C# xamarin表单选取器集选定项

对于我的Xamarin表单应用程序，我使用选择器选择测验类别的子类别

<Picker x:Name="subCategory" Title="SUBCategory" ItemsSource="{Binding SubCategories}" ItemDisplayBinding="{Binding Subcategory}" SelectedItem="{Binding selSubCategories, Mode=TwoWay}" />

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有人知道如何将选择器的默认文本设置为源中的一个项吗？

您需要为SelectedItem字段实现OnPropertyChanged，如：

private SubCategory _selSubCategories;
public SubCategory selSubCategories
{
    get { return _selSubCategories; }
    set
    {
        _selSubCategories = value;
        OnPropertyChanged(nameof(selSubCategories));
    }
}

---

您需要为SelectedItem字段实现OnPropertyChanged，如：

private SubCategory _selSubCategories;
public SubCategory selSubCategories
{
    get { return _selSubCategories; }
    set
    {
        _selSubCategories = value;
        OnPropertyChanged(nameof(selSubCategories));
    }
}

---

Thx，这对我帮助很大！Thx，这对我帮助很大！

private SubCategory _selSubCategories;
public SubCategory selSubCategories
{
    get { return _selSubCategories; }
    set
    {
        _selSubCategories = value;
        OnPropertyChanged(nameof(selSubCategories));
    }
}