Always initialize context menu List

Resolves #12

CHANGELOG

@@ -3,6 +3,7 @@ v1.4.6 (WIP)
 - Add Vim-style keybindings to List
 - Fix List not updating selected item before calling selected handlers
 - Do not handle right click on List when there is no context menu
+- Always initialize context menu List
 
 v1.4.5 (2020-04-25)
 - Add multithreading support

contextmenu.go

@@ -18,9 +18,28 @@ type ContextMenu struct {
 
 // NewContextMenu returns a new context menu.
 func NewContextMenu(parent Primitive) *ContextMenu {
-	c := &ContextMenu{parent: parent}
+	return &ContextMenu{
+		parent: parent,
+	}
+}
 
-	return c
+func (c *ContextMenu) initializeList() {
+	if c.list != nil {
+		return
+	}
+
+	c.list = NewList().
+		ShowSecondaryText(false).
+		SetHover(true).
+		SetWrapAround(true)
+	c.list.
+		SetBorder(true).
+		SetBorderPadding(
+			Styles.ContextMenuPaddingTop,
+			Styles.ContextMenuPaddingBottom,
+			Styles.ContextMenuPaddingLeft,
+			Styles.ContextMenuPaddingRight)
+	c.list.showFocus = false
 }
 
 // ContextMenuList returns the underlying List of the context menu.
@@ -28,6 +47,8 @@ func (c *ContextMenu) ContextMenuList() *List {
 	c.l.Lock()
 	defer c.l.Unlock()
 
+	c.initializeList()
+
 	return c.list
 }
 
@@ -37,20 +58,7 @@ func (c *ContextMenu) AddContextItem(text string, shortcut rune, selected func(i
 	c.l.Lock()
 	defer c.l.Unlock()
 
-	if c.list == nil {
-		c.list = NewList().
-			ShowSecondaryText(false).
-			SetHover(true).
-			SetWrapAround(true)
-		c.list.
-			SetBorder(true).
-			SetBorderPadding(
-				Styles.ContextMenuPaddingTop,
-				Styles.ContextMenuPaddingBottom,
-				Styles.ContextMenuPaddingLeft,
-				Styles.ContextMenuPaddingRight)
-		c.list.showFocus = false
-	}
+	c.initializeList()
 
 	c.list.AddItem(text, "", shortcut, c.wrap(selected))
 	if text == "" && shortcut == 0 {
@@ -74,9 +82,9 @@ func (c *ContextMenu) ClearContextMenu() *ContextMenu {
 	c.l.Lock()
 	defer c.l.Unlock()
 
-	if c.list != nil {
-		c.list.Clear()
-	}
+	c.initializeList()
+
+	c.list.Clear()
 
 	return c
 }
@@ -101,8 +109,26 @@ func (c *ContextMenu) ShowContextMenu(item int, x int, y int, setFocus func(Prim
 	c.show(item, x, y, setFocus)
 }
 
+// HideContextMenu hides the context menu.
+func (c *ContextMenu) HideContextMenu(setFocus func(Primitive)) {
+	c.l.Lock()
+	defer c.l.Unlock()
+
+	c.hide(setFocus)
+}
+
+// ContextMenuVisible returns whether or not the context menu is visible.
+func (c *ContextMenu) ContextMenuVisible() bool {
+	c.l.Lock()
+	defer c.l.Unlock()
+
+	return c.open
+}
+
 func (c *ContextMenu) show(item int, x int, y int, setFocus func(Primitive)) {
-	if c.list == nil || len(c.list.items) == 0 {
+	c.initializeList()
+
+	if len(c.list.items) == 0 {
 		return
 	}
 
@@ -139,11 +165,9 @@ func (c *ContextMenu) show(item int, x int, y int, setFocus func(Primitive)) {
 }
 
 func (c *ContextMenu) hide(setFocus func(Primitive)) {
-	c.open = false
+	c.initializeList()
 
