Question

我无法使用mvvmcross 4.4.0将可观察集合绑定到axml Android布局文件中。我搜索了很多，但没有任何帮助我。

我的问题是这段代码没有显示任何错误，此外它根本不起作用。

视图模型

public class InitialViewModel : MvxViewModel
{
    MvxObservableCollection<Search> _results;
    public MvxObservableCollection<Search> results
    {
        get { return _results; }
        set
        {
            _results = value;
            RaisePropertyChanged(() => results);
        }
    }
    String _titleToSearch;
    public string titleToSearch
    {
        get { return _titleToSearch; }
        set
        {
            titleToSearch = value;
            RaisePropertyChanged(() => titleToSearch);
        }
    }
    //commands
    public IMvxCommand SearchTitle
    {
        get { return new MvxCommand(async () => await SearchAsync()); }
    }
    public InitialViewModel()
    {
        results = new MvxObservableCollection<Search>();
    }

    //methods
    async Task SearchAsync() { await Task.Run(() => searchByTitle()); }

    void searchByTitle()
    {
        /*
            here i set value to Observablecollection<search>();
            using and api call, its all debbuged and the colletion
            "results" recieve the information.
             public class search{
                 public string a { get; set; }
                 public string b { get; set; }
                 public string c { get; set; }
                 public string d { get; set; }
                 public string e { get; set; }
             }

         */
    }
}

初始axml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:local="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/linearLayout1">
    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content">
        <EditText
            android:id="@+id/editText1"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:textSize="30dp"
            android:lines="1"
            android:layout_weight="1"
            local:MvxBind="Text titleToSearch" />
        <ImageButton
            android:id="@+id/button1"
            android:layout_width="100dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:src="@mipmap/ic_search_white_24dp"
            local:MvxBind="Click SearchTitle" />
    </LinearLayout>
    <ScrollView
        android:id="@+id/scrollView1"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1">
        <Mvx.MvxListView
            android:id="@+id/listView1"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            local:MvxBind="ItemsSource results"
            local:MvxItemTemplate="@layout/listitem" />
    </ScrollView>
</LinearLayout>

listItem axml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:local="http://schemas.android.com/apk/res-auto"
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:padding="20dp">
    <TextView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        local:MvxBind="Text a" />
    <LinearLayout
        android:orientation="vertical"
        android:layout_width="wrap_content"
        android:layout_height="match_parent">
        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:src="@mipmap/ic_note_add_black_24dp" />
        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:src="@mipmap/ic_open_in_new_black_24dp" />
    </LinearLayout>
</LinearLayout>

Answer 1

问题是您LinearLayout中的父Initial.axml未指定方向。到default orientation is horizontal。您需要将其设置为android:orientation="vertical"。

您也无需将MvxListView包裹在ScrollView中。 MvxListView将处理滚动本身。

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:local="http://schemas.android.com/apk/res-auto"
    android:id="@+id/linearLayout1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <EditText
            android:id="@+id/editText1"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:lines="1"
            android:textSize="30dp"
            local:MvxBind="Text titleToSearch" />

        <ImageButton
            android:id="@+id/button1"
            android:layout_width="100dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:src="@drawable/icon"
            local:MvxBind="Click SearchTitle" />
    </LinearLayout>

    <Mvx.MvxListView
        android:id="@+id/listView1"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        local:MvxBind="ItemsSource results"
        local:MvxItemTemplate="@layout/listitem" />

</LinearLayout>

注意：对于您的命令，您可以使用MvxAsyncCommand来简化代码。如果需要，也可以异步执行命令。

public IMvxAsyncCommand SearchTitle
{
    get { return new MvxAsyncCommand(SearchAsync); }
}

Mvvmcross 4.4.0将ViewModel中的可观察集合绑定到axml中的ListView而不使用android中的视图

1 个答案: