Function NewTreeView

treeview.go:41–100

(parent Container)

}

func NewTreeView(parent Container) (*TreeView, error) {
	tv := new(TreeView)

	if err := InitWidget(
		tv,
		parent,
		"SysTreeView32",
		win.WS_TABSTOP|win.WS_VISIBLE|win.TVS_HASBUTTONS|win.TVS_LINESATROOT|win.TVS_SHOWSELALWAYS|win.TVS_TRACKSELECT,
		win.WS_EX_CLIENTEDGE); err != nil {
		return nil, err
	}

	succeeded := false
	defer func() {
		if !succeeded {
			tv.Dispose()
		}
	}()

	if hr := win.HRESULT(tv.SendMessage(win.TVM_SETEXTENDEDSTYLE, win.TVS_EX_DOUBLEBUFFER, win.TVS_EX_DOUBLEBUFFER)); win.FAILED(hr) {
		return nil, errorFromHRESULT("TVM_SETEXTENDEDSTYLE", hr)
	}

	if err := tv.setTheme("Explorer"); err != nil {
		return nil, err
	}

	tv.GraphicsEffects().Add(InteractionEffect)
	tv.GraphicsEffects().Add(FocusEffect)

	tv.MustRegisterProperty("CurrentItem", NewReadOnlyProperty(
		func() interface{} {
			return tv.CurrentItem()
		},
		tv.CurrentItemChanged()))

	tv.MustRegisterProperty("CurrentItemLevel", NewReadOnlyProperty(
		func() interface{} {
			level := -1
			item := tv.CurrentItem()

			for item != nil {
				level++
				item = item.Parent()
			}

			return level
		},
		tv.CurrentItemChanged()))

	tv.MustRegisterProperty("HasCurrentItem", NewReadOnlyBoolProperty(
		func() bool {
			return tv.CurrentItem() != nil
		},
		tv.CurrentItemChanged()))

	succeeded = true