Question

我有Activity使用NavigationView来显示我的应用菜单。当菜单打开并关闭时，我的应用栏会根据预期从抽屉图标更改为后退箭头。

我有一个场景，我从我的应用程序菜单中单击第1项，然后在我的FrameLayout中打开一个片段，然后我需要单击一个按钮打开另一个片段，替换前一个片段。

应用栏中有2个片段中的抽屉图标，我想在第二个片段上有一个后退箭头，所以我可以返回第一个片段

这是我的MainActivity

public class MainActivity extends SuperActivity {
    @BindView(R.id.nav_view) NavigationView navigationView;
    @BindView(R.id.drawer_layout) DrawerLayout drawerLayout;
    @BindView(R.id.container) FrameLayout frameLayout;
    @BindView(R.id.toolbar) Toolbar toolbar;

    ActionBarDrawerToggle drawerToggle;
    SuperFragment nextFragment;
    FragmentManager fragmentManager;
    String activeName;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ButterKnife.bind(this);
        fragmentManager = getSupportFragmentManager();

        setupView();
        if (savedInstanceState == null) showHome();
    }

    private void setupView() {
        setSupportActionBar(toolbar);

        drawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START);
        drawerToggle = new ActionBarDrawerToggle(this, drawerLayout, toolbar, R.string.drawer_open, R.string.drawer_close);
        drawerLayout.addDrawerListener(drawerToggle);
        drawerLayout.setScrimColor(Color.TRANSPARENT);

        if (navigationView != null) {
            setupDrawerContent(navigationView);
        }

        setupDrawerContent(navigationView);

        navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
            @Override
            public boolean onNavigationItemSelected(@NonNull MenuItem item) {

                drawerLayout.closeDrawer(Gravity.LEFT);
                activeName = item.getTitle().toString();
                toolbar.setTitle(activeName);
                selectDrawerItem(item);

                return false;
            }
        });
    }

    private void setupDrawerContent(NavigationView navigationView) {
        navigationView.setNavigationItemSelectedListener(
                new NavigationView.OnNavigationItemSelectedListener() {
                    @Override
                    public boolean onNavigationItemSelected(MenuItem menuItem) {
                        menuItem.setChecked(true);
                        drawerLayout.closeDrawers();
                        return true;
                    }
                });
    }

    private void showHome() {
        selectDrawerItem(navigationView.getMenu().getItem(0));
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                this.finish();
                return true;
            default:
                return false;
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        return false;
    }

    private void selectDrawerItem(MenuItem menuItem) {
        drawerLayout.closeDrawer(Gravity.LEFT);

        switch (menuItem.getItemId()) {...}
    }

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

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

    private Runnable Logout_Callback = new Runnable() {
        public void run() {
            Toast.makeText(getApplication(),"Log out",Toast.LENGTH_SHORT).show();
        }
    };

    @Override
    public boolean onSupportNavigateUp() {
        onBackPressed();
        return true;
    }
}

从此

延伸

    public class SuperActivity extends AppCompatActivity implements InterfaceHostActivity{

    private SuperFragment selectedFragment;

    // Navigation adapter
    public NavigationListAdapter mNavigationAdapter;

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

    }

    public void replaceFragment(SuperFragment fragment, boolean addToBackStack) {
        replaceFragment(fragment, addToBackStack, R.id.container);
    }

    public void replaceFragment(SuperFragment fragment, boolean addToBackStack, int layout) {
        try {
            FragmentManager manager = getSupportFragmentManager();
            if (fragment.isMainFragment) {
                manager.popBackStack(null, FragmentManager.POP_BACK_STACK_INCLUSIVE);
            }

            String backStateName = ((Object) fragment).getClass().getName();
            boolean fragmentPopped = manager.popBackStackImmediate(backStateName, 0);

            if (!fragmentPopped) {

                FragmentTransaction ft = manager.beginTransaction();
                ft.replace(layout, fragment, backStateName);
                ft.setTransition(FragmentTransaction.TRANSIT_NONE);

                if (addToBackStack)
                    ft.addToBackStack(backStateName);

                ft.commit();
            }

            getSupportFragmentManager().executePendingTransactions();

