Question

我有这个问题：我写了一个应用程序，但SQLiteDatabase还没有工作。

我的数据库类代码：

package com.example.frauprinzssapp;

import android.content.ContentValues;
import android.content.Context;
import android.database.DatabaseErrorHandler;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;

public class database extends SQLiteOpenHelper{

public static final String DB_NAME = "users.db";
public static final String DB_TABLENAME = "users_table";
public static final String COL_1 = "id";
public static final String COL_2 = "name";
public static final String COl_3 = "class";
public static final String COL_4 = "right";

public database(Context context) {
    super(context, DB_NAME, null, 1);

}

@Override
public void onCreate(SQLiteDatabase db) {
    db.execSQL("create table "+DB_TABLENAME+"(id INTEGER PRIMARY KEY       AUTOINCREMENT, name TEXT, class TEXT, right INTEGER)");
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    db.execSQL("DROP TABLE IF EXIST "+DB_TABLENAME);
    onCreate(db);
}

public boolean insertdata(String name, String clas){
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues cv = new ContentValues();
    cv.put(COL_2, name);
    cv.put(COl_3, clas);
    cv.put(COL_4, 0);
    long result = db.insert(DB_TABLENAME, null, cv);
    if (result == -1){
        return false;
    }else{
        return true;
    }
}
}

主要代码是：

package com.example.frauprinzssapp;

import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

public class Main extends Activity {

List<String> addusers = new ArrayList<String>();
database myDb;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    myDb = new database(this);
}
//-----change view voids-----
public void main(View view){
    setContentView(R.layout.main);
}
public void adduser(View view){
    setContentView(R.layout.adduser);
}
public void removeuser(View view){
    setContentView(R.layout.removeuser);
}

//------actions------
public void add(){
    EditText name = (EditText) findViewById(R.id.aun);
    EditText clas = (EditText) findViewById(R.id.auc);
    if (name.toString() == null || clas.toString() == null){
        Toast.makeText(Main.this, "please fill in all textfields!",      Toast.LENGTH_LONG);
        return;
    }
try{
    myDb.insertdata(name.toString(), clas.toString());
    Toast.makeText(Main.this, "added user "+name.toString()+"!",   Toast.LENGTH_LONG);
}catch(Exception e){
    Toast.makeText(Main.this, "[ERROR] Could not create user maybe its   already created!", Toast.LENGTH_LONG);
}
}
public void remove(){

}
public void show(){

}
}

我用过

android:onClick="add"

使add（）void运行请现在它只是将随机内容放入sqlite pleaseeeee帮助

Answer 1

试试吧......

//------actions------
public void add(){
  EditText name = (EditText) findViewById(R.id.aun);
  EditText clas = (EditText) findViewById(R.id.auc);
  String name1 = name.getText().toString();
  String clas1 = clas.getText().toString();
  if (name1.equals("") || clas1.equals("")){
    Toast.makeText(Main.this, "please fill in all textfields!", Toast.LENGTH_LONG);
    return;
  }
  try{
    myDb.insertdata(name1, clas1);
    Toast.makeText(Main.this, "added user "+name1+"!", Toast.LENGTH_LONG);
  }catch(Exception e){
    Toast.makeText(Main.this, "[ERROR] Could not create user maybe its already created!", Toast.LENGTH_LONG);
  }
}

不幸的是，此应用已停止工作（SQLiteDatabase）

1 个答案: