Flutter 实现酷炫的3D效果示例代码
此文讲解3个酷炫的3D动画效果。
下面是要实现的效果:
Flutter 中3D效果是通过 Transform 组件实现的,没有变换效果的实现:
class TransformDemo extends StatelessWidget { @override Widget build(BuildContext context) { return Scaffold( appBar: AppBar( title: Text('3D 变换Demo'), ), body: Container( alignment: Alignment.center, color: Colors.white, child: Text('3D 变换Demo'), ), ); } }
通过 GestureDetector 组件添加滑动事件监听:
@override Widget build(BuildContext context) { return Scaffold( appBar: AppBar( title: Text('3D 变换Demo'), ), body: GestureDetector( onPanUpdate: (details) { print('$details'); }, child: Container( alignment: Alignment.center, color: Colors.white, child: Text('3D 变换Demo'), ), ), ); }
添加 Transform 对组件进入旋转:
@override Widget build(BuildContext context) { return Transform( transform: Matrix4.identity() ..setEntry(3, 2, 0.001) ..rotateX(pi/6) ..rotateY(pi/6), alignment: Alignment.center, child: Scaffold( appBar: AppBar( title: Text('3D 变换Demo'), ), body: GestureDetector( onPanUpdate: (details) { }, child: Container( alignment: Alignment.center, color: Colors.white, child: Text('3D 变换Demo'), ), ), )); }
将滑动的偏移和旋转进行关联:
class TransformDemo extends StatefulWidget { @override _TransformDemoState createState() => _TransformDemoState(); } class _TransformDemoState extends State<TransformDemo> { double _rotateX = .0; double _rotateY = .0; @override Widget build(BuildContext context) { return Transform( transform: Matrix4.identity() ..rotateX(_rotateX) ..rotateY(_rotateY), alignment: Alignment.center, child: Scaffold( appBar: AppBar( title: Text('3D 变换Demo'), ), body: GestureDetector( onPanUpdate: (details) { setState(() { _rotateX += details.delta.dy * .01; _rotateY += details.delta.dx * -.01; }); }, child: Container( alignment: Alignment.center, color: Colors.white, child: Text('3D 变换Demo'), ), ), )); } }
基本已经实现了3D效果,但效果比较生硬,尤其垂直方向旋转的时候远点和近点在屏幕上的宽度是一样,
添加近大远小的效果:
Transform( transform: Matrix4.identity() ..setEntry(3, 2, 0.001) ..rotateX(_rotateX) ..rotateY(_rotateY), ...
翻书效果
上面的效果类似于翻书的效果。
实现的原理:
将图片左右切割为两部分,两张图片共分割为4个新的组件,如下图,分别为1、2、3、4
代码实现:
_child1 = ClipRect( child: Align( alignment: Alignment.centerLeft, widthFactor: 0.5, child: child1, ), ); _child2 = ClipRect( child: Align( alignment: Alignment.centerRight, widthFactor: 0.5, child: child1, ), ); _child3 = ClipRect( child: Align( alignment: Alignment.centerLeft, widthFactor: 0.5, child: child2, ), ); _child4 = ClipRect( child: Align( alignment: Alignment.centerRight, widthFactor: 0.5, child: child2, ), );
将第一张图片放在第二种图片的上面,先旋转 组件2 从 0度到 90度,然后再旋转 组件3 从 -90度到0度,代码实现:
Row( mainAxisAlignment: MainAxisAlignment.center, children: <Widget>[ Stack( children: [ _child1, Transform( alignment: Alignment.centerRight, transform: Matrix4.identity() ..setEntry(3, 2, 0.001) ..rotateY(_animation1.value), child: _child3, ), ], ), Container( width: 3, color: Colors.white, ), Stack( children: [ _child4, Transform( alignment: Alignment.centerLeft, transform: Matrix4.identity() ..setEntry(3, 2, 0.001) ..rotateY(_animation.value), child: _child2, ) ], ) ], )
动画控制器设置:
@override void initState() { init(); _controller = AnimationController(vsync: this, duration: Duration(seconds: 5)) ..addListener(() { setState(() {}); }); _animation = Tween(begin: .0, end: pi / 2) .animate(CurvedAnimation(parent: _controller, curve: Interval(.0, .5))); _animation1 = Tween(begin: -pi / 2, end: 0.0).animate( CurvedAnimation(parent: _controller, curve: Interval(.5, 1.0))); _controller.forward(); super.initState(); }
其中 child1, child2为两种图片,代码如下:
_FlipUpDemoState( Container( width: 300, height: 400, child: Image.asset( 'assets/images/b.jpg', fit: BoxFit.cover, ), ), Container( width: 300, height: 400, child: Image.asset( 'assets/images/c.jpeg', fit: BoxFit.cover, ), ))
最后生成的效果就是开始的翻书效果。
上面是左右翻页效果,同理换成上下翻页效果:
@override Widget build(BuildContext context) { return Scaffold( appBar: AppBar(), body: Column( mainAxisAlignment: MainAxisAlignment.center, children: <Widget>[ Stack( children: [ _upperChild1, Transform( alignment: Alignment.bottomCenter, transform: Matrix4.identity() ..setEntry(3, 2, 0.003) ..rotateX(_animation1.value), child: _upperChild2, ), ], ), SizedBox( height: 2, ), Stack( children: [ _lowerChild2, Transform( alignment: Alignment.topCenter, transform: Matrix4.identity() ..setEntry(3, 2, 0.003) ..rotateX(_animation.value), child: _lowerChild1, ) ], ) ], ), ); }
到此这篇关于Flutter 实现酷炫的3D效果示例代码的文章就介绍到这了,更多相关Flutter 实现酷炫的3D效果内容请搜索我们以前的文章或继续浏览下面的相关文章希望大家以后多多支持我们!
赞 (0)