pyobjc_background_assets_download_manager_with_delegate.py

1import BackgroundAssets
2from Foundation import NSObject, NSURL, NSError
3
4class BackgroundDownloadDelegate(NSObject):
5    def download_didFinishWithLocation_(self, download, location):
6        print(f"Download finished: {download.identifier()} at {location.path()}")
7
8    def download_didFailWithError_(self, download, error):
9        print(f"Download failed: {download.identifier()} error: {error.localizedDescription()}")
10
11    def download_didReceiveData_withProgress_(self, download, data, progress):
12        print(f"Progress for {download.identifier()}: {progress * 100}%")
13
14def start_background_download():
15    # 1. Initialize the manager with a delegate
16    delegate = BackgroundDownloadDelegate.alloc().init()
17    manager = BackgroundAssets.BADownloadManager.sharedManager()
18    manager.setDelegate_(delegate)
19
20    # 2. Create a URL for the asset
21    url = NSURL.URLWithString_("https://example.com/large-asset.zip")
22
23    # 3. Create a download object (BAURLDownload)
24    # The identifier must be unique to your application
25    download = BackgroundAssets.BAURLDownload.alloc().initWithIdentifier_request_applicationGroupIdentifier_(
26        "com.example.unique.asset.id",
27        BackgroundAssets.NSURLRequest.requestWithURL_(url),
28        "group.com.example.assets" # Must match your App Group entitlement
29    )
30
31    # 4. Schedule the download
32    error_ptr = None
33    success, error = manager.scheduleDownload_error_(download, error_ptr)
34
35    if success:
36        print("Download scheduled successfully.")
37    else:
38        print(f"Failed to schedule download: {error}")
39
40if __name__ == "__main__":
41    start_background_download()