//
//  OpenWebViewController.m
//  Treasure
//
//  Created by 藍藍色信子 on 16/7/29.
//  Copyright ? 2016年 GY. All rights reserved.
//

#import "ZTOpenWebViewController.h"
#import <WebKit/WebKit.h>@interface ZTOpenWebViewController ()<WKNavigationDelegate>
//{
//    //網頁視圖
//    UIWebView * _webView;
//}
@property (strong, nonatomic) WKWebView *webView;@property (strong, nonatomic) UIProgressView *progressView;@end@implementation ZTOpenWebViewController- (void)viewDidLoad {[super viewDidLoad];//    //取消導航欄的影響self.automaticallyAdjustsScrollViewInsets = NO;self.view.backgroundColor = [UIColor whiteColor];//[SVProgressHUD show];//實例化
    [self createWebView];[self creatCustomProgressView];
}-(void)creatCustomProgressView{//增加加載進度條// KVO，監聽webView屬性值得變化(estimatedProgress,title為特定的key)[_webView addObserver:self forKeyPath:@"estimatedProgress" options:NSKeyValueObservingOptionNew context:nil];[_webView addObserver:self forKeyPath:@"title" options:NSKeyValueObservingOptionNew context:nil];// UIProgressView初始化self.progressView = [[UIProgressView alloc] initWithProgressViewStyle:UIProgressViewStyleDefault];self.progressView.frame = CGRectMake(0, 0, _webView.frame.size.width, 5);self.progressView.trackTintColor = [UIColor clearColor]; // 設置進度條的色彩self.progressView.progressTintColor = [UIColor magentaColor];// 設置初始的進度，防止用戶進來就懵逼了（微信大概也是一開始設置的10%的默認值）[self.progressView setProgress:0.1 animated:YES];[_webView addSubview:self.progressView];
}- (void)viewWillAppear:(BOOL)animated
{[self.navigationController setNavigationBarHidden:NO animated:NO];[super viewWillAppear:YES];
}
- (void)viewWillDisappear:(BOOL)animated
{[SVProgressHUD dismiss];[super viewWillDisappear:animated];
}- (void)createWebView
{_webView = [[WKWebView alloc]initWithFrame:self.view.bounds];[self.view addSubview:_webView];//調整適應比例//_webView.scalesPageToFit = YES;//設置代理_webView.navigationDelegate = self;[[NSURLCache sharedURLCache] removeAllCachedResponses];[_webView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:self.urlStr] cachePolicy:NSURLRequestReloadIgnoringLocalAndRemoteCacheData timeoutInterval:10.0]];}
#pragma mark - WKWebView NavigationDelegate//WKNavigationDelegate
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler {//NSLog(@"是否允許這個導航");
    decisionHandler(WKNavigationActionPolicyAllow);
}- (void)webView:(WKWebView *)webView decidePolicyForNavigationResponse:(WKNavigationResponse *)navigationResponse decisionHandler:(void (^)(WKNavigationResponsePolicy))decisionHandler {//    Decides whether to allow or cancel a navigation after its response is known.//NSLog(@"知道返回內容之后，是否允許加載，允許加載");
    decisionHandler(WKNavigationResponsePolicyAllow);
}
- (void)webView:(WKWebView *)webView didStartProvisionalNavigation:(null_unspecified WKNavigation *)navigation {//NSLog(@"開始加載");//self.progress.alpha  = 1;//[SVProgressHUD show];[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;}- (void)webView:(WKWebView *)webView didReceiveServerRedirectForProvisionalNavigation:(null_unspecified WKNavigation *)navigation {//NSLog(@"跳轉到其他的服務器");
    
}- (void)webView:(WKWebView *)webView didFailProvisionalNavigation:(null_unspecified WKNavigation *)navigation withError:(NSError *)error {//NSLog(@"網頁由于某些原因加載失敗");//[SVProgressHUD dismiss];//self.progress.alpha  = 0;[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
}
- (void)webView:(WKWebView *)webView didCommitNavigation:(null_unspecified WKNavigation *)navigation {//NSLog(@"網頁開始接收網頁內容");
}
- (void)webView:(WKWebView *)webView didFinishNavigation:(null_unspecified WKNavigation *)navigation {//NSLog(@"網頁導航加載完畢");//[SVProgressHUD dismiss];[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;self.title = webView.title;[webView evaluateJavaScript:@"document.title" completionHandler:^(id _Nullable ss, NSError * _Nullable error) {//NSLog(@"----document.title:%@---webView title:%@",ss,webView.title);
    }];//self.progress.alpha  = 0;
    
}- (void)webView:(WKWebView *)webView didFailNavigation:(null_unspecified WKNavigation *)navigation withError:(NSError *)error {//NSLog(@"加載失敗,失敗原因:%@",[error description]);//self.progress.alpha = 0;
}
- (void)webViewWebContentProcessDidTerminate:(WKWebView *)webView {//NSLog(@"網頁加載內容進程終止");
}#pragma mark - KVO監聽
// 第三部：完成監聽方法
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {if ([object isEqual:_webView] && [keyPath isEqualToString:@"estimatedProgress"]) { // 進度條
        CGFloat newprogress = [[change objectForKey:NSKeyValueChangeNewKey] doubleValue];//NSLog(@"打印測試進度值：%f", newprogress);if (newprogress == 1) { // 加載完成// 首先加載到頭
            [self.progressView setProgress:newprogress animated:YES];// 之后0.3秒延遲隱藏__weak typeof(self) weakSelf = self;dispatch_after(dispatch_time(DISPATCH_TIME_NOW, 0.3 * NSEC_PER_SEC), dispatch_get_main_queue(), ^{weakSelf.progressView.hidden = YES;[weakSelf.progressView setProgress:0 animated:NO];});} else { // 加載中self.progressView.hidden = NO;[self.progressView setProgress:newprogress animated:YES];}} else if ([object isEqual:_webView] && [keyPath isEqualToString:@"title"]) { // 標題//self.title = _webView.title;} else { // 其他
        [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];}
}-(void)dealloc{NSLog(@"webVC dealloc = %@",self);[_webView removeObserver:self forKeyPath:@"estimatedProgress"];[_webView removeObserver:self forKeyPath:@"title"];
}- (void)didReceiveMemoryWarning {[super didReceiveMemoryWarning];// Dispose of any resources that can be recreated.
}/*#pragma mark - Navigation// In a storyboard-based application, you will often want to do a little preparation before navigation- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {// Get the new view controller using [segue destinationViewController].// Pass the selected object to the new view controller.}*/@end

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轉載于:https://www.cnblogs.com/liuw-flexi/p/9593716.html

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