android - 如何在输入值时动态更改文本字段的宽度

Question

我想在输入值时动态更改文本字段的宽度以适应所有输入文本。
这是我尝试过的。

var valueIncreaser = 30;
var textfieldSpanValue = 50.0;

Container(
  width: textfieldSpanValue,
  child: TextFormField(              
              onChanged: (text) {
                setState(() {
                  textfieldSpanValue = 20;
                  textfieldSpanValue = valueIncreaser + textfieldSpanValue * textfieldSpanValue;
                });
              },
              controller: myController,
              maxLength: 10,
              maxLengthEnforced: true,
              keyboardType: TextInputType.number,
              inputFormatters: <TextInputFormatter>[
                WhitelistingTextInputFormatter.digitsOnly
              ],
              ),
)

我想要看起来像这样的东西。

Answer 1

看起来您的代码中有一些简单的逻辑错误。您需要做的就是将宽度增量逻辑设置为:

textfieldSpanValue = valueIncreaser + textfieldSpanValue * text.length;

var valueIncreaser = 30;
var textfieldSpanValue = 50.0;

Container(
  width: textfieldSpanValue,
  child: TextFormField(              
              onChanged: (text) {
                setState(() {
                   textfieldSpanValue = 20;
                  textfieldSpanValue =
                      valueIncreaser + textfieldSpanValue * text.length;
                });
              },
              controller: myController,
              maxLength: 10,
              maxLengthEnforced: true,
              keyboardType: TextInputType.number,
              inputFormatters: <TextInputFormatter>[
                WhitelistingTextInputFormatter.digitsOnly
              ],
              ),
)