TextField(
    focusNode: _focusNode,
    controller: titleController,
    keyboardType: TextInputType.text,
    onChanged: (str) {
      context.read<Article>().title = str;
    },
    decoration: InputDecoration(
        hintText: '请输入查询关键字',
        contentPadding: const EdgeInsets.only(top: 0, bottom: 0),
        border: const OutlineInputBorder(
          borderSide: BorderSide(
            color: Colors.transparent,
          ),
        ),
        enabledBorder: const OutlineInputBorder(
          borderSide: BorderSide(
            color: Colors.transparent,
          ),
        ),
        disabledBorder: const OutlineInputBorder(
          borderSide: BorderSide(
            color: Colors.transparent,
          ),
        ),
        focusedBorder: const OutlineInputBorder(
          borderSide: BorderSide(
            color: Colors.transparent,
          ),
        ),
        suffixIcon: IconButton(
          padding: EdgeInsets.symmetric(horizontal: 0),
          icon: Icon(Icons.search),
          onPressed: () {
            _focusNode.unfocus();
          },
    )),
)