Create object from a class. Save the object. Call the object from a third class

Question

For this project, I'm using Android Studio. I've tried a bunch of things.

Goal: I would like to create an application which asks the user to input data. The data needs to be saved and later be called on another screen as a log history which the user can see.

What I've done: I have three classes: "InputScreen" "Logs" "LogHistoryScreen"

I've tried to create Logs object at InputScreen which works perfectly fine such as: Logs log1 = new Logs(); But I have no idea how to call the object log1 made in InputScreen from the LogHistoryScreen. Anyone who have any suggestions?

Thanks in advance.

Answer 1

Create a list of logs in InputScreen class:

List<Log> logs = new ArrayList();
logs.add(log1);
// same for next logs.

then create a method in InputScreen which will return the list of logs. Something like this:

public List<Log> getAllLogs() {
  return logs;
}

Call this method from LogHistoryScreen like:

InputScreen inputScreen = new InputScreen();
List<Log> logs = inputScreen.getAllLogs();

Answer 2

There are various options you could use here. I will mention a few here.

1) Passing through Intent.

Pass the Object as a parameter while you open the LogHistoryScreen from the InputScreen.

Please follow the below code to do so.

Intent intent = new Intent(this, LogHistoryScreen.class);
intent.putExtra("Key", yourObject);
startActivity(intent);

Receive the Object in the onCreate() of the LogHistoryScreen activity

Log log = (Log)getIntent().getSerializableExtra("Key");

The Log.class must implement Serializable.

public class Log implements Serializable
{
}

2) Store the Object in the Database and retrieve it from the other activity. This is particularly helpful if you need the data to persist across app sessions.

I think the first option will be more helpful for you.