在这个类中为你分配变量(使用这个类的好处是这个类在应用程序启动时启动,你可以在 app 的任何地方访问它)为:
MyApplication.class
import android.app.Application;
import android.support.v7.app.AppCompatActivity;
import com.google.android.gms.auth.api.Auth;
import com.google.android.gms.auth.api.signin.GoogleSignInOptions;
import com.google.android.gms.common.api.GoogleApiClient;
public class MyApplication extends Application {
private GoogleApiClient mGoogleApiClient;
private GoogleSignInOptions gso;
public AppCompatActivity activity;
public GoogleSignInOptions getGoogleSignInOptions(){
gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
.requestEmail()
.build();
return gso;
}
public GoogleApiClient getGoogleApiClient(AppCompatActivity activity, GoogleApiClient.OnConnectionFailedListener listener){
this.activity = activity;
mGoogleApiClient = new GoogleApiClient.Builder(this)
.enableAutoManage(this.activity, listener)
.addApi(Auth.GOOGLE_SIGN_IN_API, getGoogleSignInOptions())
.build();
return mGoogleApiClient;
}
}
在登录活动中
@Override
protected void onStart() {
mGoogleApiClient.connect();
super.onStart();
OptionalPendingResult<GoogleSignInResult> opr = Auth.GoogleSignInApi.silentSignIn(mGoogleApiClient);
if (opr.isDone()) {
Log.d("TAG", "Got cached sign-in");
GoogleSignInResult result = opr.get();
handleSignInResult(result);
} else {
opr.setResultCallback(new ResultCallback<GoogleSignInResult>() {
@Override
public void onResult(GoogleSignInResult googleSignInResult) {
//hideProgressDialog();
handleSignInResult(googleSignInResult);
}
});
}
}
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
gso = ((MyApplication) getApplication()).getGoogleSignInOptions();
mGoogleApiClient = ((MyApplication) getApplication()).getGoogleApiClient(LoginActivity.this, this);
}
@Override
protected void onStop() {
mGoogleApiClient.disconnect();
super.onStop();
}
在您要退出的第二个活动中
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
mGoogleApiClient = ((MyApplication) getApplication()).getGoogleApiClient(HomeActivity.this, this);
btnLogout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Auth.GoogleSignInApi.signOut(mGoogleApiClient).setResultCallback(
new ResultCallback<Status>() {
@Override
public void onResult(Status status) {
Intent i = new Intent(HomeActivity.this, LoginActivity.class);
startActivity(i);
finish();
}
});
}
});
}
在您的应用级 build.gradle 文件中,将 Google Play 服务声明为依赖项:
dependencies {
classpath 'com.android.tools.build:gradle:2.0.0'
classpath 'com.google.gms:google-services:1.5.0-beta2'
}
让 MyApplication 类扩展默认的 Application 类。另外,打开 Manifest 文件并在 application 元素中添加这行代码。
android:name=".MyApplication"