Creating a modal window

[mar1ged]

I need to create a window that can not be put into the background and stays on top of all windows until I close it after a certain button has been clicked.
Normally such behavior is not good style but in this case it is necessary to make sure that I have the full attention of the user because the information displayed in the window is of type "stop the world".
From what I know this would be "modal" or "system modal" but didn't find a way to create such a window with walk.
Is this possible ? It wouldn't matter which API of walk enables me to do this.

[lxn]

You may want to try SetWindowPos from the win package with HWND_TOPMOST for hWndInsertAfter.

[mar1ged]

I tried to follow your suggestion, took the test.go from the readme and attempted to add the SetWindowPos you mentioned. Probably this is due to my limited experience with Go, but I failed to get access to mw.hWnd.
Can you give me one more hint ?

[lpintes]

Use mw.Handle()

[mar1ged]

@lpintes Thanks for your suggestion, but are you sure ? I can't find Handle() in MainWindow.

w := MainWindow{
Title:   "SCREAMO",
...

[lpintes]

Hello,
Do the following:
Declare the variable of the walk.MainWindow type

var mw walk.MainWindow

Then in window declaration, in the MainWindow { ... }, add a line
AssignTo: &mw,

Then later in the code you can use mw.Handle().

[mar1ged]

@lpintes Thanks again, I'm getting closer.

I defined the variable like this (without * the compiler complained):
var mw *walk.MainWindow

When the Run() returns (for which I have to close the window) mw is no longer <nil> but 0 which is because after closing the original Handle() is lost and thus set to 0.
I guess I need to call Run() in a goroutine, but how can I know that walk opened the window and finished setting the handle value ?
Is there perhaps a better approach ?

[lxn]

You should do it similar to the actions example. Switch from calling Run on the declarative.MainWindow, to Create. Then you can do your custom initialization win.SetWindowPos(mw.Handle(), ...) and after that run the message loop via mw.Run.

[mar1ged]

Thanks to @lxn and @lpintes I came up with this solution (based on actions.go, modifications are shown below):

var mw *walk.MainWindow
...
MainWindow{
    AssignTo: &mw,
    Title:    "SCREAMO",
    ...
    },
}.Create()

win.SetWindowPos(mw.Handle(), win.HWND_TOPMOST, -1, -1, -1, -1, win.SWP_NOMOVE|win.SWP_NOREPOSITION|win.SWP_NOSIZE)
mw.Run()