diff options
Diffstat (limited to 'area_windows.go')
| -rw-r--r-- | area_windows.go | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/area_windows.go b/area_windows.go index 33692fb..4b4eedc 100644 --- a/area_windows.go +++ b/area_windows.go @@ -208,7 +208,30 @@ func scrollArea(hwnd _HWND, wparam _WPARAM, which uintptr) { return } - // TODO scroll + delta := -(newpos - si.nPos) // negative because ScrollWindowEx() scrolls in the opposite direction + dx := delta + dy := int32(0) + if which == uintptr(_SB_VERT) { + dx = int32(0) + dy = delta + } + r1, _, err = _scrollWindowEx.Call( + uintptr(hwnd), + uintptr(dx), + uintptr(dy), + uintptr(0), // these four change what is scrolled and record info about the scroll; we're scrolling the whole client area and don't care about the returned information here + uintptr(0), + uintptr(0), + uintptr(0), + // TODO also SW_ERASE? or will the GetUpdateRect() call handle it? + uintptr(_SW_INVALIDATE)) // mark the remaining rect as needing redraw... + if r1 == _ERROR { // failure + panic(fmt.Errorf("error scrolling Area: %v", err)) + } + r1, _, err = _updateWindow.Call(uintptr(hwnd)) // ...and redraw it + if r1 == 0 { // failure + panic(fmt.Errorf("error updating Area after scrolling: %v", err)) + } // we actually have to commit the change back to the scrollbar; otherwise the scroll position will merely reset itself si.cbSize = uint32(unsafe.Sizeof(si)) |