Buffers ?!

wdgt_simple_list.go

@@ -72,16 +72,36 @@ func (w *SimpleList) Init(id string, style tcell.Style) {
 			}
 			return false
 		},
+		tcell.KeyPgDn: func(_ *tcell.EventKey) bool { return w.PageDn() },
+		tcell.KeyPgUp: func(_ *tcell.EventKey) bool { return w.PageUp() },
 	})
 	w.keyMap.AddRune('j', func(ev *tcell.EventKey) bool {
-		if w.vimMode {
-			return w.MoveDown()
+		if !w.vimMode {
+			return false
+		}
+		return w.MoveDown()
+	})
+	w.keyMap.AddRune('k', func(ev *tcell.EventKey) bool {
+		if !w.vimMode {
+			return false
+		}
+		return w.MoveUp()
+	})
+	w.keyMap.AddRune('b', func(ev *tcell.EventKey) bool {
+		if !w.vimMode {
+			return false
+		}
+		if ev.Modifiers()&tcell.ModCtrl != 0 {
+			return w.PageUp()
 		}
 		return false
 	})
-	w.keyMap.AddRune('k', func(ev *tcell.EventKey) bool {
-		if w.vimMode {
-			return w.MoveUp()
+	w.keyMap.AddRune('f', func(ev *tcell.EventKey) bool {
+		if !w.vimMode {
+			return false
+		}
+		if ev.Modifiers()&tcell.ModCtrl != 0 {
+			return w.PageDn()
 		}
 		return false
 	})
@@ -89,6 +109,7 @@ func (w *SimpleList) Init(id string, style tcell.Style) {
 	w.itemsStyle = make(map[int]tcell.Style)
 	w.focusable = true
 }
+
 func (w *SimpleList) Id() string                         { return w.id }
 func (w *SimpleList) HandleResize(ev *tcell.EventResize) { w.w, w.h = ev.Size() }
 
@@ -134,7 +155,33 @@ func (w *SimpleList) Draw(screen tcell.Screen) {
 		}
 	}
 	x, y = x+1, y+1
-	for i := range w.list {
+	h := w.h - brdSz
+	ln := len(w.list)
+	st, ed := 0, ln-1
+	if ln == 0 {
+		return
+	}
+	if ln > w.h-2 {
+		mid := h / 2
+		if w.cursor < mid {
+			// List needs to begin at 0
+			ed = h + 1
+		} else if w.cursor > ln-mid {
+			// List needs to begin at ln-h
+			st = ln - h + 1
+		} else {
+			st = w.cursor - mid
+			ed = st + h + 1
+		}
+	}
+	// ed cannot be higher than ln-1
+	if st < 0 {
+		st = 0
+	}
+	if ed > ln-1 {
+		ed = ln - 1
+	}
+	for i := st; i <= ed; i++ {
 		rev := false
 		if i == w.cursor {
 			rev = true
@@ -215,7 +262,7 @@ func (w *SimpleList) MoveUp() bool {
 }
 
 func (w *SimpleList) MoveDown() bool {
-	if w.cursor < len(w.list)-1 {
+	if w.cursor <= len(w.list)-2 {
 		w.cursor++
 		if w.onChange != nil {
 			w.onChange(w.cursor, w.list[w.cursor])
@@ -230,6 +277,28 @@ func (w *SimpleList) MoveDown() bool {
 	}
 	return false
 }
+
+func (w *SimpleList) PageUp() bool {
+	w.cursor -= w.h
+	if len(w.border) > 0 {
+		w.cursor += 2
+	}
+	if w.cursor < 0 {
+		w.cursor = 0
+	}
+	return true
+}
+
+func (w *SimpleList) PageDn() bool {
+	w.cursor += w.h
+	if len(w.border) > 0 {
+		w.cursor -= 2
+	}
+	if w.cursor > len(w.list)-2 {
+		w.cursor = len(w.list) - 2
+	}
+	return true
+}
 func (w *SimpleList) SetTitle(ttl string) { w.title = ttl }
 func (w *SimpleList) SetList(l []string)  { w.list = l }
 func (w *SimpleList) Clear() {
@@ -238,7 +307,11 @@ func (w *SimpleList) Clear() {
 		delete(w.itemsStyle, k)
 	}
 }
-func (w *SimpleList) Add(l string) { w.list = append(w.list, l) }
+
+func (w *SimpleList) Add(l string) {
+	w.list = append(w.list, l)
+}
+
 func (w *SimpleList) Remove(l string) {
 	var idx int
 	var found bool
@@ -289,4 +362,6 @@ func (w *SimpleList) Log(txt string, args ...any) {
 
 func (w *SimpleList) SetOnChange(c func(int, string) bool) { w.onChange = c }
 
+func (w *SimpleList) GetSelectedItem() string               { return w.list[w.cursor] }
+func (w *SimpleList) GetAllItems() []string                 { return w.list }
 func (w *SimpleList) GetAllItemStyles() map[int]tcell.Style { return w.itemsStyle }