dart

问题 The Flutter docs show an example of rotating a "div" by 15 degrees, both for HTML/CSS and Flutter code: The Flutter code is: var container = new Container( // gray box child: new Center( child: new Transform( child: new Text( "Lorem ipsum", ), alignment: FractionalOffset.center, transform: new Matrix4.identity() ..rotateZ(15 * 3.1415927 / 180), ), ), ); And the relevant parts are new Transform and alignment: FractionalOffset.center and transform: new Matrix4.identity()..rotateZ(15 * 3.1415927

问题 I would like to make my Flutter app take up the entire screen in Android while still showing both the status bar and the navigation bar, with both of them transparent, to achieve the full screen look like in iOS. The status bar color can be easily changed, but right now I'm facing problems with getting the app to fill up the screen and making the navigation bar transparent at the same time. By default, the app is not drawn below the navigation bar at all (I've set the status bar color to be

问题 I would like to make my Flutter app take up the entire screen in Android while still showing both the status bar and the navigation bar, with both of them transparent, to achieve the full screen look like in iOS. The status bar color can be easily changed, but right now I'm facing problems with getting the app to fill up the screen and making the navigation bar transparent at the same time. By default, the app is not drawn below the navigation bar at all (I've set the status bar color to be

问题 I want to add a ripple on an item, it is working fine until I add a gradient on the item using BoxDecoration . Widget build(BuildContext context) { return Container( margin: EdgeInsets.symmetric(vertical: 8.0, horizontal: 16.0), child: Material( shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(4.0)), elevation: 6.0, shadowColor: Colors.grey[50], child: InkWell( onTap: () {}, child: Container( decoration: BoxDecoration( gradient: LinearGradient( begin: AlignmentDirectional

问题 I want to add a ripple on an item, it is working fine until I add a gradient on the item using BoxDecoration . Widget build(BuildContext context) { return Container( margin: EdgeInsets.symmetric(vertical: 8.0, horizontal: 16.0), child: Material( shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(4.0)), elevation: 6.0, shadowColor: Colors.grey[50], child: InkWell( onTap: () {}, child: Container( decoration: BoxDecoration( gradient: LinearGradient( begin: AlignmentDirectional

问题 Currently I have my password TextFormField like this: TextFormField( decoration: const InputDecoration( labelText: 'Password', icon: const Padding( padding: const EdgeInsets.only(top: 15.0), child: const Icon(Icons.lock), )), validator: (val) => val.length < 6 ? 'Password too short.' : null, onSaved: (val) => _password = val, obscureText: true, ); I want a button like interaction which will make password visible and invisible. Can I do it inside TextFormField ? Or I will have to make a Stack

问题 Currently I have my password TextFormField like this: TextFormField( decoration: const InputDecoration( labelText: 'Password', icon: const Padding( padding: const EdgeInsets.only(top: 15.0), child: const Icon(Icons.lock), )), validator: (val) => val.length < 6 ? 'Password too short.' : null, onSaved: (val) => _password = val, obscureText: true, ); I want a button like interaction which will make password visible and invisible. Can I do it inside TextFormField ? Or I will have to make a Stack

问题 Currently I have my password TextFormField like this: TextFormField( decoration: const InputDecoration( labelText: 'Password', icon: const Padding( padding: const EdgeInsets.only(top: 15.0), child: const Icon(Icons.lock), )), validator: (val) => val.length < 6 ? 'Password too short.' : null, onSaved: (val) => _password = val, obscureText: true, ); I want a button like interaction which will make password visible and invisible. Can I do it inside TextFormField ? Or I will have to make a Stack

问题 When I'm reading the source code I often see something like this (from TextField): /// {@macro flutter.widgets.editableText.keyboardType} final TextInputType keyboardType; What does the @macro mean? I found the answer so I'm posting it below as a self-answer Q&A. 回答1: A @macro is a way to insert some dartdoc documentation that has been written somewhere else. That way you don't have duplicate docs that you have to maintain. The string that follows @macro is the name of a template, which

问题 How can I use hashIt function in setter if editor gives this error The modifier async can not by applied to the body of a setter Future<String> hashIt(String password) async { return await PasswordHash.hashStorage(password); } set hashPass(String pass) async { // error here final hash = await hashIt(pass); _hash = hash; } compiller message: Error: Setters can't use 'async', 'async*', or 'sync*'. 回答1: The reason a setter cannot be async is that an async function returns a future, and a setter