WKWebView takeSnapshot does not work on iOS 13

Question

jnis OP

Created Jan ’20

Replies 1

Boosts 0

Views 2.2k

Participants 2

I need take screenshot of WebView while app in Background.

But on iOS13 method "takeSnapshotWithConfiguration:completionHandler:" of WKWebView does not work. completionHandler never fire when app does background task.

This works well on iOS12. Also it works on iOS13 while app in foreground.

Reproduce: see demo project to reproduce https://github.com/Jnis/WebView-Snapshot. Also see videos there.

Expected: takeSnapshotWithConfiguration:completionHandler call completionHandler with image while app is in background

Actual result:

[self.wkwebView takeSnapshotWithConfiguration:configuration completionHandler:^(UIImage * _Nullable snapshotImage, NSError * _Nullable error) {

// this never call on iOS13 while app in background. But iOS12 works well.

}];

Thank you!

Boost

Answer 1

jnis OP

Mar ’20

Solution: setting WKSnapshotConfiguration’s afterScreenUpdates property to NO

WKSnapshotConfiguration *configuration = [WKSnapshotConfiguration new];
if (@available(iOS 13.0, *)) {
    configuration.afterScreenUpdates = NO;
}

2