问如何仅用按钮打开抽屉布局？

EN

drawer.setDrawerLockMode(DrawerLayout.LOCK_MODE_LOCKED_CLOSED);

  <FrameLayout
        android:id="@+id/content_frame"
        android:layout_width="match_parent"
        android:layout_height="match_parent" >
    </FrameLayout>

   //For me a better way in avoiding a `null pointer` in getting the DrawerLayout
   final DrawerLayout drawer = (DrawerLayout) getActivity().findViewById(R.id.drawer_layout);
   btn.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                            //Opens the Drawer
                drawer.openDrawer(Your View, Usually a ListView);
            }

                return false;
        });

drawer.closeDrawer(Your View, Usually a ListView);

 mButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            drawer.openDrawer(navigationView);

        }
    });