使用闪光灯需要引入AVFoundation框架，使用的类是AVCaptureSession , AVCaptureDevice , AVCaptureDeviceInput，然后在通过设置硬件属性，打开或关闭手电筒或flash就可以实现闪光灯效果，有demo，demo注释很清楚，肯定能让你初步明白怎么打开手电筒，demo链接http://download.csdn.net/download/lcg0412/6832689
一些设置属性：
enum {
AVCaptureDevicePositionB
AVCaptureDevicePositionF
};
typedef NSInteger AVCaptureDevicePosition;
闪光灯开关
enum {
AVCaptureFlashModeOff
AVCaptureFlashModeOn
AVCaptureFlashModeAuto = 2
};
typedef NSInteger AVCaptureFlashMode;
手电筒开关
enum {
AVCaptureTorchModeOff
AVCaptureTorchModeOn
AVCaptureTorchModeAuto = 2,
};
typedef NSInteger AVCaptureTorchMode;
焦距调整
enum {
AVCaptureFocusModeLocked
AVCaptureFocusModeAutoFo
AVCaptureFocusModeContin
};
typedef NSInteger AVCaptureFocusMode;
曝光量调节
enum {
AVCaptureExposureModeLoc
AVCaptureExposureModeAut
AVCaptureExposureModeCon
};
typedef NSInteger AVCaptureExposureMode;
白平衡
enum {
AVCaptureWhiteBalanceMod
AVCaptureWhiteBalanceMod
};
typedef NSInteger AVCaptureWhiteBalanceMod
//提醒
- (void)alertView:(NSString *)text{
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:text message:nil delegate:nil cancelButtonTitle:nil otherButtonTitles:nil];
[alertView show];
[alertView performSelector:@selector(dismissWithClickedButtonIndex:animated:) withObject:@[@0, @YES] afterDelay:1];
}
//定时器，打开或关闭手电筒
- (void)timerAction{
if(self.captureDevice.torchMode == AVCaptureTorchModeOn){
[self openTorch:AVCaptureTorchModeOff];
}
else{
[self openTorch:AVCaptureTorchModeOn];
}
}
//打开或关闭手电筒
- (void)openTorch:(AVCaptureTorchMode)mode{
if(self.captureDevice.torchMode != mode){
//配置会话层
[self.captureSession beginConfiguration];
//对设备进行锁定操作
[self.captureDevice lockForConfiguration:NULL];
//打开手电筒
[self.captureDevice setTorchMode:mode];
//解锁
[self.captureDevice unlockForConfiguration];
//确认配置
[self.captureSession commitConfiguration];
}
}
//闪光灯效果
- (IBAction)flashAction:(UISwitch *)sender {
if(![self.captureDevice hasTorch]){
[self alertView:@"亲，模拟器上没有手电筒哦。"];
return;
}
if(sender.on){
self.torchButton.enabled = NO;
if(self.timer == nil){
self.timer = [NSTimer scheduledTimerWithTimeInterval:.5 target:self selector:@selector(timerAction) userInfo:nil repeats:YES];
}
[self.timer fire];
}
else{
self.torchButton.enabled = YES;
[self.timer invalidate];
self.timer = nil;
}
}
//手电筒效果
- (IBAction)torchOpen:(UISwitch *)sender {
if(![self.captureDevice hasTorch]){
[self alertView:@"亲，模拟器上没有手电筒哦。"];
return;
}
if(sender.on){
self.flashButton.enabled = NO;
[self openTorch:AVCaptureTorchModeOn];
}
else{
self.flashButton.enabled = YES;
[self openTorch:AVCaptureTorchModeOff];
}
}
- (AVCaptureDevice *)captureDevice{
if(_captureDevice == nil){
_captureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
}
return _captureDevice;
}
- (AVCaptureDeviceInput *)captureDeviceInput{
if(_captureDeviceInput == nil){
_captureDeviceInput = [[AVCaptureDeviceInput alloc] initWithDevice:[self captureDevice] error:NULL];
}
return _captureDeviceInput;
}
- (AVCaptureSession *)captureSession{
if(_captureSession == nil){
_captureSession = [[AVCaptureSession alloc] init];
[_captureSession addInput:[self captureDeviceInput]];
}
return _captureSession;
}