I'm VERY new to programming, and my teacher doesn't really teach. I've been trying to learn from her example code but I have no idea what I'm doing and I probably worded the question wrong because she never once explained what an argument/variable/object/anything is. Anyways, I'm attempting to make a program that allows me to add a restaurant with a name, phone number, and rating and then be able to update any section of that. E.g. Just the phone number. Here's the code I have:

public void update( View view)
{
    String u1 = updateold.getText().toString();
    String u2 = updatenewname.getText().toString();
    String u3 = updatenewphone.getText().toString();
    String u4 = updatenewrating.getText().toString();
    if(u1.isEmpty())
    {
        Message.message(getApplicationContext(),"Please enter the name of the restaurant you want to update!");
    }
    else {
        if (u2.isEmpty() & u3.isEmpty() & u4.isEmpty()) {
            Message.message(getApplicationContext(), "Please enter some information to be updated!");
        } else {
            int a = helper.updateName(u1, u2, u3, u4);
            if (a <= 0) {
                Message.message(getApplicationContext(), "Unsuccessful");
                updateold.setText("");
                updatenewname.setText("");
                updatenewphone.setText("");
                updatenewrating.setText("");
            } else {
                Message.message(getApplicationContext(), "Updated");
                updateold.setText("");
                updatenewname.setText("");
                updatenewname.setText("");
                updatenewphone.setText("");
                updatenewrating.setText("");
            }
        }

So that section right there is in my MainActivity.java, and it calls a.. Function? From a class to update it. That code is:

public int updateName(String oldName , String newName , String newPhone, String newRating)
{
    if(!newName.equals("")){
        SQLiteDatabase db = myhelper.getWritableDatabase();
        ContentValues contentValues = new ContentValues();
        contentValues.put(myDbHelper.NAME,newName);
        String[] whereArgs= {oldName};  //this is a string array object
        //String array stores and allows the program to look at each character individually
        //whereArgs = "JOE", then J is in index position 0, O is in index position 1, and E is in index position 2
        int count = db.update(myDbHelper.TABLE_NAME,contentValues, myDbHelper.NAME " = ?",whereArgs );
        return count;
    }
    if(!newPhone.equals("")) {
        SQLiteDatabase db = myhelper.getWritableDatabase();
        ContentValues contentValues = new ContentValues();
        contentValues.put(myDbHelper.PHONE_NUMBER, newPhone);
        String[] whereArgs = {oldName};  //this is a string array object
        //String array stores and allows the program to look at each character individually
        //whereArgs = "JOE", then J is in index position 0, O is in index position 1, and E is in index position 2
        int count = db.update(myDbHelper.TABLE_NAME, contentValues, myDbHelper.PHONE_NUMBER " = ?", whereArgs );
        return count;
    }
    if(!newRating.equals("")){
        //Message.message(myhelper.context, "Hit Non-Null Rating"); use this to test where the code is hitting
        SQLiteDatabase db = myhelper.getWritableDatabase();
        ContentValues contentValues = new ContentValues();
        contentValues.put(myDbHelper.RATING,newRating);
        String[] whereArgs= {oldName};  //this is a string array object
        //String array stores and allows the program to look at each character individually
        //whereArgs = "JOE", then J is in index position 0, O is in index position 1, and E is in index position 2
        int count = db.update(myDbHelper.TABLE_NAME,contentValues, myDbHelper.RATING " = ?",whereArgs );
        return count;
    }
    //should never hit the else if or the return after it, but I'm so confused I'm adding random code
    else if(newName.equals("") && newPhone.equals("") && newRating.equals("")){
        return 0;
    }
    return 0;
}

I can update the name of the restaurant, but when I try to change the phone number or rating it returns unsuccessful. I know it's hitting the block of code to update the phone/rating but then for some reason it's not updating it? I thought maybe the whereArgs was sending it to the wrong place, but if that were the case it would change the name of the restaurant to the new phone number/rating. I'm so confused. Please help and speak to me like I'm a toddler because at this point that's what I feel like.

I also realize that even if the code worked, it would only update one piece of the info at a time because of the returns inside each individual if statement, but one problem at a time.

CodePudding user response：

I noticed you had "where arguments" set incorrectly.

Try the code below.

public int updateName(String oldName , String newName , String newPhone, String newRating)
{
    if(newName.isNotEmpty()){
        SQLiteDatabase db = myhelper.getWritableDatabase();
        ContentValues contentValues = new ContentValues();
        contentValues.put(myDbHelper.NAME,newName);
        String[] whereArgs= {oldName};
        int count = db.update(myDbHelper.TABLE_NAME,contentValues, 
        myDbHelper.NAME   " = ?", whereArgs);
        return count;
    }
    if(newPhone.isNotEmpty()) {
        SQLiteDatabase db = myhelper.getWritableDatabase();
        ContentValues contentValues = new ContentValues();
        contentValues.put(myDbHelper.PHONE_NUMBER, newPhone);
        String[] whereArgs = {oldName};
        int count = db.update(myDbHelper.TABLE_NAME, contentValues,     
        myDbHelper.NAME   " = ?", whereArgs );
        return count;
    }
    if(newRating.isNotEmpty()){         
        SQLiteDatabase db = myhelper.getWritableDatabase();
        ContentValues contentValues = new ContentValues();
        contentValues.put(myDbHelper.RATING,newRating);
        String[] whereArgs= {oldName};         
        int count = db.update(myDbHelper.TABLE_NAME,contentValues,     
        myDbHelper.NAME   " = ?",whereArgs );
        return count;
    }
    if(newName.isEmpty() && newPhone.isEmpty() && newRating.isEmpty()){
        return 0;
    }
    return 0;
}