Can you tell me about some 'builder' design patterns in Android?

The "Builder" pattern is used for creating complex objects step by step.

Examples of usage in Android:

1. AlertDialog.Builder: Creating dialogs with options to specify title, message, buttons, and other properties.

   new AlertDialog.Builder(context)
       .setTitle("Title")
       .setMessage("Message text")
       .setPositiveButton("OK", (dialog, which) -> {
           // Action upon OK click
       })
       .setNegativeButton("Cancel", null)
       .show();
   

2. NotificationCompat.Builder: Building notifications for the status bar.

   NotificationCompat.Builder builder = new NotificationCompat.Builder(context, CHANNEL_ID)
       .setSmallIcon(R.drawable.ic_notification)
       .setContentTitle("Notification title")
       .setContentText("Notification text")
       .setPriority(NotificationCompat.PRIORITY_DEFAULT);
   
   Notification notification = builder.build();
   // Sending notification via NotificationManager
   

3. Uri.Builder: Creating a URI with various parameters.

   Uri builtUri = new Uri.Builder()
       .scheme("http")
       .authority("www.example.com")
       .appendPath("path")
       .appendQueryParameter("param1", "value1")
       .build();
   

4. ViewModelProvider.Builder: (In Lifecycle Architecture Components) Building a factory for ViewModel.

   ViewModelProvider provider = new ViewModelProvider(activity, new ViewModelProvider.AndroidViewModelFactory(application));
   MyViewModel viewModel = provider.get(MyViewModel.class);
   

Main advantages of using the builder:

• Improves code readability when creating objects with many optional parameters.
• Avoids creating multiple constructors.
• Provides step-by-step object construction.
• The object is created only after calling the build() method.