diff options
| -rw-r--r-- | stdwndclass_windows.go | 40 | ||||
| -rw-r--r-- | sysdata_windows.go | 1 | ||||
| -rw-r--r-- | zconstants_windows_386.go | 1 | ||||
| -rw-r--r-- | zconstants_windows_amd64.go | 1 |
4 files changed, 43 insertions, 0 deletions
diff --git a/stdwndclass_windows.go b/stdwndclass_windows.go index 7ec25fb..d32bd8c 100644 --- a/stdwndclass_windows.go +++ b/stdwndclass_windows.go @@ -68,6 +68,43 @@ func storeSysData(hwnd _HWND, uMsg uint32, wParam _WPARAM, lParam _LPARAM) _LRES return defWindowProc(hwnd, uMsg, wParam, lParam) } +var ( + _getFocus = user32.NewProc("GetFocus") + _isChild = user32.NewProc("IsChild") + // _setFocus in area_windows.go +) + +// this is needed to ensure focus is preserved when switching away from and back to our program +// from http://blogs.msdn.com/b/oldnewthing/archive/2014/05/21/10527168.aspx +func (s *sysData) handleFocus(wParam _WPARAM) { + // parameter splitting from Microsoft's windowsx.h + state := uint32(wParam.LOWORD()) // originally UINT + minimized := wParam.HIWORD() != 0 + + if minimized { // don't do anything on minimize + return + } + if state == _WA_INACTIVE { // focusing out + old, _, _ := _getFocus.Call() + if _HWND(old) != _HWND(_NULL) { // if there is one + r1, _, _ := _isChild.Call( + uintptr(s.hwnd), + old) + if r1 != 0 { + s.lastfocus = _HWND(old) +println("s",s.lastfocus) + } + } + } else { // focusing in + if s.lastfocus != _HWND(_NULL) { // if we have one + r1, _, err := _setFocus.Call(uintptr(s.lastfocus)) + if _HWND(r1) == _HWND(_NULL) { + panic(fmt.Errorf("error setting focus to previously focused window on reactivating Window: %v", err)) + } + } + } +} + func stdWndProc(hwnd _HWND, uMsg uint32, wParam _WPARAM, lParam _LPARAM) _LRESULT { s := getSysData(hwnd) if s == nil { // not yet saved @@ -105,6 +142,9 @@ func stdWndProc(hwnd _HWND, uMsg uint32, wParam _WPARAM, lParam _LPARAM) _LRESUL } } return 0 +// case _WM_ACTIVATE: +// s.handleFocus(wParam) +// return 0 case _WM_GETMINMAXINFO: mm := lParam.MINMAXINFO() // ... minimum size diff --git a/sysdata_windows.go b/sysdata_windows.go index 16d625a..021b80a 100644 --- a/sysdata_windows.go +++ b/sysdata_windows.go @@ -21,6 +21,7 @@ type sysData struct { areawidth int areaheight int clickCounter clickCounter + lastfocus _HWND } type classData struct { diff --git a/zconstants_windows_386.go b/zconstants_windows_386.go index 254e6fd..31a92fb 100644 --- a/zconstants_windows_386.go +++ b/zconstants_windows_386.go @@ -129,6 +129,7 @@ const _VK_RWIN = 92 const _VK_SHIFT = 16 const _VK_SUBTRACT = 109 const _VK_UP = 38 +const _WA_INACTIVE = 0 const _WM_ACTIVATE = 6 const _WM_APP = 32768 const _WM_CLOSE = 16 diff --git a/zconstants_windows_amd64.go b/zconstants_windows_amd64.go index ec746c7..4d8e4c4 100644 --- a/zconstants_windows_amd64.go +++ b/zconstants_windows_amd64.go @@ -129,6 +129,7 @@ const _VK_RWIN = 92 const _VK_SHIFT = 16 const _VK_SUBTRACT = 109 const _VK_UP = 38 +const _WA_INACTIVE = 0 const _WM_ACTIVATE = 6 const _WM_APP = 32768 const _WM_CLOSE = 16 |