Golang中的EnumChildWindows回调函数

Question

Using package lxn/win in main:

win.EnumChildWindows(hw, printme, 0)

Then after main:

func printme(HWND win.HANDLE, LPARAM uintptr) { //HWND hwnd, LPARAM lParam
    spew.Dump(HWND)
}

I get:

.\test.go:40: cannot use printme (type func(win.HANDLE, uintptr)) as type uintptr in argument to win.EnumChildWindows

error:exit status 2

I don't understand the error message.

Answer 1

I made it work with:

win.EnumChildWindows(hwnd, syscall.NewCallback(printme), 0)

func printme(hwnd uintptr, lParam uintptr) uintptr {
    spew.Dump(hwnd)
    fmt.Printf("getWindowText: '%s'
", getWindowText(hwnd))
    return 1 // true to continue
}

See lxn/win issue 19:

The callback signature is wrong: it has to return a value of type int32 (C BOOL) that is nonzero if the function should continue enumeration.
See MSDN.

For example, it could be:

func printme(hwnd uintptr, lParam uintptr) int32 {
    spew.Dump(hwnd)
    return 1 // true to continue
}