在Android上实现NavDrawer

Question

我即将在android上使用Mvvmcross和Xamarin（在c＃中）实现NavDrawer，但我有点担心让我的HomeView模型看起来像这样：https://github.com/jamesmontemagno/Xam.NavDrawer/blob/master/Mvx/MvxSample/ViewModels/HomeViewModel.cs。

如何在MS平台上使用这种视图模型，我可能会有一个panarama或者与布局数据非常不同的东西。

对于不支持NavDrawer类型体验的平台，我应该有一个单独的home viewmodel吗？

Answer 1

导航实施API级> 7

NavDrawerProject/RES /值/ strings.xml中

<resources> 
    <string-array name="pages_array"> 
     <item>Home</item> 
     <item>Trending</item> 
     <item>Profile</item> 
    </string-array> 
<resources> 

NavDrawerProject/RES /布局/ activity_main.xml中

<android.support.v4.widget.DrawerLayout 
    xmlns:android="http://schemas.android.com/apk/res/android" 
    android:id="@+id/drawer_layout" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent"> 

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

<ListView 
    android:id="@+id/left_drawer" 
    android:layout_width="240dp" 
    android:layout_height="match_parent" 
    android:layout_gravity="start" 
    android:choiceMode="singleChoice" 
    android:divider="@android:color/transparent" 
    android:dividerHeight="0dp" 
    android:background="@color/drawer_bg" 
    android:paddingTop="?attr/actionBarSize"/> 

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

NavDrawerProject/src/MainActivity.java

public class MainActivity extends ActionBarActivity { 
// navigation drawer 
private DrawerLayout mDrawerLayout; 
private ListView mDrawerList; 
private ActionBarDrawerToggle mDrawerToggle; 

private CharSequence mDrawerTitle; 
private CharSequence mTitle; 
private String[] mPageTitles; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    // setting up navigation drawer 
    mTitle = mDrawerTitle = getTitle(); 
    mPageTitles = getResources().getStringArray(R.array.pages_array); 
    mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout); 

    mDrawerList = (ListView) findViewById(R.id.left_drawer); 

    // set a custom shadow that overlays the main content when the drawer 
    // opens 
    mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, 
      GravityCompat.START); 
    // set up the drawer's list view with items and click listener 
    mDrawerList.setAdapter(new ArrayAdapter<String>(this, 
      R.layout.drawer_list_item, mPageTitles)); 
    mDrawerList.setOnItemClickListener(new DrawerItemClickListener()); 
    // enable ActionBar app icon to behave as action to toggle nav drawer 
    getSupportActionBar().setDisplayHomeAsUpEnabled(true); 
    getSupportActionBar().setHomeButtonEnabled(true); 

    // ActionBarDrawerToggle ties together the the proper interactions 
    // between the sliding drawer and the action bar app icon 
    mDrawerToggle = new ActionBarDrawerToggle(this, /* host Activity */ 
    mDrawerLayout, /* DrawerLayout object */ 
    R.drawable.ic_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 */ 
    ) { 
     // TODO find out if stray { 
     public void onDrawerClosed(View view) { 
      getSupportActionBar().setTitle(mTitle); 
      supportInvalidateOptionsMenu(); // creates call to 
              // onPrepareOptionsMenu() 
     } 

     public void onDrawerOpened(View drawerView) { 
      getSupportActionBar().setTitle(mDrawerTitle); 
      supportInvalidateOptionsMenu(); // creates call to 
              // onPrepareOptionsMenu() 
     } 
     // TODO find out if stray 
    }; 
    mDrawerLayout.setDrawerListener(mDrawerToggle); 
} 

@Override 
public boolean onPrepareOptionsMenu(Menu menu) { 
    // If the nav drawer is open, hide action items related to the content 
    // view 
    boolean drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerList); 
    menu.findItem(R.id.action_settings).setVisible(!drawerOpen); 
    return super.onPrepareOptionsMenu(menu); 
} 

@Override 
public boolean onOptionsItemSelected(MenuItem item) { 
    // The action bar home/up action should open or close the drawer. 
    // ActionBarDrawerToggle will take care of this. 
    if (mDrawerToggle.onOptionsItemSelected(item)) { 
     return true; 
    } 
} 

/* The click listener for ListView in the navigation drawer */ 
private class DrawerItemClickListener implements 
     ListView.OnItemClickListener { 
    @Override 
    public void onItemClick(AdapterView<?> parent, View view, int position, 
      long id) { 
     selectItem(position); 
    } 
} 

private void selectItem(int position) { 
    // update the main content by replacing fragments 
    Fragment fragment; 
    switch (position) { 
    case 0: 
     fragment = new HomePageFragment(); 
     break; 
    case 1: 
     fragment = new TrendingPageFragment(); 
     break; 
    case 2: 
     fragment = new ProfilePageFragment(); 
     break; 
    default: 
     fragment = new HomePageFragment(); 
     break; 
    } 
    FragmentManager fragmentManager = getSupportFragmentManager(); 
    FragmentTransaction transaction = fragmentManager.beginTransaction(); 
    transaction.replace(R.id.content_main, fragment); 
    transaction.addToBackStack(null); 
    transaction.commit(); 
    // update selected item and title, then close the drawer 
    mDrawerList.setItemChecked(position, true); 
    setTitle(mPageTitles[position]); 
    mDrawerLayout.closeDrawer(mDrawerList); 

} 

@Override 
public void setTitle(CharSequence title) { 
    mTitle = title; 
    getSupportActionBar().setTitle(mTitle); 
} 
} 

Answer 2

要在旧版Android上使用导航抽屉，您应该查看支持库。 http://components.xamarin.com/view/xamandroidsupportv7appcompat