如何在 cupertino switch flutter 中添加文本

我创建自定义窗口小部件，但其中没有立方体switch 动画.我希望这能满足你的需要

GestureDetector(
                                onTap: () {
                                  setState(() {
                                    val = !val;
                                  });
                                },
                                child: Container(
                                  width: size.width * 0.35,
                                  decoration: BoxDecoration(
                                      borderRadius: BorderRadius.circular(30),
                                      color: kSecondaryColor),
                                  child: Padding(
                                    padding: const EdgeInsets.all(8.0),
                                    child: Row(
                                      mainAxisAlignment:
                                          MainAxisAlignment.spaceBetween,
                                      children: [
                                        Container(
                                          width: 60,
                                          height: 30,
                                          decoration: BoxDecoration(
                                              borderRadius:
                                                  BorderRadius.circular(30),
                                              color: val
                                                  ? Colors.white
                                                  : kSecondaryColor),
                                          child: Center(
                                              child: Text(
                                            'BUY',
                                            style: TextStyle(
                                                fontWeight: FontWeight.bold,
                                                color: val
                                                    ? Colors.black
                                                    : Colors.white),
                                          )),
                                        ),
                                        Container(
                                          width: 60,
                                          height: 30,
                                          decoration: BoxDecoration(
                                              borderRadius:
                                                  BorderRadius.circular(30),
                                              color: val
                                                  ? kSecondaryColor
                                                  : Colors.white),
                                          child: Center(
                                              child: Text(
                                            'SELL',
                                            style: TextStyle(
                                                fontWeight: FontWeight.bold,
                                                color: val
                                                    ? Colors.white
                                                    : Colors.black),
                                          )),
                                        ),
                                      ],
                                    ),
                                  ),
                                ),
                              ),