如何使用 MVVM 在 WP7 中聚焦文本框？

Question

这个问题已经被问过几次了，不幸的是，答案只适用于 WPF。任何人都知道如何在silverlight中实现这一点？基本上我需要关注代码中的某个文本框。

Answer 1

我已经成功地使用了这种方法

http://caliburnmicro.codeplex.com/discussions/222892?ProjectName=caliburnmicro

public class FocusBehavior : Behavior<Control>
    {

        protected override void OnAttached()
        {
            AssociatedObject.GotFocus += (sender, args) => IsFocused = true;
            AssociatedObject.LostFocus += (sender, a) => IsFocused = false;
            AssociatedObject.Loaded += (o, a) => { if (HasInitialFocus || IsFocused) AssociatedObject.Focus(); };

            base.OnAttached();
        }

        public static readonly DependencyProperty IsFocusedProperty =
            DependencyProperty.Register(
                "IsFocused",
                typeof(bool),
                typeof(FocusBehavior),
                new PropertyMetadata(false, (d, e) => { if ((bool)e.NewValue) ((FocusBehavior)d).AssociatedObject.Focus(); }));

        public bool IsFocused
        {
            get { return (bool)GetValue(IsFocusedProperty); }
            set { SetValue(IsFocusedProperty, value); }
        }

        public static readonly DependencyProperty HasInitialFocusProperty =
            DependencyProperty.Register(
                "HasInitialFocus",
                typeof(bool),
                typeof(FocusBehavior),
                new PropertyMetadata(false, null));

        public bool HasInitialFocus
        {
            get { return (bool)GetValue(HasInitialFocusProperty); }
            set { SetValue(HasInitialFocusProperty, value); }
        }
    }

<TextBox x:Name="UserName" Style="{StaticResource LoginTextBox}">
  <i:Interaction.Behaviors>
    <localBehaviors:FocusBehavior HasInitialFocus="True" 
      IsFocused="{Binding UserNameIsFocused, Mode=TwoWay}"/>
  </i:Interaction.Behaviors>
</TextBox>