Enable focus events through configuration by using focus (option) and…

… on-ui-enter/on-ui-exit events.

app.go

@@ -300,6 +300,8 @@ func (app *app) loop() {
 		}()
 	}
 
+	onUiEnter(app)
+
 	for {
 		select {
 		case <-app.quitChan:
@@ -322,6 +324,7 @@ func (app *app) loop() {
 				cmd.eval(app, nil)
 			}
 
+			onUiExit(app)
 			app.quit()
 
 			app.nav.previewChan <- ""
@@ -461,12 +464,14 @@ func (app *app) loop() {
 			app.ui.draw(app.nav)
 		}
 	}
+
 }
 
 func (app *app) runCmdSync(cmd *exec.Cmd, pause_after bool) {
 	app.nav.previewChan <- ""
 	app.nav.dirPreviewChan <- nil
 
+	onUiExit(app)
 	if err := app.ui.suspend(); err != nil {
 		log.Printf("suspend: %s", err)
 	}
@@ -475,6 +480,7 @@ func (app *app) runCmdSync(cmd *exec.Cmd, pause_after bool) {
 			app.quit()
 			os.Exit(3)
 		}
+		onUiEnter(app)
 	}()
 
 	if err := cmd.Run(); err != nil {
@@ -495,6 +501,7 @@ func (app *app) runCmdSync(cmd *exec.Cmd, pause_after bool) {
 //	%       No    No     Yes    Yes     Yes     Statline for input/output
 //	!       Yes   No     Yes    Yes     Yes     Pause and then resume
 //	&       No    Yes    No     No      No      Do nothing
+//	^       No    No     Yes    Yes     Yes     (internal for events)
 func (app *app) runShell(s string, args []string, prefix string) {
 	app.nav.exportFiles()
 	app.ui.exportSizes()
@@ -513,12 +520,17 @@ func (app *app) runShell(s string, args []string, prefix string) {
 	var out io.Reader
 	var err error
 	switch prefix {
-	case "$", "!":
+	case "$", "!", "^":
 		cmd.Stdin = os.Stdin
 		cmd.Stdout = os.Stderr
 		cmd.Stderr = os.Stderr
-
-		app.runCmdSync(cmd, prefix == "!")
+		if prefix != "^" {
+			app.runCmdSync(cmd, prefix == "!")
+		} else {
+			if err := cmd.Run(); err != nil {
+				app.ui.echoerrf("running ^shell: %s", err)
+			}
+		}
 		return
 	}
 

doc.go

@@ -131,6 +131,7 @@ The following options can be used to customize the behavior of lf:
 	errorfmt         string    (default "\033[7;31;47m")
 	filesep          string    (default "\n")
 	findlen          int       (default 1)
+	focus            bool      (default true)
 	globsearch       bool      (default false)
 	hidden           bool      (default false)
 	hiddenfiles      []string  (default '.*')
@@ -208,6 +209,8 @@ The following special shell commands are used to customize the behavior of lf wh
 	pre-cd
 	on-cd
 	on-select
+	on-ui-enter
+	on-ui-exit
 	on-quit
 
 The following commands/keybindings are provided by default:
@@ -743,6 +746,10 @@ File separator used in environment variables 'fs' and 'fx'.
 Number of characters prompted for the find command.
 When this value is set to 0, find command prompts until there is only a single match left.
 
+	focus          bool      (default on)
+
+Focus displays the selection line inversed if enabled. It can be set from a terminal event to indicate if (or which) lf has focus.
+
 	globsearch     bool      (default false)
 
 When this option is enabled, search command patterns are considered as globs, otherwise they are literals.
@@ -1110,6 +1117,14 @@ This shell command can be defined to be executed after changing a directory.
 
 This shell command can be defined to be executed after the selection changes.
 
+	on-ui-enter
+
+This shell command can be defined to be executed when the UI of lf becomes active. This will be triggered after lf starts and when foreground shell commands finish.
+
+	on-ui-exit
+
+This shell command can be defined to be executed when the UI of lf becomes inactive. This will be triggered before lf exits and before starting foreground shell commands.
+
 	on-quit
 
 This shell command can be defined to be executed before quit.

eval.go

@@ -831,6 +831,18 @@ func (e *setExpr) eval(app *app, args []string) {
 		} else {
 			gOpts.tempmarks = "'"
 		}
+	case "focus":
+		gOpts.focus = true
+		app.ui.loadFile(app, true)
+		app.ui.loadFileInfo(app.nav)
+	case "nofocus":
+		gOpts.focus = false
+		app.ui.loadFile(app, true)
+		app.ui.loadFileInfo(app.nav)
+	case "focus!":
+		gOpts.focus = !gOpts.focus
+		app.ui.loadFile(app, true)
+		app.ui.loadFileInfo(app.nav)
 	case "timefmt":
 		gOpts.timefmt = e.val
 	case "truncatechar":
@@ -1157,6 +1169,22 @@ func onSelect(app *app) {
 	}
 }
 
