Refactor filter editing input handling.

Only swallow events that are explicitly handled by the editor. Fall
through to the default event handling for all other events.

Also, cancel editing on <Escape> and fix README file formatting.

README.md

@@ -73,7 +73,7 @@ snap connect gotop-cjbassi:system-observe
 - Quit: `q` or `<C-c>`
 - Process navigation:
   - `k` and `<Up>`: up
-  - `j` and `<Down`: down
+  - `j` and `<Down>`: down
   - `<C-u>`: half page up
   - `<C-d>`: half page down
   - `<C-b>`: full page up
@@ -88,10 +88,10 @@ snap connect gotop-cjbassi:system-observe
   - `m`: Mem
   - `p`: PID
 - Process filtering:
-  - /: start editing filter
+  - `/`: start editing filter
 	- (while editing):
-		- <Enter> accept filter
-		- <C-c>: clear filter
+		- `<Enter>` accept filter
+		- `<C-c>` and `<Escape>`: clear filter
 - CPU and Mem graph scaling:
   - `h`: scale in
   - `l`: scale out

main.go

@@ -274,6 +274,33 @@ func initWidgets() {
 	}
 }
 
+// handleEditFilterEvents handles events while editing the proc filter.
+// Returns true if the event was handled.
+func handleEditFilterEvents(e ui.Event) bool {
+	if utf8.RuneCountInString(e.ID) == 1 {
+		proc.SetFilter(proc.Filter() + e.ID)
+		ui.Render(proc)
+		return true
+	}
+	switch e.ID {
+	case "<C-c>", "<Escape>":
+		proc.SetFilter("")
+		proc.SetEditingFilter(false)
+		ui.Render(proc)
+	case "<Enter>":
+		proc.SetEditingFilter(false)
+		ui.Render(proc)
+	case "<Backspace>":
+		if filter := proc.Filter(); filter != "" {
+			proc.SetFilter(filter[:len(filter)-1])
+		}
+		ui.Render(proc)
+	default:
+		return false
+	}
+	return true
+}
+
 func eventLoop() {
 	drawTicker := time.NewTicker(updateInterval).C
 
@@ -297,8 +324,16 @@ func eventLoop() {
 				}
 			}
 		case e := <-uiEvents:
-			// Handle resize event always.
-			if e.ID == "<Resize>" {
+
+			if proc.EditingFilter() && handleEditFilterEvents(e) {
+				break
+			}
+			switch e.ID {
+			case "q", "<C-c>":
+				return
+			case "?":
+				helpVisible = !helpVisible
+			case "<Resize>":
 				payload := e.Payload.(ui.Resize)
 				termWidth, termHeight := payload.Width, payload.Height
 				if statusbar {
@@ -309,55 +344,23 @@ func eventLoop() {
 				}
 				help.Resize(payload.Width, payload.Height)
 				ui.Clear()
-
-				if helpVisible {
-					ui.Render(help)
-				} else {
-					ui.Render(grid)
-					if statusbar {
-						ui.Render(bar)
-					}
-				}
 			}
 
-			if proc.EditingFilter() {
-				if utf8.RuneCountInString(e.ID) == 1 {
-					proc.SetFilter(proc.Filter() + e.ID)
-					ui.Render(proc)
-				}
+			if helpVisible {
 				switch e.ID {
-				case "<C-c>":
-					proc.SetFilter("")
-					proc.SetEditingFilter(false)
-					ui.Render(proc)
-				case "<Enter>":
-					proc.SetEditingFilter(false)
-					ui.Render(proc)
-				case "<Backspace>":
-					if filter := proc.Filter(); filter != "" {
-						proc.SetFilter(filter[:len(filter)-1])
-					}
-					ui.Render(proc)
-				}
-			} else if helpVisible {
-				switch e.ID {
-				case "q", "<C-c>":
-					return
 				case "?":
-					helpVisible = false
-					ui.Render(grid)
+					ui.Clear()
+					ui.Render(help)
 				case "<Escape>":
 					helpVisible = false
 					ui.Render(grid)
+				case "<Resize>":
+					ui.Render(help)
 				}
 			} else {
 				switch e.ID {
-				case "q", "<C-c>":
-					return
 				case "?":
-					helpVisible = true
-					ui.Clear()
-					ui.Render(help)
+					ui.Render(grid)
 				case "h":
 					graphHorizontalScale += graphHorizontalScaleDelta
 					cpu.HorizontalScale = graphHorizontalScale
@@ -370,6 +373,11 @@ func eventLoop() {
 						mem.HorizontalScale = graphHorizontalScale
 						ui.Render(cpu, mem)
 					}
+				case "<Resize>":
+					ui.Render(grid)
+					if statusbar {
+						ui.Render(bar)
+					}
 				case "<MouseLeft>":
 					payload := e.Payload.(ui.Mouse)
 					proc.HandleClick(payload.X, payload.Y)
@@ -414,7 +422,6 @@ func eventLoop() {
 					proc.ChangeProcSortMethod(w.ProcSortMethod(e.ID))
 					ui.Render(proc)
 				case "/":
-					proc.SetFilter("")
 					proc.SetEditingFilter(true)
 					ui.Render(proc)
 				}

src/widgets/help.go

@@ -33,7 +33,7 @@ Process filtering:
   - /: start editing filter
   - (while editing):
     - <Enter>: accept filter
-    - <C-c> clear filter
+    - <C-c> and <Escape>: clear filter
 
 CPU and Mem graph scaling:
   - h: scale in