Androidナビゲーションドロワーアイコンが機能しません

Question

私は作業用のナビゲーションドロワーを持っていましたが、ツールバーを変更したところ、ナビゲーションドロワーのアイコンが機能しなくなりました。引き出しを引っ張ってから再び動作します。これは、関連するコードです：

MainActivity.java

//Drawer and fragments variables 
private FragmentManager fragmentManager; 
private ActionBarDrawerToggle toggle; 
private DrawerLayout drawer; 

//Searchbar variables 
private Toolbar toolbar, searchtollbar; 
private Menu search_menu; 
private MenuItem item_search; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    //Setup toolbar 
    toolbar = (Toolbar) findViewById(R.id.toolbar); 
    setSupportActionBar(toolbar); 
    setSearchtollbar(); 

    //Setup navigationdrawer 
    drawer = (DrawerLayout) findViewById(R.id.drawer_layout); 
    toggle = new ActionBarDrawerToggle(this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close); 
    drawer.addDrawerListener(toggle); 
    NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view); 
    navigationView.setNavigationItemSelectedListener(this); 
    navigationView.getMenu().getItem(0).setChecked(true); 

    //Setup fragments 
    fragmentManager = getSupportFragmentManager(); 
    try{ 
     fragmentManager.beginTransaction().replace(R.id.container, HomeFragment.class.newInstance()).commit(); 
    }catch(Exception e){ 
     handleError(e); 
    } 
} 

@Override 
public void onBackPressed() { 
    drawer = (DrawerLayout) findViewById(R.id.drawer_layout); 
    if (drawer.isDrawerOpen(GravityCompat.START)) { 
     drawer.closeDrawer(GravityCompat.START); 
    } else { 
     super.onBackPressed(); 
    } 
} 

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

@Override 
protected void onPostCreate(Bundle savedInstanceState){ 
    super.onPostCreate(savedInstanceState); 
    toggle.syncState(); 
} 

@Override 
public void onConfigurationChanged(Configuration newConfig) { 
    super.onConfigurationChanged(newConfig); 
    toggle.onConfigurationChanged(newConfig); 
} 

@Override 
public boolean onOptionsItemSelected(MenuItem item) { 
    // Handle action bar item clicks here. The action bar will 
    // automatically handle clicks on the Home/Up button, so long 
    // as you specify a parent activity in AndroidManifest.xml. 
    //noinspection SimplifiableIfStatement 
    Log.i("TAG", "Item clicked: "+item.getItemId()); 
    if (toggle.onOptionsItemSelected(item)) { 
     return true; 
    } 
    switch(item.getItemId()){ 
     case R.id.action_settings:{ 
      Intent intent = new Intent(this, SettingsActivity.class); 
      startActivity(intent); 
      return true; 
     } 
    } 
    return super.onOptionsItemSelected(item); 
} 

@Override 
public boolean onNavigationItemSelected(MenuItem item) { 
    // Handle navigation view item clicks here. 
    int id = item.getItemId(); 
    Log.i("TAG", "Navigation item clicked: " + id); 
    Class fragmentClass; 
    Fragment fragment = null; 

    switch(id) { 
     ... 
    } 

    try { 
     fragment = (Fragment) fragmentClass.newInstance(); 
    } catch (Exception e) { 
     handleError(e); 
    } 

    fragmentManager = getSupportFragmentManager(); 
    fragmentManager.beginTransaction().replace(R.id.container, fragment).commit(); 
    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout); 
    drawer.closeDrawer(GravityCompat.START); 
    return true; 
} 

main_activity.xml

<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:app="http://schemas.android.com/apk/res-auto" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:id="@+id/drawer_layout" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:fitsSystemWindows="true" 
    tools:openDrawer="start"> 

    <RelativeLayout 
     android:layout_width="match_parent" 
     android:layout_height="match_parent"> 
     <include 
      android:id="@+id/toolbar" 
      layout="@layout/app_bar_main"/> 
     <include layout="@layout/app_bar_main_search" 
      android:visibility="invisible"/> 
     <include 
      layout="@layout/main_layout" 
      android:layout_width="match_parent" 
      android:layout_height="match_parent" 
      android:layout_below="@id/toolbar"/> 
    </RelativeLayout> 

    <android.support.design.widget.NavigationView 
     android:id="@+id/nav_view" 
     android:layout_width="wrap_content" 
     android:layout_height="match_parent" 
     android:layout_gravity="start" 
     android:fitsSystemWindows="true" 
     android:visibility="gone" 
     app:headerLayout="@layout/nav_header_main" 
     app:menu="@menu/activity_main_drawer" /> 

</android.support.v4.widget.DrawerLayout> 

は今私の質問は以下のとおりです。

• なぜハンバーガーのアイコンは機能しません。初めて？
• ナビゲーション用の引き出しを引き出した後に動作が開始するのはなぜですか？

ありがとうございます。

Answer 1

引き出しリスナーを設定した後に、このコードの同期トグル追加し

drawer.addDrawerListener(toggle); 
toggle.syncState(); 

Answer 2

使用を確認してください。

 
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
       this, mDrawerLayout, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close); 

toggle.setDrawerIndicatorEnabled(false); //disable "hamburger to arrow" drawable 
     toggle.setHomeAsUpIndicator(R.drawable.menu); //set your own 

     // setting click listener on hamburger icon 
     toolbar.setNavigationOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View v) { 
       mDrawerLayout.openDrawer(Gravity.START); 
       } 
      } 
     }); 

     // setting listerner on drawer 
     mDrawerLayout.addDrawerListener(toggle); 
     toggle.syncState();