android - 从数据库中获取的 ListView 中的重复值

Question

我有一个来电历史应用程序。每次我调用它时，它都会获取号码并将其保存在数据库中，然后将其添加到列表中，列表又添加到 ListView 中。但我有一个问题，它从不检查旧值，并将重复的数字添加到数据库中，有什么办法可以避免这种情况吗？这是我的尝试。

public class Incoming_call_history extends Activity {

private ListView lv;
private ArrayAdapter<String> adapter;
private ArrayList<String>list;
DataSourceCall DS;
boolean duplicated=false;
String temp="";
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_incoming_call_history);
    DS= new DataSourceCall(this);
    DS.open();
    lv=(ListView)findViewById(R.id.callHistory);
    registerForContextMenu(lv);

    list=(ArrayList<String>) DS.getAllCalls();

    adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, list);
    lv.setAdapter(adapter);



    @SuppressWarnings("deprecation")
    Cursor mCursor = managedQuery(CallLog.Calls.CONTENT_URI, null, null,
            null, null);
    int number = mCursor.getColumnIndex(CallLog.Calls.NUMBER);
    int date = mCursor.getColumnIndex(CallLog.Calls.DATE);
    int duration = mCursor.getColumnIndex(CallLog.Calls.DURATION);
    int type = mCursor.getColumnIndex(CallLog.Calls.TYPE);


    while (mCursor.moveToNext()) {


        String num = mCursor.getString(number);
        String dur = mCursor.getString(duration);
        String datee = mCursor.getString(date);
        String calltype = mCursor.getString(type);
        Date d = new Date(Long.valueOf(datee));
        String callTypeStr = "";
        switch (Integer.parseInt(calltype)) {
        case CallLog.Calls.MISSED_TYPE:
            callTypeStr = "Missed";
            break;
        case CallLog.Calls.OUTGOING_TYPE:
            callTypeStr = "Outgoing";
            break;
        case CallLog.Calls.INCOMING_TYPE:
            callTypeStr = "Incoming";
            break;

        }

            boolean found = false;
        for (int ndx = 0; ndx < list.size(); ndx++)
        {
            if (num.equals(list.contains(num)))
                    {
                found = true;
                DS.deleteCall(num);
                adapter.notifyDataSetChanged();
                break;
                    }
        }
        if (!found)
        {
            DS.createCall(num);
            temp=num;
            Log.d("added succesfuly ", num);

        } 

        //  list.add("Phone number: "+num+"\n"+"Duration: " + dur+"\n"+"Type: " + callTypeStr+"\n"+"Call date: " + d+"\n");

    }
    mCursor.close();

    adapter.notifyDataSetChanged();


}}

Answer 1

如果不想在表中插入已经插入的手机号码，只需要检查手机号码是否已经插入

public int isUserAvailable(int number)
{
    int numberCount = 0;
    Cursor c = null;
    try
    {
        c = db.rawQuery("select p_number from user_table where p_number = ?", new String[] {String.valueOf(number)});

        if(c.getCount() != 0)
            numberCount = c.getCount();
    }
    catch(Exception e) {
        e.printStackTrace();
    } finally {
        if(c!=null) c.close();
    }
    return numberCount ;
}

如果不符合您的要求，请告诉我，我会尝试提供其他解决方案。