Fix keyboard focus behavior. (#36)

Fixes #32.

internal/w32/w32.go

@@ -1,10 +1,11 @@
 package w32
 
 import (
-	"golang.org/x/sys/windows"
 	"syscall"
 	"unicode/utf16"
 	"unsafe"
+
+	"golang.org/x/sys/windows"
 )
 
 var (
@@ -38,6 +39,8 @@ var (
 	User32SetWindowLongPtrW  = user32.NewProc("SetWindowLongPtrW")
 	User32AdjustWindowRect   = user32.NewProc("AdjustWindowRect")
 	User32SetWindowPos       = user32.NewProc("SetWindowPos")
+	User32IsDialogMessage    = user32.NewProc("IsDialogMessage")
+	User32GetAncestor        = user32.NewProc("GetAncestor")
 )
 
 const (
@@ -68,6 +71,12 @@ const (
 	WMApp           = 0x8000
 )
 
+const (
+	GAParent    = 1
+	GARoot      = 2
+	GARootOwner = 3
+)
+
 const (
 	GWLStyle = -16
 )

webview.go

@@ -298,6 +298,11 @@ func (w *webview) Run() {
 		} else if msg.Message == w32.WMQuit {
 			return
 		}
+		r, _, _ := w32.User32GetAncestor.Call(uintptr(msg.Hwnd), w32.GARoot)
+		r, _, _ = w32.User32IsDialogMessage.Call(r, uintptr(unsafe.Pointer(&msg)))
+		if r != 0 {
+			continue
+		}
 		_, _, _ = w32.User32TranslateMessage.Call(uintptr(unsafe.Pointer(&msg)))
 		_, _, _ = w32.User32DispatchMessageW.Call(uintptr(unsafe.Pointer(&msg)))
 	}