+func onUiEnter(app *app) {
+	if cmd, ok := gOpts.cmds["on-ui-enter"]; ok {
+		ecmd := cmd.(*execExpr)
+		ecmd.prefix = "^"
+		ecmd.eval(app, nil)
+	}
+}
+
+func onUiExit(app *app) {
+	if cmd, ok := gOpts.cmds["on-ui-exit"]; ok {
+		ecmd := cmd.(*execExpr)
+		ecmd.prefix = "^"
+		ecmd.eval(app, nil)
+	}
+}
+
 func splitKeys(s string) (keys []string) {
 	for i := 0; i < len(s); {
 		r, w := utf8.DecodeRuneInString(s[i:])
@@ -2764,6 +2792,9 @@ func (e *execExpr) eval(app *app, args []string) {
 	case "&":
 		log.Printf("shell-async: %s -- %s", e, args)
 		app.runShell(e.value, args, e.prefix)
+	case "^":
+		log.Printf("shell-sync-evt: %s -- %s", e, args)
+		app.runShell(e.value, args, e.prefix)
 	default:
 		log.Printf("evaluating unknown execution prefix: %q", e.prefix)
 	}

lf.1

@@ -150,6 +150,7 @@ The following options can be used to customize the behavior of lf:
     errorfmt         string    (default "\e033[7;31;47m")
     filesep          string    (default "\en")
     findlen          int       (default 1)
+    focus            bool      (default true)
     globsearch       bool      (default false)
     hidden           bool      (default false)
     hiddenfiles      []string  (default '.*')
@@ -231,6 +232,8 @@ The following special shell commands are used to customize the behavior of lf wh
     pre-cd
     on-cd
     on-select
+    on-ui-enter
+    on-ui-exit
     on-quit
 .EE
 .PP
@@ -905,6 +908,12 @@ File separator used in environment variables 'fs' and 'fx'.
 .PP
 Number of characters prompted for the find command. When this value is set to 0, find command prompts until there is only a single match left.
 .PP
+.EX
+    focus          bool      (default on)
+.EE
+.PP
+Focus displays the selection line inversed if enabled. It can be set from a terminal event to indicate if (or which) lf has focus.
+.PP
 .EX
     globsearch     bool      (default false)
 .EE
@@ -1332,6 +1341,18 @@ This shell command can be defined to be executed after changing a directory.
 .PP
 This shell command can be defined to be executed after the selection changes.
 .PP
+.EX
+    on-ui-enter
+.EE
+.PP
+This shell command can be defined to be executed when the UI of lf becomes active. This will be triggered after lf starts and when foreground shell commands finish.
+.PP
+.EX
+    on-ui-exit
+.EE
+.PP
+This shell command can be defined to be executed when the UI of lf becomes inactive. This will be triggered before lf exits and before starting foreground shell commands.
+.PP
 .EX
     on-quit
 .EE

opts.go

@@ -94,6 +94,7 @@ var gOpts struct {
 	tempmarks        string
 	numberfmt        string
 	tagfmt           string
+	focus            bool
 }
 
 var gLocalOpts struct {
@@ -241,6 +242,7 @@ func init() {
 	gOpts.tempmarks = "'"
 	gOpts.numberfmt = "\033[33m"
 	gOpts.tagfmt = "\033[31m"
+	gOpts.focus = true
 
 	gOpts.keys = make(map[string]expr)
 

ui.go

@@ -486,7 +486,7 @@ func (win *win) printDir(screen tcell.Screen, dir *dir, context *dirContext, dir
 		}
 
 		ce := ""
-		if i == dir.pos {
+		if i == dir.pos && gOpts.focus {
 			switch dirStyle.role {
 			case Active:
 				ce = gOpts.cursoractivefmt
@@ -504,7 +504,7 @@ func (win *win) printDir(screen tcell.Screen, dir *dir, context *dirContext, dir
 
 		tag, ok := context.tags[path]
 		if ok {
-			if i == dir.pos {
+			if i == dir.pos && gOpts.focus {
 				win.print(screen, lnwidth+1, i, st, fmt.Sprintf(cursorescapefmt, tag))
 			} else {
 				win.print(screen, lnwidth+1, i, tcell.StyleDefault, fmt.Sprintf(optionToFmtstr(gOpts.tagfmt), tag))
@@ -1449,17 +1449,32 @@ func (ui *ui) readNormalEvent(ev tcell.Event, nav *nav) expr {
 	return nil
 }
 
-func readCmdEvent(ev tcell.Event) expr {
+func (ui *ui) readCmdEvent(ev tcell.Event) expr {
 	switch tev := ev.(type) {
 	case *tcell.EventKey:
 		if tev.Key() == tcell.KeyRune {
 			if tev.Modifiers() == tcell.ModMask(tcell.ModAlt) {
-				val := string([]rune{'<', 'a', '-', tev.Rune(), '>'})
-				if expr, ok := gOpts.cmdkeys[val]; ok {
-					return expr
+				// support multi-key bindings but only for ESC[ at the moment
+				if tev.Rune() == '[' {
+					ui.keyAcc = append(ui.keyAcc, '<', 'a', '-', tev.Rune(), '>')
+				} else {
+					val := string([]rune{'<', 'a', '-', tev.Rune(), '>'})
+					if expr, ok := gOpts.cmdkeys[val]; ok {
+						return expr
+					}
 				}
 			} else {
-				return &callExpr{"cmd-insert", []string{string(tev.Rune())}, 1}
+				// multi-key bindings
+				if ui.keyAcc != nil {
+					ui.keyAcc = append(ui.keyAcc, tev.Rune())
+					val := string(ui.keyAcc)
+					ui.keyAcc = nil
+					if expr, ok := gOpts.cmdkeys[val]; ok {
+						return expr
+					}
+				} else {
+					return &callExpr{"cmd-insert", []string{string(tev.Rune())}, 1}
+				}
 			}
 		} else {
 			val := gKeyVal[tev.Key()]
@@ -1478,7 +1493,7 @@ func (ui *ui) readEvent(ev tcell.Event, nav *nav) expr {
 	}
 
 	if _, ok := ev.(*tcell.EventKey); ok && ui.cmdPrefix != "" {
-		return readCmdEvent(ev)
+		return ui.readCmdEvent(ev)
 	}
 
 	return ui.readNormalEvent(ev, nav)