UWP，是否可以以编程方式添加 ResourceDictionary 值？

问题描述

我正在为我的应用添加复杂的主题。我的想法是当用户更改主题时，我加载一个 ResourceDictionary 并在运行时更改它的子项。 但是插入操作总是失败，请帮帮我。

以下是我所做的：

auto newResourceDic = ref new ResourceDictionary();
newResourceDic->Source = ref new Uri("ms-appx:///XAMLPages/test.xaml");
if (newResourceDic->HasKey(L"TitleBarColor"))
{
    newResourceDic->Remove(L"TitleBarColor");  
    //It's a SolidColorBrush,I want to replace this brush to a more complex bitmapbrush
    //For convenience,I use a solidcolorbrush instead
    Windows::UI::Color c;
    c.A = 255;
    c.R = 255;
    c.G = 0;
    c.B = 0;
    testbrush = ref new Windows::UI::Xaml::Media::SolidColorBrush(c);

    //HRESULT:0x800F1000 No installed components were detected.
    //WinRT information: Local values are not allowed in resource dictionary with Source set [Line: 0 Position: 0]
    newResourceDic->Insert("TitleBarColor",testbrush);
}

解决方法

UWP，是否可以通过编程方式添加 ResourceDictionary 值？

当你更新 newResourceDic 时，它会抛出 Local values are not allowed in resource dictionary with Source set 异常，默认情况下，如果你想以编程方式添加 ResourceDictionary 值。我们建议您将 newResourceDic 添加到应用程序 ResourceDictionary.MergedDictionaries 中。然后使用 App.Current.Resources 更新，如下所示

Xaml

<Application.Resources>
    <ResourceDictionary>
        <ResourceDictionary.MergedDictionaries>
            <ResourceDictionary Source="ms-appx:///TestResouce.xaml"/>
        </ResourceDictionary.MergedDictionaries>
    </ResourceDictionary>
</Application.Resources>

C# 代码

if (App.Current.Resources.ContainsKey("TitleBarColor"))
{
    App.Current.Resources["TitleBarColor"] = new SolidColorBrush(Colors.Red);
    App.Current.Resources.Add("HighTitleBarColor",new SolidColorBrush(Colors.Bisque));

}

C++

if (App::Current->Resources->HasKey(L"TitleBarColor")) {
    App::Current->Resources->Remove(L"TitleBarColor");
    Windows::UI::Color c;
    c.A = 255;
    c.R = 255;
    c.G = 0;
    c.B = 0;
    auto testbrush = ref new Windows::UI::Xaml::Media::SolidColorBrush(c);     
    App::Current->Resources->Insert("TitleBarColor",testbrush);
}