Question

我正在写一个光标来从数据库中检索数据但是当控制到达光标时它会给出消息“Println需要消息”我很困惑任何人都可以在这方面帮助我。

代码：

import org.apache.commons.logging.Log;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.os.AsyncTask;
import android.widget.Toast;

public class TableA extends AsyncTask<String, Void, Void>{


    String Tablename = "Data";
    private String Column1 = "ID";
    private String Column2 = "FirstName";
    private String Column3 = "LastNAme";

    private String C1;
    private String C2;
    private String C3;

    Database rd;
    Cursor c;


    public final String r_Table = "CREATE TABLE " + Tablename + " (" + Column1+ " INTEGER PRIMARY KEY , " + Column2 + " TEXT, " + Column3 + " Text) ";



    public void setcolumn1(String ID1){
        C1=ID1;
        }
    public  int getcolumn1(){
        return Integer.parseInt(C1);
    }
    public void setcolumn2(String rname){
        C2=rname;
        }
    public String getcolumn2(){
        return C2;
    }
    public void setcolumn3(String Lname){
        C3=Lname;
        }
    public String getcolumn3(){
        return C3;
    }

    public ContentValues insertdata(){


        setcolumn1("1");
        setcolumn2("Ravi");
        setcolumn3("Kumar");

        ContentValues cv=new ContentValues();
        cv.put(Column1, Integer.valueOf(getcolumn1()));
        cv.put(Column2, getcolumn2());
        cv.put(Column3, getcolumn3());

        android.util.Log.i(Column1, String.valueOf(getcolumn1()));
        android.util.Log.i(Column2, getcolumn2());
        android.util.Log.i(Column3, getcolumn3());

            System.out.println(getcolumn1());
            System.out.println(getcolumn2());
            System.out.println(getcolumn3());



        return cv;          

    }
    @Override
    protected Void doInBackground(String... params) {




        c=rd.db.rawQuery("Select * from Data", null);
        if(c!=null){

            if(c.moveToFirst()){

                System.out.println("Column Count is: "+c.getColumnCount());
                System.out.println("Row Count is: "+c.getCount());
            }
            c.close();
        }
        return null;
    }

}

logcat的

05-01 15:57:57.247: W/ActivityThread(7163): Application com.example.Datamanager is waiting for the debugger on port 8100...
05-01 15:57:57.287: I/System.out(7163): Sending WAIT chunk
05-01 15:57:57.379: I/dalvikvm(7163): Debugger is active
05-01 15:57:57.537: I/System.out(7163): Debugger has connected
05-01 15:57:57.557: I/System.out(7163): waiting for debugger to settle...
05-01 15:57:57.759: I/System.out(7163): waiting for debugger to settle...
05-01 15:57:58.057: I/System.out(7163): waiting for debugger to settle...
05-01 15:57:58.259: I/System.out(7163): waiting for debugger to settle...
05-01 15:57:58.467: I/System.out(7163): waiting for debugger to settle...
05-01 15:57:58.677: I/System.out(7163): waiting for debugger to settle...
05-01 15:57:58.887: I/System.out(7163): waiting for debugger to settle...
05-01 15:57:59.087: I/System.out(7163): waiting for debugger to settle...
05-01 15:57:59.297: I/System.out(7163): waiting for debugger to settle...
05-01 15:57:59.509: I/System.out(7163): waiting for debugger to settle...
05-01 15:57:59.738: I/System.out(7163): waiting for debugger to settle...
05-01 15:57:59.937: I/System.out(7163): waiting for debugger to settle...
05-01 15:58:00.147: I/System.out(7163): waiting for debugger to settle...
05-01 15:58:00.347: I/System.out(7163): waiting for debugger to settle...
05-01 15:58:00.557: I/System.out(7163): waiting for debugger to settle...
05-01 15:58:00.757: I/System.out(7163): waiting for debugger to settle...
05-01 15:58:00.959: I/System.out(7163): waiting for debugger to settle...
05-01 15:58:01.169: I/System.out(7163): waiting for debugger to settle...
05-01 15:58:01.367: I/System.out(7163): waiting for debugger to settle...
05-01 15:58:01.568: I/System.out(7163): waiting for debugger to settle...
05-01 15:58:01.777: I/System.out(7163): debugger has settled (1489)
05-01 15:59:08.807: E/Datamanager(7163): println needs a message
05-01 15:59:11.368: I/Choreographer(7163): Skipped 93 frames!  The application may be doing too much work on its main thread.
05-01 15:59:11.748: D/gralloc_goldfish(7163): Emulator without GPU emulation detected.
05-01 15:59:12.846: I/Choreographer(7163): Skipped 100 frames!  The application may be doing too much work on its main thread.
05-01 15:59:21.756: D/dalvikvm(7163): Debugger has detached; object registry had 514 entries

任何人都可以指导我如何继续，因为消息不同，光标如何需要打印消息。

由于希瓦

Answer 1

问题是您从未将值设置为C1，C2和C3。

作为suggested in a different question，尝试这样做：

System.out.println("" + getcolumn1());

使用Cursor时出错

1 个答案: