WKWebView添加进度条

• 代码如下

@interface ViewController () 
/**
 *  webView
 */
@property (nonatomic, strong) WKWebView *webView;
@property (strong, nonatomic) UIProgressView *progressView;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    [self.webView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"http://www.baidu.com"]]];
}

#pragma mark - WKWebView代理
// 如果不添加这个，那么wkwebview跳转不了AppStore
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler {
    if ([webView.URL.absoluteString hasPrefix:@"https://itunes.apple.com"]) {
        [[UIApplication sharedApplication] openURL:navigationAction.request.URL];
        decisionHandler(WKNavigationActionPolicyCancel);
    }else {
        decisionHandler(WKNavigationActionPolicyAllow);
    }
}

// 计算wkWebView进度条
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
    if (object == self.webView && [keyPath isEqualToString:@"estimatedProgress"]) {
        CGFloat newprogress = [[change objectForKey:NSKeyValueChangeNewKey] doubleValue];
        if (newprogress == 1) {
            self.progressView.hidden = YES;
            [self.progressView setProgress:0 animated:NO];
        }else {
            self.progressView.hidden = NO;
            [self.progressView setProgress:newprogress animated:YES];
        }
    }
}

// 记得取消监听
- (void)dealloc {
   [self.webView removeObserver:self forKeyPath:@"estimatedProgress"];
}

#pragma mark - lazy
- (WKWebView *)webView
{
    if(!_webView)
    {
        _webView = [[WKWebView alloc] initWithFrame:CGRectMake(0, 0, QQMScreenWidth, QQMScreenHeight)];
        _webView.navigationDelegate = self;
        [_webView addObserver:self forKeyPath:@"estimatedProgress" options:NSKeyValueObservingOptionNew context:nil];
        [self.view insertSubview:_webView belowSubview:self.progressView];
    }
    return _webView;
}

- (UIProgressView *)progressView
{
    if(!_progressView)
    {
        _progressView = [[UIProgressView alloc] initWithFrame:CGRectMake(0, QQMNavH + QQMStatusH, QQMScreenWidth, 0)];
        self.progressView.tintColor = [UIColor orangeColor];
        self.progressView.trackTintColor = [UIColor whiteColor];
        [self.view addSubview:self.progressView];
    }
    return _progressView;
}
@end