android - 抽屉导航 : no more animation on drawer icon when setting drawer listener

Question

<-- 抽屉图标

如果您使用 android studio 创建一个带有抽屉导航的项目，当您打开/关闭抽屉时，抽屉图标会有流畅的动画效果。

如果我向我的抽屉布局添加一个抽屉监听器，则不再有动画，抽屉图标也不再改变:

DrawerLayout dl = (DrawerLayout) findViewById(R.id.drawer_layout);
    dl.setDrawerListener(new ActionBarDrawerToggle(this, dl,R.drawable.ic_drawer,R.string.navigation_drawer_open,R.string.navigation_drawer_close));

我试图覆盖 ActionBarDrawerToggle 的方法以添加对 syncState() 的调用。

   DrawerLayout dl = (DrawerLayout)findViewById(R.id.drawer_layout);

    mDrawerToggle = new ActionBarDrawerToggle(this, dl,
            R.drawable.ic_drawer, R.string.drawer_open, R.string.drawer_close) {

        @Override
        public void onDrawerSlide(View drawerView, float slideOffset) {
            super.onDrawerSlide(drawerView, slideOffset);
            mDrawerToggle.syncState();
        }

        @Override
        public void onDrawerStateChanged(int newState) {
            super.onDrawerStateChanged(newState);
            mDrawerToggle.syncState();
        }

        public void onDrawerClosed(View view) {
            super.onDrawerClosed(view);
            mDrawerToggle.syncState();
        }

        /** Called when a drawer has settled in a completely open state. */
        public void onDrawerOpened(View drawerView) {
            super.onDrawerOpened(drawerView);
            mDrawerToggle.syncState();
        }
    };
    dl.setDrawerListener(mDrawerToggle);

现在，当抽屉打开时，我有一个小图标，然后当抽屉关闭时它会切换到一个大图标，但我没有流畅的动画。

有人知道如何获得流畅的动画吗？

Answer 1

尝试放置最后两个监听器缺少的 @Override 注释，并删除所有 syncState() 调用。从 Activity 的 onPostCreate 调用 syncState():

@Override
protected void onPostCreate(Bundle savedInstanceState) {
    super.onPostCreate(savedInstanceState);
    // Sync the toggle state after onRestoreInstanceState has occurred.
    mDrawerToggle.syncState();
}