更新查询不适用于android中的sqlite

Question

final EditText eid=(EditText) findViewById(R.id.editText1); 

final EditText ename=(EditText)findViewById(R.id.editText2); 

final EditText epass=(EditText)findViewById(R.id.editText3); 

ContentValues values=new ContentValues(); 

values.put("studentid", eid.getText().toString()); 

values.put("studentname", ename.getText().toString()); 

values.put("password", epass.getText().toString()); 

if((db2.update("Studentprofile1",values,"studentid=" + eid.getText().toString(), null))!=-1) 
      { 
       Toast.makeText(editprofile.this, "Profile updated Successfully ", 2000).show(); 
       Intent inten=new Intent(getApplicationContext(),Elective1Activity.class); 
       startActivity(inten); 

      } 
      else 
      { 
       Toast.makeText(editprofile.this, "profile not updated", 2000).show(); 
      } 

错误：应用程序不幸停止。帮助我摆脱这个问题。

Answer 1

在这里，你可以找到所有的数据库相关的方法，如更新，搜索，计数，并添加：

package com.androidhive.androidsqlite; 

import java.util.ArrayList; 
import java.util.List; 

import android.content.ContentValues; 
import android.content.Context; 
import android.database.Cursor; 
import android.database.sqlite.SQLiteDatabase; 
import android.database.sqlite.SQLiteOpenHelper; 

public class DatabaseHandler extends SQLiteOpenHelper { 

    // All Static variables 
    // Database Version 
    private static final int DATABASE_VERSION = 1; 

    // Database Name 
    private static final String DATABASE_NAME = "contactsManager"; 

    // Contacts table name 
    private static final String TABLE_CONTACTS = "contacts"; 

    // Contacts Table Columns names 
    private static final String KEY_ID = "id"; 
    private static final String KEY_NAME = "name"; 
    private static final String KEY_PH_NO = "phone_number"; 

    public DatabaseHandler(Context context) { 
     super(context, DATABASE_NAME, null, DATABASE_VERSION); 
    } 

    // Creating Tables 
    @Override 
    public void onCreate(SQLiteDatabase db) { 
     String CREATE_CONTACTS_TABLE = "CREATE TABLE " + TABLE_CONTACTS + "(" 
       + KEY_ID + " INTEGER PRIMARY KEY," + KEY_NAME + " TEXT," 
       + KEY_PH_NO + " TEXT" + ")"; 
     db.execSQL(CREATE_CONTACTS_TABLE); 
    } 

    // Upgrading database 
    @Override 
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { 
     // Drop older table if existed 
     db.execSQL("DROP TABLE IF EXISTS " + TABLE_CONTACTS); 

     // Create tables again 
     onCreate(db); 
    } 

    /** 
    * All CRUD(Create, Read, Update, Delete) Operations 
    */ 

    // Adding new contact 
    void addContact(Contact contact) { 
     SQLiteDatabase db = this.getWritableDatabase(); 

     ContentValues values = new ContentValues(); 
     values.put(KEY_NAME, contact.getName()); // Contact Name 
     values.put(KEY_PH_NO, contact.getPhoneNumber()); // Contact Phone 

     // Inserting Row 
     db.insert(TABLE_CONTACTS, null, values); 
     db.close(); // Closing database connection 
    } 

    // Getting single contact 
    Contact getContact(int id) { 
     SQLiteDatabase db = this.getReadableDatabase(); 

     Cursor cursor = db.query(TABLE_CONTACTS, new String[] { KEY_ID, 
       KEY_NAME, KEY_PH_NO }, KEY_ID + "=?", 
       new String[] { String.valueOf(id) }, null, null, null, null); 
     if (cursor != null) 
      cursor.moveToFirst(); 

     Contact contact = new Contact(Integer.parseInt(cursor.getString(0)), 
       cursor.getString(1), cursor.getString(2)); 
     // return contact 
     return contact; 
    } 

    // Getting All Contacts 
    public List<Contact> getAllContacts() { 
     List<Contact> contactList = new ArrayList<Contact>(); 
     // Select All Query 
     String selectQuery = "SELECT * FROM " + TABLE_CONTACTS; 

     SQLiteDatabase db = this.getWritableDatabase(); 
     Cursor cursor = db.rawQuery(selectQuery, null); 

     // looping through all rows and adding to list 
     if (cursor.moveToFirst()) { 
      do { 
       Contact contact = new Contact(); 
       contact.setID(Integer.parseInt(cursor.getString(0))); 
       contact.setName(cursor.getString(1)); 
       contact.setPhoneNumber(cursor.getString(2)); 
       // Adding contact to list 
       contactList.add(contact); 
      } while (cursor.moveToNext()); 
     } 

     // return contact list 
     return contactList; 
    } 

    // Updating single contact 
    public int updateContact(Contact contact) { 
     SQLiteDatabase db = this.getWritableDatabase(); 

     ContentValues values = new ContentValues(); 
     values.put(KEY_NAME, contact.getName()); 
     values.put(KEY_PH_NO, contact.getPhoneNumber()); 

     // updating row 
     return db.update(TABLE_CONTACTS, values, KEY_ID + " = ?", 
       new String[] { String.valueOf(contact.getID()) }); 
    } 

    // Deleting single contact 
    public void deleteContact(Contact contact) { 
     SQLiteDatabase db = this.getWritableDatabase(); 
     db.delete(TABLE_CONTACTS, KEY_ID + " = ?", 
       new String[] { String.valueOf(contact.getID()) }); 
     db.close(); 
    } 


    // Getting contacts Count 
    public int getContactsCount() { 
     String countQuery = "SELECT * FROM " + TABLE_CONTACTS; 
     SQLiteDatabase db = this.getReadableDatabase(); 
     Cursor cursor = db.rawQuery(countQuery, null); 
     cursor.close(); 

     // return count 
     return cursor.getCount(); 
    } 

} 

Answer 2

制作方法在DB助手更新，然后从该类哪里我把这个方法传值。 。

和消防更新查询这样的..

public void updateTitle(long _Id, String FNAME,String LNAME, String DOB) 
{ 
    ContentValues args = new ContentValues(); 
     args.put(KEY_FNAMEID, FNAME); 
     args.put(KEY_LNAMEID, LNAME); 
     args.put(KEY_DOBID, DOB); 

    db.update(DATABASE_TABLE, args, KEY_STDID + "=" + _Id, null) > 0; 
} 

希望这可以帮助你..