如何让Flutter中TextFormField的HintText垂直居中对齐？

提示文本偏上的核心原因是isDense: true会压缩输入框内部的上下内边距，再加上固定高度的SizedBox，导致文本无法自然垂直居中。以下两种方案可以解决这个问题：

方案一：调整contentPadding并保留isDense #

在InputDecoration中添加contentPadding，手动设置垂直方向的内边距，让提示文本对齐到中心：

SizedBox(
  height: 45,
  child: TextFormField(
    decoration: const InputDecoration(
      prefixIconConstraints: BoxConstraints(
        minWidth: 65,
      ),
      isDense: true,
      // 添加该行，调整垂直内边距适配容器高度
      contentPadding: EdgeInsets.symmetric(vertical: 12),
      prefixIcon: Icon(Icons.search, color: Color(0xFFD9D9D9), size: 30),
      hintText: "Ara...",
      hintStyle: TextStyle(color: Color.fromARGB(255, 184, 184, 184), fontSize: 19, fontFamily: "Inter Regular", fontWeight: FontWeight.bold),
      fillColor: Color.fromARGB(255, 64, 64, 73),
      filled: true,
      enabledBorder: OutlineInputBorder(
        borderRadius: BorderRadius.all(Radius.circular(15)),
        borderSide: BorderSide(color: Colors.transparent),
      ),
      focusedBorder: OutlineInputBorder(
        borderRadius: BorderRadius.all(Radius.circular(15)),
        borderSide: BorderSide(color: Colors.transparent),
      ),
    ),
    style: const TextStyle(fontFamily: "Inter Regular", fontSize: 19, color: Color.fromARGB(255, 167, 167, 167)),
  ),
),

方案二：移除isDense属性 #

isDense会强制缩小输入框内部间距，直接移除后，输入框会自动根据父容器高度调整文本垂直居中：

SizedBox(
  height: 45,
  child: TextFormField(
    decoration: const InputDecoration(
      prefixIconConstraints: BoxConstraints(
        minWidth: 65,
      ),
      // 移除isDense: true这一行
      prefixIcon: Icon(Icons.search, color: Color(0xFFD9D9D9), size: 30),
      hintText: "Ara...",
      hintStyle: TextStyle(color: Color.fromARGB(255, 184, 184, 184), fontSize: 19, fontFamily: "Inter Regular", fontWeight: FontWeight.bold),
      fillColor: Color.fromARGB(255, 64, 64, 73),
      filled: true,
      enabledBorder: OutlineInputBorder(
        borderRadius: BorderRadius.all(Radius.circular(15)),
        borderSide: BorderSide(color: Colors.transparent),
      ),
      focusedBorder: OutlineInputBorder(
        borderRadius: BorderRadius.all(Radius.circular(15)),
        borderSide: BorderSide(color: Colors.transparent),
      ),
    ),
    style: const TextStyle(fontFamily: "Inter Regular", fontSize: 19, color: Color.fromARGB(255, 167, 167, 167)),
  ),
),

两种方案都能解决问题，若需要更紧凑的布局优先选方案一，若希望输入框自动适配间距则选方案二。

内容的提问来源于stack exchange，提问作者Emir Bolat