iOS學習之WebView的使用

標籤：ios   控制項   webview   uiwebview   

1、初始化WebView

- (void)viewDidLoad
{
    [super viewDidLoad];
    webView = [[UIWebView alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];
    NSURLRequest *request =[NSURLRequest requestWithURL:[NSURL URLWithString:@"http://www.baidu.com"]];
    [self.view addSubview: webView];
    [webView loadRequest:request];
}

2、

實現協議，在ViewController.h修改如下#import <UIKit/UIKit.h>


@interface ViewController : UIViewController<UIWebViewDelegate>
{
    UIWebView *webView;
}
@end

UIWebView中幾個重要的函數
1.- (void )webViewDidStartLoad:(UIWebView  *)webView   網頁開始載入的時候調用
2.- (void )webViewDidFinishLoad:(UIWebView  *)webView  網頁載入完成的時候調用
3.- (void)webView:(UIWebView *)webView  didFailLoadWithError:(NSError *)error 網頁載入錯誤的時候調用

先在viewDidLoad 的webView執行個體化下面加上

    [webView setDelegate:self];設定代理。這樣上面的三個方法才能得到回調。

3、載入等待頁面

- (void) webViewDidStartLoad:(UIWebView *)webView
{
    //建立UIActivityIndicatorView背底半透明View     
    UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];  
    [view setTag:108];  
    [view setBackgroundColor:[UIColor blackColor]];  
    [view setAlpha:0.5];  
    [self.view addSubview:view];  
    
    activityIndicator = [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, 32.0f, 32.0f)];  
    [activityIndicator setCenter:view.center];  
    [activityIndicator setActivityIndicatorViewStyle:UIActivityIndicatorViewStyleWhite];  
    [view addSubview:activityIndicator];  


    [activityIndicator startAnimating];
}

載入完成或失敗時，去掉loading效果

- (void) webViewDidFinishLoad:(UIWebView *)webView
{
    [activityIndicator stopAnimating];
    UIView *view = (UIView*)[self.view viewWithTag:108];
    [view removeFromSuperview];
    NSLog(@"webViewDidFinishLoad");


}
- (void) webView:(UIWebView *)webView didFailLoadWithError:(NSError *)error
{
    [activityIndicator stopAnimating];
    UIView *view = (UIView*)[self.view viewWithTag:108];
    [view removeFromSuperview];

}

著作權聲明：本文由http://blog.csdn.net/yangchen9931原創，歡迎轉載分享。請尊重作者勞動，轉載時保留該聲明和作者部落格連結，謝謝

iOS學習之WebView的使用