I had built the app 3 days ago and the app was working fine. yesterday I updated the Kotlin plugin to 1.3.71-studio3.6-1 after that when I build my app and run it on my phone then after login, the main activity does not launch and the app stops working but I am getting a successful login in my Firebase. If I try to reopen the app, it does not open. all other activities are working fine but main_activity does not. the code of main activity was not modified
this is my manifest file
<application
android:allowBackup="false"
android:icon="@mipmap/g_c"
android:label="@string/app_name"
android:roundIcon="@mipmap/g_c_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".otp" />
<activity android:name=".Register" />
<activity android:name=".Login">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".MainActivity" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
</intent-filter>
</activity>
<meta-data
android:name="com.google.android.gms.ads.APPLICATION_ID"
android:value="xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" />
</application>
</manifest>
logcat error
03-30 01:40:05.051 6724-6724/com.trackerbin.guardchecker E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.trackerbin.guardchecker, PID: 6724
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.trackerbin.guardchecker/com.trackerbin.guardchecker.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.ads.AdView.loadAd(com.google.android.gms.ads.AdRequest)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3319)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3415)
at android.app.ActivityThread.access$1100(ActivityThread.java:229)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1821)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:7325)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.ads.AdView.loadAd(com.google.android.gms.ads.AdRequest)' on a null object reference
at com.trackerbin.guardchecker.MainActivity.onCreate(MainActivity.java:63)
at android.app.Activity.performCreate(Activity.java:6904)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1136)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3266)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3415)
at android.app.ActivityThread.access$1100(ActivityThread.java:229)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1821)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:7325)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)
MainActivity
public class MainActivity extends AppCompatActivity {
private Button mreport;
private Button mon;
private Button msignout;
private FirebaseAuth fAuth;
private Spinner mtower;
private ProgressBar mBar;
//AD
private AdView mAdView;
// Access a Cloud Firestore instance from your Activity
private final FirebaseFirestore db = FirebaseFirestore.getInstance();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mreport = findViewById(R.id.button);
mon = findViewById(R.id.onn);
fAuth = FirebaseAuth.getInstance();
mtower = findViewById(R.id.tower);
msignout = findViewById(R.id.signout);
mBar = findViewById(R.id.bar);
MobileAds.initialize(this, new OnInitializationCompleteListener() {
@Override
public void onInitializationComplete(InitializationStatus initializationStatus) {
}
});
mAdView = findViewById(R.id.adViewR);
AdRequest adRequest = new AdRequest.Builder().build();
mAdView.loadAd(adRequest);
if (fAuth.getCurrentUser() == null) {
startActivity(new Intent(getApplicationContext(), Login.class));
finish();
}
final String email = fAuth.getCurrentUser().getEmail();
final String phone = fAuth.getCurrentUser().getPhoneNumber();
mreport.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
mBar.setVisibility(View.VISIBLE);
String tower = mtower.getSelectedItem().toString();
String currentTime = new SimpleDateFormat("HH:mm:ss", Locale.getDefault()).format(new Date());
String currentDate = new SimpleDateFormat("dd-MM-yyyy", Locale.getDefault()).format(new Date());
Map<String, Object> values = new HashMap<>(); values.put(currentTime,email + phone);
db.collection("tower").document(tower)
.collection(currentDate).document("duty")
.collection("off").document(currentTime).set(values);
mBar.setVisibility(View.INVISIBLE);
Toast.makeText(MainActivity.this, "THANK YOU FOR REPORTING !", Toast.LENGTH_SHORT).show();
}
});
mon.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
mBar.setVisibility(View.VISIBLE);
String tower = mtower.getSelectedItem().toString();
String currentTime = new SimpleDateFormat("HH:mm:ss", Locale.getDefault()).format(new Date());
String currentDate = new SimpleDateFormat("dd-MM-yyyy", Locale.getDefault()).format(new Date());
Map<String, Object> values = new HashMap<>(); values.put(currentTime,email + phone);
db.collection("tower").document(tower)
.collection(currentDate).document("duty")
.collection("on").document(currentTime).set(values);
mBar.setVisibility(View.INVISIBLE);
Toast.makeText(MainActivity.this, "THANK YOU FOR REPORTING !", Toast.LENGTH_SHORT).show();
}
});
msignout.setOnClickListener
(
new View.OnClickListener()
{
@Override
public void onClick(View v) {
fAuth.signOut();
startActivity(new Intent(getApplicationContext(), Login.class));
finish();
}
}
);
}
@Override
public void onBackPressed() {
finishAffinity();
}
}