Question

在这里，我尝试按如下方式输入详细信息，然后需要检索它。

package com.example.orderform;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.DialogInterface.OnClickListener;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

public class NewActivity extends Activity{

  public void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_new);
  }
  public void onClick(View V) {
    Cursor c1=null;

    final SQLiteDatabase db;

    db=openOrCreateDatabase("Order", MODE_PRIVATE, null);

    db.execSQL("Create Table if not exists codeo(name Varchar,Address Varchar,code int(10),password int(10),phno int(10),email Varchar,ccode int(10));");

    final String name;
    final String Address;
    final String code;
    final String ccode;
    final String password;
    final String phno;
    final String email;
    final EditText n=(EditText) findViewById(R.id.editText1);
    final EditText c2=(EditText) findViewById(R.id.editText2);
    final EditText a=(EditText) findViewById(R.id.editText3);
    final EditText em=(EditText) findViewById(R.id.editText4);
    final EditText ph=(EditText) findViewById(R.id.editText5);
    final EditText cc=(EditText) findViewById(R.id.editText6);
    final EditText pass=(EditText) findViewById(R.id.editText7);

    name=n.getText().toString();
    code=c2.getText().toString();
    Address=a.getText().toString();
    phno=ph.getText().toString();
    email=em.getText().toString();
    ccode=cc.getText().toString();
    password=pass.getText().toString();
    if(name.equalsIgnoreCase("")||code.equalsIgnoreCase("")||ccode.equalsIgnoreCase("")||password.equalsIgnoreCase("")||Address.equalsIgnoreCase("")||phno.equalsIgnoreCase("")||email.equalsIgnoreCase(""))
    {
      Toast.makeText(getApplicationContext(), "No Field Can be Left Blank", Toast.LENGTH_LONG).show();
    }
    else
    {
      if(code.equals(ccode))
      {
        try
        {

          c1=db.rawQuery("Select * from codeo where code='"+code+"'", null);
          c1.moveToFirst();

          if(c1.getCount()<=0)
          {
            try
            {
              AlertDialog.Builder alrt=new AlertDialog.Builder(NewActivity.this);
              alrt.setTitle("CONFIRMATION");
              alrt.setCancelable(false);
              alrt.setMessage("Are You Sure that no more Changes on the above details");
              alrt.setPositiveButton("YES",new OnClickListener() {

                public void onClick(DialogInterface dialog, int which) {
                  // TODO Auto-generated method stub
                  try
              {
                db.execSQL("Insert into codeo values('"+name+"','"+code+"','"+ccode+"','"+Address+"','"+phno+"','"+email+"','"+password+"');");
                n.setText("");
                c2.setText("");
                pass.setText("");
                a.setText("");
                ph.setText("");
                em.setText("");
                cc.setText("");
                SharedPreferences sp= getSharedPreferences("My code",0);
                SharedPreferences.Editor e=sp.edit();
                e.putString("code1",code);
                /*e.putString("Address",Address);
                  e.putString("name",name);
                  e.putString("email", email);
                  e.putString("ccode",ccode);
                  e.putString("phno",phno);
                  e.putString("password",password);
                  e.putString("code",code);*/
                e.commit();
                Intent j=new Intent(getBaseContext(), New1Activity.class);
                startActivity(j);
              }
              catch(Exception e)
              {
                Toast.makeText(getApplicationContext(), "Exception", Toast.LENGTH_SHORT).show();
              }
                }
              });
              alrt.setNegativeButton("No", new DialogInterface.OnClickListener() {

                public void onClick(DialogInterface dialog, int which) {
                  // TODO Auto-generated method stub
                  dialog.cancel();
                }
              });
              AlertDialog al=   alrt.create();
              al.show();

            }
            catch(Exception er)
            {
              Toast.makeText(getApplicationContext(), "Exception in getcount", Toast.LENGTH_SHORT).show();
            }
          }
          else
          {
            Toast.makeText(getApplicationContext(), "Code taken", Toast.LENGTH_SHORT).show();
          }

        }
        catch(Exception er)
        {
          Toast.makeText(getApplicationContext(), "Exception in isfirst", Toast.LENGTH_SHORT).show();
        }
      }
      else
      {
        Toast.makeText(getApplicationContext(), "Code and Confirm Code doesn't Match", Toast.LENGTH_LONG).show();
        c2.setText("");
        cc.setText("");
      }
    }
  }
}

现在我正在尝试检索数据。但是我要求CursorIndexOutOfBoundsException索引0，大小为0.

package com.example.orderform;

import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;

public class New1Activity extends Activity {

  @Override
  public  void onCreate(Bundle savedInstanceState)
  {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_new1);


    String name,Address,code,phno,email,ccode,password;
    Cursor c;

    SQLiteDatabase db;

    SharedPreferences sp=getSharedPreferences("NewActivity", 0);

    name=sp.getString("name", "");   

    code=sp.getString("code", "");   

    Address=sp.getString("Address", "");



    phno=sp.getString("phno", "");

    email=sp.getString("email","");

    ccode=sp.getString("ccode", "");

    password=sp.getString("password", "");

    db=openOrCreateDatabase("Order", MODE_MULTI_PROCESS, null); 

    db.execSQL("Create Table if not exists codeo(name Varchar,Address Varchar,code 

      int(10),password int(10),phno int(10),email Varchar,ccode int(10));");

    c=db.rawQuery("Select * from codeo where code='"+code+"'", null); 

    c.moveToFirst();
    name=c.getString(c.getColumnIndex("name"));

    code=c.getString(c.getColumnIndex("code"));

    Address=c.getString(c.getColumnIndex("Address"));

    phno=c.getString(c.getColumnIndex("phno"));
    email=c.getString(c.getColumnIndex("email"));
    ccode=c.getString(c.getColumnIndex("ccode"));
    password=c.getString(c.getColumnIndex("password"));




    TextView n=(TextView) findViewById(R.id.textView6);

    n.setText(name);

    TextView c2=(TextView) findViewById(R.id.textView7);

    c2.setText(code);

    TextView a=(TextView) findViewById(R.id.textView8);

    a.setText(Address);

    TextView em=(TextView) findViewById(R.id.textView9);

    em.setText(email);

    TextView ph=(TextView) findViewById(R.id.textView10);

    ph.setText(phno);

    TextView cc=(TextView) findViewById(R.id.textView12);

    cc.setText(ccode);

    TextView pass=(TextView) findViewById(R.id.textView14);

    pass.setText(password);

  }
  public void onClick(View view)
  {
    startActivity(new Intent(this,CodeActivity.class));
  }


}

Answer 1

PROBLEM :- your cursor array do not contain any data in this case, in other words its `empty`

无法请求 index o如果size

cursor array is 0

好像你还记得

indexes start from zero in array..

所以实际上you request 0 index实际上是means you are requesting first element of the cursor array。

further means that cursor array contains at least one element位于index zero。

在这种情况下further derives that size of cursor array is not zero。

因此，当您请求if the size is 0然后should skip条件

的游标数组时，您需要添加一些条件

参考此图片

当您在此图片中request index 0时，will be 23。

但是if the size of the cursor array will be zero然后你cant request the 0 index ..

此处size of array is 6

而indexes of array are in the range of 0-5

Array indexing

错误：CursorIndexOutOfBoundsException请求索引0，大小为0

1 个答案: