How can the transfer of results be ensured upon the completion of another application or process?

In Android, to pass results from one application or process to another, the typical mechanisms are startActivityForResult (in older APIs) or ActivityResultLauncher (in newer ones), when dealing with interactions between activities.

If you need to get a result from another application, you can launch it via an Intent and wait for the result. When the called application finishes, the result is returned in the onActivityResult method.

Example with startActivityForResult:

Intent intent = new Intent(Intent.ACTION_PICK);
intent.setType("image/*");
startActivityForResult(intent, REQUEST_CODE);

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == REQUEST_CODE && resultCode == RESULT_OK) {
        Uri selectedImage = data.getData();
        // process the result
    }
}

For inter-process communication, you can use BroadcastReceiver with data passing via Intent, or ContentProvider, or Messenger/AIDL for more complex IPC.

If the context involves launching an external process (e.g., via Runtime.exec()), the result can be obtained by reading the process's output stream.