        } catch (Exception e) {
            LogManager.logException(e);
        }
    }

    @Override
    public void setSelectedFragment(SuperFragment fragment) {
        this.selectedFragment = fragment;
    }

    @Override
    public void popBackStack() {
        getSupportFragmentManager().popBackStackImmediate();
    }

    @Override
    public void popBackStackUntilTag(String tag) {
        getSupportFragmentManager().popBackStackImmediate(tag, FragmentManager.POP_BACK_STACK_INCLUSIVE);
    }

    @Override
    public void addFragment(SuperFragment fragment, boolean addToBackStack) {

        try {
            String backStateName = ((Object) fragment).getClass().getName();
            String fragmentTag = backStateName;

            FragmentTransaction ft = getSupportFragmentManager().beginTransaction();

            ft.replace(R.id.container, fragment, fragmentTag);
            ft.setTransition(FragmentTransaction.TRANSIT_NONE);
            if (addToBackStack)
                ft.addToBackStack(backStateName);
            ft.commit();
        } catch (Exception e) {
            LogManager.logException(e);
        }
    }

    @Override
    public void addMultipleFragments(SuperFragment[] fragments) {

    }

    @Override
    public void onBackPressed() {
        boolean eventConsumed = false;
        if (selectedFragment != null) {
            eventConsumed = eventConsumed || selectedFragment.onBackPressed();
        }
        if (!eventConsumed) {
            super.onBackPressed();
        }
    }

    @Override
    protected void onStart() {
        super.onStart();
    }

    @Override
    protected void onStop() {
        super.onStop();
    }
}

和我的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"
    tools:context="pt.sibs.android.mpos.activities.MainActivity">

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

        <FrameLayout
            android:id="@+id/container"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_marginTop="?attr/actionBarSize" />

        <include layout="@layout/toolbar" />
    </RelativeLayout>

    <android.support.design.widget.NavigationView
        android:id="@+id/nav_view"
        android:layout_height="match_parent"
        android:layout_width="wrap_content"
        android:layout_gravity="start"
        android:fitsSystemWindows="true"
        app:customTypeface="@string/font_lato_light"
        android:background="@color/menuBG"
        android:layout_marginTop="?attr/actionBarSize"
        app:itemTextColor="@color/drawer_text_color_selector"
        app:itemTextAppearance="@style/TextViewBody"
        app:itemIconTint="@color/menu_icon_selector"
        app:itemBackground="@drawable/menu_item_bg"
        app:menu="@menu/drawer_view"/>
</android.support.v4.widget.DrawerLayout>

Answer 1

您可以使用界面

科特林

Interface：

interface IChangeFragmentListener {
    fun updateToolbar(showBackButton: Boolean = false)
}

在Interface中实施MainActivity：

class MainActivity : IChangeFragmentListener {

    private lateinit var toggle: ActionBarDrawerToggle

    ...

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        decorateApplication()

        setSupportActionBar(toolbar)
        if (supportActionBar != null) {
            supportActionBar?.setDisplayShowTitleEnabled(false)
            supportActionBar?
               .setDisplayHomeAsUpEnabled(true)
         }

        toggle = ActionBarDrawerToggle(
            this,
            drawer_layout,
            toolbar as Toolbar,
            R.string.navigation_drawer_open,
            R.string.navigation_drawer_close
        )
      ...
    }

    override fun updateToolbar(showBackButton: Boolean) {
        //remove hamburger icon and show arrow icon because
        //setDisplayHomeAsUpEnabled in actionbar o toolbar is true
        toggle.isDrawerIndicatorEnabled = !showBackButton
        toggle.setToolbarNavigationClickListener {
            if (showBackButton) onBackPressed()
        }
    }
 ...   
}

在Fragment中附加接口，然后在OnResume上调用它：

open class SomeFragment : Fragment() {

    var iChangeFragmentListener: IChangeFragmentListener? = null

    override fun onAttach(context: Context) {
        super.onAttach(context)
        try {
            if (context is IChangeFragmentListener)
                iChangeFragmentListener = context
        } catch (ex: Exception) {
            Timber.e(ex)
        }
    }

    override fun onResume() {
        super.onResume()
        iChangeFragmentListener?.updateToolbar(true)
    }

   ...
}

使用NavigationView时，从抽屉图标更改为箭头

1 个答案: