android - 抽屉指示灯不显示

Question

我无法显示抽屉指示器。目前，根据 actionBar 设置，屏幕左上角没有任何内容或“<”。但我想要 Nagivation 抽屉的抽屉指示器。

我用:

• v4.widget.DrawerLayout
• v7.app.ActionBarDrawerToggle
• 但 android.app.ActionBar(不支持 7 个)。

这是代码 fragment :

@Override
protected void onCreate(Bundle savedInstanceState)
{
    actionBar.setDisplayHomeAsUpEnabled(true); 
    actionBar.setHomeButtonEnabled(true);
    actionBar.setDisplayShowHomeEnabled(true);
    //I tried all combinations unsuccessfully
    ....
    drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
    drawerLV = (ListView) findViewById(R.id.left_drawer);
    drawer_Linearlayout = (LinearLayout) findViewById(R.id.drawer_Linearlayout);

    drawerLV.setAdapter(new ArrayAdapter<String>(
            this,
            R.layout.layout_main_drawer_list_item,
            mDrawerItems));

    drawerLV.setOnItemClickListener(new ListView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            selectItem(position);
        }
    });

    drawerToggle = new ActionBarDrawerToggle(this, drawer, R.string.drawer_open,R.string.drawer_close) {
        @Override
        public void onDrawerClosed(View view) {
            actionBar.setTitle(mTitle);
    }
        @Override
        public void onDrawerOpened(View drawerView) {
            actionBar.setTitle(mDrawerTitle);
        }
    };
    drawerToggle.setDrawerIndicatorEnabled(true);
    drawer.setDrawerListener(drawerToggle);
}

Answer 1

我最终解决了我的问题。我忘了在我的 Activity 中添加以下回调:

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

顺便说一句，Lollipop 升级 v7.app.ActionBarDrawerToggle 在抽屉导航打开或关闭时添加了一个不错的效果。我推荐它。