forms - 仅当聚焦于颤动时,如何在 TextFormField() 上显示计数器文本?
问题描述
我有TextFormField()
小部件,我想显示 CounterText 但仅在该字段集中时
还有一个侧面问题如何在焦点上更改字段背景颜色?
代码:-
TextFormField(
decoration: InputDecoration(
labelText: "Weight",
border: OutlineInputBorder(
borderSide: BorderSide(
color:Colors.grey[200],
width: 1,
style: BorderStyle.solid
),
gapPadding: 4.0
),
counterText:"Enter Your Weight",
),
),
解决方案
我认为最简单的方法是创建一个 Boolean 列表并在其上更新它们,以便您知道何时选择 TextForm 然后显示 counterText
Column(
children: <Widget>[
SizedBox(height: 50),
TextFormField(
onTap: () {
setState(() {
selected[0] = true;
selected[1] = false;
});
},
controller: textController,
decoration: InputDecoration(
labelText: "Weight",
border: OutlineInputBorder(
borderSide: BorderSide(
color: Colors.grey[200],
width: 1,
style: BorderStyle.solid),
gapPadding: 4.0),
counterText: selected[0] ? "Enter Your Weight" : ' ',
),
),
TextFormField(
onTap: () {
setState(() {
selected[0] = false;
selected[1] = true;
});
},
decoration: InputDecoration(
labelText: "Age",
border: OutlineInputBorder(
borderSide: BorderSide(
color: Colors.grey[200],
width: 1,
style: BorderStyle.solid),
gapPadding: 4.0),
counterText: selected[1] ? "Enter Your Age" : ' ',
),
)
],
)
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