如何将设置菜单中的数据输入到MainActivity.java文件中以调整文本视图窗口中的文本大小？

private int textSize;

<EditText
    android:id="@+id/editTextTextSize"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:inputType="number"
    android:hint="请输入文本大小"
    />

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    int id = item.getItemId();

    if (id == R.id.action_settings) {
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle("设置");
        builder.setView(R.layout.dialog_settings);
        builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                EditText editTextTextSize = ((AlertDialog) dialog).findViewById(R.id.editTextTextSize);
                String textSizeStr = editTextTextSize.getText().toString();
                if (!TextUtils.isEmpty(textSizeStr)) {
                    textSize = Integer.parseInt(textSizeStr);
                    adjustTextSize();
                }
            }
        });
        builder.setNegativeButton("取消", null);
        builder.show();
        return true;
    }

    return super.onOptionsItemSelected(item);
}

private void adjustTextSize() {
    TextView textView = findViewById(R.id.textView);
    textView.setTextSize(textSize);
}