Viewport now has customizable keybindings

viewport/keymap.go

@@ -0,0 +1,42 @@
+package viewport
+
+import "github.com/charmbracelet/bubbles/key"
+
+const spacebar = " "
+
+// KeyMap defines the keybindings for the viewport. Note that you don't
+// necessary need to use keybindings at all; the viewport can be controlled
+// programmatically with methods like Model.LineDown(1). See the GoDocs for
+// details.
+type KeyMap struct {
+	PageDown     key.Binding
+	PageUp       key.Binding
+	HalfPageUp   key.Binding
+	HalfPageDown key.Binding
+	Down         key.Binding
+	Up           key.Binding
+}
+
+// DefaultKeyMap returns a set of pager-like default keybindings.
+func DefaultKeyMap() KeyMap {
+	return KeyMap{
+		PageDown: key.NewBinding(
+			key.WithKeys("pgdown", spacebar, "f"),
+		),
+		PageUp: key.NewBinding(
+			key.WithKeys("pgup", "b"),
+		),
+		HalfPageUp: key.NewBinding(
+			key.WithKeys("u", "ctrl+u"),
+		),
+		HalfPageDown: key.NewBinding(
+			key.WithKeys("d", "ctrl+d"),
+		),
+		Up: key.NewBinding(
+			key.WithKeys("up", "k"),
+		),
+		Down: key.NewBinding(
+			key.WithKeys("down", "j"),
+		),
+	}
+}