ResourceContext 类

定义

命名空间:

Windows.ApplicationModel.Resources.Core

封装可能影响资源选择的所有因素 (ResourceQualifier) 。

public ref class ResourceContext sealed

/// [Windows.Foundation.Metadata.ContractVersion(Windows.Foundation.UniversalApiContract, 65536)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
/// [Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
/// [Windows.Foundation.Metadata.Activatable(65536, "Windows.Foundation.UniversalApiContract")]
class ResourceContext final

[Windows.Foundation.Metadata.ContractVersion(typeof(Windows.Foundation.UniversalApiContract), 65536)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
[Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
[Windows.Foundation.Metadata.Activatable(65536, "Windows.Foundation.UniversalApiContract")]
public sealed class ResourceContext

function ResourceContext()

Public NotInheritable Class ResourceContext

继承

Object Platform::Object IInspectable ResourceContext

属性

ActivatableAttribute ContractVersionAttribute MarshalingBehaviorAttribute ThreadingAttribute

Windows 要求

设备系列	Windows 10 (在 10.0.10240.0 中引入)
API contract	Windows.Foundation.UniversalApiContract (在 v1.0 中引入)

示例

此示例基于 应用程序资源和本地化示例的方案 12。 有关完整解决方案，请参阅示例。

private async void Scenario12Button_Show_Click(object sender, RoutedEventArgs e)
{
    // Two coding patterns will be used:
    //   1. Get a ResourceContext on the UI thread using GetForCurrentView and pass 
    //      to the non-UI thread
    //   2. Get a ResourceContext on the non-UI thread using GetForViewIndependentUse
    //
    // Two analogous patterns could be used for ResourceLoader instead of ResourceContext.

    // pattern 1: get a ResourceContext for the UI thread
    ResourceContext defaultContextForUiThread = ResourceContext.GetForCurrentView();

    // pattern 2: we'll create a view-independent context in the non-UI worker thread

    // We need some things in order to display results in the UI (doing that
    // for purposes of this sample, to show that work was actually done in the
    // worker thread):
    List<string> uiDependentResourceList = new List<string>();
    List<string> uiIndependentResourceList = new List<string>();

    // use a worker thread for the heavy lifting so the UI isn't blocked
    await Windows.System.Threading.ThreadPool.RunAsync(
        (source) =>
        {
            ResourceMap stringResourceMap = ResourceManager.Current.MainResourceMap.GetSubtree("Resources");

            // pattern 1: the defaultContextForUiThread variable was created above and is visible here

            // pattern 2: get a view-independent ResourceContext
            ResourceContext defaultViewIndependentResourceContext = ResourceContext.GetForViewIndependentUse();

            // NOTE: The ResourceContext obtained using GetForViewIndependentUse() has no scale qualifier
            // value set. If this ResourceContext is used in its default state to retrieve a resource, that 
            // will work provided that the resource does not have any scale-qualified variants. But if the
            // resource has any scale-qualified variants, then that will fail at runtime.
            //
            // A scale qualifier value on this ResourceContext can be set programmatically. If that is done,
            // then the ResourceContext can be used to retrieve a resource that has scale-qualified variants.
            // But if the scale qualifier is reset (e.g., using the ResourceContext.Reset() method), then
            // it will return to the default state with no scale qualifier value set, and cannot be used
            // to retrieve any resource that has scale-qualified variants.

            // simulate processing a number of items
            // just using a single string resource: that's sufficient to demonstrate 
            for (var i = 0; i < 4; i++)
            {
                // pattern 1: use the ResourceContext from the UI thread
                string listItem1 = stringResourceMap.GetValue("string1", defaultContextForUiThread).ValueAsString;
                uiDependentResourceList.Add(listItem1);

                // pattern 2: use the view-independent ResourceContext
                string listItem2 = stringResourceMap.GetValue("string1", defaultViewIndependentResourceContext).ValueAsString;
                uiIndependentResourceList.Add(listItem2);
            }
        });

    // Display the results in one go. (A more finessed design might add results
    // in the UI asynchronously, but that goes beyond what this sample is 
    // demonstrating.)
    ViewDependentResourcesList.ItemsSource = uiDependentResourceList;
    ViewIndependentResourcesList.ItemsSource = uiIndependentResourceList;
}

void Scenario12::Scenario12Button_Show_Click(Platform::Object^ sender, Windows::UI::Xaml::RoutedEventArgs^ e)
{
    // Two coding patterns will be used:
    //   1. Get a ResourceContext on the UI thread using GetForCurrentView and pass 
    //      to the non-UI thread
    //   2. Get a ResourceContext on the non-UI thread using GetForViewIndependentUse
    //
    // Two analogous patterns could be used for ResourceLoader instead of ResourceContext.

    // pattern 1: get a ResourceContext for the UI thread
    ResourceContext^ defaultContextForUiThread = ResourceContext::GetForCurrentView();

    // pattern 2: we'll create a view-independent context in the non-UI worker thread

    // We need some things in order to display results in the UI (doing that
    // for purposes of this sample, to show that work was actually done in the
    // worker thread): a pair of vectors to capture data, and a pair of variable 
    // references to the controls where the results will be displayed (needed to
    // pass to the .then lambda).
    Platform::Collections::Vector<Platform::String^>^ uiDependentResourceItems = ref new Platform::Collections::Vector<Platform::String^>();
    Platform::Collections::Vector<Platform::String^>^ uiIndependentResourceItems = ref new Platform::Collections::Vector<Platform::String^>();
    ItemsControl^ viewDependentListControl = ViewDependentResourcesList;
    ItemsControl^ viewIndependentListControl = ViewIndependentResourcesList;


