Question

我实现了一个ContentObserver，它工作正常。但现在，每当ContentObserver通知CallLog.Calls内容提供程序中的某些更改时，它都会运行onChange（）方法而不会停止。

我希望我的观察者对内容提供商中已更改的每个项目运行一次。因此，如果已将5个新项添加到CallLog.Calls内容提供程序，则必须通知观察者5次，并且对于每个通知观察者，必须发生对onChange（）方法的新调用。

这是我的代码。

public class RatedCalls extends ListActivity {

private static final String LOG_TAG = "RATEDCALLSOBSERVER";
private Handler handler = new Handler();
private RatedCallsContentObserver callsObserver = null;
private SQLiteDatabase db;
private Cursor cursor;
StringBuilder sb = new StringBuilder();
OpenHelper openHelper = new OpenHelper(RatedCalls.this);

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    this.getApplicationContext()
            .getContentResolver()
            .registerContentObserver(
                    android.provider.CallLog.Calls.CONTENT_URI, true,
                    new RatedCallsContentObserver(handler));
    Log.d("FILLLIST", "calling from onCreate()");
}

class RatedCallsContentObserver extends ContentObserver {
    public RatedCallsContentObserver(Handler h) {
        super(h);
    }

    @Override
    public boolean deliverSelfNotifications() {
        return true;
    }

    @Override
    public void onChange(boolean selfChange) {
        Log.d(LOG_TAG, "RatedCallsContentObserver.onChange( " + selfChange
                + ")");
        super.onChange(selfChange);
        fillList();
    }
}

private void fillList() {

    cursor = getContentResolver().query(
            android.provider.CallLog.Calls.CONTENT_URI, null, null, null,
            android.provider.CallLog.Calls.DATE + " DESC ");
    Log.d("FILLLIST", "Calling from filllist");

    db = openHelper.getWritableDatabase();

    startManagingCursor(cursor);
    int numberColumnId = cursor
            .getColumnIndex(android.provider.CallLog.Calls.NUMBER);
    int durationId = cursor
            .getColumnIndex(android.provider.CallLog.Calls.DURATION);
    int contactNameId = cursor
            .getColumnIndex(android.provider.CallLog.Calls.CACHED_NAME);
    int dateId = cursor.getColumnIndex(android.provider.CallLog.Calls.DATE);
    int numTypeId = cursor
            .getColumnIndex(android.provider.CallLog.Calls.CACHED_NUMBER_TYPE);

    Date dt = new Date();
    int hours = dt.getHours();
    int minutes = dt.getMinutes();
    int seconds = dt.getSeconds();
    String currTime = hours + ":" + minutes + ":" + seconds;

    ArrayList<String> callList = new ArrayList<String>();
    cursor.moveToFirst();

    String contactNumber = cursor.getString(numberColumnId);
    String contactName = cursor.getString(contactNameId);
    String duration = cursor.getString(durationId);
    String callDate = DateFormat.getDateInstance().format(dateId);
    String numType = cursor.getString(numTypeId);

    ContentValues values = new ContentValues();

    values.put("contact_id", 1);
    values.put("contact_name", contactName);
    values.put("number_type", numType);
    values.put("contact_number", contactNumber);
    values.put("duration", duration);
    values.put("date", callDate);
    values.put("current_time", currTime);
    values.put("cont", 1);
    getBaseContext().getContentResolver().notifyChange(
            android.provider.CallLog.Calls.CONTENT_URI,
            new RatedCallsContentObserver(handler));
    db.insert(CallDataHelper.TABLE_NAME, null, values);
    Toast.makeText(getBaseContext(), "Inserted!", Toast.LENGTH_LONG);
    callList.add("Contact Number: " + contactNumber + "\nContact Name: "
            + contactName + "\nDuration: " + duration + "\nDate: "
            + callDate);

    setListAdapter(new ArrayAdapter<String>(this, R.layout.listitem,
            callList));
    ListView lv = getListView();
    lv.setTextFilterEnabled(true);

    lv.setOnItemClickListener(new android.widget.AdapterView.OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                int position, long id) {

            Toast.makeText(getApplicationContext(),
                    ((TextView) view).getText(), Toast.LENGTH_SHORT).show();

        }
    });
}   
}

Answer 1

您更改了fillList()内的数据库内容，因此会一次又一次地调用RatedCallsContentObserver.onChange() ...

Answer 2

在此查询中包含日期检查.android.provider.CallLog.Calls.DATE＆gt;最后日期

cursor = getContentResolver().query(
        android.provider.CallLog.Calls.CONTENT_URI, null, null, null,
        android.provider.CallLog.Calls.DATE + " DESC ");

希望这会对你有所帮助

Android ContentObserver从未停止过

2 个答案: