Android DrawerLayout不顯示正確的指示器圖標

Question

我試圖使用新的DrawerLayout作爲列表。問題是雖然我設置了抽屜監聽器，但操作欄上的指示器仍然是箭頭圖標，而不是我打算繪製的3線圖標。以下是OnCreate功能：

public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_front_page); 

    // Swiping Pager set up 
    mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager()); 

    mViewPager = (ViewPager) findViewById(R.id.pager); 
    mViewPager.setAdapter(mSectionsPagerAdapter); 

    // Sliding Drawer set up 
    mHabitContract = new HabitsContract(this); 
    mDrawerLayout = (DrawerLayout) findViewById(R.id.front_page_layout); 
    mDrawerList = (ListView) findViewById(R.id.habit_list); 
    mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START); 
    mDrawerList.setAdapter(new HabitAdapter(mHabitContract.GetHabitItems(), this)); 

    // Fixme: Indicator image doesn't show up 
    mDrawerToggle = new ActionBarDrawerToggle(
      this,     /* host Activity */ 
      mDrawerLayout,   /* DrawerLayout object */ 
      R.drawable.ic_navigation_drawer, /* nav drawer image to replace 'Up' caret */ 
      R.string.drawer_open, /* "open drawer" description for accessibility */ 
      R.string.drawer_close /* "close drawer" description for accessibility */ 
    ) { 
     public void onDrawerClosed(View view) { 
      //getActionBar().setTitle(mTitle); 
      invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu() 
     } 

     public void onDrawerOpened(View drawerView) { 
      //getActionBar().setTitle(mDrawerTitle); 
      invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu() 
     } 
    }; 
    mDrawerLayout.setDrawerListener(mDrawerToggle); 

    // Action Bar set up 
    getActionBar().setDisplayHomeAsUpEnabled(true); 
    getActionBar().setHomeButtonEnabled(true); 
    getActionBar().setDisplayShowHomeEnabled(true); 
} 

任何人都可以幫忙嗎？

更新：我發現了這個問題。我添加了onPostCreate函數如下，現在它工作。

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

Answer 1

您需要syncState()打電話給你的ActionBarDrawerToggle對象從onPostCreate()

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

Answer 2

您正在使用的圖標稱爲「ic_navigation_drawer」。您可以檢查它是否是正確的，因爲谷歌在官方指南（http://developer.android.com/training/implementing-navigation/nav-drawer.html）中提供的圖標稱爲「ic_drawer」。

Answer 3

還要檢查carefuly如果定製ActionBar主題與條件android:displayOptions=showTitle定義到您的項目在style.xml文件。像這樣：

<style name="OrangeBar" parent="@android:style/Widget.Holo.ActionBar"> 
    <item name="android:displayOptions">showTitle</item> 
    ... 
</style> 

它可能會損壞抽屜指示器。爲了避免這種情況，在android:displayOptions添加showHome：

<item name="android:displayOptions">showHome|showTitle</item> 

Answer 4

對於那些誰正在尋找這樣或來到這裏尋找一個答案：你必須使用DrawerToggle support.v7。按照我的使用方法：

drawerToggle = new ActionBarDrawerToggle(this, drawerLayout, R.string.drawer_opened, R.string.drawer_closed){ 
     public void onDrawerClosed(View view){ 
      //actionBar.setTitle(mTitle); 
      invalidateOptionsMenu(); // crea la llamada para onPrepareOptionsMenu 
     } 
     public void onDrawerOpened(View view){ 
      //actionBar.setTitle(mDrawerTitle); 
      invalidateOptionsMenu(); // crea la llamda para onPrepareOptionsMenu 
     } 
    }; 

這工作正常，並有一個動畫，巖！