feat: Make PgUp and PgDown keys move to the previous/next page (#145)

Author: mlaflamm

docs/usage.md

@@ -11,6 +11,8 @@
 | Ctrl+C | Exit              |
 | F10    | Exit              |
 | ↑↓     | Line Up / Down    |
+| PgUp   | Page Up           |
+| PgDown | Page Down         |
 | Home   | Navigate to Start |
 | End    | Navigate to End   |
 | ?      | Show/Hide help    |

internal/app/lazytable.go

@@ -50,15 +50,19 @@ func (m lazyTableModel) Update(msg tea.Msg) (lazyTableModel, tea.Cmd) {
 	var cmd tea.Cmd
 
 	render := false
+	captureMessage := false
 	switch msg := msg.(type) {
 	case tea.KeyMsg:
-		m, render = m.handleKey(msg, render)
+		m, render, captureMessage = m.handleKey(msg, render)
 
 	case EntriesUpdateMsg:
 		m.entries = msg.Entries
 		render = true
 	}
-	m.table, cmd = m.table.Update(msg)
+
+	if !captureMessage {
+		m.table, cmd = m.table.Update(msg)
+	}
 
 	if m.table.Cursor() != m.lastCursor {
 		render = true
@@ -92,18 +96,20 @@ func (m lazyTableModel) getCellRenderer() func(table.Model, string, table.CellPo
 	}
 }
 
-func (m lazyTableModel) handleKey(msg tea.KeyMsg, render bool) (lazyTableModel, bool) {
+func (m lazyTableModel) handleKey(msg tea.KeyMsg, render bool) (lazyTableModel, bool, bool) {
+	captureMessage := false // when true, the key message must not be forwarded to the inner table
+
 	// toggle the reverse display of items.
 	if key.Matches(msg, m.keys.Reverse) {
 		m.reverse = !m.reverse
 		render = true
 	}
 
-	// this function increases the viewport offset by 1 if possible.  (scrolls down)
-	increaseOffset := func() {
+	// this function increases the viewport offset by n if possible.  (scrolls down)
+	increaseOffset := func(n int) {
 		maxOffset := max(m.entries.Len()-m.table.Height(), 0)
 
-		offset := min(m.offset+1, maxOffset)
+		offset := min(m.offset+n, maxOffset)
 		if offset != m.offset {
 			m.offset = offset
 			render = true
@@ -113,9 +119,9 @@ func (m lazyTableModel) handleKey(msg tea.KeyMsg, render bool) (lazyTableModel,
 		}
 	}
 
-	// this function decreases the viewport offset by 1 if possible.  (scrolls up)
-	decreaseOffset := func() {
-		offset := max(m.offset-1, 0)
+	// this function decreases the viewport offset by n if possible.  (scrolls up)
+	decreaseOffset := func(n int) {
+		offset := max(m.offset-n, 0)
 		if offset != m.offset {
 			m.offset = offset
 			render = true
@@ -131,17 +137,29 @@ func (m lazyTableModel) handleKey(msg tea.KeyMsg, render bool) (lazyTableModel,
 	if key.Matches(msg, m.keys.Down) {
 		m.follow = false
 		if m.table.Cursor()+1 == m.table.Height() {
-			increaseOffset() // move the viewport
+			increaseOffset(1) // move the viewport
 		}
 	}
 
 	if key.Matches(msg, m.keys.Up) {
 		m.follow = false
 		if m.table.Cursor() == 0 {
-			decreaseOffset() // move the viewport
+			decreaseOffset(1) // move the viewport
 		}
 	}
 
+	if key.Matches(msg, m.keys.PageDown) {
+		m.follow = false
+		increaseOffset(m.table.Height() - 1) // move the viewport
+		captureMessage = !m.follow
+	}
+
+	if key.Matches(msg, m.keys.PageUp) {
+		m.follow = false
+		decreaseOffset(m.table.Height() - 1) // move the viewport
+		captureMessage = !m.follow
+	}
+
 	if key.Matches(msg, m.keys.GotoTop) {
 		if m.reverse {
 			// when follow is enabled, rendering will handle setting the offset to the correct value
@@ -164,7 +182,7 @@ func (m lazyTableModel) handleKey(msg tea.KeyMsg, render bool) (lazyTableModel,
 		render = true
 	}
 
-	return m, render
+	return m, render, captureMessage
 }
 
 func (m lazyTableModel) viewPortCursor() int {

internal/app/logstable.go

@@ -32,6 +32,8 @@ func newLogsTableModel(
 	)
 	tableLogs.KeyMap.LineUp = application.keys.Up
 	tableLogs.KeyMap.LineDown = application.keys.Down
+	tableLogs.KeyMap.PageUp = application.keys.PageUp
+	tableLogs.KeyMap.PageDown = application.keys.PageDown
 	tableLogs.KeyMap.GotoBottom = application.keys.GotoBottom
 	tableLogs.KeyMap.GotoTop = application.keys.GotoTop
 

internal/keymap/keymap.go

@@ -11,6 +11,8 @@ type KeyMap struct {
 	Up              key.Binding
 	Reverse         key.Binding
 	Down            key.Binding
+	PageUp          key.Binding
+	PageDown        key.Binding
 	Filter          key.Binding
 	ToggleFullHelp  key.Binding
 	GotoTop         key.Binding
@@ -20,6 +22,7 @@ type KeyMap struct {
 
 // GetDefaultKeys returns default KeyMap.
 func GetDefaultKeys() KeyMap {
+	const spacebar = " "
 	return KeyMap{
 		Exit: key.NewBinding(
 			key.WithKeys("ctrl+c", "f10"),
@@ -48,6 +51,14 @@ func GetDefaultKeys() KeyMap {
 			key.WithKeys("down"),
 			key.WithHelp("↓", "Down"),
 		),
+		PageUp: key.NewBinding(
+			key.WithKeys("pgup"),
+			key.WithHelp("pgup", "page up"),
+		),
+		PageDown: key.NewBinding(
+			key.WithKeys("pgdown", spacebar),
+			key.WithHelp("pgdn", "page down"),
+		),
 		Filter: key.NewBinding(
 			key.WithKeys("f"),
 			key.WithHelp("f", "Filter"),
@@ -69,7 +80,7 @@ func GetDefaultKeys() KeyMap {
 
 func (k KeyMap) ShortHelp() []key.Binding {
 	return []key.Binding{
-		k.Back, k.Open, k.Up, k.Down, k.ToggleFullHelp,
+		k.Back, k.Open, k.Up, k.Down, k.PageUp, k.PageDown, k.ToggleFullHelp,
 	}
 }
 
@@ -78,6 +89,7 @@ func (k KeyMap) FullHelp() [][]key.Binding {
 		{k.Up, k.Down},
 		{k.Back, k.Open},
 		{k.Filter, k.Reverse},
+		{k.PageUp, k.PageDown},
 		{k.GotoTop, k.GotoBottom},
 		{k.ToggleFullHelp, k.Exit},
 	}