Port fix from upstream/master from pull request (apache#534) to fix t…

…he window not opening on iOS 13.

src/ios/CDVUIInAppBrowser.m

@@ -259,21 +259,29 @@ - (void)show:(CDVInvokedUrlCommand*)command
     // Run later to avoid the "took a long time" log message.
     dispatch_async(dispatch_get_main_queue(), ^{
         if (weakSelf.inAppBrowserViewController != nil) {
-            if (!tmpWindow) {
-            CGRect frame = [[UIScreen mainScreen] bounds];
-                tmpWindow = [[UIWindow alloc] initWithFrame:frame];
+            float osVersion = [[[UIDevice currentDevice] systemVersion] floatValue];
+            __strong __typeof(weakSelf) strongSelf = weakSelf;
+            if (!strongSelf->tmpWindow) {
+                CGRect frame = [[UIScreen mainScreen] bounds];
+                strongSelf->tmpWindow = [[UIWindow alloc] initWithFrame:frame];
             }
             UIViewController *tmpController = [[UIViewController alloc] init];
-            [tmpWindow setRootViewController:tmpController];
 
-            [tmpWindow makeKeyAndVisible];
+            [strongSelf->tmpWindow setRootViewController:tmpController];
+            [strongSelf->tmpWindow setWindowLevel:UIWindowLevelNormal];
+
+            [self->tmpWindow makeKeyAndVisible];
             [tmpController presentViewController:nav animated:YES completion:nil];
         }
     });
 }
 
 - (void)hide:(CDVInvokedUrlCommand*)command
 {
+    // Set tmpWindow to hidden to make main webview responsive to touch again
+    // https://stackoverflow.com/questions/4544489/how-to-remove-a-uiwindow
+    self->tmpWindow.hidden = YES;
+
     if (self.inAppBrowserViewController == nil) {
         NSLog(@"Tried to hide IAB after it was closed.");
         return;
@@ -465,7 +473,7 @@ - (BOOL)webView:(UIWebView*)theWebView shouldStartLoadWithRequest:(NSURLRequest*
     BOOL useBeforeLoad = NO;
     NSString* httpMethod = request.HTTPMethod;
     NSString* errorMessage = nil;
-    
+
     if([_beforeload isEqualToString:@"post"]){
         //TODO handle POST requests by preserving POST data then remove this condition
         errorMessage = @"beforeload doesn't yet support POST requests";
@@ -527,11 +535,11 @@ - (BOOL)webView:(UIWebView*)theWebView shouldStartLoadWithRequest:(NSURLRequest*
         CDVPluginResult* pluginResult = [CDVPluginResult resultWithStatus:CDVCommandStatus_OK
                                                       messageAsDictionary:@{@"type":@"beforeload", @"url":[url absoluteString]}];
         [pluginResult setKeepCallback:[NSNumber numberWithBool:YES]];
-        
+
         [self.commandDelegate sendPluginResult:pluginResult callbackId:self.callbackId];
         return NO;
     }
-    
+
     if(errorMessage != nil){
         NSLog(errorMessage);
         CDVPluginResult* pluginResult = [CDVPluginResult resultWithStatus:CDVCommandStatus_ERROR
@@ -604,6 +612,9 @@ - (void)browserExit
     // Don't recycle the ViewController since it may be consuming a lot of memory.
     // Also - this is required for the PDF/User-Agent bug work-around.
     self.inAppBrowserViewController = nil;
+    // Set tmpWindow to hidden to make main webview responsive to touch again
+    // Based on https://stackoverflow.com/questions/4544489/how-to-remove-a-uiwindow
+    self->tmpWindow.hidden = YES;
 
     if (IsAtLeastiOSVersion(@"7.0")) {
         if (_previousStatusBarStyle != -1) {