问在使用动态列表和文本观察器时，通知数据集更改不起作用

EN

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    mArrayList = new ArrayList();
    mEtSearch = (EditText) findViewById(R.id.et_search);
    mEtText = (EditText) findViewById(R.id.et_item_to_add);
    mBtnAdd = (Button) findViewById(R.id.btn_add);
    mBtnDelete = (Button) findViewById(R.id.btn_delete);
    mLvItems = (ListView) findViewById(R.id.lv_itmes);
    mBtnAdd.setOnClickListener(this);
    mBtnDelete.setOnClickListener(this);
    mAdapter = new ArrayAdapter(this, android.R.layout.simple_list_item_multiple_choice, mArrayList);
    mLvItems.setAdapter(mAdapter);
    mEtSearch.addTextChangedListener(new TextWatcher() {
        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {

        }

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {

        }

        @Override
        public void afterTextChanged(Editable s) {
            String text = mEtSearch.getText().toString().toLowerCase(Locale.getDefault());
            mAdapter.getFilter().filter(text);

        }
    });
}

@Override
public void onClick(View v) {
    switch (v.getId()) {
        case R.id.btn_add:
            if (mEtText.getText().toString().isEmpty()) {
                Toast.makeText(this, "add something to list ", Toast.LENGTH_LONG).show();
            } else {
                mArrayList.add(mEtText.getText().toString());
                mAdapter.notifyDataSetChanged();
                mEtText.setText("");
            }
            break;
        case R.id.btn_delete:
            SparseBooleanArray checkedItemPositions = mLvItems.getCheckedItemPositions();
            int itemCount = mLvItems.getCount();

            for (int i = itemCount - 1; i >= 0; i--) {
                if (checkedItemPositions.get(i)) {
                    mArrayList.remove(i);//This also I tried
                   // mAdapter.remove(mArrayList.get(i));//This also I tried
                }
            }
            checkedItemPositions.clear();
            mAdapter.notifyDataSetChanged();
            break;

    }

}