I'm trying to make a to-do app. I create objects in card view, but when I press the delete icon on them when I first start the application, they do not delete the objects, they act as if I clicked the card and it gives this error. In the later ones, only the short text in red

Expanded(
          child: ListView.builder(
            itemCount: allTodo.length,
            itemBuilder: (context, index) {
              return Card(
                child: ListTile(
                  onTap: () {
                    setState(() {
                      _controllerTitle.text = allTodo[index].title;
                      clickedTodoID = allTodo[index].ID!;
                    });
                  },
                  title: Text(allTodo[index].title),
                  trailing: GestureDetector(
                    onTap: () {
                      _deleteTodo(allTodo[index].ID!, index);
                    },
                    child: Icon(Icons.delete),
                  ),
                ),
              );
            },
          ),
        ),

CodePudding user response：

Show me this function that you used.

_deleteTodo(allTodo[index].ID!, index);

CodePudding user response：

Most likely allTodo[index].ID is null here.

Try

onTap: () {
  if (allTodo[index].ID == null) {
    return;
  }
  setState(() {
    _controllerTitle.text = allTodo[index].title;
    clickedTodoID = allTodo[index].ID!;
  });
},

Use this snippet

return Card(
  child: ListTile(
    onTap: () {
      if (allTodo[index].ID == null) {
        print("id is null, cant perform add operation");
        return;
      }

      _controllerTitle.text = allTodo[index].title;
      clickedTodoID = allTodo[index].ID!;
      setState(() {});
    },
    title: Text(allTodo[index].title),
    trailing: GestureDetector(
      onTap: () {
        if (allTodo[index].ID != null) {
          _deleteTodo(allTodo[index].ID!, index);
          setState(() {});
        } else {
          print("id is null, cant perform Delete operation");
        }
      },
      child: Icon(Icons.delete),
    ),
  ),
);