I'm a newbie in programming, trying to implement a Google Signin in my test app. Folowing Google API documentation I've added all required dependencies at gradle files and registered my test app through OAuth... Further I wrote a code as described in example provided by Google, but my app crashes at the begining, before any user's action in Virtual device, and does not even set up via APK file at the real device....
What am i doing wrong?
Main (single) activity code:
package ru.podgorny.carcall;
import android.accounts.Account;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.TextView;
import com.google.android.gms.auth.api.signin.GoogleSignIn;
import com.google.android.gms.auth.api.signin.GoogleSignInAccount;
import com.google.android.gms.auth.api.signin.GoogleSignInClient;
import com.google.android.gms.auth.api.signin.GoogleSignInOptions;
import com.google.android.gms.common.SignInButton;
import com.google.android.gms.common.api.ApiException;
import com.google.android.gms.tasks.Task;
public class MainActivity extends AppCompatActivity {
SignInButton signInButton;
public static final int RC_SIGN_IN = 07;
public static final String TAG = "MainActivity";
TextView tw1;
TextView tw2;
GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
.requestEmail()
.requestProfile()
.build();
GoogleSignInClient mGSC = GoogleSignIn.getClient(this, gso);
@Override
protected void onCreate (Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
findViews();
}
private void findViews() {
signInButton = findViewById(R.id.idButtonGoogle);
tw1 = findViewById(R.id.textView1);
tw1 = findViewById(R.id.textView2);
}
public void onClick(View v) {
switch (v.getId()) {
case R.id.idButtonGoogle:
signIn();
break;
}
}
private void signIn() {
Intent signInIntent = mGSC.getSignInIntent();
startActivityForResult(signInIntent, RC_SIGN_IN);
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
// Result returned from launching the Intent from GoogleSignInClient.getSignInIntent(...);
if (requestCode == RC_SIGN_IN) {
// The Task returned from this call is always completed, no need to attach
// a listener.
Task<GoogleSignInAccount> task = GoogleSignIn.getSignedInAccountFromIntent(data);
handleSignInResult(task);
}
}
private void handleSignInResult(Task<GoogleSignInAccount> completedTask) {
try {
GoogleSignInAccount account = completedTask.getResult(ApiException.class);
updateUI(account);
} catch (ApiException e) {
Log.w(TAG, "signInResult:failed code=" + e.getStatusCode());
updateUI(null);
}
}
private void updateUI(GoogleSignInAccount account) {
tw1.setText("OK");
tw2.setText("Name: " + account.getGivenName() + ", Family name: " + account.getFamilyName() + ", Email: " + account.getEmail() + " image: " +
account.getPhotoUrl());
}
}
Activity.xml code:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="ru.podgorny.carcall.MainActivity"
>
<com.google.android.gms.common.SignInButton
android:id="@+id/idButtonGoogle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:foregroundGravity="top"
android:onClick="onClick"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:text="TextView"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="@+id/idButtonGoogle" />
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:text="TextView"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="@+id/textView1" />
</android.support.constraint.ConstraintLayout>
Manifest.xml by default:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="ru.podgorny.carcall">
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
Console logs :
03-23 08:35:32.774 5682-5682/? E/libprocessgroup: failed to make and chown /acct/uid_10060: Read-only file system
03-23 08:35:32.774 5682-5682/? W/Zygote: createProcessGroup failed, kernel missing CONFIG_CGROUP_CPUACCT?
03-23 08:35:32.775 5682-5682/? I/art: Not late-enabling -Xcheck:jni (already on)
03-23 08:35:33.180 5682-5682/ru.podgorny.carcall I/InstantRun: starting instant run server: is main process
03-23 08:35:33.746 5682-5682/ru.podgorny.carcall D/AndroidRuntime: Shutting down VM
03-23 08:35:33.753 5682-5682/ru.podgorny.carcall E/AndroidRuntime: FATAL EXCEPTION: main
Process: ru.podgorny.carcall, PID: 5682
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{ru.podgorny.carcall/ru.podgorny.carcall.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'android.os.Looper android.content.Context.getMainLooper()' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2236)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387)
at android.app.ActivityThread.access$800(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5254)
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:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.os.Looper android.content.Context.getMainLooper()' on a null object reference
at android.content.ContextWrapper.getMainLooper(ContextWrapper.java:101)
at com.google.android.gms.common.api.GoogleApi.<init>(Unknown Source)
at com.google.android.gms.auth.api.signin.GoogleSignInClient.<init>(Unknown Source)
at com.google.android.gms.auth.api.signin.GoogleSignIn.getClient(Unknown Source)
at ru.podgorny.carcall.MainActivity.<init>(MainActivity.java:35)
at java.lang.reflect.Constructor.newInstance(Native Method)
at java.lang.Class.newInstance(Class.java:1606)
at android.app.Instrumentation.newActivity(Instrumentation.java:1066)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2226)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387)
at android.app.ActivityThread.access$800(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5254)
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:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
03-23 08:35:33.827 5682-5695/ru.podgorny.carcall I/art: Background sticky concurrent mark sweep GC freed 2567(255KB) AllocSpace objects, 0(0B) LOS objects, 30% free, 773KB/1117KB, paused 18.376ms total 73.744ms
