Specific Delegate Methods

Project/Vision/PBJViewController.m

@@ -465,12 +465,34 @@ - (void)visionSessionDidStop:(PBJVision *)vision
     [_previewView removeFromSuperview];
 }
 
-- (void)visionModeWillChange:(PBJVision *)vision
+- (void)visionCameraModeWillChange:(PBJVision *)vision
 {
+    NSLog(@"Camera mode will change");
 }
 
-- (void)visionModeDidChange:(PBJVision *)vision
+- (void)visionCameraModeDidChange:(PBJVision *)vision
 {
+    NSLog(@"Camera mode did change");
+}
+
+- (void)visionCameraDeviceWillChange:(PBJVision *)vision
+{
+    NSLog(@"Camera device will change");
+}
+
+- (void)visionCameraDeviceDidChange:(PBJVision *)vision
+{
+    NSLog(@"Camera device did change");
+}
+
+- (void)visionOutputFormatWillChange:(PBJVision *)vision
+{
+    NSLog(@"Output format will change");
+}
+
+- (void)visionOutputFormatDidChange:(PBJVision *)vision
+{
+    NSLog(@"Output format did change");
 }
 
 - (void)vision:(PBJVision *)vision didChangeCleanAperture:(CGRect)cleanAperture

Source/PBJVision.h

@@ -147,8 +147,14 @@ extern NSString * const PBJVisionVideoThumbnailKey;
 - (void)visionSessionDidStart:(PBJVision *)vision;
 - (void)visionSessionDidStop:(PBJVision *)vision;
 
-- (void)visionModeWillChange:(PBJVision *)vision;
-- (void)visionModeDidChange:(PBJVision *)vision;
+- (void)visionCameraDeviceWillChange:(PBJVision*)vision;
+- (void)visionCameraDeviceDidChange:(PBJVision*)vision;
+
+- (void)visionCameraModeWillChange:(PBJVision*)vision;
+- (void)visionCameraModeDidChange:(PBJVision*)vision;
+
+- (void)visionOutputFormatWillChange:(PBJVision*)vision;
+- (void)visionOutputFormatDidChange:(PBJVision*)vision;
 
 - (void)vision:(PBJVision *)vision didChangeCleanAperture:(CGRect)cleanAperture;
 

Source/PBJVision.m

@@ -280,8 +280,31 @@ - (void)_setCameraMode:(PBJCameraMode)cameraMode cameraDevice:(PBJCameraDevice)c
     if (!changeMode && !changeDevice && !changeOutputFormat)
         return;
 
-    if ([_delegate respondsToSelector:@selector(visionModeWillChange:)])
-        [_delegate visionModeWillChange:self];
+    SEL targetDelegateMethodBeforeChange;
+    SEL targetDelegateMethodAfterChange;
+
+    if (changeDevice) {
+        targetDelegateMethodBeforeChange = @selector(visionCameraDeviceWillChange:);
+        targetDelegateMethodAfterChange = @selector(visionCameraDeviceDidChange:);
+    }
+    else if (changeMode) {
+        targetDelegateMethodBeforeChange = @selector(visionCameraModeWillChange:);
+        targetDelegateMethodAfterChange = @selector(visionCameraModeDidChange:);
+    }
+    else {
+        targetDelegateMethodBeforeChange = @selector(visionOutputFormatWillChange:);
+        targetDelegateMethodAfterChange = @selector(visionOutputFormatDidChange:);
+    }
+
+    if ([_delegate respondsToSelector:targetDelegateMethodBeforeChange]) {
+        // At this point, `targetDelegateMethodBeforeChange` will always refer to a valid selector, as
+        // from the sequence of conditionals above. Also the enclosing `if` statement ensures
+        // that the delegate responds to it, thus safely ignore this compiler warning.
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
+        [_delegate performSelector:targetDelegateMethodBeforeChange withObject:self];
+#pragma clang diagnostic pop
+    }
 
     _flags.changingModes = YES;
 
@@ -294,8 +317,15 @@ - (void)_setCameraMode:(PBJCameraMode)cameraMode cameraDevice:(PBJCameraDevice)c
     if (!_captureSession) {
         _flags.changingModes = NO;
 
-        if ([_delegate respondsToSelector:@selector(visionModeDidChange:)])
-            [_delegate visionModeDidChange:self];
+        if ([_delegate respondsToSelector:targetDelegateMethodAfterChange]) {
+            // At this point, `targetDelegateMethodAfterChange` will always refer to a valid selector, as
+            // from the sequence of conditionals above. Also the enclosing `if` statement ensures
+            // that the delegate responds to it, thus safely ignore this compiler warning.
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
+            [_delegate performSelector:targetDelegateMethodAfterChange withObject:self];
+#pragma clang diagnostic pop
+        }
 
         return;
     }
@@ -305,8 +335,15 @@ - (void)_setCameraMode:(PBJCameraMode)cameraMode cameraDevice:(PBJCameraDevice)c
         [self _enqueueBlockOnMainQueue:^{
             _flags.changingModes = NO;
 
-            if ([_delegate respondsToSelector:@selector(visionModeDidChange:)])
-                [_delegate visionModeDidChange:self];
+            if ([_delegate respondsToSelector:targetDelegateMethodAfterChange]) {
+                // At this point, `targetDelegateMethodAfterChange` will always refer to a valid selector, as
+                // from the sequence of conditionals above. Also the enclosing `if` statement ensures
+                // that the delegate responds to it, thus safely ignore this compiler warning.
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
+                [_delegate performSelector:targetDelegateMethodAfterChange withObject:self];
+#pragma clang diagnostic pop
+            }
         }];
     }];
 }