Hapus kegiatan

 private void deletePet() {
        // Only perform the delete if this is an existing pet.
        if (mCurrentUri != null) {
            // Call the ContentResolver to delete the pet at the given content URI.
            // Pass in null for the selection and selection args because the mCurrentPetUri
            // content URI already identifies the pet that we want.
            int rowsDeleted = getContentResolver().delete(mCurrentUri, null, null);

            // Show a toast message depending on whether or not the delete was successful.
            if (rowsDeleted == 0) {
                // If no rows were deleted, then there was an error with the delete.
                Toast.makeText(this, "Kegiatan Gagal dihapus",
                        Toast.LENGTH_SHORT).show();
            } else {
                // Otherwise, the delete was successful and we can display a toast.
                Toast.makeText(this, "Kegiatan Berhasil dihapus",
                        Toast.LENGTH_SHORT).show();
            }
        }

        // Close the activity
        finish();
    }