Showing UIView inside a Camera View - ios

Question

I'm making an app that has a camera preview in a View, inside this View I want to draw the camera data and also another View that shows a little rectangle when data it's captured, for example, in a BarCode scanning Scenario the Camera is shown in a view, when a BarCode it's found a Rectangle will be drawn showing that it has scanned a Barcode.
My current View Hierarchy it's the following:
View
{
-UIView cameraHolder
{
-UIView highlightView
}
}
I'm managed to get the camera showed and scanning things, but the highlight View it's not being shown, why is this happening?
This is the code for initializing the highlight View:
-(void)setUpHiglightView{
self.highlightView = [[UIView alloc] init];
self.highlightView.autoresizingMask = UIViewAutoresizingFlexibleTopMargin|UIViewAutoresizingFlexibleLeftMargin|UIViewAutoresizingFlexibleRightMargin|UIViewAutoresizingFlexibleBottomMargin;
self.highlightView.layer.borderColor = [UIColor greenColor].CGColor;
self.highlightView.layer.borderWidth = 3;
}
and this is the code for when a data it's captured:
-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection{
CGRect highlightViewRect = CGRectZero;
AVMetadataMachineReadableCodeObject *barCodeObject;
NSString *detectionString = nil;
NSArray *barCodeTypes = #[AVMetadataObjectTypeUPCECode, AVMetadataObjectTypeCode39Code, AVMetadataObjectTypeCode39Mod43Code,
AVMetadataObjectTypeEAN13Code, AVMetadataObjectTypeEAN8Code, AVMetadataObjectTypeCode93Code, AVMetadataObjectTypeCode128Code,
AVMetadataObjectTypePDF417Code, AVMetadataObjectTypeQRCode, AVMetadataObjectTypeAztecCode];
for(AVMetadataObject *metadata in metadataObjects){
for(NSString *type in barCodeTypes){
if([metadata.type isEqualToString:type]){
barCodeObject = (AVMetadataMachineReadableCodeObject *)[prevLayer transformedMetadataObjectForMetadataObject:(AVMetadataMachineReadableCodeObject*)metadata];
highlightViewRect = barCodeObject.bounds;
detectionString = [(AVMetadataMachineReadableCodeObject*)metadata stringValue];
break;
}
}
}
if(detectionString != nil){
[self.itemIdTextField setText:detectionString];
}else{
//NSLog(#"Got Nothing");
}
NSLog(#"Position: [%f,%f][%f,%f]",highlightViewRect.origin.x, highlightViewRect.origin.y,highlightViewRect.size.height, highlightViewRect.size.width);
self.highlightView.frame = highlightViewRect;
}
Also the code that initializes the camera:
-(void)setupBarCodeScanner{
[self setUpHiglightView];
session = [[AVCaptureSession alloc] init];
device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
NSError *error = nil;
input = [AVCaptureDeviceInput deviceInputWithDevice:device error:&error];
if(input){
[session addInput:input];
}else{
[self showAlertDialogWithTitle:#"Error" andMessage:#"There was an error while accessing your camera"];
NSLog(#"Error: %#", error);
}
output = [[AVCaptureMetadataOutput alloc] init];
[output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
[session addOutput:output];
output.metadataObjectTypes = [output availableMetadataObjectTypes];
prevLayer = [AVCaptureVideoPreviewLayer layerWithSession:session];
prevLayer.frame = self.cameraHolder.bounds;
prevLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
[self.cameraHolder.layer addSublayer:prevLayer];
}
Thank you very much!

Answer 1

Add self.highlightView to self.view at the end of captureOutput:
[self.view addSubview:self.highlightView];

Answer 2

It doesn't look like you're adding that view anywhere. You create it and set its frame, but I'm not seeing where you're adding to the view hierarchy.