public DataExampleViewModel()
{
StartLongRunningDataLoader = new DataLoader();
StartLongRunningWithExceptionDataLoader = new DataLoader(); //swallow exceptions by default
CacheDataLoader = new DataLoader();
CacheWithExceptionDataLoader = new DataLoader(); //swallow exceptions by default
SourceABDataLoader = new DataLoader(); //swallow exceptions by default
CacheRefreshDataLoader = new DataLoader(); //swallow exceptions by default
FailCacheDataLoader = new DataLoader();
FailCacheSuccessDataLoader = new DataLoader();
StartLongRunningCommand = new RelayCommand(() => StartLongRunningAction());
StartLongRunningWithExceptionCommand = new RelayCommand(() => StartLongRunningWithExceptionAction());
CacheCommand = new RelayCommand(() => CacheAction());
CacheWithExceptionCommand = new RelayCommand(() => CacheWithExceptionAction());
SourceABCommand = new RelayCommand(() => SourceABAction());
CacheRefreshCommand = new RelayCommand(() => CacheRefreshAction());
ClearCacheCommand = new RelayCommand(() => ClearCacheAction());
FailCacheCommand = new RelayCommand(() => FailCacheAction());
FailCacheSuccessCommand = new RelayCommand(() => FailCacheSuccessAction());
ClearWebDataCacheCommand = new RelayCommand(() => ClearWebDataCacheCommandAction());
GetUriCommand = new RelayCommand(() => GetUriCommandAction());
ImageBrushUri = new Uri("https://pbs.twimg.com/profile_images/478304416148099072/1_rxoQgR.png");
WebDataCache.Init();
}
private static async void OnCacheUriChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
//Uri oldCacheUri = (Uri)e.OldValue;
Uri newCacheUri = (Uri)d.GetValue(CacheUriProperty);
var image = (Image)d;
if (newCacheUri != null)
{
try
{
//Get image from cache (download and set in cache if needed)
var cacheUri = await WebDataCache.GetLocalUriAsync(newCacheUri);
//Set cache uri as source for the image
image.Source = new BitmapImage(cacheUri);
}
catch (Exception ex)
{
Debug.WriteLine(ex);
//Revert to using passed URI
image.Source = new BitmapImage(newCacheUri);
}
}
else
{
image.Source = null;
}
}
public async Task <string> GetLocalImagePath(Uri webUri)
{
//Download and save image
var localUri = await WebDataCache.GetLocalUriAsync(webUri);
return(localUri.AbsolutePath);
}
private async static void ActualImageSourceChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
{
DelayLoadImage instance = o as DelayLoadImage;
if (instance == null)
{
return;
}
instance.imageLoaded = false;
var newCacheUri = e.NewValue;
if (newCacheUri == null)
{
return;
}
var cacheUri =
await WebDataCache.GetLocalUriAsync(new Uri(newCacheUri.ToString(), UriKind.RelativeOrAbsolute));
instance._image.UriSource = cacheUri;
VisualStateManager.GoToState(instance, STATE_DEFAULT_NAME, false);
//这里引入Q42的缓存
}
// Code to execute when the application is activated (brought to foreground)
// This code will not execute when the application is first launched
private async void Application_Activated(object sender, ActivatedEventArgs e)
{
if (!e.IsApplicationInstancePreserved)
{
await WebDataCache.Init();
}
}
/// <summary>
/// Load uri and set data in cache
/// </summary>
private async void GetUriCommandAction()
{
var result = await WebDataCache.GetAsync(new Uri("http://microsoft.com"), forceGet : false);
if (result == null)
{
}
}
public async Task GetAsyncLongUriTest()
{
int length = 500;
var baseUri = "http://www.google.com/favicon.ico?";
var q = new string('x', length - baseUri.Length);
await WebDataCache.GetAsync(new Uri(baseUri + q), true);
}
private static async void OnCacheUriChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
//Uri oldCacheUri = (Uri)e.OldValue;
Uri newCacheUri = (Uri)d.GetValue(CacheUriProperty);
if (newCacheUri != null)
{
try
{
//Get image from cache (download and set in cache if needed)
var cacheUri = await WebDataCache.GetLocalUriAsync(newCacheUri);
// Check if the wanted image uri has not changed while we were loading
if (newCacheUri != (Uri)d.GetValue(CacheUriProperty))
{
return;
}
#if NETFX_CORE
