func NewMainWindow() (*MainWindow, error) {
mw := new(MainWindow)
if err := InitWindow(
mw,
nil,
mainWindowWindowClass,
win.WS_OVERLAPPEDWINDOW,
win.WS_EX_CONTROLPARENT); err != nil {
return nil, err
}
succeeded := false
defer func() {
if !succeeded {
mw.Dispose()
}
}()
mw.SetPersistent(true)
var err error
if mw.menu, err = newMenuBar(); err != nil {
return nil, err
}
if !win.SetMenu(mw.hWnd, mw.menu.hMenu) {
return nil, lastError("SetMenu")
}
if mw.toolBar, err = NewToolBar(mw); err != nil {
return nil, err
}
mw.toolBar.parent = nil
mw.Children().Remove(mw.toolBar)
mw.toolBar.parent = mw
win.SetParent(mw.toolBar.hWnd, mw.hWnd)
if mw.statusBar, err = NewStatusBar(mw); err != nil {
return nil, err
}
mw.statusBar.parent = nil
mw.Children().Remove(mw.statusBar)
mw.statusBar.parent = mw
win.SetParent(mw.statusBar.hWnd, mw.hWnd)
// This forces display of focus rectangles, as soon as the user starts to type.
mw.SendMessage(win.WM_CHANGEUISTATE, win.UIS_INITIALIZE, 0)
succeeded = true
return mw, nil
}
func (tw *TabWidget) onInsertedPage(index int, page *TabPage) (err error) {
item := tw.tcitemFromPage(page)
if idx := int(win.SendMessage(tw.hWndTab, win.TCM_INSERTITEM, uintptr(index), uintptr(unsafe.Pointer(item)))); idx == -1 {
return newError("SendMessage(TCM_INSERTITEM) failed")
}
page.SetVisible(false)
style := uint32(win.GetWindowLong(page.hWnd, win.GWL_STYLE))
if style == 0 {
return lastError("GetWindowLong")
}
style |= win.WS_CHILD
style &^= win.WS_POPUP
win.SetLastError(0)
if win.SetWindowLong(page.hWnd, win.GWL_STYLE, int32(style)) == 0 {
return lastError("SetWindowLong")
}
if win.SetParent(page.hWnd, tw.hWnd) == 0 {
return lastError("SetParent")
}
if tw.pages.Len() == 1 {
page.SetVisible(true)
tw.SetCurrentIndex(0)
}
tw.resizePages()
page.tabWidget = tw
return
}
// InitWidget initializes a Widget.
func InitWidget(widget Widget, parent Window, className string, style, exStyle uint32) error {
if parent == nil {
return newError("parent cannot be nil")
}
if err := InitWindow(widget, parent, className, style|win.WS_CHILD, exStyle); err != nil {
return err
}
if container, ok := parent.(Container); ok {
if container.Children() == nil {
// Required by parents like MainWindow and GroupBox.
if win.SetParent(widget.Handle(), container.Handle()) == 0 {
return lastError("SetParent")
}
} else {
if err := container.Children().Add(widget); err != nil {
return err
}
}
}
return nil
}
// SetParent sets the parent of the WidgetBase and adds the WidgetBase to the
// Children list of the Container.
func (wb *WidgetBase) SetParent(parent Container) (err error) {
if parent == wb.parent {
return nil
}
style := uint32(win.GetWindowLong(wb.hWnd, win.GWL_STYLE))
if style == 0 {
return lastError("GetWindowLong")
}
if parent == nil {
style &^= win.WS_CHILD
style |= win.WS_POPUP
if win.SetParent(wb.hWnd, 0) == 0 {
return lastError("SetParent")
}
win.SetLastError(0)
if win.SetWindowLong(wb.hWnd, win.GWL_STYLE, int32(style)) == 0 {
return lastError("SetWindowLong")
}
} else {
style |= win.WS_CHILD
style &^= win.WS_POPUP
win.SetLastError(0)
if win.SetWindowLong(wb.hWnd, win.GWL_STYLE, int32(style)) == 0 {
return lastError("SetWindowLong")
}
if win.SetParent(wb.hWnd, parent.Handle()) == 0 {
return lastError("SetParent")
}
}
b := wb.Bounds()
if !win.SetWindowPos(
wb.hWnd,
win.HWND_BOTTOM,
int32(b.X),
int32(b.Y),
int32(b.Width),
int32(b.Height),
win.SWP_FRAMECHANGED) {
return lastError("SetWindowPos")
}
oldParent := wb.parent
wb.parent = parent
var oldChildren, newChildren *WidgetList
if oldParent != nil {
oldChildren = oldParent.Children()
}
if parent != nil {
newChildren = parent.Children()
}
if newChildren == oldChildren {
return nil
}
widget := wb.window.(Widget)
if oldChildren != nil {
oldChildren.Remove(widget)
}
if newChildren != nil && !newChildren.containsHandle(wb.hWnd) {
newChildren.Add(widget)
}
return nil
}