iOS开发中WebView的使用

痛定思痛。 2022-08-26 12:14 175阅读 0赞

iOS开发中WebView的使用

在AppDelegate.m文件中

#import "AppDelegate.h"
    #import "webTableViewController.h"
    @implementation AppDelegate
    
    - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
    {
        self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
        // Override point for customization after application launch.
        self.window.backgroundColor = [UIColor whiteColor];
        webTableViewController *web = [[webTableViewController alloc]init];
        self.window.rootViewController = web;
        [self.window makeKeyAndVisible];
        return YES;
    }

新键一个类命名为webTableViewController

webTableViewController.h

#import <UIKit/UIKit.h>
    
    @interface webTableViewController : UIViewController<UIWebViewDelegate>
    {
        IBOutlet UIWebView *webView;
        
        UIActivityIndicatorView *activityIndicatorView;
        UIView *opaqueView;
    }
    
    @end

webTableViewController.m

#import "webTableViewController.h"
    
    @interface webTableViewController ()
    
    @end
    
    @implementation webTableViewController
    - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
    {
        self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
        if (self) {
            // Custom initialization
        }
        return self;
    }
    
    - (void)viewDidLoad
    {
        [super viewDidLoad];
        webView = [[UIWebView alloc]initWithFrame:CGRectMake(0, 44, 320, 440)];
        [webView setUserInteractionEnabled:YES];//是否支持交互
        //[webView setDelegate:self];
        webView.delegate=self;
        [webView setOpaque:NO];//opaque是不透明的意思
        [webView setScalesPageToFit:YES];//自动缩放以适应屏幕
        [self.view addSubview:webView];
        
        //加载网页的方式
        //1.创建并加载远程网页
        NSURL *url = [NSURL URLWithString:@"http://www.baidu.com"];
        [webView loadRequest:[NSURLRequest requestWithURL:url]];
        //2.加载本地文件资源
       /* NSURL *url = [NSURL fileURLWithPath:filePath];
        NSURLRequest *request = [NSURLRequest requestWithURL:url];
        [webView loadRequest:request];*/
        //3.读入一个HTML，直接写入一个HTML代码
        //NSString *htmlPath = [[[NSBundle mainBundle]bundlePath]stringByAppendingString:@"webapp/loadar.html"];
        //NSString *htmlString = [NSString stringWithContentsOfURL:htmlPath encoding:NSUTF8StringEncoding error:NULL];
        //[webView loadHTMLString:htmlString baseURL:[NSURL fileURLWithPath:htmlPath]];
        
        opaqueView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 320, 480)];
        activityIndicatorView = [[UIActivityIndicatorView alloc]initWithFrame:CGRectMake(0, 0, 320, 480)];
        [activityIndicatorView setCenter:opaqueView.center];
        [activityIndicatorView setActivityIndicatorViewStyle:UIActivityIndicatorViewStyleWhite];
        [opaqueView setBackgroundColor:[UIColor blackColor]];
        [opaqueView setAlpha:0.6];
        [self.view addSubview:opaqueView];
        [opaqueView addSubview:activityIndicatorView];
        
        
    }
    
    -(void)webViewDidStartLoad:(UIWebView *)webView{
        [activityIndicatorView startAnimating];
        opaqueView.hidden = NO;
    }
    
    -(void)webViewDidFinishLoad:(UIWebView *)webView{
        [activityIndicatorView startAnimating];
        opaqueView.hidden = YES;
    }
    
    //UIWebView如何判断 HTTP 404 等错误
    -(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response{
        NSURL *url = [NSURL URLWithString:@"http://www.baidu.com"];
        NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *)response;
        if ((([httpResponse statusCode]/100) == 2)) {
            // self.earthquakeData = [NSMutableData data];
            [UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
            
            [ webView loadRequest:[ NSURLRequest requestWithURL: url]];
            webView.delegate = self;
        } else {
            NSDictionary *userInfo = [NSDictionary dictionaryWithObject:
                                      NSLocalizedString(@"HTTP Error",
                                                        @"Error message displayed when receving a connection error.")
                                                                 forKey:NSLocalizedDescriptionKey];
            NSError *error = [NSError errorWithDomain:@"HTTP" code:[httpResponse statusCode] userInfo:userInfo];
            
            if ([error code] == 404) {
                NSLog(@"xx");
                webView.hidden = YES;
            }
            
        }
    }
    - (void)didReceiveMemoryWarning
    {
        [super didReceiveMemoryWarning];
        // Dispose of any resources that can be recreated.
    }
    
    @end