I am programming an app that records phone calls and in this moment I am programming a menu and I want that when you click on an object in the menu you go to another activity; I tried to do this on both activities but when I click on a menu item the app crashes. Can you help me solve this crash? I leave you the code and the logcat of the crash
my code:
//menu
final Intent go = new Intent(this, records.class);
bottomNavigationView.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
switch (item.getItemId()) {
case R.id.action_start:
Toast.makeText(MainActivity.this, "Start", Toast.LENGTH_SHORT).show();
break;
case R.id.action_records:
Toast.makeText(MainActivity.this, "Records", Toast.LENGTH_SHORT).show();
startRec();
break;
}
return true;
}
private void startRec() {
startActivity(go);
}
});
//menu code end
crash logcat:
2021-01-12 16:30:09.637 5101-5101/com.example.ngoctri.introsliderexam E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.ngoctri.introsliderexam, PID: 5101
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.ngoctri.introsliderexam/com.conta.app.spyear.records}: java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.Window$Callback android.view.Window.getCallback()' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3365)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3601)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2066)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:223)
at android.app.ActivityThread.main(ActivityThread.java:7656)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.Window$Callback android.view.Window.getCallback()' on a null object reference
at android.support.v7.app.AppCompatDelegateImplBase.<init>(AppCompatDelegateImplBase.java:117)
at android.support.v7.app.AppCompatDelegateImplV9.<init>(AppCompatDelegateImplV9.java:149)
at android.support.v7.app.AppCompatDelegateImplV11.<init>(AppCompatDelegateImplV11.java:29)
at android.support.v7.app.AppCompatDelegateImplV14.<init>(AppCompatDelegateImplV14.java:54)
at android.support.v7.app.AppCompatDelegateImplV23.<init>(AppCompatDelegateImplV23.java:31)
at android.support.v7.app.AppCompatDelegateImplN.<init>(AppCompatDelegateImplN.java:31)
at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:198)
at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:183)
at android.support.v7.app.AppCompatActivity.getDelegate(AppCompatActivity.java:519)
at android.support.v7.app.AppCompatActivity.findViewById(AppCompatActivity.java:190)
at com.conta.app.spyear.records.<init>(records.java:13)
at java.lang.Class.newInstance(Native Method)
at android.app.AppComponentFactory.instantiateActivity(AppComponentFactory.java:95)
at android.app.Instrumentation.newActivity(Instrumentation.java:1253)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3353)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3601)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2066)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:223)
at android.app.ActivityThread.main(ActivityThread.java:7656)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)
at android.support.v7.app.AppCompatActivity.findViewById(AppCompatActivity.java:190)
at com.conta.app.spyear.records.<init>(records.java:13)
The problem is in your records activity on row 13. You're calling findViewById() too early at instance init time. Move the findViewById() to onCreate() or later, after setContentView().
Related
I couldn't find anything that was not initialized, and can't work my way up further. The same bit works for another piece of code that I've written, both are totally identical, and I can't figure out the problem. The complete error code is -
Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference.
The log file-
2021-07-30 21:29:33.613 17989-17989/com.elc.hostel E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.elc.hostel, PID: 17989
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.elc.hostel/com.elc.hostel.LoginActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3449)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3601)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2066)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:223)
at android.app.ActivityThread.main(ActivityThread.java:7656)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
at com.elc.hostel.LoginActivity.onCreate(LoginActivity.java:50)
at android.app.Activity.performCreate(Activity.java:8000)
at android.app.Activity.performCreate(Activity.java:7984)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1309)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3422)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3601)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2066)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:223)
at android.app.ActivityThread.main(ActivityThread.java:7656)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)
2021-07-30 21:29:35.004 17989-18005/com.elc.hostel W/System: A resource failed to call close.
