Camera Flash is not working

Question

I am trying to make an extension for marmalade, which turns on and off the camera flash in iPhone. I am referring to this answer on SO about using camera flash. I've put the exact code what he has mentioned and [device setTorchMode:AVCaptureTorchModeOn]; gets called too. But the flash doesn't respond, as if nothing has happened. Is there anything I need to do, to make it work as a static library, so that I can use it in my extension?

Update:-
I am using iOS-SDK 6.1 to compile the extension and was testing on iPhone 4 (iOS version 4.3.1). But now I am testing on iPhone 5 (iOS version 6.0.0), and now the flash is turning on, but not turning off. I guess this might help.

score 3 · Answer 1 · answered May 15 '13 at 05:37

3

That code you copied may have an error in it. Try the following:

-(void)turnOnFlash
{
    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
        if ([device hasTorch]) {
            [device lockForConfiguration:nil];
            [device setTorchMode:AVCaptureTorchModeOff];
            [device unlockForConfiguration];
        }
}

answered May 15 '13 at 05:37

dana0550

1,125
1
9
16

It looks like the same code to me. Let me try this to see if that works. Thanks – 0xC0DED00D May 15 '13 at 05:38

score 3 · Accepted Answer · answered May 16 '13 at 12:27

I don't know why, but the below code worked for me.

void TurnFlashOn_platform(bool turnOn) { 
    AVCaptureDevice* device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    if ([device hasTorch]){
        [device lockForConfiguration:nil]; //you must lock before setting torch mode
        [device setTorchMode:turnOn ? AVCaptureTorchModeOn : AVCaptureTorchModeOff];
        [device unlockForConfiguration];
    }
}

I guess must be some typos. Thanks anyways.

score 2 · Answer 3 · answered May 15 '13 at 05:52

2

Use this function to turn on and off the flash light...

#import <AVFoundation/AVFoundation.h>


- (void) turnTorchOn: (bool) on {

Class captureDeviceClass = NSClassFromString(@"AVCaptureDevice");
if (captureDeviceClass != nil) {
    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    if ([device hasTorch] && [device hasFlash]){

        [device lockForConfiguration:nil];
        if (on) {
            [device setTorchMode:AVCaptureTorchModeOn];
            [device setFlashMode:AVCaptureFlashModeOn];
            torchIsOn = YES;
        } else {
            [device setTorchMode:AVCaptureTorchModeOff];
            [device setFlashMode:AVCaptureFlashModeOff];
            torchIsOn = NO;            
        }
        [device unlockForConfiguration];
    }
}
}

answered May 15 '13 at 05:52

Divyu

1,325
9
21

Now that's exactly the same answer I was referring too. Can You point out what problem it may have, while using this method statically? – 0xC0DED00D May 15 '13 at 06:14
I don't understand what is the actual problem you are facing while using this code.. can u tell me? – Divyu May 15 '13 at 07:17
It's not working. No flash blink, despite all methods running perfectly. – 0xC0DED00D May 15 '13 at 07:27

Camera Flash is not working

3 Answers3