UI基础 - UIWebView | 已弃用 | - 低头捡石頭

UI基础 - UIWebView | 已弃用 |

■ 简言

1. UIWebView 是开发中最常用的控件，它是内置的浏览器控件，可以用来浏览网页、打开文档等等，如 html、pdf、doc、ppt、txt、mp4..... 它在 iOS 12 之后弃用，取而代之的是 WKWebview。其内部会管理浏览器的导航动作

[webView goBack];     // 回退
[webView goForward];  // 前进
[webView reload];     //重载
[webView stopLoading];//取消载入内容

■ 使用方式

1. 默认展示百度网，并为导航栏添加了搜索框，可进行网站查询

 1 #import "ViewController.h"
 2 @interface ViewController ()<UIWebViewDelegate,UITextFieldDelegate>
 3 
 4 @property (nonatomic, strong) UIWebView *webView;
 5 @property (nonatomic, strong) UIActivityIndicatorView *activityIndicator; // loading 提示
 6 
 7 @property (strong, nonatomic) UITextField *aTextField;// 搜索框
 8 @property (strong, nonatomic) NSString *string;       // 搜索内容
 9 @property (strong, nonatomic) UIButton *connectBT;
10 
11 @end
12 
13 @implementation ViewController
14 
15 - (void)viewDidLoad {
16     [super viewDidLoad];
17     self.view.backgroundColor = [UIColor whiteColor];
18     self.navigationController.navigationBar.translucent = NO;
19     
20     self.webView = [[UIWebView alloc] initWithFrame:self.view.bounds];
21     _webView.scalesPageToFit = YES;// 自动对页面进行缩放以适应屏幕
22     self.webView.delegate = self;  // 代理
23     // 链接：百度
24     NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"https://www.baidu.com"]];
25     [self.webView loadRequest:request];
26     [self.view addSubview:self.webView];
27     
28     // 给导航栏添加 UITextField
29     self.aTextField = [[UITextField alloc] initWithFrame:CGRectMake(40, 10, 200, 20)];
30     _aTextField.borderStyle = UITextBorderStyleRoundedRect;
31     _aTextField.clearButtonMode = UITextFieldViewModeWhileEditing;
32     self.aTextField.delegate = self;
33     [self.navigationController.navigationBar addSubview:_aTextField];
34     
35     // 给导航栏添加 btn 按钮
36     _connectBT = [UIButton buttonWithType:UIButtonTypeSystem];
37     _connectBT.frame = CGRectMake(self.view.frame.size.width - 40 - 80, 0, 80, 40);
38     [_connectBT setTitle:@"Connect" forState:UIControlStateNormal];
39     [self.navigationController.navigationBar addSubview:_connectBT];
40     [_connectBT addTarget:self action:@selector(getConnect) forControlEvents:UIControlEventTouchUpInside];
41 }
42 
43 #pragma mark - <UIWebViewDelegate>
44 // 网页开始加载时触发
45 -(void)webViewDidStartLoad:(UIWebView *)webView{
46     
47     self.aTextField.text = [[self.string componentsSeparatedByString:@"//"] lastObject];
48     
49     // 遮罩
50     UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
51     [view setBackgroundColor:[UIColor blackColor]];
52     [view setAlpha:0.1];
53     view.tag = 108;
54     [self.view addSubview:view];
55     
56     // 人见人爱的菊花
57     self.activityIndicator = [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(0, 0, 32, 32)];
58     [_activityIndicator setCenter:view.center];
59     [_activityIndicator setActivityIndicatorViewStyle:UIActivityIndicatorViewStyleWhite];
60     [view addSubview:_activityIndicator];
61     [_activityIndicator startAnimating];
62 }
63 
64 // 网页加载完成时调用
65 -(void)webViewDidFinishLoad:(UIWebView *)webView{
66     [self removeShadeView];
67 }
68 
69 // 网页加载错误的时触发
70 -(void)webView:(UIWebView *)webView didFailLoadWithError:(NSError *)error{
71     NSLog(@"__error：%@",error);
72     [self removeShadeView];
73 }
74 
75 #pragma mark - <UITextFieldDelegate>
76 // 键盘回收
77 - (BOOL)textFieldShouldReturn:(UITextField *)textField{
78     
79     [textField resignFirstResponder];
80     return YES;
81 }
82 
83 #pragma mark - self_difined_methods
84 // 移除遮罩
85 -(void)removeShadeView{
86     [_activityIndicator stopAnimating];// 停止
87     UIView *view = (UIView *)[self.view viewWithTag:108];
88     [view removeFromSuperview];// 移除遮罩
89 }
90 
91 -(void)getConnect{
92     
93     self.string = [NSString stringWithFormat:@"https://%@",_aTextField.text];
94     NSURL *url = [NSURL URLWithString:_string];
95     NSURLRequest *request = [NSURLRequest requestWithURL:url];
96     [_webView loadRequest:request];
97 }
98 
99 @end

运行效果：初始化百度 | 搜索框知乎

2. 加载 PDF

 1 #import "ViewController.h"
 2 @interface ViewController ()<UIWebViewDelegate,UITextFieldDelegate>
 3 @property (nonatomic, strong) UIWebView *webView;
 4 @end
 5 
 6 @implementation ViewController
 7 
 8 - (void)viewDidLoad {
 9     [super viewDidLoad];
10     self.view.backgroundColor = [UIColor whiteColor];
11     
12     self.webView = [[UIWebView alloc] initWithFrame:self.view.bounds];
13     _webView.scalesPageToFit = YES;    // 自动对页面进行缩放以适应屏幕
14     _webView.detectsPhoneNumbers = YES;// 自动检测网页上的电话号码：单击可以拨打
15     self.webView.delegate = self;  // 代理
16     [self.view addSubview:self.webView];
17     
18 //    // 方式一
19 //    NSString *filePath = [[NSBundle mainBundle] pathForResource:@"Demo6P" ofType:@"pdf"];
20 //    NSURL *url = [NSURL fileURLWithPath:filePath];
21 //    NSURLRequest *request = [NSURLRequest requestWithURL:url];
22 //    [self.webView loadRequest:request];
23     
24     // 方式二
25     NSString *filePathB = [[NSBundle mainBundle] pathForResource:@"Demo6P" ofType:@"pdf"];
26     NSData *pdfData = [NSData dataWithContentsOfFile:filePathB];
27     [self.webView loadData:pdfData MIMEType:@"application/pdf" textEncodingName:@"utf-8" baseURL:nil];
28     
29 }