40 lines
960 B
Dart
40 lines
960 B
Dart
import 'package:flutter/material.dart';
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import 'package:flutter/scheduler.dart';
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class Fps extends StatefulWidget {
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const Fps({super.key});
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@override
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State<Fps> createState() => _FpsState();
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}
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class _FpsState extends State<Fps> {
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@override
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void initState() {
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SchedulerBinding.instance.addPersistentFrameCallback(_frame);
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super.initState();
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}
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int _lastFrameTime = 0;
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String _frameRate = "0 fps";
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void _frame(Duration elapsed) {
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int elapsedMicroseconds = elapsed.inMicroseconds;
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double elapsedSeconds = (elapsedMicroseconds - _lastFrameTime) * 1e-6;
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if (elapsedSeconds != 0) {
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_lastFrameTime = elapsedMicroseconds;
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setState(() {
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_frameRate = '${(1.0 / elapsedSeconds).toStringAsFixed(2)} fps';
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});
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}
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// redraw if mounted
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if (mounted) {
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SchedulerBinding.instance.scheduleFrame();
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}
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}
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@override
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Widget build(BuildContext context) {
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return Text(_frameRate);
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}
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}
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