Flutter_输入框连接外部扫描设备 虚拟键盘弹起问题处理

child: KeyboardListener(
                      focusNode: _focusNode,
                      onKeyEvent: (KeyEvent event) {
                        if (event.runtimeType == KeyDownEvent) {
                          scanerIn += event.character.toString();
                          if (event.logicalKey.keyLabel == 'Enter') {
                            print("laststr:" + scanerIn);
                            scanerIn = '';
                          }
                        }
                      },
                      child: TextFormField(
                        controller: _controllerGoodsTitle,
                        showCursor: true,
                        readOnly: true,
                        maxLength: 50,
                        maxLines: 2, // 最大行数为5
                        cursorColor: Colors.pink,
                        onEditingComplete: () {},
                        decoration: const InputDecoration(
                          hintText: '请输入标题',
                          border: OutlineInputBorder(
                            borderSide: BorderSide(
                              style: BorderStyle.none,
                            ),
                          ),
                          focusedBorder: OutlineInputBorder(
                            borderSide: BorderSide(color: Colors.pink),
                            borderRadius:
                                BorderRadius.all(Radius.circular(16.0)),
                          ),
                          focusColor: Colors.pink,
                        ),
                      ),
                    ),