基本用法示例
- (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view. UIWebView * webView = [[UIWebView alloc]initWithFrame:CGRectMake(0, 20, ScreenWidth, ScreenHeight-20)]; // 自动队页面进行缩放以适应屏幕 webView.scalesPageToFit = YES; webView.userInteractionEnabled = YES; webView.opaque = YES; [self.view addSubview:webView]; NSURL * url = [NSURL URLWithString:@"http://www.youku.com"]; NSURLRequest * request = [NSURLRequest requestWithURL:url]; [webView loadRequest:request]; // NSString * myHT = @"优酷"; // [webView loadHTMLString:myHT baseURL:url]; /* [webView goBack]; // 返回 [webView goForward]; // 前往 [webView reload]; [webView stopLoading]; */ webView.delegate = self; //移除滚动后的外边阴影 UIScrollView *scrollView = webView.scrollView; for (int i = 0; i < scrollView.subviews.count ; i++) { UIView *view = [scrollView.subviews objectAtIndex:i]; if ([view isKindOfClass:[UIImageView class]]) { view.hidden = YES ; } } } #pragma mark - UIWebViewDelegate - (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType{ /** * typedef NS_ENUM(NSInteger, UIWebViewNavigationType) { * UIWebViewNavigationTypeLinkClicked, * UIWebViewNavigationTypeFormSubmitted, * UIWebViewNavigationTypeBackForward, * UIWebViewNavigationTypeReload, * UIWebViewNavigationTypeFormResubmitted, * UIWebViewNavigationTypeOther }; */ NSLOG_FUNCTION; return YES; } // 开始加载 - (void)webViewDidStartLoad:(UIWebView *)webView{ NSLOG_FUNCTION; } // 完成加载 - (void)webViewDidFinishLoad:(UIWebView *)webView{ NSLOG_FUNCTION; } // 加载失败,弹出错误提示 - (void)webView:(UIWebView *)webView didFailLoadWithError:(NSError *)error{ UIAlertView *alterview = [[UIAlertView alloc] initWithTitle:@"" message:[error localizedDescription] delegate:nil cancelButtonTitle:nil otherButtonTitles:@"OK", nil]; [alterview show]; [alterview release]; NSLOG_FUNCTION; }
以下是关于它的一些使用技巧：
1.让网页适应手机屏幕宽度
如果用UIWebView显示一些pc站的网页，会发现网页会超出屏幕，显得很不好看，这时可以在webViewDidFinishLoad这个代理里面通过js添加一个meta：
- (void)webViewDidFinishLoad:(UIWebView *)webView { NSString *meta = [NSString stringWithFormat:@"document.getElementsByName("viewport")[0].content = "width=%f, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=no"", IPHONE_WIDTH]; [webView stringByEvaluatingJavaScriptFromString:meta]; }
注意：使用这个方法时要把UIWebView的scalesPageToFit设成NO
webView.scalesPageToFit = NO;
2.为网页中的图片添加点击事件，当点击图片时放大查看
思路是给每一个img标签添加onclick事件，在事件中把img的src属性封装成一个特殊的url，然后进行拦截
如果是通过loadHTMLString去加载网页的话，可以执行下面一句进行替换：
复制代码 代码如下:
html = [html stringByReplacingOccurrencesOfString:@"<img " withString:@"<img onclick="window.location.href=('http://src.'+this.src);" "];
如果是通过loadRequest，那就要再webViewDidFinishLoad中执行以下JS：
NSString *js = @"var imgs = document.getElementsByTagName("img");" "for(var i=0;i<imgs.length;i++){" " var img = imgs[i];" " img.onclick=function(){window.location.href=('http://src.'+this.src);}" "}"; [webView stringByEvaluatingJavaScriptFromString:js];
然后通过webview的代理方法去拦截，拿到图片的url，之后就可以做各种处理了
- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType { NSString *url = request.URL.absoluteString; if ([url hasPrefix:@"http://src."]) { url = [url stringByReplacingOccurrencesOfString:@"http://src." withString:@""]; // Do something.. return NO; } return YES; }
3.为UIWebView添加一个跟随网页滚动的页头
UIWebView里包含一个scrollview，可以向scrollview里添加一个页头以达到跟随网页滚动的效果
CGFloat headerHeight = 36.0f; // 注意：y坐标必须是负数，IPHONE_WIDTH是屏幕宽度 UIView *headerView = [[UIView alloc] initWithFrame:CGRectMake(0, -headerHeight, IPHONE_WIDTH, headerHeight)]; [_webView.scrollView addSubview:_headerView]; // 修改webView的scrollView的contentInset，让顶部留出一点空间 UIEdgeInsets edgeInset = _webView.scrollView.contentInset; _webView.scrollView.contentInset = UIEdgeInsetsMake(headerView.frameHeight, edgeInset.left, edgeInset.bottom, edgeInset.right);