Unable binding from class on C#

问题

Here is code of class:

  public class listboxitem
    {
        public string textmenu { get; set; }
        public string logomenu { get; set; }
    }

But when im binding it on textbox that's not show...

I have these array:

 private string[] Logo_menu_array = { "/Assets/star-6-48.ico", "/Assets/note-48.ico", "/Assets/note-48.ico", "medal-48.ico", "joystick-48.ico" };

 private string[] Text_menu_array={"Phổ biến trên YouTuBe","Âm nhạc","Thể thao","Trò chơi"};  

 //load menu
    public void Load_Menu()
    {
        List<listboxitem> text = new List<listboxitem>();
        listboxitem items=new listboxitem();
        for(int i=0;i<Text_menu_array.Length&& i<Logo_menu_array.Length;i++)
        {
            items.textmenu=i.ToString();
        }
        for(int j=0;j<Logo_menu_array.Length;j++)
        {
            items.logomenu = j.ToString();
        }
        text.Add(items);
    }

This website didn't agreed show more code. Ready hard to ask these my question. I added code:

 <ListBox Name="lst_menu" Foreground="Red">
                    <ListBox.ItemTemplate>
                        <DataTemplate>
                            <StackPanel>
                                <Image Source="{Binding logomenu}"></Image>
                                <TextBlock Text="{Binding textmenu}"></TextBlock>
                            </StackPanel>

                        </DataTemplate>
                    </ListBox.ItemTemplate>
                </ListBox>

And here to loaded:

public MainPage()
    {
        this.InitializeComponent();
        //get menu
       List<listboxitem> menu_list = new List<listboxitem>();
       Load_Menu();
       lst_menu.ItemsSource = menu_list;


    }

回答1:

A few things here...

Firstly, we need to see the XAML to see how you are binding this in your UI. I'm going to assume you have something like:

<ListBox ItemSource="{Binding Items}"/>

Then a template that presents these.

In your code you have a List object called text which exists only in your method. You need to assign this value to a property in your view model onto which you can bind - based on the above:

public List<ListItem> Items {get;set;}

This property should trigger PropertyChanged as defined in INotifyPropertyChanged so implement that on your class. Implementing INotifyPropertyChanged

That gets you the basics. If you want to dynamically control this collection - i.e. change items at runtime - you should investigate ObservableCollection.

EDIT: Based upon your full code listing, using code behind. You are setting your lst_menu.ItemsSource to an empty List. Your Load_Menu() builds a collection but does not return it.

public List<listboxitem> Load_Menu()
{
    List<listboxitem> text = new List<listboxitem>();
    listboxitem items=new listboxitem();
    for(int i=0;i<Text_menu_array.Length&& i<Logo_menu_array.Length;i++)
    {
        items.textmenu=i.ToString();
    }
    for(int j=0;j<Logo_menu_array.Length;j++)
    {
        items.logomenu = j.ToString();
    }
    text.Add(items);
    return text;
    // Note you will only ever return one item here - check the logic
}

Then in your constructor:

   List<listboxitem> menu_list = Load_Menu();
   lst_menu.ItemsSource = menu_list;

Assuming you want the arrays to be used to build your collection, try using the following for build menu:

List<listboxitem> text = new List<listboxitem>();
for(int i =0; i< Math.Min(Logo_menu_array.Length, Text_menu_array.Length, i++)
{
    var l = new listboxitem();
    l.logomenu = Logo_menu_array[i];
    l.textmenu = Logo_menu_array[i];
}
return text;

I hope this helps.

来源：https://stackoverflow.com/questions/25133244/unable-binding-from-class-on-c-sharp