Question

我在Android中创建了一个应用程序，当您点击发送邮件按钮时，需要向保存在数据库中的所有联系人发送电子邮件，向每个联系人发送电子邮件，分别为

这个想法是在数据库中滑动每个用户的夫妻（电子邮件，得分）并将其传递给发送电子邮件的特定方法

我实施了send方法，以便接收电子邮件地址和相关分数我测试了发送电子邮件方法并正常工作，

唯一的问题是我无法定义适合的方式通过点击按钮传递所有电子邮件地址和每个用户的相关分数。

我的DatabaseHelper类如下：

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




public class DatabaseHelper extends SQLiteOpenHelper {

static final String dbName="demoDB";
static final String PlayerTable="Players";
static final String colID="PlayerID";
static final String colName="PlayerName";
static final String colEmail="Email";
static final String colScore="Score";
static final String colDept="Dept";

static final String deptTable="Dept";
static final String colDeptID="DeptID";
static final String colDeptName="DeptName";

static final String viewEmps="ViewEmps";


public DatabaseHelper(Context context) {
    super(context, dbName, null,33);

    // TODO Auto-generated constructor stub
}

@Override
public void onCreate(SQLiteDatabase db) {
    // TODO Auto-generated method stub

    db.execSQL("CREATE TABLE "+deptTable+" ("+colDeptID+ " INTEGER PRIMARY KEY , "+
            colDeptName+ " TEXT)");

    db.execSQL("CREATE TABLE "+PlayerTable+" ("+colID+" INTEGER PRIMARY KEY AUTOINCREMENT, "+
            colName+" TEXT, "+colEmail+" TEXT, "+colScore+" Integer, "+colDept+" INTEGER NOT NULL ,FOREIGN KEY ("+colDept+") REFERENCES "+deptTable+" ("+colDeptID+"));");


    db.execSQL("CREATE TRIGGER fk_empdept_deptid " +
            " BEFORE INSERT "+
            " ON "+PlayerTable+

            " FOR EACH ROW BEGIN"+
            " SELECT CASE WHEN ((SELECT "+colDeptID+" FROM "+deptTable+" WHERE "+colDeptID+"=new."+colDept+" ) IS NULL)"+
            " THEN RAISE (ABORT,'Foreign Key Violation') END;"+
            "  END;");

    db.execSQL("CREATE VIEW "+viewEmps+
            " AS SELECT "+PlayerTable+"."+colID+" AS _id,"+
            " "+PlayerTable+"."+colName+","+
            " "+PlayerTable+"."+colEmail+","+
            " "+PlayerTable+"."+colScore+","+
            " "+deptTable+"."+colDeptName+""+
            " FROM "+PlayerTable+" JOIN "+deptTable+
            " ON "+PlayerTable+"."+colDept+" ="+deptTable+"."+colDeptID
            );
    //Inserts pre-defined sections
    InsertDepts(db);

}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    // TODO Auto-generated method stub

    db.execSQL("DROP TABLE IF EXISTS "+PlayerTable);
    db.execSQL("DROP TABLE IF EXISTS "+deptTable);

    db.execSQL("DROP TRIGGER IF EXISTS dept_id_trigger");
    db.execSQL("DROP TRIGGER IF EXISTS dept_id_trigger22");
    db.execSQL("DROP TRIGGER IF EXISTS fk_empdept_deptid");
    db.execSQL("DROP VIEW IF EXISTS "+viewEmps);
    onCreate(db);
}

 void AddPlayer(Player emp)
{


     SQLiteDatabase db= this.getWritableDatabase();


    ContentValues cv=new ContentValues();

    cv.put(colName, emp.getName());
    cv.put(colName, emp.getEmail());
    cv.put(colScore, emp.getScore());
    cv.put(colDept, emp.getDept());
    //cv.put(colDept,2);

    db.insert(PlayerTable, colName, cv);
    db.close();


}

 int getPlayerCount()
 {
    SQLiteDatabase db=this.getWritableDatabase();
    Cursor cur= db.rawQuery("Select * from "+PlayerTable, null);
    int x= cur.getCount();
    cur.close();
    return x;
 }

