在 Xcode 中为 iPhone 5 手电筒应用调暗 LED
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Dimming the LED for iPhone 5 flashlight app in Xcode
提问by user1792444
I am looking to dim the flashlight's LED with a slider option. I know Apple supports this for iOS 6 however, I am not really sure what code to use. Here is the code I have currently in the .m file.
我想用滑块选项调暗手电筒的 LED。我知道 Apple 支持 iOS 6，但是，我不确定要使用什么代码。这是我目前在 .m 文件中的代码。
-(IBAction)torchOn:(id)sender;
{
onButton.hidden = YES;
offButton.hidden = NO;
onView.hidden = NO;
offView.hidden = YES;
AVCaptureDevice *flashLight = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
if([flashLight isTorchAvailable] && [flashLight isTorchModeSupported:AVCaptureTorchModeOn])
{
BOOL success = [flashLight lockForConfiguration:nil];
if(success)
{
[flashLight setTorchMode:AVCaptureTorchModeOn];
[flashLight unlockForConfiguration];
}
}
}
-(IBAction)torchOff:(id)sender;
{
onButton.hidden = NO;
offButton.hidden = YES;
onView.hidden = YES;
offView.hidden = NO;
AVCaptureDevice *flashLight = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
if([flashLight isTorchAvailable] && [flashLight isTorchModeSupported:AVCaptureTorchModeOn])
{
BOOL success = [flashLight lockForConfiguration:nil];
if(success)
{
[flashLight setTorchMode:AVCaptureTorchModeOff];
[flashLight unlockForConfiguration];
}
}
}
回答by Daniel Amitay
- (BOOL)setTorchModeOnWithLevel:(float)torchLevel error:(NSError **)outError
- (BOOL)setTorchModeOnWithLevel:(float)torchLevel error:(NSError **)outError
Does what you want. However, from what I can see, it only updates in certain intervals (~0.2).
做你想做的。但是，据我所知，它仅以特定时间间隔（~0.2）更新。
AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
[device lockForConfiguration:nil];
[device setTorchModeOnWithLevel:slider.value error:NULL];
[device unlockForConfiguration];
Edit - Full Example:
编辑 - 完整示例：
Here is a UISlider. You need to add an IBAction outlet to your slider or programmatically add a target (like I do):
这是一个 UISlider。您需要向滑块添加一个 IBAction 插座或以编程方式添加一个目标（就像我一样）：
UISlider *slider = [[UISlider alloc] initWithFrame:CGRectMake(20.0f, 20.0f, 280.0f, 40.0f)];
slider.maximumValue = 1.0f;
slider.minimumValue = 0.0f;
[slider setContinuous:YES];
[slider addTarget:self action:@selector(sliderDidChange:) forControlEvents:UIControlEventValueChanged];
[self.view addSubview:slider];
Then, in response to the slider changing:
然后，响应滑块的变化：
- (void)sliderDidChange:(UISlider *)slider
{
AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
[device lockForConfiguration:nil];
[device setTorchModeOnWithLevel:slider.value error:NULL];
[device unlockForConfiguration];
}
回答by user2350321
If there are two sliders it's because the slider is set in the m. file you have to delete the [self.view addSubview:slider];part of the code.
如果有两个滑块，那是因为滑块设置在 m 中。文件你必须删除[self.view addSubview:slider];代码的一部分。
