访问另一个页面中的图像控件,class windows phone

Access a image control in another page, class windows phone

可以从 C#XAML 中的另一个 class 访问 control (image) 吗? 例如:In class A (image) is collapsed/hidden, check if image is collapsed/hidden in class B, i want to be visible/enabled, 有可能? 谢谢!

您可以使用 PhoneApplicationService 来完成。

例如:
假设您从 class A 导航到 class B
class B 中,在导航回 class A 之前,设置

PhoneApplicationService.Current.State["showImage"] = true;

class A中,实现OnNavigatedTo来处理它:

protected override void OnNavigatedTo(NavigationEventArgs e)
{
    if (PhoneApplicationService.Current.State.ContainsKey("showImage"))
    {
        bool showImage = (bool)PhoneApplicationService.Current.State["showImage"];
        if (showImage)
        {
            this.YourImage.Visibility = System.Windows.Visibility.Visible;
        }
        else
        {
            this.YourImage.Visibility = System.Windows.Visibility.Collapsed;
        }

        PhoneApplicationService.Current.State.Remove("showImage");
    }
}

编辑:

对于多张图片,可以尝试以下方法:

class B 中,不是将 bool 传递给 PhoneApplicationService,而是传递 Dictionary 个布尔值,每个布尔值代表图像的状态:

var showImage = new Dictionary<int, bool>();
showImage[1] = true;
showImage[2] = false;
showImage[3] = true;
PhoneApplicationService.Current.State["showImage"] = showImage;

class A 中,为您的图像创建字典:

private Dictionary<int, Image> _images = new Dictionary<int, Image>();

然后在其构造函数中,用您的图像填充字典:

InitializeComponent();

_images[1] = YourImage1;
_images[2] = YourImage2;
_images[3] = YourImage3;

class AOnNavigatedTo 中,执​​行:

protected override void OnNavigatedTo(NavigationEventArgs e)
{
    if (PhoneApplicationService.Current.State.ContainsKey("showImage"))
    {
        var showImage = PhoneApplicationService.Current.State["showImage"] as Dictionary<int, bool>;
        if (showImage != null)
        {
            foreach (var key in showImage.Keys)
            {
                if (_images.ContainsKey(key))
                {
                    if (showImage[key])
                    {
                        _images[key].Visibility = System.Windows.Visibility.Visible;
                    }
                    else
                    {
                        _images[key].Visibility = System.Windows.Visibility.Collapsed;
                    }
                }
            }
        }
    }
}

如果您愿意,可以更改字典的 key 以获得更具代表性的字符串。

希望对您有所帮助! :)