今天在写一个音乐播放器，遇到一个问题就是在播放界面开始播放后，返回其他界面，就一直报setState() ...
When theTextFormFieldhasAutovalidateMode.always, the validation does happen immediately and the error message is displayed. Looking into the source code,Formruns the_validatefunction in the beginning of itsbuildmethod, before its_fieldshave registered. The_validatemethod goes over an empty Set of fi...
StatelessWidget 没有内部状态,Icon、 IconButton 和 Text 都是无状态 widget, 他们都是 StatelessWidget 的子类。 StatefulWidget 是动态的. 用户可以和其交互或者可以随时间改变 (也许是数据改变导致的UI更新)。Checkbox、 Radio、Slider, InkWell、Form、TextField 都是 StatefulWidget, 他们都是 StatefulWidget 的子类。
Without changing TextField values note That the first three TextFields are showing validation error, and Note that the last TextField is not showing the validation error. Expected results: We expect that all TextFormFields don't show validation error since the user did not change its content....
new TextField( controller: _phoneController, keyboardType: TextInputType.phone, decoration: new InputDecoration( helperText: 'Your unique ID.', hintText: 'Phone', errorText: _correctPhone ? null : 'phone length is 7 to 12 bits.',
the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ...
return TextFormField( decoration: InputDecoration( labelText: widget.label, hintText: widget.hintText, suffixIcon: widget.obscureText ? IconButton( onPressed: () { setState(() { _secureText = !_secureText; }); }, icon: Icon( _secureText ? Icons.visibility_off : Icons.visibility, ...
voidbeforeTextChanged(){int count=text.length-textSize;int end=selection.end;if(end<0){// 没有焦点的情况下直接返回,一般是event编辑的时候会出现textSize=text.length;return;}int start=end-count;if(isInsertSpan){spanList.forEach((element){if(element.start>start&&count!=0){element.setOffset(...
a message',border:OutlineInputBorder(borderRadius:BorderRadius.circular(20.0),),),),),SizedBox(width:8.0),IconButton(icon:Icon(Icons.send),onPressed:()=>_handleSubmitted(_textController.text),),],),),SizedBox(height:8.0),],),),);}Widget_buildMessage(Message message){finalisUserMessage=!me...
<activity>...<intent-filter><action android:name="android.intent.action.SEND"/><category android:name="android.intent.category.DEFAULT"/><data android:mimeType="text/*"/></intent-filter><intent-filter><action android:name="android.intent.action.SEND"/><category android:name="android.intent....