完成空安全转换

lib/painter_system/anim/bezier3_player/bezier3_palyer.dart

@@ -83,8 +83,8 @@ class PaperPainter extends CustomPainter {
 
   final TouchInfo repaint;
 
-  PaperPainter({this.repaint}) : super(repaint: repaint);
-  List<Offset> pos;
+  PaperPainter({required this.repaint}) : super(repaint: repaint);
+  List<Offset> pos=[];
 
   @override
   void paint(Canvas canvas, Size size) {
@@ -118,7 +118,7 @@ class PaperPainter extends CustomPainter {
   }
 
   void _drawSelectPos(Canvas canvas,Size size) {
-    Offset selectPos = repaint.selectPoint;
+    Offset? selectPos = repaint.selectPoint;
     if (selectPos == null) return;
       selectPos = selectPos.translate(-size.width / 2, -size.height / 2);
     canvas.drawCircle(

lib/painter_system/anim/bezier3_player/touch_info.dart

@@ -13,7 +13,6 @@ class TouchInfo extends ChangeNotifier {
   List<Offset> get points => _points;
 
   set selectIndex(int value) {
-    assert(value != null);
     if (_selectIndex == value) return;
 
     _selectIndex = value;
@@ -36,6 +35,6 @@ class TouchInfo extends ChangeNotifier {
     notifyListeners();
   }
 
-  Offset get selectPoint =>
+  Offset? get selectPoint =>
       _selectIndex == -1 ? null : _points[_selectIndex];
 }

lib/painter_system/anim/circle_halo.dart

@@ -4,7 +4,7 @@ import 'dart:ui' as ui;
 import 'package:flutter/material.dart';
 
 class CircleHalo extends StatefulWidget {
-  const CircleHalo({Key key}) : super(key: key);
+  const CircleHalo({Key? key}) : super(key: key);
 
   @override
   _CircleHaloState createState() => _CircleHaloState();
@@ -12,7 +12,7 @@ class CircleHalo extends StatefulWidget {
 
 class _CircleHaloState extends State<CircleHalo>
     with SingleTickerProviderStateMixin {
-  AnimationController _ctrl;
+  late AnimationController _ctrl;
 
   @override
   void initState() {

lib/painter_system/anim/curve_shower/curve_anim_shower.dart

@@ -17,11 +17,11 @@ class _CurveAnimShowerState extends State<CurveAnimShower>
     with SingleTickerProviderStateMixin {
   PointData points = PointData();
 
-  AnimationController _ctrl;
+  late AnimationController _ctrl;
 
   final Duration animDuration = const Duration(milliseconds: 1000);
 
-  Animation<double> curveAnim;
+  late Animation<double> curveAnim;
 
   Map<String, Curve> maps = {
     'bounceOut': Curves.bounceOut,

lib/painter_system/anim/draw_path.dart

@@ -15,7 +15,7 @@ class DrawPath extends StatefulWidget {
 }
 
 class _DrawPathState extends State<DrawPath> with SingleTickerProviderStateMixin {
-  AnimationController _controller;
+ late AnimationController _controller;
 
   @override
   void initState() {
@@ -112,10 +112,10 @@ class PaperPainter extends CustomPainter {
 
     PathMetrics pms = path.computeMetrics();
     pms.forEach((pm) {
-      Tangent tangent = pm.getTangentForOffset(pm.length * repaint.value);
+      Tangent? tangent = pm.getTangentForOffset(pm.length * repaint.value);
       canvas.drawPath(pm.extractPath(0, pm.length * repaint.value), paint);
       canvas.drawCircle(
-          tangent.position, 5, Paint()..color = Colors.blue);
+          tangent?.position??Offset.zero, 5, Paint()..color = Colors.blue);
     });
   }
 

lib/painter_system/anim/spring_widget.dart

@@ -17,12 +17,12 @@ const double _kK = 3;
 class _SpringWidgetState extends State<SpringWidget> with SingleTickerProviderStateMixin {
   ValueNotifier<double> height = ValueNotifier(_kDefaultSpringHeight);
 
-  AnimationController _ctrl;
+ late AnimationController _ctrl;
 
   double s = 0;  // 移动距离
   double laseMoveLen = 0;
 
-  Animation<double> animation;
+  late Animation<double> animation;
 
   final Duration animDuration = const Duration(milliseconds: 500);
 
@@ -98,7 +98,7 @@ class SpringPainter extends CustomPainter {
   final int count;
   final ValueListenable<double> height;
 
-  SpringPainter({this.count = 20, this.height}):super(repaint: height);
+  SpringPainter({this.count = 20,required this.height}):super(repaint: height);
 
   Paint _paint = Paint()
     ..style = PaintingStyle.stroke