同步适配器无法正常工作

Question

我是Android开发的新手。我想开发Android应用程序，它需要在线以及离线工作。如果它离线我将在本地sqLite Db中存储api调用方法名称类型和json字符串。一旦网络建立，我需要打电话给api。所以要实现这一点，我尝试使用同步适配器框架工作。但它没有正常工作。我在这里发布了我的代码。请帮助我。

我在下面提到了这些链接。

https://chariotsolutions.com/blog/post/android-data-sync/

http://www.zoftino.com/sync-data-between-device-and-server-in-android

http://www.oodlestechnologies.com/blogs/How-to-use-Sync-Adapter-In-Android

MainActivity

         public class MainActivity extends AppCompatActivity  {
    Button btnCreate, btnSignup;

    public String TAG = "MainActivity";
    public static final String AUTHORITY = Constants.AUTHORITY;
    public static final String ACCOUNT_TYPE = Constants.ACCOUNT_TYPE;
    public static final String ACCOUNT = Constants.ACCOUNT_NAME;
    public static final int SYNC_INTERVAL = 60;
    private Account mAccount;
    private ContentResolver mContentResolver;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        btnCreate = (Button) findViewById(R.id.btnAccount);
        btnSignup = (Button) findViewById(R.id.btnSignup);
try
{
        btnCreate.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                mAccount = CreateSyncAccount(getApplicationContext());
                mContentResolver = getContentResolver();
                ContentResolver.setIsSyncable(mAccount, AUTHORITY, 1);
                ContentResolver.setSyncAutomatically(mAccount, AUTHORITY, true);
                ContentResolver.addPeriodicSync(mAccount, AUTHORITY, Bundle.EMPTY, SYNC_INTERVAL);
                Log.i(TAG, "onClick:  AFter setSyncAutomatically" );
            }
        });
}catch (Exception ex)
{
    Log.i(TAG, "Error : " + ex.getMessage().toString());
}
    }

    private Account CreateSyncAccount(Context context) {

        Account newAccount = new Account(ACCOUNT, ACCOUNT_TYPE);
        AccountManager accountManager =
                (AccountManager) context.getSystemService(Context.ACCOUNT_SERVICE);
        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.GET_ACCOUNTS) != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.GET_ACCOUNTS}, 31);
        }
        Account accounts[] = accountManager.getAccountsByType(ACCOUNT_TYPE);
        if (accounts == null || accounts.length < 1) {
            if (accountManager.addAccountExplicitly(newAccount, null, null)) {
                return newAccount;
            } else {
                Log.i("sync activity", "error creating account");
            }
        } else {
            return accounts[0];
        }
        return null;
    }
}

清空Stub Authenticator和ContentProvider

身份验证服务

       public class AuthenticatorService extends Service {
        private static final String TAG = "AuthenticatorService";
        private static Authenticator sAccountAuthenticator = null;
        private Authenticator authenticator;
        @Override
        public void onCreate() {
            authenticator = new Authenticator(this);
        }
        @Nullable
        @Override
        public IBinder onBind(Intent intent) {

            return authenticator.getIBinder();
        }
    }

SyncService

    public class SyncService extends Service {
    private static SyncAdapter syncAdapter = null;
    private static final Object syncAdapterLock = new Object();
    public void onCreate() {
            synchronized (syncAdapterLock) {
                Log.i("Sync Started", "SyncService started");
                if (syncAdapter == null)
                    syncAdapter = new SyncAdapter(this, true);
                Log.i("Sync Stoped", "SyncService finished");
            }
    }
    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        return syncAdapter.getSyncAdapterBinder();
    }
}

同步适配器：

         public  class SyncAdapter extends AbstractThreadedSyncAdapter {
            private static final String TAG = SyncAdapter.class.getSimpleName();
            private ContentResolver contentResolver;
            public SyncAdapter(Context context, boolean autoInitialize) {
                super(context, autoInitialize);
            }

            public SyncAdapter(Context context, boolean autoInitialize, boolean allowParallelSyncs) {
                super(context, autoInitialize, allowParallelSyncs);
                this.contentResolver = context.getContentResolver();
                Log.i(TAG, "ReaderSyncAdapter created");
              //  manager = new ApolloBackendConfigurationManager(context);
            }

            @Override
            public void onPerformSync(Account account, Bundle extras, String authority, ContentProviderClient provider, SyncResult syncResult) {

                Log.i(TAG, "onPerformSync: Sync called" );
                Toast.makeText(getContext(), "Sync Called at " + Calendar.getInstance().getTime().toString(), Toast.LENGTH_SHORT).show();

            }
        }

清单

   <?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="arasan.com.syncadap">


    <uses-permission android:name="android.permission.READ_SYNC_STATS"/>
    <uses-permission android:name="android.permission.GET_ACCOUNTS" />
    <uses-permission android:name="android.permission.WRITE_SYNC_SETTINGS" />
    <uses-permission android:name="android.permission.READ_SYNC_SETTINGS" />
    <uses-permission android:name="android.permission.AUTHENTICATE_ACCOUNTS"  />
    <uses-permission android:name="android.permission.USE_CREDENTIALS"></uses-permission>

    <application
        android:allowBackup="false"
        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=".Activities.MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <provider
            android:name=".Provider.SyncContentProvider"
            android:authorities="@string/Authority"
            android:syncable="true"
            android:exported="false"
            android:label="SyncProvider" />

     <service android:name=".Services.AuthenticatorService">
         <intent-filter>
             <action android:name="android.accounts.AccountAuthenticator"/>
         </intent-filter>
             <meta-data
                 android:name="android.accounts.AccountAuthenticator"
                 android:resource="@xml/authenticator" />

     </service>

        <service
          android:name=".Services.SyncService"
            android:exported="true"
            android:process=":sync">
            <intent-filter>
                <action android:name="android.content.SyncAdapter"/>
            </intent-filter>
            <meta-data
                android:name="android.content.SyncAdapter"
                android:resource="@xml/syncadapter" />
        </service>

    </application>

</manifest>

身份验证器XML

<?xml version="1.0" encoding="utf-8"?>
<account-authenticator xmlns:android="http://schemas.android.com/apk/res/android"
    android:accountType="@string/AccountType"
    android:icon="@drawable/ic_launcher"
    android:smallIcon="@drawable/ic_launcher"
    android:label="@string/app_name"
    />

SyncAdapter XML

<?xml version="1.0" encoding="utf-8"?>
<sync-adapter xmlns:android="http://schemas.android.com/apk/res/android"
    android:contentAuthority="@string/Authority"
    android:accountType="@string/AccountType"
    android:userVisible="false"
    android:supportsUploading="false"
    android:allowParallelSyncs="false"
    android:isAlwaysSyncable="true">
</sync-adapter>