✨ Support paging - fixes #19

CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Alt-Left and Alt-Right for history navigation (#23)
 - You can type `..` in the bottom bar to go up a directory in the URL (#21)
 - Error popup for when input string would result in a too long out-of-spec URL (#25)
+- Paging, using <kbd>d</kbd> and <kbd>u</kbd>, as well as <kbd>Page Up</kbd> and <kbd>Page Down</kbd> (#19)
 
 ### Changed
 - Bottom bar now says `URL/Num./Search: ` when space is pressed

display/display.go

@@ -20,7 +20,9 @@ var tabMap = make(map[int]*structs.Page) // Map of tab number to page
 // Holds the actual tab primitives
 var tabViews = make(map[int]*cview.TextView)
 
+// Terminal dimensions
 var termW int
+var termH int
 
 // The user input and URL display bar at the bottom
 var bottomBar = cview.NewInputField().
@@ -69,6 +71,7 @@ var App = cview.NewApplication().
 	SetAfterResizeFunc(func(width int, height int) {
 		// Store for calculations
 		termW = width
+		termH = height
 
 		// Shift new tabs created before app startup, when termW == 0
 		// XXX: This is hacky but works. The biggest issue is that there will sometimes be a tiny flash
@@ -247,6 +250,12 @@ func Init() {
 		case tcell.KeyCtrlD:
 			go addBookmark()
 			return nil
+		case tcell.KeyPgUp:
+			pageUp()
+			return nil
+		case tcell.KeyPgDn:
+			pageDown()
+			return nil
 		case tcell.KeyRune:
 			// Regular key was sent
 			switch string(event.Rune()) {
@@ -271,6 +280,13 @@ func Init() {
 			case "?":
 				Help()
 				return nil
+			case "u":
+				pageUp()
+				return nil
+			case "d":
+				pageDown()
+				return nil
+
 			// Shift+NUMBER keys, for switching to a specific tab
 			case "!":
 				SwitchTab(0)

display/private.go

@@ -17,6 +17,18 @@ import (
 
 // This file contains the functions that aren't part of the public API.
 
+// pageUp scrolls up 75% of the height of the terminal, like Bombadillo.
+func pageUp() {
+	row, col := tabViews[curTab].GetScrollOffset()
+	tabViews[curTab].ScrollTo(row-(termH/4)*3, col)
+}
+
+// pageDown scrolls down 75% of the height of the terminal, like Bombadillo.
+func pageDown() {
+	row, col := tabViews[curTab].GetScrollOffset()
+	tabViews[curTab].ScrollTo(row+(termH/4)*3, col)
+}
+
 func leftMargin() int {
 	return int(float64(termW) * viper.GetFloat64("a-general.left_margin"))
 }