android - 向上导航(操作栏的后退箭头)不适用于 fragment

Question

我将抽屉布局作为 Activity 的基本布局，我正在替换此抽屉布局内框架上的两个 fragment 。第一个 fragment 未添加到 fragment 的返回堆栈中。我在我的 Activity 中显示汉堡包图标(我还想要我的第一个 fragment 中的抽屉菜单)。在第二个 fragment 中，我通过 mActionBarDrawerToggle.setDrawerIndicatorEnabled(false) 禁用了汉堡包图标，并使用 actionBar.setDisplayHomeAsUpEnabled(true) 启用了后退按钮。

在第一个 fragments onResume 中，我通过 mActionBarDrawerToggle.setDrawerIndicatorEnabled(true)` 启用了汉堡包图标，这样当用户从第二个 fragment 按下后退按钮(硬件和操作栏的向上按钮)时，用户将返回到第一个 fragment 和汉堡包图标将被启用。一切正常，只是我无法从第二个 fragment 操作栏后退按钮返回。我无法点击它。下面是我的代码:-

Activity 代码

if (Utility.isLargeScreen(this))
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
    else
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);

    mHiddenGemsApplication = (HiddenGemsApplication) getApplication();

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_home);
    initViews();

    setSupportActionBar(mToolbar);
    ActionBar actionBar = getSupportActionBar();
    if (actionBar != null) {
        actionBar.setDisplayShowTitleEnabled(false);
        actionBar.setDisplayHomeAsUpEnabled(true);
    }
    mTextViewActionBarTitle.setText(getString(R.string.app_name));

    mActionBarDrawerToggle = new ActionBarDrawerToggle(HomeActivity.this, mDrawerLayout, mToolbar, R.string.open_drawer, R.string.close_drawer) {

        @Override
        public void onDrawerClosed(View drawerView) {
            super.onDrawerClosed(drawerView);
        }

        @Override
        public void onDrawerOpened(View drawerView) {
            super.onDrawerOpened(drawerView);
        }
    };

    mDrawerLayout.setDrawerListener(mActionBarDrawerToggle);

    mActionBarDrawerToggle.syncState();

    mFragmentManager = getSupportFragmentManager();

    replaceFragment(new CategoryFragment(), getString(R.string.app_name), CategoryFragment.TAG);

 @Override
public void onBackPressed() {

    if (mDrawerLayout.isDrawerOpen(GravityCompat.START)) {
        mDrawerLayout.closeDrawers();
        return;
    }
    super.onBackPressed();
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {

    switch (item.getItemId()) {
        case android.R.id.home:
            if (mFragmentManager.getBackStackEntryCount() > 0) {
                mFragmentManager.popBackStack();
            }
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}

 public void replaceFragment(Fragment fragment, String actionBarTitle, String tag) {

    if (mFragmentManager == null)
        return;

    FragmentTransaction fragmentTransaction = mFragmentManager.beginTransaction();
    fragmentTransaction.replace(R.id.content_frame, fragment, tag);
    if (!tag.equals(CategoryFragment.TAG))
        fragmentTransaction.addToBackStack(tag);
    fragmentTransaction.commit();

    setActionBarTitle(actionBarTitle);
}

public void setActionBarTitle(String actionBarTitle) {
    if (!TextUtils.isEmpty(actionBarTitle))
        mTextViewActionBarTitle.setText(actionBarTitle);
}

public void setDrawerIndicatorEnabled(boolean value) {
    if (mActionBarDrawerToggle != null) {
        mActionBarDrawerToggle.setDrawerIndicatorEnabled(value);
    }
}

Activity XML

<?xml version="1.0" encoding="utf-8"?>
<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:context="nirvaniclabs.com.hiddengems.activities.HomeActivity">

<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <include
        android:id="@+id/toolbarlayout"
        layout="@layout/toolbar_layout" />

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

<android.support.design.widget.NavigationView
    android:id="@+id/navigation"
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    android:layout_gravity="start"
    app:menu="@menu/navigation_items" />

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

第一个 fragment :-

 private Button mButtonTemp;
private AppCompatActivity mActivity;
public static String TAG = "CategoryFragment";

public CategoryFragment() {
    // Required empty public constructor
}

@Override
public void onAttach(Context context) {
    super.onAttach(context);

    if (context instanceof Activity)
        mActivity = (AppCompatActivity) context;
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    View viewGroup = inflater.inflate(R.layout.fragment_category, container, false);
    initViews(viewGroup);

    mButtonTemp.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            ((HomeActivity) mActivity).replaceFragment(new TripListFragment(), "Trip Fragment", TripListFragment.TAG);
        }
    });

    return viewGroup;
}

private void initViews(View viewGroup) {
    mButtonTemp = (Button) viewGroup.findViewById(R.id.btn_temp);
}

@Override
public void onResume() {
    super.onResume();
    ((HomeActivity) mActivity).setDrawerIndicatorEnabled(true);
    ((HomeActivity) mActivity).setActionBarTitle(getString(R.string.app_name));
}

第二个 fragment

  private AppCompatActivity mActivity;
public static String TAG = "TripListFragment";

public TripListFragment() {
    // Required empty public constructor
}

@Override
public void onAttach(Context context) {
    super.onAttach(context);
    if (context instanceof Activity)
        mActivity = (AppCompatActivity) context;
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setHasOptionsMenu(true);
    ActionBar actionBar = mActivity.getSupportActionBar();
    if (actionBar != null) {
        actionBar.setDisplayShowTitleEnabled(false);
        actionBar.setDisplayHomeAsUpEnabled(true);
    }
}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    return inflater.inflate(R.layout.fragment_trip_list, container, false);
}


@Override
public void onResume() {
    super.onResume();
    ((HomeActivity) mActivity).setDrawerIndicatorEnabled(false);
}

此外，当我在第二个 fragment 中时，我可以滑动并查看抽屉菜单。我不想要这种行为，抽屉菜单应该只在 fragment 1 中打开。

如果我的代码有任何问题，请告诉我。

Answer 1

终于有了答案。在我的场景中，我通过 mActionBarDrawerToggle.setDrawerIndicatorEnabled(false); 禁用抽屉指示器，并且由于此导航图标点击被禁用。要启用此功能，我必须将 ToolbarNavigationClickListener 添加到 ActionBarDrawerToggle，这将启用导航图标点击。

下面是我的工作代码:-

mActionBarDrawerToggle.setToolbarNavigationClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onBackPressed();
            }
        });

Refer this link for more clarification