WKWebView 是IOS8新增的 Web浏览视图
WKWebView相对于UIWebView强大了很多,内存的消耗相对少了,所提供的接口也丰富了。
title,estimatedProgress是两个很有用的新API
#import "MYWebViewController.h"
#import <WebKit/WebKit.h>
@interface MYWebViewController ()
//进度条
@property (weak, nonatomic) IBOutlet UIProgressView
*progressView;
@property (nonatomic, weak) WKWebView *webView;
@end
@implementation MYWebViewController
/*
使用步骤
1.导入WebKit框架
2.导入WebKit/WebKit.h头文件
*/
- (void)viewDidLoad {
[superviewDidLoad];
//添加WKWebView
WKWebView*webView = [[WKWebViewalloc] initWithFrame:self.view.bounds];
_webView = webView;
[self.viewinsertSubview:webView atIndex:0];
//加载网页
NSURLRequest*request = [NSURLRequestrequestWithURL:_url];
[webViewloadRequest:request];
//KVO: 让self对象监听webView的estimatedProgress
[webView addObserver:selfforKeyPath:@"estimatedProgress"options:NSKeyValueObservingOptionNewcontext:nil];
}
// 只要监听的属性有新值就会调用
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary<NSString *,id>
*)change context:(void *)context
{
_progressView.progress= _webView.estimatedProgress;
_progressView.hidden= _progressView.progress>= 1;
}
// KVO一定要移除观察者
- (void)dealloc
{
[self.webViewremoveObserver:selfforKeyPath:@"estimatedProgress"];
}
@end