iOS statusBar 状态栏定制

 1 UIWindow * statusWindow = [[UIWindow alloc] initWithFrame:[UIApplication sharedApplication].statusBarFrame];
 2 [statusWindow setWindowLevel:UIWindowLevelStatusBar + 1];
 3 [statusWindow setBackgroundColor:[UIColor clearColor]];
 4
 5 UILabel * statusLabel = [[UILabel alloc] initWithFrame:statusWindow.bounds];
 6 statusLabel.text = @"RSSI:";
 7 statusLabel.textColor = [UIColor blueColor];
 8 statusLabel.textAlignment = NSTextAlignmentCenter;
 9 statusLabel.backgroundColor = [UIColor redColor];
10
11 [statusWindow addSubview:statusLabel];
12 [statusWindow makeKeyAndVisible];