iOS 獲取蜂窩網絡信號強度 包含iPhoneX XS XR XSMASX （最新）

1.雖然各種直接獲取信號強度的api都被封殺了。但是還有一個另類的黑魔法可以獲取到。那就是遍歷UIStatusBar了

網絡上有的文章寫的會崩潰 比如：

- (int)getSignalStrength{
    if (iPhoneX) {
        id statusBar = [[UIApplication sharedApplication] valueForKeyPath:@"statusBar"];
        id statusBarView = [statusBar valueForKeyPath:@"statusBar"];
        UIView *foregroundView = [statusBarView valueForKeyPath:@"foregroundView"];
        int signalStrength = 0;
        NSArray *subviews = [[foregroundView subviews][2] subviews];
        for (id subview in subviews) {
            if ([subview isKindOfClass:NSClassFromString(@"_UIStatusBarWifiSignalView")]) {
                signalStrength = [[subview valueForKey:@"numberOfActiveBars"] intValue];
                break;
            }else if ([subview isKindOfClass:NSClassFromString(@"_UIStatusBarStringView")]) {
                signalStrength = [[subview valueForKey:@"numberOfActiveBars"] intValue];
                break;
            }
        }
        return signalStrength;
    } }

實測 iPhoneXSMAX 的 _UIStatusBarStringView 里面沒有 numberOfActiveBars的值。所以又重新遍歷，再xcode中斷點看了一下。是需要在

_UIStatusBarPersistentAnimationView  這個圖下面去取值就可以了 。。即

- (int)getSignalStrength{
    if (iPhoneX) {
        id statusBar = [[UIApplication sharedApplication] valueForKeyPath:@"statusBar"];
        id statusBarView = [statusBar valueForKeyPath:@"statusBar"];
        UIView *foregroundView = [statusBarView valueForKeyPath:@"foregroundView"];
        int signalStrength = 0;
        NSArray *subviews = [[foregroundView subviews][2] subviews];
        for (id subview in subviews) {
            if ([subview isKindOfClass:NSClassFromString(@"_UIStatusBarWifiSignalView")]) {
                signalStrength = [[subview valueForKey:@"numberOfActiveBars"] intValue];
                break;
            }else if ([subview isKindOfClass:NSClassFromString(@"_UIStatusBarPersistentAnimationView")]) {
                signalStrength = [[subview valueForKey:@"numberOfActiveBars"] intValue];
                break;
            }
        }
        return signalStrength;
    } }