Fix app UI latency due to MethodChannels by adding timeStamps

brandonp2412 · Mar 9, 2024 · 0508543 · 0508543
1 parent abf49c7
commit 0508543
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Showing 7 changed files with 77 additions and 38 deletions.
diff --git a/android/app/src/main/kotlin/com/presley/flexify/MainActivity.kt b/android/app/src/main/kotlin/com/presley/flexify/MainActivity.kt
@@ -104,9 +104,8 @@ class MainActivity : FlutterActivity() {
     private val tickReceiver =
         object : BroadcastReceiver() {
             override fun onReceive(context: Context, intent: Intent) {
-                val secondsLeft = intent.getIntExtra("secondsLeft", 0)
-                val secondsTotal = intent.getIntExtra("secondsTotal", 1)
-                channel?.invokeMethod("tick", intArrayOf(secondsLeft, secondsTotal))
+                val result = timerService?.timer?.generateMethodChannelPayload()
+                channel?.invokeMethod("tick", result)
             }
         }
 

diff --git a/android/app/src/main/kotlin/com/presley/flexify/Timer.kt b/android/app/src/main/kotlin/com/presley/flexify/Timer.kt
@@ -79,6 +79,14 @@ class Timer(private var msTimerDuration: Long) {
         return true
     }
 
+    fun generateMethodChannelPayload(): LongArray  {
+        return longArrayOf(
+            totalTimerDuration,
+            totalTimerDuration - getRemainingMillis(),
+            java.lang.System.currentTimeMillis()
+        )
+    }
+
     private fun requestPermission(context: Context): Boolean {
         if (Build.VERSION.SDK_INT < Build.VERSION_CODES.S) return true
         val intent = Intent(ACTION_REQUEST_SCHEDULE_EXACT_ALARM)

diff --git a/android/app/src/main/kotlin/com/presley/flexify/TimerService.kt b/android/app/src/main/kotlin/com/presley/flexify/TimerService.kt
@@ -101,14 +101,10 @@ class TimerService : Service() {
     }
 
     private fun sendTickBroadcast() {
-        sendBroadcast(
-            Intent(MainActivity.TICK_BROADCAST)
-                .putExtra("secondsLeft", timer.getRemainingSeconds())
-                .putExtra("secondsTotal", timer.getDurationSeconds())
-        )
+        sendBroadcast(Intent(MainActivity.TICK_BROADCAST))
     }
 
-    private fun onTimerExpired(intent: Intent?) {
+    private fun onTimerExpired() {
         Log.d("TimerService", "onTimerExpired duration=${timer.getDurationSeconds()}")
         timer.expire()
         vibrate()
@@ -169,7 +165,7 @@ class TimerService : Service() {
     }
 
     override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
-        if (intent != null && intent.action == TIMER_EXPIRED) onTimerExpired(intent)
+        if (intent != null && intent.action == TIMER_EXPIRED) onTimerExpired()
         else onTimerStart(intent);
         return START_STICKY
     }

diff --git a/lib/main.dart b/lib/main.dart
@@ -1,3 +1,4 @@
+import 'package:flexify/timer.dart';
 import 'package:flexify/database.dart';
 import 'package:flexify/graphs_page.dart';
 import 'package:flutter/material.dart';
@@ -11,17 +12,15 @@ late MethodChannel android;
 
 class AppState extends ChangeNotifier {
   String? selectedExercise;
-  int? secondsLeft;
-  int? secondsTotal;
+  Timer timer = Timer.emptyTimer();
 
   void selectExercise(String exercise) {
     selectedExercise = exercise;
     notifyListeners();
   }
 
-  void updateSeconds(int left, int total) {
-    secondsLeft = left;
-    secondsTotal = total;
+  void updateTimer(Timer newTimer) {
+    timer = newTimer;
     notifyListeners();
   }
 }
@@ -87,10 +86,16 @@ class _MyHomePageState extends State<MyHomePage>
   Widget build(BuildContext context) {
     android.setMethodCallHandler((call) async {
       if (call.method == 'tick') {
-        int left = call.arguments[0];
-        int total = call.arguments[1];
-        Provider.of<AppState>(context, listen: false)
-            .updateSeconds(left, total);
+        final newTimer = Timer(
+          Duration(milliseconds: call.arguments[0]),
+          Duration(milliseconds: call.arguments[1]),
+          DateTime.fromMillisecondsSinceEpoch(call.arguments[2], isUtc: true),
+        );
+
+        Provider.of<AppState>(
+          context,
+          listen: false,
+        ).updateTimer(newTimer);
       }
     });
 
