iphone - 充电完成前的剩余时间，iOS

Question

我正在使用:

UIDevice *myDevice = [UIDevice currentDevice];
[myDevice setBatteryMonitoringEnabled:YES];
float batLeft = [myDevice batteryLevel];
int i = [myDevice batteryState];    
int batinfo = batLeft * 100;

查找电池状态。我正在寻找如何找到充电完成前的剩余时间。例如:还剩 1 小时 20 分钟。如何以编程方式找到它？

Answer 1

我还没有在 official documentation 中找到任何方法, 既不在类倾销中，private header UIDevice 类。

所以我们必须想出一些办法。我目前想到的最佳“解决方案”类似于估算下载时间时采用的方法:计算下载/充电的平均速度，并将剩余量(数据或费用)除以该速度:

[UIDevice currentDevice].batteryMonitoringEnabled = YES;
float prevBatteryLev = [UIDevice currentDevice].batteryLevel;
NSDate *startDate = [NSDate date];

[[NSNotificationCenter defaultCenter]
    addObserver:self
       selector:@selector(batteryCharged)
           name:UIDeviceBatteryLevelDidChangeNotification
         object:nil
];

- (void)batteryCharged
{
    float currBatteryLev = [UIDevice currentDevice].batteryLevel;
    // calculate speed of chargement
    float avgChgSpeed = (prevBatteryLev - currBatteryLev) / [startDate timeIntervalSinceNow];
    // get how much the battery needs to be charged yet
    float remBatteryLev = 1.0 - currBatteryLev;
    // divide the two to obtain the remaining charge time
    NSTimeInterval remSeconds = remBatteryLev / avgChgSpeed;
    // convert/format `remSeconds' as appropriate
}