-	if c.list == nil {
-		return
-	}
+	c.open = false
 
 	if c.list.HasFocus() {
 		setFocus(c.parent)

list.go

@@ -577,12 +577,12 @@ func (l *List) Focus(delegate func(p Primitive)) {
 
 // HasFocus returns whether or not this primitive has focus.
 func (l *List) HasFocus() bool {
-	l.RLock()
-	defer l.RUnlock()
-
 	if l.ContextMenu.open {
 		return l.ContextMenu.list.HasFocus()
 	}
+
+	l.RLock()
+	defer l.RUnlock()
 	return l.hasFocus
 }
 
@@ -791,13 +791,13 @@ func (l *List) Draw(screen tcell.Screen) {
 
 	// Draw context menu.
 	if hasFocus && l.ContextMenu.open {
-		list := l.ContextMenu.list
+		ctx := l.ContextMenuList()
 
 		x, y, width, height = l.GetInnerRect()
 
 		// What's the longest option text?
 		maxWidth := 0
-		for _, option := range list.items {
+		for _, option := range ctx.items {
 			strWidth := TaggedStringWidth(option.MainText)
 			if option.Shortcut != 0 {
 				strWidth += 4
@@ -807,15 +807,15 @@ func (l *List) Draw(screen tcell.Screen) {
 			}
 		}
 
-		lheight := len(list.items)
+		lheight := len(ctx.items)
 		lwidth := maxWidth
 
 		// Add space for borders
 		lwidth += 2
 		lheight += 2
 
-		lwidth += l.list.paddingLeft + l.list.paddingRight
-		lheight += l.list.paddingTop + l.list.paddingBottom
+		lwidth += ctx.paddingLeft + ctx.paddingRight
+		lheight += ctx.paddingTop + ctx.paddingBottom
 
 		cx, cy := l.ContextMenu.x, l.ContextMenu.y
 		if cx < 0 || cy < 0 {
@@ -834,12 +834,12 @@ func (l *List) Draw(screen tcell.Screen) {
 			lheight = sheight - cy
 		}
 
-		if list.scrollBarVisibility == ScrollBarAlways || (list.scrollBarVisibility == ScrollBarAuto && len(list.items) > lheight) {
+		if ctx.scrollBarVisibility == ScrollBarAlways || (ctx.scrollBarVisibility == ScrollBarAuto && len(ctx.items) > lheight) {
 			lwidth++ // Add space for scroll bar
 		}
 
-		list.SetRect(cx, cy, lwidth, lheight)
-		list.Draw(screen)
+		ctx.SetRect(cx, cy, lwidth, lheight)
+		ctx.Draw(screen)
 	}
 }
 
@@ -1016,8 +1016,8 @@ func (l *List) MouseHandler() func(action MouseAction, event *tcell.EventMouse,
 		l.Lock()
 
 		// Pass events to context menu.
-		if l.ContextMenu.open && l.ContextMenu.list != nil && l.ContextMenu.list.InRect(event.Position()) {
-			defer l.ContextMenu.list.MouseHandler()(action, event, setFocus)
+		if l.ContextMenuVisible() && l.ContextMenuList().InRect(event.Position()) {
+			defer l.ContextMenuList().MouseHandler()(action, event, setFocus)
 			consumed = true
 			l.Unlock()
 			return
@@ -1031,7 +1031,7 @@ func (l *List) MouseHandler() func(action MouseAction, event *tcell.EventMouse,
 		// Process mouse event.
 		switch action {
 		case MouseLeftClick:
-			if l.ContextMenu.open {
+			if l.ContextMenuVisible() {
 				defer l.ContextMenu.hide(setFocus)
 				consumed = true
 				l.Unlock()
@@ -1073,7 +1073,7 @@ func (l *List) MouseHandler() func(action MouseAction, event *tcell.EventMouse,
 				return
 			}
 		case MouseRightDown:
-			if l.ContextMenu.list == nil || len(l.ContextMenu.list.items) == 0 {
+			if len(l.ContextMenuList().items) == 0 {
 				l.Unlock()
 				return
 			}