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我試圖讓電池電量/狀態如下:確定準確的iPhone電池電量
- (void) viewWillAppear: (BOOL) animated{
[self viewWillAppear:animated];
// Battery state
[self batteryStatus];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(batteryStatus) name:UIDeviceBatteryLevelDidChangeNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(batteryStatus) name:UIDeviceBatteryStateDidChangeNotification object:nil];
}
- (void)batteryStatus
{
NSArray *batteryStatus = [NSArray arrayWithObjects:
@"Battery status is unknown.",
@"Battery is in use (discharging).",
@"Battery is charging.",
@"Battery is fully charged.", nil];
if ([[UIDevice currentDevice] batteryState] == UIDeviceBatteryStateUnknown)
{
[textViewStatus setText:[batteryStatus objectAtIndex:0]];
NSLog(@"%@", [batteryStatus objectAtIndex:0]);
}
else
{
NSString *msg = [NSString stringWithFormat:@"Battery charge level: %0.2f%%\n%@", [[UIDevice currentDevice] batteryLevel] * 100,[batteryStatus objectAtIndex:[[UIDevice currentDevice] batteryState]] ];
[textViewStatus setText:msg];
NSLog(@"%@", msg);
}
}
在電池電量但是,我沒有得到改變,而值不準確。
- (void) viewWillAppear:(BOOL)animated {
UIDevice *device = [UIDevice currentDevice];
device.batteryMonitoringEnabled = YES;
textViewStatus.text = [NSString stringWithFormat:@"%.2f", device.batteryLevel];
[device addObserver:self forKeyPath:@"batteryLevel" options:0x0 context:nil];
[super viewWillAppear:animated];
}
- (void) viewDidDisappear:(BOOL)animated {
UIDevice *device = [UIDevice currentDevice];
device.batteryMonitoringEnabled = NO;
[device removeObserver:self forKeyPath:@"batteryLevel"];
[super viewDidDisappear:animated];
}
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
UIDevice *device = [UIDevice currentDevice];
if ([object isEqual:device] && [keyPath isEqual:@"batteryLevel"]) {
NSLog(@"Battery level :%f",device.batteryLevel);
textViewStatus.text = [NSString stringWithFormat:@"%.2f", device.batteryLevel];
}
}
任何想法?
感謝您的回覆。是的,它以5%的間隔顯示變化。但是我想要展示每個級別的變化。 –
@sandhya這是SDK的限制和Apple選擇設計它的方式。根據蘋果的文檔... '電池電量變化的通知不多於每分鐘一次# –
當應用程序關閉,那麼我們可以使用這些通知嗎?我不確定這是爲什麼問你.. – Apple