Question

我在viewmodel中有五个对象如下，我想拥有相同数量的片段。目前，我已经硬编码了五个碎片。

是否有办法从viewmodel获取对象的数量并将其传递给视图以使其模块化而不是硬编码。我正在使用mvvm模式。

ViewModel类

NAMES     VALUE1     VALUE2     VALUE3
john      1          2           3
bro       4          5           6
guy       7          8           9

查看课程

public RecyclerViewModel()
 {
    Items = new ObservableCollection<ListItem> {
        new ListItem { Title = "A" },
        new ListItem { Title = "B" },
        new ListItem { Title = "C" },
        new ListItem { Title = "D" },
        new ListItem { Title = "E" }
    };
 }

Answer 1

Items = new ObservableCollection<ListItem> {
                new ListItem { StaticClass.a[StaticClass.index < StaticClass.a.Length ? StaticClass.Index : StaticClass.a.Length -1] }
            };
StaticClass.Index++;

所以在你的构造函数中：

var fragments = new List<MvxFragmentPagerAdapter.FragmentInfo>();

    for(int i = 0; i < StaticClass.a.Length; i++
         {
          fragments.add(
          new MvxFragmentPagerAdapter.FragmentInfo("RecyclerView " + (i+1).ToString(), typeof (RecyclerViewFragment),typeof (RecyclerViewModel));
         }
    viewPager.Adapter = new MvxFragmentPagerAdapter(Activity, ChildFragmentManager, fragments);

和

'$stateChangeSuccess'

就像我之前所说的，种族调节可能会导致问题，但要测试一下：）

Answer 2

我已经用标签做了类似的事情，有动态数量的标签，这里是代码转储：

<TabHost xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:local="http://schemas.android.com/apk/res-auto"
android:id="@android:id/tabhost"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:keepScreenOn="true">
<LinearLayout
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">
    <include
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        layout="@layout/merge_header" />    
    <TabWidget
        android:id="@android:id/tabs"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />
    <FrameLayout
        android:id="@android:id/tabcontent"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" />
</LinearLayout>

查看：

[Activity(ParentActivity = typeof(HomeView), Theme = "@style/Theme.App", ConfigurationChanges = Android.Content.PM.ConfigChanges.Orientation | Android.Content.PM.ConfigChanges.ScreenSize)]
public class PlanningView : BaseTabActivity<PlanningViewModel>
{
    protected override void OnCreate(Bundle bundle)
    {
        base.OnCreate(bundle);

        SetContentView(Resource.Layout.page_planning);

        ViewModel.BuildInterface();

        CreateTabs();
    }

    void CreateTabs()
    {
        TabHost.TabSpec spec;

        spec = TabHost.NewTabSpec(ViewModel.TextSource.GetText(LocalizationConstants.Planning_Stats));

        spec.SetIndicator(ViewModel.TextSource.GetText(LocalizationConstants.Planning_Stats));

        var intent = new Intent(this.CreateIntentFor(ViewModel.PlanningStats));

        spec.SetContent(intent.AddFlags(ActivityFlags.ClearTop));

        TabHost.AddTab(spec);

        var currentGameweek = ViewModel.CurrentGW;

        foreach (var planningGW in ViewModel.PlanningGW)
        {
            spec = TabHost.NewTabSpec(string.Format("{0}{1}", ViewModel.SharedTextSource.GetText(LocalizationConstants.Shared_GW), planningGW.Gameweek));
            spec.SetIndicator(string.Format("{0}{1}", ViewModel.SharedTextSource.GetText(LocalizationConstants.Shared_GW), planningGW.Gameweek));

            intent = new Intent(this.CreateIntentFor(planningGW));

            spec.SetContent(intent.AddFlags(ActivityFlags.ClearTop));

            TabHost.AddTab(spec);
        }
    }
}

构建界面的viewmodel：

PlanningStatsViewModel _planningStats;
    public PlanningStatsViewModel PlanningStats
    {
        get { return _planningStats; }
        set { _planningStats = value; RaisePropertyChanged(() => PlanningStats); }
    }

    ObservableCollection<PlanningGWViewModel> _planningGW;
    public ObservableCollection<PlanningGWViewModel> PlanningGW
    {
        get { return _planningGW; }
        set { _planningGW = value; RaisePropertyChanged(() => PlanningGW); }
    }

public void BuildInterface()
    {
        PlanningStats = new PlanningStatsViewModel(_dataService, _loadingService, _messenger, _messageService);
        PlanningGW = new ObservableCollection<PlanningGWViewModel>();

        var nonPlayedGameweeks = Service.GetCacheNonPlayedGameweeksAsync().Result;
        var query = nonPlayedGameweeks.ToList();

        if (query.Any())
        {
            CurrentGW = query.Min(f => f.GameWeek);

            var grouped = query.ToList().GroupBy(f => f.GameWeek, f => f, (key, g) => new { Gameweek = key, Fixtures = g.ToList() });

            foreach (var grp in grouped.Take(SettingsPreferences.SelectedPlanUpcoming))
                if (grp.Gameweek <= BusinessConstants.NumGamesSeason)
                    PlanningGW.Add(new PlanningGWViewModel(grp.Gameweek, _dataService, _loadingService, _messenger, _messageService));
        }
    }

每个标签视图模型：

ObservableCollection<PlanningGWItemsViewModelWrapper> _planningGWItems;
    public ObservableCollection<PlanningGWItemsViewModelWrapper> PlanningGWItems
    {
        get { return _planningGWItems; }
        set { _planningGWItems = value; RaisePropertyChanged(() => PlanningGWItems); }
    }

public async Task RebuildLists(bool displayLoading)
    {
        IsLoading = displayLoading;

        Standings = await Service.GetCacheStandingsAsync().ConfigureAwait(false);

        var nonPlayedGameweeks = await Service.GetCacheNonPlayedGameweeksAsync().ConfigureAwait(false);

        PlanningGWItems = await BuildList(Standings, nonPlayedGameweeks.Where(f => f.GameWeek == _gameweek).OrderBy(f => f.Date).ToList()).ConfigureAwait(false);

        IsLoading = false;
    }

创建一些片段以匹配ViewModel中的对象数

2 个答案: