iphone - Monotouch.Dialog:启用 ScopeBar 时禁用自动搜索

当我启用 ScopeBar 并在 Monotouch.Dialog 控件上连接 SelectedScopeButtonIndexChanged 时，自动搜索功能会在您启用设置 EnabledSearch=true 已禁用。

以下是它被禁用的方式:

     UISearchBar sb = SearchBar;
     if (sb != null)
     {
        sb.ScopeButtonTitles = new string[] { "Girl".t(),"Boy".t(),"All".t() };
        sb.ShowsScopeBar = true;
        sb.SizeToFit();
        // THIS NEXT LINE KILLS SEARCH, remove to make it all work again
        sb.SelectedScopeButtonIndexChanged+= (sender, e) => {Update();};
     }

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Best Answer-推荐答案

这中断搜索的原因是因为 DialogViewController 在 UISearchBar 上分配了一个自定义 UISearchBarDelegate。

当您连接到一个事件时，它会破坏委托(delegate)并将其替换为一个特殊的 UISearchBarDelegate，它将所有委托(delegate)方法转发给事件。

换句话说，您不能在同一个控件上混合和匹配委托(delegate)与事件。

一种可能的解决方案(如果您不想修补 MonoTouch.Dialog 本身)是用您自己的自定义 UISearchBarDelegate 替换现有的 sb.Delegate ，它可以实现 SearchScope 方法并将其他所有内容转发到已经存在的 UISearchBarDelegate之前设置的。

例如:

public class MySearchBarDelegate : UISearchBarDelegate
{
    UISearchBarDelegate original;
    MyDialogViewController dvc;

    public MySearchBarDelegate (MyDialogViewController dvc, UISearchBarDelegate original)
    {
        this.original = original;
    }

    public override void SelectedScopeButtonIndexChanged (UISearchBar searchBar, int selectedScope)
    {
        dvc.Update ();
    }

    public override void OnEditingStarted (UISearchBar searchBar)
    {
        original.OnEditingStarted (searchBar);
    }

    public override void OnEditingStopped (UISearchBar searchBar)
    {
        original.OnEditingStopped (searchBar);
    }

    public override void TextChanged (UISearchBar searchBar, string searchText)
    {
        original.TextChanged (searchBar, searchText);
    }

    public override void CancelButtonClicked (UISearchBar searchBar)
    {
        original.CancelButtonClicked (searchBar);
    }

    public override void SearchButtonClicked (UISearchBar searchBar)
    {
        original.SearchButtonClicked (searchBar);
    }
}

关于iphone - Monotouch.Dialog:启用 ScopeBar 时禁用自动搜索，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/14551279/