Disable some of the flutter checkboxes-CodePudding

I'm making a cinema app. I made the seat selection using checkbox. I would like to deactivate the checkbox of the reserved seat among 200 seats (column: 10 row: 20).

I know that if I input onChanged of the checkbox as null, it will be disabled. The problem is that I created 200 CheckBoxes in one CheckBox class. Is there a part to disable only a part of it?

Positioned(
            top: 45,
            left: 16,
            right: 16,
            child: GridView.count(
              shrinkWrap: true,
              crossAxisCount: 20,
              mainAxisSpacing: 2,
              crossAxisSpacing: 2,
              children: List.generate(200, (index) {
                int column = (index % 200).toInt();

                return Theme(
                  data: ThemeData(
                    primarySwatch: Colors.red,
                    unselectedWidgetColor: Colors.blueGrey,
                  ),
                  child: Checkbox(
                      checkColor: Colors.white,
                      value: widget.seat![widget.index!][column],
                      onChanged: (selected) {
                        setState(() {
                          // widget.selected[row][column] = selected!;
                          if (widget.seat![widget.index!][column] == false) {
                            widget.seat![widget.index!][column] = true;
                            seat_select  ;
                          } else if (widget.seat![widget.index!][column] == true) {
                            widget.seat![widget.index!][column] = false;
                            seat_select--;
                          }
                        });
                      }),
                );
              }),
            ),
          ),

CodePudding user response：

first, as you said, you need to put null if your seat is taken

              children: List.generate(200, (index) {
                // int column = (index % 200) // wont this always be 0?
                int column = index % 20;
                int row = index/20;

                return Theme(
                  child: Checkbox(
                      checkColor: Colors.white,
                      value: widget.seat![widget.index!][column],
                      onChanged: 
                        _isSeatTaken(row, column) ?
                           null
                           : (selected) {
                             // do something
                           },
                    ),
                  );
                },
              ),

and then, here you would put the logic for figuring out which seats are taken

bool _isSeatTaken(int row, int column) {
  return row == 10 && column == 20
}

CodePudding user response：

problem solving!!

Positioned(
            top: 45,
            left: 16,
            right: 16,
            child: GridView.count(
              shrinkWrap: true,
              crossAxisCount: 20,
              mainAxisSpacing: 2,
              crossAxisSpacing: 2,
              children: List.generate(200, (index) {
                int column = (index % 200).toInt();

                return Theme(
                  data: ThemeData(
                    primarySwatch: Colors.red,
                    unselectedWidgetColor: Colors.blueGrey,
                  ),
                  child: Checkbox(
                      checkColor: Colors.white,
                      value: widget.seat![widget.index!][column],
                      onChanged: _isSeatTaken(column)
                          ? null
                          : (selected) {
                              setState(() {
                                // widget.selected[row][column] = selected!;
                                if (widget.seat![widget.index!][column] ==
                                    false) {
                                  widget.seat![widget.index!][column] = true;
                                  seat_select  ;
                                } else if (widget.seat![widget.index!]
                                        [column] ==
                                    true) {
                                  widget.seat![widget.index!][column] = false;
                                  seat_select--;
                                }
                              });
                            }),
                );
              }),
            ),
          ),

bool _isSeatTaken(int column) {
    if (widget.seat![widget.index!][column] == true) {
      return true;
    }
    return false;
  }