The code-
public class LoginActivity extends AppCompatActivity {
EditText mEmail, mPassword;
Button mLogin;
ProgressBar mProgressBar;
FirebaseAuth fAuth;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
Objects.requireNonNull(getSupportActionBar()).hide();
mEmail = findViewById(R.id.LoginEmail);
mPassword = findViewById(R.id.LoginPassword);
mLogin = findViewById(R.id.LoginButton);
mProgressBar = findViewById(R.id.progressBarLog);
fAuth = FirebaseAuth.getInstance();
mLogin.setOnClickListener(new View.OnClickListener() {------------------Error
#Override
public void onClick(View v) {
String email = mEmail.getText().toString().trim();
String password = mPassword.getText().toString().trim();
if (TextUtils.isEmpty(email)){
mEmail.setError("Email is required");
return;
}
if (TextUtils.isEmpty(password)){
mPassword.setError("Password is required");
return;
}
if (password.length() < 6){
mPassword.setError("Password must be at least 6 characters");
return;
}
mProgressBar.setVisibility(View.VISIBLE);
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
at com.elc.hostel.LoginActivity.onCreate(LoginActivity.java:50)
Above stack indicates that mLogin is null.
Few cases in which findViewById() returns null are :
findViewById() is called before setContentView().
id passed in findViewById() is not present in layout set in setContentView().
In this case, setContentView() is not called.
Add setContentView() before accessing the views will solve the problem.
This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 2 years ago.
When the register button is clicked the app should load another activity however it just crashes. Tried looking here and here for help but I still couldn't fix it. I also tried removing 'implements View.OnClickListner' and using it how its shown in the examples and it didn't work. Also tried changing the xml file to a LinearLayout and that didn't work either. Thanks in advance!
public class LogInActivity extends AppCompatActivity implements View.OnClickListener {
//user input variables
EditText emailAddressInput;
EditText passwordInput;
Button logInButton;
Button registerButton;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//set the layout to activity_login.xml
setContentView(R.layout.activity_login);
//get user inputs and set to the variables
emailAddressInput = (EditText)findViewById(R.id.emailAddressInput);
passwordInput = (EditText)findViewById(R.id.passwordInput);
logInButton = (Button)findViewById(R.id.logInButton);
registerButton = (Button)findViewById(R.id.registerButton);
logInButton.setOnClickListener(this);
registerButton.setOnClickListener(this);
}
#Override
public void onClick(View view) {
Intent registerIntent = new Intent (LogInActivity.this,RegisterActivity.class);
switch (view.getId())
{
case R.id.logInButton:
break;
case R.id.registerButton:
startActivity(registerIntent);
break;
}
}
}
EDIT:
the logcat:
2020-04-04 16:02:10.759 12718-12718/com.example.blooddonorsystem E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.blooddonorsystem, PID: 12718
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.blooddonorsystem/com.example.blooddonorsystem.RegisterActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Spinner.setAdapter(android.widget.SpinnerAdapter)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3270)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3409)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Spinner.setAdapter(android.widget.SpinnerAdapter)' on a null object reference
at com.example.blooddonorsystem.RegisterActivity.onCreate(RegisterActivity.java:56)
at android.app.Activity.performCreate(Activity.java:7825)
at android.app.Activity.performCreate(Activity.java:7814)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1306)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3245)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3409)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
In your RegisterActivity, seems like the Spinner you are setting the adapter to is null. Make sure it has correct value, usually its an ArrayAdapter of String.
The error is not in LoginActivity but in RegisterActivity.There is a null pointer exception in RegisterActivity when you are setting adapter to a spinner.
intent = getIntent();
final String userid = intent.getStringExtra("userid");
I have Checked and verified that user id is coming but can not use in this child but before 2-3 days the same code working for me, from to now i have not changed anything
I have userid from Adapter position and i can use it in this activity and its working but in the given line of code error occur
reference = FirebaseDatabase.getInstance().getReference("Users").child(userid);
that can not pass java.lang.NullPointerException:
Can't pass null for argument 'pathString' in child()
Error is given as below:
2020-02-27 21:46:53.567 3248-3248/com.example.chat E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.chat, PID: 3248
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.chat/com.example.chat.MessageActivity}: java.lang.NullPointerException: Can't pass null for argument 'pathString' in child()
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2913)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
Caused by: java.lang.NullPointerException: Can't pass null for argument 'pathString' in child()
at com.google.firebase.database.DatabaseReference.child(com.google.firebase:firebase-database##19.2.0:96)
at com.example.chat.MessageActivity.onCreate(MessageActivity.java:175)
at android.app.Activity.performCreate(Activity.java:7136)
at android.app.Activity.performCreate(Activity.java:7127)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1271)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2893)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
Code part is given as below
fuser = FirebaseAuth.getInstance().getCurrentUser();
reference = FirebaseDatabase.getInstance().getReference("Users").child(userid);
reference.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
User user = dataSnapshot.getValue(User.class);
username.setText(user.getUsername());
Last_seen.setText(user.getStatus());
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 6 years ago.