 Cursor getAllPlayers()
 {
     SQLiteDatabase db=this.getWritableDatabase();



     //Cursor cur= db.rawQuery("Select "+colID+" as _id , "+colName+", "+colEmail+","+colScore+" from "+PlayerTable, new String [] {});
     Cursor cur= db.rawQuery("SELECT * FROM "+viewEmps,null);
     return cur;

 }

 Cursor getAllDepts()
 {
     SQLiteDatabase db=this.getReadableDatabase();
     Cursor cur=db.rawQuery("SELECT "+colDeptID+" as _id, "+colDeptName+" from "+deptTable,new String [] {});

     return cur;
 }

 void InsertDepts(SQLiteDatabase db)
 {
     ContentValues cv=new ContentValues();
        cv.put(colDeptID, 1);
        cv.put(colDeptName, "Sales");
        db.insert(deptTable, colDeptID, cv);
        cv.put(colDeptID, 2);
        cv.put(colDeptName, "IT");
        db.insert(deptTable, colDeptID, cv);
        cv.put(colDeptID, 3);
        cv.put(colDeptName, "HR");
        db.insert(deptTable, colDeptID, cv);
        db.insert(deptTable, colDeptID, cv);

 }

 public String GetDept(int ID)
 {
     SQLiteDatabase db=this.getReadableDatabase();

     String[] params=new String[]{String.valueOf(ID)};
     Cursor c=db.rawQuery("SELECT "+colDeptName+" FROM"+ deptTable+" WHERE "+colDeptID+"=?",params);
     c.moveToFirst();
     int index= c.getColumnIndex(colDeptName);
     return c.getString(index);
 }

 public Cursor getEmpByDept(String Dept)
 {
     SQLiteDatabase db=this.getReadableDatabase();
     String [] columns=new String[]{"_id",colName,colEmail,colScore,colDeptName};
     Cursor c=db.query(viewEmps, columns, colDeptName+"=?", new String[]{Dept}, null, null, null);
     return c;
 }

 public int GetDeptID(String Dept)
 {
     SQLiteDatabase db=this.getReadableDatabase();
     Cursor c=db.query(deptTable, new String[]{colDeptID+" as _id",colDeptName},colDeptName+"=?", new String[]{Dept}, null, null, null);
     //Cursor c=db.rawQuery("SELECT "+colDeptID+" as _id FROM "+deptTable+" WHERE "+colDeptName+"=?", new String []{Dept});
     c.moveToFirst();
     return c.getInt(c.getColumnIndex("_id"));

     }

 public int UpdateEmp(Player emp)
 {
     SQLiteDatabase db=this.getWritableDatabase();
     ContentValues cv=new ContentValues();
     cv.put(colName, emp.getName());
     cv.put(colScore, emp.getScore());
     cv.put(colDept, emp.getDept());
     return db.update(PlayerTable, cv, colID+"=?", new String []{String.valueOf(emp.getID())});

 }

 public void DeleteEmp(Player emp)
 {
     SQLiteDatabase db=this.getWritableDatabase();
     db.delete(PlayerTable,colID+"=?", new String [] {String.valueOf(emp.getID())});
     db.close();



 }

}

请帮帮我。

Answer 1

创建在dbHelper类中返回HashMap的getScores

public HashMap<String,String> getScores() {
HashMap<String,String> list = new HashMap<String,String>();
SQLiteDatabase db=this.getReadableDatabase();
Cursor cursor = db.rawQuery("Select email,sum(score) from players group by Email",null);
    if (cursor.moveToFirst()) {
        do {
            list.put(cursor.getString(0),cursor.getString(1));
        } while (cursor.moveToNext());
    }
    if (cursor != null && !cursor.isClosed()) {
        cursor.close();
    }
return list;}

使用此方法发送电子邮件假设

sendMail(String mailTo,String score);

HashMap<String,String> scores = dbHelper.getScores();
for(Map.Entry entry : scores.entrySet())
{
     sendMail(entry.getKey(),entry.getValue());
}

希望这有助于澄清它。

从SQLite DB电子邮件和用户分数中获取并分别将分数发送给每个用户

1 个答案: