iOS：Xcode Instruments的使用

星星月亮0

2881人浏览 · 2021-06-09 20:01:09

星星月亮0 · 2021-06-09 20:01:09 发布

返回上级目录：iOS 性能优化（一）：Improving Your App‘s Performance

文章目录

1.使用实例
- 1.1 Points of Inerest(标记代码执行的点和执行时间)
2.苹果官网资料
3.实际操作
- 3.1 时间段左右上下放大缩小

1.使用实例

1.1 Points of Inerest(标记代码执行的点和执行时间)

import MetricKit

class ViewController: UIViewController {
    
    static let startupActivities:StaticString = "viewDidLoad"
    let poiLog = OSLog(subsystem: "com.example.CocoaPictures", category: .pointsOfInterest)
    
    override func viewDidLoad() {
        super.viewDidLoad()
        os_signpost(.begin, log: self.poiLog, name: ViewController.startupActivities)
        for i in 0...100 {
            print(i)
        }
        os_signpost(.end, log: self.poiLog, name: ViewController.startupActivities)

在这里插入图片描述
代码出处：
Apple Developer: Reducing Your App’s Launch Time

1.1.1 oc版，+load方法

override class func load()在swift中不被允许

在这里插入图片描述

instruments测试截图：+load方法的执行在启动的Initializing - Static Runtime Initialization阶段

在这里插入图片描述

代码：用swift代码通过桥接文件来实现

import UIKit
import MetricKit

class XXYMetric: NSObject {
    
   static var startupActivities:StaticString = "didFinishLaunching"
   static var poiLog = OSLog(subsystem: "com.example.CocoaPictures", category: .pointsOfInterest)
    
    @objc class func start(str: String) {
        poiLog = OSLog(subsystem: str, category: .pointsOfInterest)
        os_signpost(.begin, log: poiLog, name: startupActivities)
        
    }
    
    @objc class func end(str: String) {
        poiLog = OSLog(subsystem: str, category: .pointsOfInterest)
        os_signpost(.end, log: poiLog, name: startupActivities)
    }

}

#import "XXYPerson.h"
#import "XCTEST_oc-Swift.h"

@implementation XXYPerson

+ (void)load {
    [XXYMetric startWithStr:@"load"];
    for (int i = 0; i < 1000; i++) {
        NSLog(@"%d",i);
    }
    [XXYMetric endWithStr:@"load"];
    
}

@end