Hide controls on Jitsi call screen for PiP mode

Riot/Modules/Integrations/Widgets/Jitsi/JitsiViewController.m

@@ -22,8 +22,12 @@
 @import JitsiMeetSDK;
 
 static const NSString *kJitsiDataErrorKey = @"error";
+/**
+ Class name for RCTSafeAreaView. It's in the React Native SDK, so we cannot import its header.
+ */
+static NSString * _Nonnull kRCTSafeAreaViewClassName = @"RCTSafeAreaView";
 
-@interface JitsiViewController () <JitsiMeetViewDelegate>
+@interface JitsiViewController () <PictureInPicturable, JitsiMeetViewDelegate>
 
 // The jitsi-meet SDK view
 @property (nonatomic, weak) IBOutlet JitsiMeetView *jitsiMeetView;
@@ -33,6 +37,11 @@ static const NSString *kJitsiDataErrorKey = @"error";
 @property (nonatomic, strong) NSString *jwtToken;
 @property (nonatomic) BOOL startWithVideo;
 
+/**
+ Overlay views in self.jitsiMeetView. Only provided if the screen is in the PiP mode.
+ */
+@property (nonatomic, strong) NSArray<UIView*> *overlayViews;
+
 @end
 
 @implementation JitsiViewController
@@ -265,6 +274,26 @@ static const NSString *kJitsiDataErrorKey = @"error";
     }
 }
 
+/**
+ Finds all the views in self.jitsiMeetView recursively those kind of class with the name `kRCTSafeAreaViewClassName`.
+ */
+- (NSArray<UIView*>*)overlayViewsIn:(UIView *)view
+{
+    Class class = NSClassFromString(kRCTSafeAreaViewClassName);
+    if ([view isKindOfClass:class])
+    {
+        return @[view];
+    }
+    
+    NSMutableArray<UIView *> *result = [NSMutableArray arrayWithCapacity:2];
+    
+    [view.subviews enumerateObjectsUsingBlock:^(__kindof UIView * _Nonnull subview, NSUInteger idx, BOOL * _Nonnull stop) {
+        [result addObjectsFromArray:[self overlayViewsIn:subview]];
+    }];
+    
+    return result;
+}
+
 #pragma mark - JitsiMeetViewDelegate
 
 - (void)conferenceWillJoin:(NSDictionary *)data
@@ -309,6 +338,26 @@ static const NSString *kJitsiDataErrorKey = @"error";
     }
 }
 
+#pragma mark - PictureInPicturable
+
+- (void)enterPiP
+{
+    self.overlayViews = [self overlayViewsIn:self.view];
+    for (UIView *view in self.overlayViews)
+    {
+        view.alpha = 0;
+    }
+}
+
+- (void)exitPiP
+{
+    for (UIView *view in self.overlayViews)
+    {
+        view.alpha = 1.0;
+    }
+    self.overlayViews = nil;
+}
+
 @end
 
 #endif