    // use a worker thread for the heavy lifting so the UI isn't blocked
    concurrency::create_task(
        Windows::System::Threading::ThreadPool::RunAsync(
            ref new Windows::System::Threading::WorkItemHandler(
            [defaultContextForUiThread, uiDependentResourceItems, uiIndependentResourceItems](Windows::Foundation::IAsyncAction^ /*action*/)
        {
            // This is happening asynchronously on a background worker thread,
            // not on the UI thread.
            ResourceMap^ stringResourceMap = ResourceManager::Current->MainResourceMap->GetSubtree("Resources");

            // coding pattern 1: the defaultContextForUiThread variable was created above and has been captured to use here

            // coding pattern 2: get a view-independent ResourceContext
            ResourceContext^ defaultViewIndependentResourceContext = ResourceContext::GetForViewIndependentUse();

            // NOTE: The ResourceContext obtained using GetForViewIndependentUse() has no scale qualifier
            // value set. If this ResourceContext is used in its default state to retrieve a resource, that 
            // will work provided that the resource does not have any scale-qualified variants. But if the
            // resource has any scale-qualified variants, then that will fail at runtime.
            //
            // A scale qualifier value on this ResourceContext can be set programmatically. If that is done,
            // then the ResourceContext can be used to retrieve a resource that has scale-qualified variants.
            // But if the scale qualifier is reset (e.g., using the ResourceContext::Reset() method), then
            // it will return to the default state with no scale qualifier value set, and cannot be used
            // to retrieve any resource that has scale-qualified variants.

            // simulate processing a number of items
            // just using a single string resource: that's sufficient to demonstrate 
            for (auto i = 0; i < 4; i++)
            {
                // pattern 1: use the ResourceContext from the UI thread
                Platform::String^ item1 = stringResourceMap->GetValue("string1", defaultContextForUiThread)->ValueAsString;
                uiDependentResourceItems->Append(item1);

                // pattern 2: use the view-independent ResourceContext
                Platform::String^ item2 = stringResourceMap->GetValue("string1", defaultViewIndependentResourceContext)->ValueAsString;
                uiIndependentResourceItems->Append(item2);
            }
        }))
    ).then([uiDependentResourceItems, uiIndependentResourceItems, viewDependentListControl, viewIndependentListControl]
    {
        // After the async work is complete, this will execute on the UI thread.

        // Display the results in one go. (A more finessed design might add results
        // in the UI asynchronously, but that goes beyond what this sample is 
        // demonstrating.)
        viewDependentListControl->ItemsSource = uiDependentResourceItems;
        viewIndependentListControl->ItemsSource = uiIndependentResourceItems;
    });
}

注解

资源对缩放可能很敏感，并且应用拥有的不同视图能够在不同的显示设备上同时显示，这些设备可能使用不同的缩放比例。 因此，ResourceContext 通常与特定视图相关联，应使用 GetForCurrentView 获取。 (可以使用 GetForViewIndependentUse 获取独立于视图的 ResourceContext，但请注意，如果在与 view.) 不关联的 ResourceContext 上调用与缩放相关的功能，则依赖于缩放的功能将失败 )

请勿使用 构造函数创建 ResourceContext 实例，因为它已弃用，并会在将来的版本中删除。

除非另有说明，否则可以在任何线程上调用此类的方法。

版本历史记录

Windows 版本	SDK 版本	增值
1903	18362	GetForUIContext

构造函数

ResourceContext()

创建克隆的 ResourceContext 对象。 注意 resourceContext 构造函数可能会在Windows 8.1后更改或不可用。 请改用 GetForCurrentView 和 Clone。

属性

Languages	获取或设置此上下文的语言限定符。
QualifierValues	获取所有受支持限定符的可写、可观测映射，并按名称编制索引。

方法

Clone()	创建具有相同限定符的此 ResourceContext 的克隆。
CreateMatchingContext(IIterable<ResourceQualifier>)	创建与提供的一组限定符匹配的新 ResourceContext 。 注意 CreateMatchingContext 可能会在Windows 8.1后更改或不可用。 请改用 ResourceContext.GetForCurrentView.OverrideToMatch。
GetForCurrentView()	获取与当前正在运行的应用程序的当前视图关联的默认 ResourceContext 。
GetForUIContext(UIContext)	获取与当前正在运行的应用程序的指定 UIContext 关联的默认 ResourceContext。
GetForViewIndependentUse()	获取不与任何视图关联的默认 ResourceContext 。
OverrideToMatch(IIterable<ResourceQualifier>)	重写此上下文提供的限定符值，以匹配已解析的 ResourceQualifier的指定列表。 通常，已解析的 ResourceQualifier与之前查找的资源相关联。
Reset()	重置给定 ResourceContext 实例上所有限定符的重写值。
Reset(IIterable<String>)	重置给定 ResourceContext 实例上指定限定符的重写值。
ResetGlobalQualifierValues()	从整个应用的所有视图的默认上下文中删除任何限定符替代。
ResetGlobalQualifierValues(IIterable<String>)	从整个应用的所有视图的默认上下文中删除指定限定符的限定符替代。
SetGlobalQualifierValue(String, String)	将单个限定符值重写应用于当前应用的所有视图的默认上下文。
SetGlobalQualifierValue(String, String, ResourceQualifierPersistence)	将单个限定符值重写应用于当前应用的所有视图的默认上下文，并指定替代的持久性。

另请参阅

• ResourceQualifier
• 应用程序资源和本地化示例