to SO last fortnight because the GFW... — ricky, Oct 31 '16 at 02:10
@LucaAngioloni I'm so sorry. It's my bad. It has been subtracted from my score... — ricky, Oct 31 '16 at 02:27
@ricky - never said it was the exact same answer, but one should cite his/her source, and for example, explain why it does not work, explain what was changed to make it work, etc. — Simon Mourier, Oct 31 '16 at 06:50

ctc chen · Answer 2 · 2016-10-31T09:05:18.183

0

Yes. It is possible. A very simple way for your quick start without the effort of coding.

Check this link: Hosting EXE Applications in a WPF Window Application (http://www.codeproject.com/Tips/673701/Hosting-EXE-Applications-in-a-WPF-Window-Applicati). Download the project. Find "notepad.exe" in the project and replace it with the file name of your QT application. Just a remind: for the WPF exe to launch the QT application, you may need to take care of the environment variables required by QT.

What it looks like:

edited Oct 31 '16 at 09:05

answered Oct 24 '16 at 06:59

ctc chen

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I tried this before ask this question. And it seems not work with a QT app – ricky Oct 31 '16 at 02:02
in this file: TestWpfAppControl\MainWindow.xaml.cs, register the environment variables required by your QT. For my case, I put all my QT executables under the folder of my WPF exe. And I modify the MainWindow.xaml.cs file as:appControl.ExeName = "myQT.exe"; Environment.SetEnvironmentVariable("PATH", "bin"); – ctc chen Oct 31 '16 at 08:32

Is it possible to host a QT application into a WPF application?

2 Answers2