How to retrieve only the nodes from firebase database?-CodePudding

I have an app where users can create tasks for them to do throughout the day. Similar to a To-do list. I have a node in my firebase database called "Tasks" under this node is where all the tasks are added.

Here is a visual example:

I am of course able to add data to the firebase database. Here is the code for that:

taskTitle = titleTextField.text!
taskDescription = notesTextView.text

var tasks: [String: Any] = [:] // declaring empty dictionary

tasks["Description"] = taskDescription
tasks["Due Date"] = date_time

database.child("Tasks").child(taskTitle).setValue(tasks)

SO IF THE USER CREATES A NEW TASK, LET'S SAY THER CREATE "TASK 4", "TASK 5", "TASK 6" IT WILL LOOK LIKE THIS:

here is the jason data print:

    Tasks =     {
        "Task 1" =         {
            Description = Abcderf;
            "Due Date" = "Nov 17, 2021, 19:11";
        };
        "Task 2" =         {
            Description = Abcderf;
            "Due Date" = "Nov 17, 2021, 19:11";
        };
        "Task 3" =         {
            Description = Abcderf;
            "Due Date" = "Nov 17, 2021, 19:11";
        };
        "Task 4" =         {
            Description = Notes;
            "Due Date" = "";
        };
        "Task 5" =         {
            Description = Run;
            "Due Date" = "Nov 24, 2021, 12:11";
        };
        "Task 6" =         {
            Description = Run;
            "Due Date" = "Nov 24, 2021, 12:11";
        };
    };
}

Here is the code to print this snapshot:

var postRef: DatabaseReference? // declared outside of viewDidLoad()
var refHandle: DatabaseHandle? // declared outside of viewDidLoad()

//set the db ref
postRef = Database.database().reference()

//getting values from db
refHandle = postRef?.observe(DataEventType.value, with: { snapshot in
    self.listOftasks.append("")
})

I am just setting a breakpoint at self.listoftasks.append(""), and then in the console I am doing "po snapshot" which then prints the JSON object.

What do I need to do, to read only the name of the tasks?

CodePudding user response：

First up, if you only care about the tasks, you should load only the Tasks node instead of loading the entire database

tasksRef = Database.database().reference("Tasks")

Next up, you'll need to loop over the child nodes in your completion handler:

refHandle = tasksRef?.observe(DataEventType.value, with: { snapshot in
    for taskSnapshot in snapshot.children {
        print(taskSnapshot.key)
    }
})

For this, I recommend also checking out some of the previous questions on looping over child nodes in swift, such as:

Keep in mind: while the above only prints the keys of the tasks, it still retrieves the values of each node too. If you don't need the value in your code, consider keeping a separate node in your database with just the task names (and typically true values, since a path needs a value to exist) to reduce the bandwidth used.

Finally, having such sequential keys is a common anti-pattern in Firebase, so I recommend reading this classic post: Best Practices: Arrays in Firebase.