我创建一个页面来按用户编辑数据。在此页面中有两张卡。在第一张卡中，我可以看到用户的图片;在第二张卡中，从手机中选择用户后可以看到用户的图片。或他们想要更新的图片。但是现在我的问题是，如果用户从手机中选择图像后出现第二张卡，该如何隐藏第一张卡。我知道可以通过使用Java中的Visibility来完成。是新的过滤器开发人员，我不知道该怎么做。我进行了很多搜索，但无法解决问题。
卡片1：
child: Card(
child: new Column(
children: <Widget>[
Image.network(image, width: 385,height: 300,
fit: BoxFit.cover,
),
OutlineButton(
onPressed: chooseImage,
child: Text('Choose Image'),
),
])
),
卡片2：
Card(
child: SizedBox(
width: 400.0,
height: 300.0,
child: new Padding(
padding:
const EdgeInsets.only(top: 2.0, bottom: 2.0),
child: Expanded(flex: 1,
child: showImage(),
)
),
),
),
整页：
class update_profilettt extends StatefulWidget {
var PostID;
update_profilettt({Key key, this.PostID}) : super(key: key);
@override
_update_profiletttState createState() => new _update_profiletttState(PostID);
}
class _update_profiletttState extends State<update_profilettt> {
MyPreferences _myPreferences = MyPreferences();
var PostID;
String uploadEndPoint;
_update_profiletttState(this. PostID);
Future<File> file;
String status = '';
String base64Image;
File tmpFile;
String errMessage = 'Error Uploading Image';
var data;
var _name = "";
// var _genderController = new TextEditingController();
var _nameController = new TextEditingController();
chooseImage() {
setState(() {
file = ImagePicker.pickImage(source: ImageSource.gallery);
});
setStatus('');
}
setStatus(String message) {
setState(() {
status = message;
});
}
startUpload() {
setStatus('Uploading Image...');
if (null == tmpFile) {
setStatus(errMessage);
return;
}
String NameImage =DateTime.now().millisecondsSinceEpoch.toString();
upload(NameImage);
}
upload(String NameImage) {
uploadEndPoint = 'http://xxxxxxx/up.php?id='+widget.PostID.toString();
print('yeyyyyddyy $uploadEndPoint');
http.post(uploadEndPoint, body: {
'id': widget.PostID.toString(),
}).then((result) {
setStatus(result.statusCode == 200 ? result.body : errMessage);
}).catchError((error) {
setStatus(error);
});
}
Widget showImage() {
return FutureBuilder<File>(
future: file,
builder: (BuildContext context, AsyncSnapshot<File> snapshot) {
if (snapshot.connectionState == ConnectionState.done &&
null != snapshot.data) {
tmpFile = snapshot.data;
base64Image = base64Encode(snapshot.data.readAsBytesSync());
return Flexible(
child: Card(
margin:EdgeInsets.all(10) ,
child: Image.file(
snapshot.data,
fit: BoxFit.cover,
),
),
);
} else if (null != snapshot.error) {
return const Text(
'Error Picking Image',
textAlign: TextAlign.center,
);
} else {
return const Text(
'',
textAlign: TextAlign.center,
);
}
},
);
}
Future<String> _ShowDialog(String msg) async {
return showDialog<String>(
context: context,
barrierDismissible: false, // user must tap button!
builder: (BuildContext context) {
return new AlertDialog(
title: new Text('Rewind and remember'),
content: new SingleChildScrollView(
child: new ListBody(
children: <Widget>[
new Text(msg),
],
),
),
actions: <Widget>[
new FlatButton(
child: new Text('Close'),
onPressed: () {
Navigator.of(context).pop();
},
),
],
);
},
);
}
void _editData() async {
// String NameImage =DateTime.now().millisecondsSinceEpoch.toString();
var url = 'http://xxxxxxxxxx/up.php?id='+widget.PostID.toString();
var response = await http.post(url, body: {
'id': widget.PostID.toString(),
// "id": _userController.text,
"name": _nameController.text,
"image": base64Image,
// "gender": _genderController.text,
});
if (response.statusCode == 200) {
_ShowDialog("Updated Successfully");
} else {
_ShowDialog("Updated Failer");
}
//onEditedAccount();
//print(_adresseController.text);
}
_fetchData() async {final url = "http://xxxxxxxx/nhy.php?id=${widget.PostID}";
final response = await http.get(url);
if (response.statusCode == 200) {
final map = json.decode(response.body);
final videosMap = map["result"];
setState(() {
this.data = videosMap;
_name = data[0]['name'];
image = data[0]['image'];
// _gender = data[0]['gender'];
print(data);
});
}
}
@override
void initState() {
super.initState();
_fetchData();
}
@override
Widget build(BuildContext context) {
_nameController= new TextEditingController(text: _name);
if(chooseImage !=null){
}
return new Scaffold(
appBar: AppBar(
title: Text("Edit Post"),
),
body: new Center(
child: data == null
? new CircularProgressIndicator()
: new ListView(
children: <Widget>[
new Padding(
padding: const EdgeInsets.fromLTRB(5, 10, 5, 5),
child: Column(
children: <Widget>[
new Padding(
padding:
const EdgeInsets.only(top: 10.0, bottom: 10.0),
child: Expanded(flex: 1,
child: Container(
child: Card(
child: new Column(
children: <Widget>[
Image.network(image, width: 385,height: 300,
fit: BoxFit.cover,
),
OutlineButton(
onPressed: chooseImage,
child: Text('Choose Image'),
),
])
),
),
),
),
Card(
child: SizedBox(
width: 400.0,
height: 300.0,
child: new Padding(
padding:
const EdgeInsets.only(top: 2.0, bottom: 2.0),
child: Expanded(flex: 1,
child: showImage(),
)
),
),
),
Card (
child: Column(
children: <Widget>[
SizedBox(
height: 10.0,
),
Container(
margin: EdgeInsets.all(4),
child: TextField(
maxLength: 10,
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'Name',
filled: true,
hintText: ''),
controller: _nameController,
),
),
SizedBox(
height: 5.0,
),
),
SizedBox(
height: 5.0,
),
),
),
),
),
SizedBox(
height: 5.0,
),
]
)
),
SizedBox(
width: double.infinity,
child: new FlatButton(
child: const Text('Update'),color: Colors.amber,
padding: EdgeInsets.fromLTRB(100, 18, 100, 18),
onPressed: () { _editData();
},
),
),
SizedBox(
height: 10.0,
),
],
),
)
],
),
));
}
}
答案 0 :(得分：0)
扑朔迷离中有一个 Visibility 小部件，您也可以用它包装卡
示例
bool visibilityController = true;
true为可见，false为不可见 因此，在选择卡时，请使用setstate进行切换。
setState(() {
});
Visibility(
visible: visibilityController,
child : //Your card
),
希望这就是您想要的。
为您的代码 您可以在showimage（）获取图像时执行此操作
Widget showImage() {
return FutureBuilder<File>(
future: file,
builder: (BuildContext context, AsyncSnapshot<File> snapshot) {
if (snapshot.connectionState == ConnectionState.done &&
null != snapshot.data) {
tmpFile = snapshot.data;
base64Image = base64Encode(snapshot.data.readAsBytesSync());
setState(() {
// added here
visibilityController = false;
});
return ........ your code