When clicking a Button to switch from the main Activity to my "ColoursGame" Activity the app crashes.
I'm still a beginner so not an expert at debugging.
The main activity code
Button colorsGame = (Button) findViewById(R.id.colours);
colorsGame.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
startActivity(new Intent(MainActivity.this, ColoursGame.class));
}
});
Manifest new activity
<activity android:name=".ColoursGame"
android:label="ColourGame"
android:theme="#style/AppTheme.NoActionBar"></activity>
ColoursGame Activity OnCreate code
public class ColoursGame extends Activity {
int livesCount = 3;
String x;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_colours_game);
Button start = (Button) findViewById(R.id.startColors);
start.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
vSwitch.showNext();
x = String.valueOf(livesCount);
lives.setText(x);
text();
textColor();
backgroundColor();
start();
}
});
}
The Error
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.aynaar.numbersgameforkids, PID: 3278
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.aynaar.numbersgameforkids/com.aynaar.numbersgameforkids.ColoursGame}: java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.Window.findViewById(int)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2548)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6077)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.Window.findViewById(int)' on a null object reference
at android.app.Activity.findViewById(Activity.java:2323)
at com.aynaar.numbersgameforkids.ColoursGame.<init>(ColoursGame.java:42)
at java.lang.Class.newInstance(Native Method)
at android.app.Instrumentation.newActivity(Instrumentation.java:1078)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2538)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6077)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)
at com.aynaar.numbersgameforkids.ColoursGame.<init>(ColoursGame.java:42)
Don't call findViewById outside of onCreate, there's no Window to call findViewById at that point.
If you still get a NullPointer, then you must have #+id/startColors in activity_colours_game.xml
Answer explanation here
Button start = (Button) findViewById(R.id.startColors);
According to the error you are trying to reach a button that doesnt exist in your activity layout file (whatever it is). Check the id of your button and make sure it is placed on the layout page that related with your "ColoursGame" Activity.
I'm getting this error and I don't know why. This same code was working before; the problem started occuring after an update at some point.
Stack trace:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.domain.appname, PID: 17964
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.domain.appname/com.domain.appname.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.domain.appname.NavigationDrawerFragment.setUp(int, android.support.v4.widget.DrawerLayout)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2379)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2441)
at android.app.ActivityThread.access$800(ActivityThread.java:162)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1349)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5431)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:914)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:707)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.domain.appname.NavigationDrawerFragment.setUp(int, android.support.v4.widget.DrawerLayout)' on a null object reference
at com.domain.appname.MainActivity.onCreate(MainActivity.java:40)
at android.app.Activity.performCreate(Activity.java:6056)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2332)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2441)
at android.app.ActivityThread.access$800(ActivityThread.java:162)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1349)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5431)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:914)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:707)
Here's the offending code in MainActivity.java:
...
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (BuildConfig.DEBUG){ Log.d(TAG, "Created in debug mode"); }
NavigationDrawerFragment mNavigationDrawerFragment = (NavigationDrawerFragment)
getSupportFragmentManager().findFragmentById(R.id.navigation_drawer);
// Set up the drawer.
Log.d(TAG, "Setting up drawer");
mNavigationDrawerFragment.setUp( // Line 40
R.id.navigation_drawer,
(DrawerLayout) findViewById(R.id.drawer_layout)
);
...
I've found two questions that seem to have similar problems. (Here's the first and the second) The first doesn't seem relevant, and the second is unanswered.
I'm baffled. drawer_layout and navigation_drawer do not throw "symbol unresolved" errors. Like I said, this all used to work...
You are never calling Activity.setContentView(int). This is how it should be:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_containing_drawer);
// Rest.
}