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Swift获取当前页面帧数值FPS，判断当前页面流畅程度。
97C8.tmp.jpg
代码
//
// V2FPSLabel.swift
// V2ex-Swift
//
// Created by huangfeng on 1/15/16.
// Copyright © 2016 Fin. All rights reserved.
//
import UIKit
//重写自 YYFPSLabel
//https://github.com/ibireme/YYText/blob/master/Demo/YYTextDemo/YYFPSLabel.m
class V2FPSLabel: UILabel {
private var _link :CADisplayLink?
private var _count:Int = 0
private var _lastTime:NSTimeInterval = 0
private let _defaultSize = CGSizeMake(55, 20);
override init(frame: CGRect) {
var targetFrame = frame
if frame.size.width == 0 && frame.size.height == 0{
targetFrame.size = _defaultSize
}
super.init(frame: targetFrame)
self.layer.cornerRadius = 5
self.clipsToBounds = true
self.textAlignment = .Center
self.userInteractionEnabled = false
self.textColor = UIColor.whiteColor()
self.backgroundColor = UIColor(white: 0, alpha: 0.7)
self.font = UIFont(name: "Menlo", size: 14)
weak var weakSelf = self
_link = CADisplayLink(target: weakSelf!, selector:#selector(V2FPSLabel.tick(_:)) );
_link!.addToRunLoop(NSRunLoop .mainRunLoop(), forMode:NSRunLoopCommonModes)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
func tick(link:CADisplayLink) {
if _lastTime == 0 {
_lastTime = link.timestamp
return
}
_count += 1
let delta = link.timestamp - _lastTime
if delta < 1 {
return
}
_lastTime = link.timestamp
let fps = Double(_count) / delta
_count = 0
let progress = fps / 60.0;
self.textColor = UIColor(hue: CGFloat(0.27 * ( progress - 0.2 )) , saturation: 1, brightness: 0.9, alpha: 1)
self.text = "\(Int(fps+0.5))FPS"
}
}
