與ViewModel ViewPager綁定問題

Question

我正在使用ViewPager實現MvvmCross 4.0.0-beta5中的選項卡。但是，ViewModel的EditText綁定屬性始終爲空。我也嘗試更新到MvvmCross 4.0.0-beta7，但沒有運氣。

這裏是我的ViewPager

<android.support.design.widget.AppBarLayout 
    android:id="@+id/appbar" 
    android:orientation="vertical" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent"> 
    <include 
     android:id="@+id/mspManagerToolbar" 
     layout="@layout/mspmanagertoolbar" /> 
    <android.support.design.widget.TabLayout 
     android:id="@+id/tabs" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     android:paddingLeft="16dp" 
     local:tabGravity="fill" 
     local:tabMode="scrollable" /> 
    <android.support.v4.view.ViewPager 
     android:id="@+id/viewpager" 
     android:layout_width="match_parent" 
     android:layout_height="0dp" 
     android:layout_weight="1" 
     local:layout_behavior="@string/appbar_scrolling_view_behavior" /> 
</android.support.design.widget.AppBarLayout> 

這裏是我的標籤視圖

<EditText 
    ... 
    local:MvxBind="Text Title" /> 

以上的EditText約束力不工作。標題始終爲空。

<EditText 
    ... 
    local:MvxBind="Text User.Title" /> 

上面的EditText綁定工作完美。 User.Title獲得正確的價值。

這裏ViewPagerView.cs代碼

public class CustomerDetailView : MvxCachingFragmentCompatActivity<CustomerDetailViewModel> 
{ 
    protected override void OnCreate(Bundle bundle) 
    { 
     base.OnCreate(bundle); 

     SetContentView(Resource.Layout.CustomerDetailView); 

     // Use toolbar as action bar 
     var toolbar = FindViewById<Toolbar>(Resource.Id.mspManagerToolbar); 

     if (toolbar != null) 
     { 
      // Toolbar will now take on default actionbar characteristics 
      SetSupportActionBar(toolbar); 

     } 

     // View Pager 
     var viewPager = FindViewById<ViewPager>(Resource.Id.viewpager); 
     if (viewPager != null) 
     { 
      // Add tabs in view pager 
      var fragments = new List<MvxFragmentStatePagerAdapter.FragmentInfo> 
      { 
       new MvxFragmentStatePagerAdapter.FragmentInfo(TAB_DETAIL, typeof(Tab_CustomerDetail), typeof(CustomerDetailViewModel)), 
       new MvxFragmentStatePagerAdapter.FragmentInfo(TAB_CONTACT, typeof(Tab_CustomerContact), typeof(CustomerDetailViewModel)), 
       new MvxFragmentStatePagerAdapter.FragmentInfo(TAB_LOCATION, typeof(Tab_CustomerLocation), typeof(CustomerDetailViewModel)), 
       new MvxFragmentStatePagerAdapter.FragmentInfo(TAB_CONTRACT, typeof(Tab_CustomerContract), typeof(CustomerDetailViewModel))     
      }; 
      viewPager.Adapter = new MvxFragmentStatePagerAdapter(this, SupportFragmentManager, fragments); 
     } 

     var tabLayout = FindViewById<TabLayout>(Resource.Id.tabs); 
     tabLayout.SetupWithViewPager(viewPager); 
    } 
} 

這是我的代碼片段

[Register("app.droid.views.fragments.Tab_CustomerDetail")] 
public class Tab_CustomerDetail : MvxFragment 
{   

    #region Public Method 

    /// <summary> 
    /// tab customer detail view 
    /// </summary> 
    /// <param name="inflater"></param> 
    /// <param name="container"></param> 
    /// <param name="savedInstanceState"></param> 
    /// <returns></returns> 
    public override View OnCreateView(Android.Views.LayoutInflater inflater, Android.Views.ViewGroup container, Android.OS.Bundle savedInstanceState) 
    { 
     var ignored = base.OnCreateView(inflater, container, savedInstanceState); 

     var view = this.BindingInflate(Resource.Layout.frg_tab_CustomerDetail, null); 


     return view; 
    } 

    #endregion 

} 

這裏是視圖模型屬性

public string Title 
{ 
    get 
    { 
     return (title); 
    } 
    set 
    { 
     if (value != title) 
     { 
      title = value; 

      RaisePropertyChanged(() => this.Title); 
     } 
    } 
} 

public User User 
{ 
    get 
    { 
     return (repositoryService.User); 
    } 
    set 
    { 
     repositoryService.User = value; 
     RaisePropertyChanged(() => User); 
    } 
} 

Title屬性越來越空，User.Title正在完善。那麼請讓我知道我哪裏錯了？

Answer 1

問題是我從活動中保存我的數據，所以我沒有獲得視圖的價值。因爲對於每個片段，它都創建視圖模型的新實例，因爲沒有獲得更新的視圖值。現在我從片段中保存數據，現在我在視圖模型中獲取所有視圖值。

Answer 2

更改屬性是否修復它？

public string Title 
{ 
    get 
    { 
     return title; 
    } 
    set 
    { 
     title = value; 
     RaisePropertyChanged(() => this.Title); 
    } 
}