活动 - 服务与领域不一致的数据

Question

我对存储在 Realm 数据库中的数据有疑问。如果我更改 MainActivity 上的值，当我尝试从 NotificationListenerService 读取它时，数​​据不正确。

这是我的模型：

public class Model extends RealmObject {

    String name;
    boolean checked;


    public Model() {}

    public Model(String name, boolean checked) {
        this.name = name;
        this.checked = checked;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public boolean isChecked() {
        return checked;
    }

    public void setChecked(boolean checked) {
        this.checked = checked;
    }

}

我从 Application 类填充数据库：

public class ExampleApplication extends Application{

    @Override
    public void onCreate() {
        super.onCreate();
        RealmConfiguration realmConfiguration = new RealmConfiguration.Builder(getApplicationContext()).deleteRealmIfMigrationNeeded().build();
        Realm.setDefaultConfiguration(realmConfiguration);
        Realm.getDefaultInstance().beginTransaction();
        Realm.getDefaultInstance().copyToRealm(new Model("Test1", true));
        Realm.getDefaultInstance().copyToRealm(new Model("Test2", true));
        Realm.getDefaultInstance().commitTransaction();
    }
}

我有一个活动：

• 设备设置中带有通知侦听器服务链接的按钮
• 显示模型状态的文本视图（选中或未选中）
• 用于更改模型检查值的按钮

这是代码：

public class MainActivity extends AppCompatActivity {

    Button btnEnableService;
    Button btnChangeValue;
    TextView tvStatus;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        btnEnableService = (Button) findViewById(R.id.btn_enable_service);
        btnChangeValue = (Button) findViewById(R.id.btn_change_value);
        tvStatus = (TextView) findViewById(R.id.tv_status);

        btnEnableService.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                try {
                    startActivity(new Intent(Settings.ACTION_NOTIFICATION_LISTENER_SETTINGS));
                }catch(ActivityNotFoundException anfe){
                    Toast.makeText(MainActivity.this, "Your device not supports Notification Listener Service", Toast.LENGTH_SHORT).show();
                }
            }
        });

        btnChangeValue.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                boolean status = Realm.getDefaultInstance().where(Model.class).equalTo("name", "Test1").findFirst().isChecked();
                Realm.getDefaultInstance().beginTransaction();
                Realm.getDefaultInstance().where(Model.class).equalTo("name", "Test1").findFirst().setChecked(!status);
                Realm.getDefaultInstance().commitTransaction();
                updateView();
            }
        });

    }

    @Override
    protected void onResume() {
        super.onResume();
        updateView();
    }

    private void updateView(){
        boolean status = Realm.getDefaultInstance().where(Model.class).equalTo("name", "Test1").findFirst().isChecked();
        tvStatus.setText("Status: " + status);
    }
}

当我单击 btnChangeValue 按钮时，我会更改 Realm 上的值，并且 textview 会使用新值进行更新。目前一切正常。

另一方面，我有一个服务来监听设备通知。很简单，只在LogCat上显示模型的状态值：

public class CustomNotificationListenerService extends NotificationListenerService{

    @Override
    public void onCreate() {
        super.onCreate();
    }

    @Override
    public void onNotificationPosted(StatusBarNotification sbn) {
        super.onNotificationPosted(sbn);
        boolean status = Realm.getDefaultInstance().where(Model.class).equalTo("name", "Test1").findFirst().isChecked();
        Log.i("XXX", "Status: " + status);
    }

    @Override
    public void onNotificationRemoved(StatusBarNotification sbn) {
        super.onNotificationRemoved(sbn);
    }
}

我的问题是模型的checked值不一致，我从MainActivity和NotificationListenerService得到不同的值。

我做错了什么？

提前致谢！

Answer 1

经过几个小时的测试，我解决了我的问题每次操作后关闭 Realm 实例。

所以，数据是一致的，我可以从 NotificationListenerService 和 MainActivity 查询。

示例应用程序

public class ExampleApplication extends Application{

    @Override
    public void onCreate() {
        super.onCreate();
        RealmConfiguration realmConfiguration = new RealmConfiguration.Builder(getApplicationContext()).deleteRealmIfMigrationNeeded().build();
        Realm.setDefaultConfiguration(realmConfiguration);
        Realm mRealm = Realm.getDefaultInstance();
        mRealm.beginTransaction();
        mRealm.copyToRealm(new Model("Test1", true));
        mRealm.copyToRealm(new Model("Test2", true));
        mRealm.commitTransaction();
        mRealm.close();
    }
}

MainActivity

...
@Override
protected void onCreate(Bundle savedInstanceState) {
    ...
    btnChangeValue.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Realm mRealm = Realm.getDefaultInstance();
            boolean status = mRealm.where(Model.class).equalTo("name", "Test1").findFirst().isChecked();
            mRealm.beginTransaction();
            mRealm.where(Model.class).equalTo("name", "Test1").findFirst().setChecked(!status);
            mRealm.commitTransaction();
            mRealm.close();
            updateView();
        }
    });
}
...

CustomNotificationListenerService

...
@Override
public void onNotificationPosted(StatusBarNotification sbn) {
    super.onNotificationPosted(sbn);
    Realm mRealm = Realm.getDefaultInstance();
    boolean status = mRealm.where(Model.class).equalTo("name", "Test1").findFirst().isChecked();
    mRealm.close();
    Log.i("XXX", "Status: " + status);
}
...

希望对你有帮助。