typedef enum to Swift enum.如何使用案例来标记暂停和恢复检测空闲计时器已禁用

Question

从

Obj-C typedef 枚举中制定了一个 Swift 枚举声明，但现在我不知道如何在 Swift 中实现它。我看到了一个功能，但我不知道我会用什么来设置空闲/唤醒这两种情况？如何标记暂停和恢复检测空闲计时器已禁用？

//  ViewController.m   
#import "ViewController.h"
#import <AVFoundation/AVFoundation.h>  // import AVFoundation
#import "PulseDetector.h"
#import "Filter.h"
typedef NS_ENUM(NSUInteger, CURRENT_STATE) {
STATE_PAUSED,
STATE_SAMPLING
};
#define MIN_FRAMES_FOR_FILTER_TO_SETTLE 10
@interface ViewController ()<AVCaptureVideoDataOutputSampleBufferDelegate>

// other code here

 // !!!!!!! we're now sampling from the camera. My problem !!!!!!!!
self.currentState=STATE_SAMPLING;

// stop the app from sleeping
[UIApplication sharedApplication].idleTimerDisabled = YES;
// update our UI on a timer every 0.1 seconds
[NSTimer scheduledTimerWithTimeInterval:0.1 target:self selector:@selector(update) userInfo:nil repeats:YES];
}
-(void) stopCameraCapture {
[self.session stopRunning];
self.session=nil;
}
#pragma mark Pause and Resume of detection
-(void) pause {
if(self.currentState==STATE_PAUSED) return;
// switch off the torch
if([self.camera isTorchModeSupported:AVCaptureTorchModeOn]) {
    [self.camera lockForConfiguration:nil];
    self.camera.torchMode=AVCaptureTorchModeOff;
    [self.camera unlockForConfiguration];
}
self.currentState=STATE_PAUSED;
// let the application go to sleep if the phone is idle
[UIApplication sharedApplication].idleTimerDisabled = NO;
}
-(void) resume {
if(self.currentState!=STATE_PAUSED) return;
// switch on the torch
if([self.camera isTorchModeSupported:AVCaptureTorchModeOn]) {
    [self.camera lockForConfiguration:nil];
    self.camera.torchMode=AVCaptureTorchModeOn;
    [self.camera unlockForConfiguration];
}
self.currentState=STATE_SAMPLING;
// stop the app from sleeping
[UIApplication sharedApplication].idleTimerDisabled = YES;
}

快速翻译

// we're now sampling from the camera
enum CurrentState {
case statePaused
case stateSampling
}
var currentState = CurrentState.stateSampling
func setState(state: CurrentState){
            switch state
            {
            case .statePaused:
                // what goes here? Something like this?
            UIApplication sharedApplication.idleTimerDisabled = false
            case .stateSampling:
                // what goes here? Something like this?
            UIApplication sharedApplication.idleTimerDisabled = true
        }
        }
        // what goes here? Something like this?            
        currentState = CurrentState.stateSampling

Answer 1

您没有提供翻译后的 Swift 枚举的外观，所以我将定义一个似乎合适的枚举。假设您的枚举如下所示：

enum CurrentState 
{
    case statePaused
    case stateSampling
}

如果您有类型 CurrentState 的变量，例如您的currentState字段，

您可以给它一个这样的值：

currentState = CameraState.stateSampling

在 Swift 中，枚举被视为具有类型安全的真实对象，因此如果将对象声明为枚举类型，则可以使用较短的点语法，如下所示：

currentState = .stateSampling

在实际的 Swift 文档中有更多信息：

https://developer.apple.com/library/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Enumerations.html

更新

似乎您只是在询问如何设置UIApplication sharedApplication单例的idleTimerDisabled属性。你这样做是这样的：

UIApplication.sharedApplication().idleTimerDisabled = false