How to Display all associated subtask with specific taskId (Parent/Child relationship) --XAMARIN FORMS

Question

I am new to Xamarin Forms and I am trying to create a task app. In the app, there will be the task list page and when the user selects a task, it will bring to the task view page. In the task view page, it will display the task details and the subtasks. The issue is that I can't figure out how to display the associated subtasks for the specific task id.

I'm Trying to make a todo task app with subtasks.

My github repo for code:-- https://github.com/vishu2219/Todolist-new.git

Answer 1

Hello @v12doom ,

In the task view page, it will display the task details and the subtasks. The issue is that I can't figure out how to display the associated subtasks for the specific task id.

I check the source code your provided, there is a ListView to display the detailed task on Subtask page, an Entry and three buttons to add/delete/cancel task(There is also a ToolbarItem to add subtask). You want to select one item on MainPage, then display the task list (or click the ToolbarItem to add a task), then select a task to navigate to Subtask, right? If so, you can refer to the following code：

On Subtask Page:

async void OnItemAdded(object sender, EventArgs e)  
        {  
            var item = (task)BindingContext;  
            await Navigation.PushAsync(new subtaskadd()  
            {  
                BindingContext = new subtask()  
                {  
                    taskId = item.Id// ass a new subtask, pass the taskId   
                }  
            }) ;  
        }  
        async void OnClicklist(object sender, SelectedItemChangedEventArgs e)  
        {  
            if (e.SelectedItem != null)  
            {  
                await Navigation.PushAsync(new subtaskadd()  
                {  
                    BindingContext = e.SelectedItem as subtask  
                });  
            }  
        }  

On database.cs

 public async Task<int> SaveItemAsync2(subtask item)  
        {  
            List<subtask> items = await Database.Table<subtask>().Where(i => i.Id == item.Id).ToListAsync();// check if the subtask exists in the table  
            if (items.Count != 0)  
            {// if it is in the table, you can update  
                subtask st = items[0];  
                st.taskId = item.taskId;  
                st.sub = item.sub;  
                return await Database.UpdateAsync(st);  
            }  
            else  
            {  
                return await Database.InsertAsync(item);  
            }  
  
        }  

Best Regards,
Wenyan Zhang

---

If the answer is the right solution, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.