<![CDATA[lambda expression capture]]>Hi,

is there a way to do this??

connect(this, &MainWindow::loadFile, [viewer](QString value) {viewer->m_dataEngine->loadFile(value); });

I'm in the MainWindow class and want to connect the loadFile signal from MainWindow with the loadFile function from GeometryEngine that is member of viewer.

I thought i could make a lambda expression in viewer, but viewer does not hold an instance of MainWindow. So i hoped that there is a way to make it from MainWindow.

]]>https://forum.qt.io/topic/75607/lambda-expression-captureRSS for NodeFri, 10 Apr 2026 06:32:50 GMTSun, 29 Jan 2017 13:56:39 GMT60<![CDATA[Reply to lambda expression capture on Mon, 30 Jan 2017 05:55:16 GMT]]>@QT-static-prgm Did you try it?
If viewer is a member variable of MainWindow you can do it like this:

connect(this, &MainWindow::loadFile, [this](QString value) {viewer->m_dataEngine->loadFile(value); });

But as @SGaist said it would be better to implement a slot in Viewer.
MainWindow should not care/know about Viewer internals like m_dataEngine.

]]>https://forum.qt.io/post/372347https://forum.qt.io/post/372347Mon, 30 Jan 2017 05:55:16 GMT<![CDATA[Reply to lambda expression capture on Sun, 29 Jan 2017 18:21:25 GMT]]>Hi,

The clean way here would be to add a slot to your viewer class that will call whatever needed. The internals of that viewer class is of no concern to MainWindow.

]]>https://forum.qt.io/post/372289https://forum.qt.io/post/372289Sun, 29 Jan 2017 18:21:25 GMT