//Set cache uri as source for the image
SetSourceOnObject(d, new BitmapImage(cacheUri));
#elif WINDOWS_PHONE
BitmapImage bimg = new BitmapImage();
using (IsolatedStorageFile iso = IsolatedStorageFile.GetUserStoreForApplication())
{
using (IsolatedStorageFileStream stream = iso.OpenFile(cacheUri.PathAndQuery, FileMode.Open, FileAccess.Read))
{
bimg.SetSource(stream);
}
}
//Set cache uri as source for the image
SetSourceOnObject(d, bimg);
#endif
}
catch (Exception ex)
{
Debug.WriteLine(ex);
//Revert to using passed URI
SetSourceOnObject(d, new BitmapImage(newCacheUri), false);
}
}
else
{
SetSourceOnObject(d, null, false);
}
}
public async Task <Uri> GetLocalImageUri(Uri webUri)
{
//First delete all old images
try
{
await WebDataCache.ClearAll();
}
catch (Exception e)
{
}
//Download and save image
var localUri = await WebDataCache.GetLocalUriAsync(webUri);
return(localUri);
}
public object Convert(object value, Type targetType, object parameter, string language)
{
var path = value as string;
if (String.IsNullOrEmpty(path))
{
return(null);
}
var imageFileUri = new Uri(path);
if (imageFileUri.Scheme == "http" || imageFileUri.Scheme == "https")
{
return(WebDataCache.GetLocalUriAsync(imageFileUri).Result);
}
// 不是网络图片,应用内的素材
var bm = new BitmapImage(imageFileUri);
return(bm);
}
/// <summary>
/// Invoked when the application is launched normally by the end user. Other entry points
/// will be used when the application is launched to open a specific file, to display
/// search results, and so forth.
/// </summary>
/// <param name="args">Details about the launch request and process.</param>
protected override async void OnLaunched(LaunchActivatedEventArgs args)
{
await WebDataCache.Init();
// Do not repeat app initialization when already running, just ensure that
// the window is active
if (args.PreviousExecutionState == ApplicationExecutionState.Running)
{
Window.Current.Activate();
return;
}
// Create a Frame to act as the navigation context and associate it with
// a SuspensionManager key
var rootFrame = new Frame();
SuspensionManager.RegisterFrame(rootFrame, "AppFrame");
if (args.PreviousExecutionState == ApplicationExecutionState.Terminated)
{
// Restore the saved session state only when appropriate
await SuspensionManager.RestoreAsync();
}
if (rootFrame.Content == null)
{
// When the navigation stack isn't restored navigate to the first page,
// configuring the new page by passing required information as a navigation
// parameter
if (!rootFrame.Navigate(typeof(MainPage)))
{
throw new Exception("Failed to create initial page");
}
}
// Place the frame in the current Window and ensure that it is active
Window.Current.Content = rootFrame;
Window.Current.Activate();
}
public IllustrationViewModel(Uri imgSourceUri)
{
Content = null;
IsLoading = true;
NonCachedImageUri = imgSourceUri;
var cacheingFileTask = WebDataCache.GetAsync(imgSourceUri);
cacheingFileTask.ContinueWith(localUri =>
{
Deployment.Current.Dispatcher.BeginInvoke(() =>
{
if (localUri.Status != TaskStatus.RanToCompletion)
{
Content = imgSourceUri.AbsolutePath;
}
else
{
Content = localUri.Result.Path;
}
IsLoading = false;
});
});
}
public async Task Init()
{
await WebDataCache.Init();
}
// Code to execute when the application is launching (eg, from Start)
// This code will not execute when the application is reactivated
private async void Application_Launching(object sender, LaunchingEventArgs e)
{
await WebDataCache.Init();
}
public static async void InitNavigationConfigurationInThisAssembly()
{
StartupFunctions.RunAllConfig();
await WebDataCache.Init();
}
private void DeleteButton_Click(object sender, RoutedEventArgs e)
{
WebDataCache.Delete(new Uri("https://www.google.com/images/logo.png"));
}
/// <summary>
/// Clear WebDataCache
/// </summary>
private void ClearWebDataCacheCommandAction()
{
WebDataCache.ClearAll();
}
public async Task GetAsyncTest()
{
await WebDataCache.GetAsync(new Uri("http://www.google.com/favicon.ico"), true);
}
