我正在制作一个带有颤振的应用程序,我想要一个加载屏幕,同时从 Firestore 中获取数据我曾经在 android 中执行此操作 setvisibilty。似乎没有完全帮助
如果firebaseUser不是null,我想显示加载屏幕,这是我的initState方法
void initState() {
super.initState();
isRegistered();
}
@override
Widget build(BuildContext context) {
return Scaffold(
body: Container(
padding: EdgeInsets.all(32),
child: Form(
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text("Login"),
SizedBox(
height: 16,
),
Row(
mainAxisAlignment: MainAxisAlignment.spaceAround,
children: <Widget>[
Container(
width: 50,
child: TextFormField(
maxLength: 4,
keyboardType: TextInputType.number,
controller: countryCodeController,
decoration: InputDecoration(
hintText: '+251',
),
),
),
Container(
width: 200,
child: TextFormField(
maxLength: 9,
keyboardType: TextInputType.number,
controller: phonenumberController, …Run Code Online (Sandbox Code Playgroud) 我有这两个旋转物体,我希望.box它们像环和地球一样旋转.circle,但我似乎不知道该怎么做,我还想将图像分布在空间周围(如图像发布而不是字母它的图像.box)如果可能的话我真的很感激。
* {
margin: 0;
padding: 0;
box-sizing: border-box;
}
body {
display: flex;
justify-content: center;
align-items: center;
min-height: 100vh;
background-color: #000;
}
.circle {
transform-style: preserve-3d;
transform: perspective(1000px) rotateY(360deg) rotateX(15deg);
/* animation: animate 8s linear infinite; */
}
.circle span {
position: absolute;
top: 0;
left: 0;
background: #fff;
color: blueviolet;
font-size: 3em;
transform-origin: center;
transform-style: preserve-3d;
padding: 5px 11px;
border-top: 4px solid blueviolet;
border-bottom: 4px solid blueviolet;
transform: rotateY(calc(var(--i) * calc(360deg/30))) …Run Code Online (Sandbox Code Playgroud)