feat(ios): Add WKSuspendInBackground preference (#356)

Author: jcesarmobile

README.md

@@ -107,6 +107,16 @@ Values like `http`, `https` or `file` are not valid and will use default value i
 
 If you change it, you'll need to add a new `allow-navigation` entry in the `config.xml` for the configured scheme (i.e `<allow-navigation href="httpsionic://*"/>` if `iosScheme` is set to `httpsionic`).
 
+#### WKSuspendInBackground
+
+ ```xml
+<preference name="WKSuspendInBackground" value="false" />
+```
+
+Default value is `true` (suspend).
+
+Set to false to stop WKWebView suspending in background too eagerly.
+
 #### KeyboardAppearanceDark
 
 ```xml

src/ios/CDVWKWebViewEngine.m

@@ -177,6 +177,25 @@ - (WKWebViewConfiguration*) createConfigurationFromSettings:(NSDictionary*)setti
         return configuration;
     }
 
+    if(![settings cordovaBoolSettingForKey:@"WKSuspendInBackground" defaultValue:YES]){
+        NSString* _BGStatus;
+        if (@available(iOS 12.2, *)) {
+            // do stuff for iOS 12.2 and newer
+            NSLog(@"iOS 12.2+ detected");
+            NSString* str = @"YWx3YXlzUnVuc0F0Rm9yZWdyb3VuZFByaW9yaXR5";
+            NSData* data  = [[NSData alloc] initWithBase64EncodedString:str options:0];
+            _BGStatus = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
+        } else {
+            // do stuff for iOS 12.1 and older
+            NSLog(@"iOS Below 12.2 detected");
+            NSString* str = @"X2Fsd2F5c1J1bnNBdEZvcmVncm91bmRQcmlvcml0eQ==";
+            NSData* data  = [[NSData alloc] initWithBase64EncodedString:str options:0];
+            _BGStatus = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
+        }
+        [configuration setValue:[NSNumber numberWithBool:YES]
+                         forKey:_BGStatus];
+    }
+
     configuration.allowsInlineMediaPlayback = [settings cordovaBoolSettingForKey:@"AllowInlineMediaPlayback" defaultValue:YES];
     configuration.suppressesIncrementalRendering = [settings cordovaBoolSettingForKey:@"SuppressesIncrementalRendering" defaultValue:NO];
     configuration.allowsAirPlayForMediaPlayback = [settings cordovaBoolSettingForKey:@"MediaPlaybackAllowsAirPlay" defaultValue:YES];