Question

I am trying to get the primary key “_id” from the selected group using code

groupPositionID is a global variable initialized like this
and IngredientListGroup_cursor is a group cursor which fetches the group data for expanable list view.

String groupPositionID=null;
Cursor IngredientListGroup_cursor;

in the oncreate code:

public void onCreate(Bundle savedInstanceState) {
IngredientListGroup_cursor=helper.GetIngredientsList();
}

ExpandableIngredietnsList.setOnGroupClickListener(new OnGroupClickListener(){

                @Override
                public boolean onGroupClick(
                        ExpandableListView paramExpandableListView,
                        View paramView, int paramInt, long paramLong) {
                    // TODO Auto-generated method stub

                    groupPositionID=IngredientListGroup_cursor.getString(0);

                    Toast toast = Toast.makeText(getBaseContext(),groupPositionID ,Toast.LENGTH_LONG);       
                    toast.show();
                    return false;
                }

            });

this is my SQLhelper function for deleting the selected group from database.

public Cursor GetIngredientsList(){

    return(getReadableDatabase().rawQuery("SELECT _id,Ingredient_name FROM tblIngredients",null));

}

public Cursor DeleteIngredientsList_Item(String index){
        String[] args={index};
        return(getReadableDatabase().rawQuery("DELETE FROM tblIngredients WHERE _id=?",args));

}

The problem I am facing is tha although i am getting the id for the selected group from cursor (i m able to see that as toast) but then, why i am not able to delete that from context menu.

on selecting delete from context menu the following code should execute properly

public boolean onOptionsItemSelected(MenuItem IngredientItem){
    if(IngredientItem.getItemId()==R.id.addIngredient){
        Intent i= new Intent(Ingredients_List.this,Ingredients_Add.class);
        startActivity(i);
        return(true);
    }
    else if (IngredientItem.getItemId()==R.id.deleteIngredient) {

        if(groupPositionID!=null){
              helper.DeleteIngredientsList_Item(groupPositionID);
              return(true);
            }
            else{
                Toast.makeText(getBaseContext(), "Select The Ingredient You want to delete", Toast.LENGTH_LONG).show(); 
            }
    }
    return (super.onOptionsItemSelected(IngredientItem));

} 

I am getting the selected primary key id value from “groupPositionID” variable here.. accurate value is transferred to database raw query also… still not getting what i am expecting

Plz help ASAP I am new to both android and java

sdk information(although not required)

android:versionCode="1"
android:versionName="1.0" 
android:minSdkVersion="8"

Thanks in Advance

Answer 1

public void DeleteIngredientsList_Item(long index){

    String[] args = new String[]{Long.toString(index)};
    Log.v("I am in", "SQLHelper");
    getWritableDatabase().execSQL("DELETE FROM tblIngredients WHERE _id=?",args);

}

i modified this delete code in mysql helper

my function was earlier returning cursor thats why it was not working … meanz in actual query was not getting executed…

rest was ok.. 🙂