如何将索引从一个小部件传递到 flutter 中的另一个小部件

Question

Hi i have Pageview with weekIndex which show me the days of the week and I need to pass weekIndex to another widget this is my code for the Pageview:

Expanded(
                        child: PageView.builder(
                          controller: _pageController,
                          itemBuilder: (context, weekIndex) {
                            return Column(
                              children: [
                                Expanded(
                                  child: ListView.builder(
                                    scrollDirection: Axis.horizontal,
                                    itemCount: 7,
                                    itemBuilder:
                                        (BuildContext context, int index) {
                                      DateTime now = DateTime.now();
                                      int milliseconds = now
                                              .millisecondsSinceEpoch -
                                          (now.weekday - 1) *
                                              24 *
                                              60 *
                                              60 *
                                              1000 +
                                          weekIndex * 7 * 24 * 60 * 60 * 1000 +
                                          index * 24 * 60 * 60 * 1000;

and I need to pass weekIndex to this widget:

GridView.builder(
                          scrollDirection: Axis.vertical,
                          gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
                            crossAxisCount: 7,
                          ),
                          itemCount: 20,
                          itemBuilder:
                              (BuildContext context, int index) {
                            DateTime now = DateTime.now();
                            int milliseconds = now
                                .millisecondsSinceEpoch -
                                (now.weekday - 1) *
                                    24 *
                                    60 *
                                    60 *
                                    1000 +
                                weekIndex * 7 * 24 * 60 * 60 * 1000 +// here I need to pass the weekIndex
                                index * 24 * 60 * 60 * 1000;

                            DateTime dayDateTime =
                            DateTime.fromMillisecondsSinceEpoch(
                                milliseconds);
                            int monthIndex = dayDateTime.month - 1;

Answer 1

take another variable int temp = 0 inside the PageView.builder in the itemBuilder set temp = weekIndex , If you give the full code it would be better to say how to do it, if the GridView is inside the PageView then you can access weekIndex directly. If it is outside its outside then declaring another variable will do the trick.

Answer 2

you can use inherited widget to update variables without setState