@@ -100,13 +105,14 @@ class _MyHomePageState extends State<MyHomePage>
         builder: (BuildContext context) {
           return Scaffold(
             bottomSheet: Consumer<AppState>(builder: (context, value, child) {
-              final duration = value.secondsTotal ?? 0;
-              final elapsed = duration - (value.secondsLeft ?? 0);
+              final duration = value.timer.getDuration().inSeconds;
+              final elapsed = value.timer.getElapsed().inSeconds;
 
               return Visibility(
                 visible: duration > 0,
                 child: LinearProgressIndicator(
-                    value: duration == 0 ? 0 : elapsed / duration),
+                  value: duration == 0 ? 0 : elapsed / duration,
+                ),
               );
             }),
             body: SafeArea(

diff --git a/lib/start_plan_page.dart b/lib/start_plan_page.dart
@@ -50,7 +50,6 @@ class _StartPlanPageState extends State<StartPlanPage> {
     super.dispose();
   }
 
-
   void selectWeight() {
     weightController.selection = TextSelection(
       baseOffset: 0,
@@ -135,24 +134,19 @@ class _StartPlanPageState extends State<StartPlanPage> {
     final permission = await Permission.notification.request();
     if (!permission.isGranted) return;
     //                                           3s     3m30s
-    android.invokeMethod('timer', [210000, exercise]);
+    const duration = Duration(minutes: 3, seconds: 30);
+    android.invokeMethod('timer', [duration.inMilliseconds, exercise]);
 
     if (!mounted) return;
     final appState = Provider.of<AppState>(context, listen: false);
-    appState.updateSeconds(210000, 210000);
-  }
-
-  bool isTimerRunning(BuildContext context) {
-    final secondsLeft = context.watch<AppState>().secondsLeft;
-    if (secondsLeft == null) return false;
-    return secondsLeft > 0;
+    appState.updateTimer(appState.timer.increaseTimerDuration(duration));
   }
 
   @override
   Widget build(BuildContext context) {
     var title = widget.plan.days.replaceAll(",", ", ");
     title = title[0].toUpperCase() + title.substring(1).toLowerCase();
-    final timerRunning = isTimerRunning(context);
+    final timerRunning = context.watch<AppState>().timer.isRunning();
 
     return Scaffold(
       appBar: AppBar(
@@ -255,10 +249,15 @@ class _StartPlanPageState extends State<StartPlanPage> {
                 tooltip: "Add 1 min",
                 onPressed: () {
                   android.invokeMethod('add');
-                  final appState =
-                      Provider.of<AppState>(context, listen: false);
-                  appState.updateSeconds((appState.secondsLeft ?? 0) + 60,
-                      (appState.secondsTotal ?? 0) + 60);
+                  final appState = Provider.of<AppState>(
+                    context,
+                    listen: false,
+                  );
+                  appState.updateTimer(
+                    appState.timer.increaseTimerDuration(
+                      const Duration(minutes: 2),
+                    ),
+                  );
                 },
                 child: const Icon(Icons.add),
               ),

diff --git a/lib/timer.dart b/lib/timer.dart
@@ -0,0 +1,31 @@
+class Timer {
+  Timer(Duration totalTimerDuration, Duration elapsedTimerDuration,
+      DateTime timeStamp)
+      : _totalTimerDuration = totalTimerDuration,
+        _elapsedTimerDuration = elapsedTimerDuration,
+        _timeStamp = timeStamp;
+
+  static Timer emptyTimer() =>
+      Timer(Duration.zero, Duration.zero, DateTime.now());
+
+  Duration getElapsed() => _totalTimerDuration != Duration.zero
+      ? DateTime.now().difference(_timeStamp) + _elapsedTimerDuration
+      : Duration.zero;
+
+  Duration getDuration() => _totalTimerDuration;
+
+  bool isRunning() => (getDuration() - getElapsed()).inMilliseconds > 0;
+
+  Timer increaseTimerDuration(Duration increase) {
+    if (!isRunning()) return this;
+    return Timer(
+      _totalTimerDuration + increase,
+      _elapsedTimerDuration,
+      _timeStamp,
+    );
+  }
+
+  final Duration _totalTimerDuration;
+  final Duration _elapsedTimerDuration;
+  final DateTime _timeStamp;
+}
diff --git a/lib/timer_page.dart b/lib/timer_page.dart
@@ -21,8 +21,8 @@ class _TimerPageState extends State<TimerPage> {
   @override
   Widget build(BuildContext context) {
     final appState = context.watch<AppState>();
-    final duration = appState.secondsTotal ?? 0;
-    final elapsed = (duration) - (appState.secondsLeft ?? 0);
+    final duration = appState.timer.getDuration().inSeconds;
+    final elapsed = appState.timer.getElapsed().inSeconds;
 
     return Scaffold(
       appBar: AppBar(