handle null object

app/src/main/java/com/example/yourcashiertest/activities/LoginActivity.java

@@ -58,23 +58,27 @@ public class LoginActivity extends AppCompatActivity {
         startActivity(new Intent(LoginActivity.this, RegisterActivity.class));
     }
     public void launchMain() {
-        viewModel.getListUser().observe(this, users -> {
-            for (int i = 0; i < users.size(); i++){
-                if (binding.etUsername.getText().toString().equals(users.get(i).getEmail())
-                        && binding.etPassword.getText().toString().equals(users.get(i).getPassword())){
-                    prefManager.setFirstLogin(false);
-                    binding.setLoading(false);
-                    startActivity(new Intent(LoginActivity.this, MainActivity.class).putExtra(DATA_LOGIN, users.get(i).getFullName()).addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK).addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP));
-                    finish();
-                    return;
-                }else if(!binding.etUsername.getText().toString().equals(users.get(i).getEmail())){
-                    binding.etUsername.setError("Email Not Found!");
-                }else if (!binding.etPassword.getText().toString().equals(users.get(i).getPassword())){
-                    binding.etPassword.setError("Password Wrong!");
+        try {
+            viewModel.getListUser().observe(this, users -> {
+                for (int i = 0; i < users.size(); i++) {
+                    if (binding.etUsername.getText().toString().equals(users.get(i).getEmail())
+                            && binding.etPassword.getText().toString().equals(users.get(i).getPassword())) {
+                        prefManager.setFirstLogin(false);
+                        binding.setLoading(false);
+                        startActivity(new Intent(LoginActivity.this, MainActivity.class).putExtra(DATA_LOGIN, users.get(i).getFullName()).addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK).addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP));
+                        finish();
+                        return;
+                    } else if (!binding.etUsername.getText().toString().equals(users.get(i).getEmail())) {
+                        binding.etUsername.setError("Email Not Found!");
+                    } else if (!binding.etPassword.getText().toString().equals(users.get(i).getPassword())) {
+                        binding.etPassword.setError("Password Wrong!");
+                    }
                 }
-            }
 
-        });
+            });
+        }catch (Exception e){
+            e.printStackTrace();
+        }
     }
     public void checkSession(){
         prefManager.setFirstLogin(false);