單擊按鈕后，在UIWebView中打開網頁

Question

我需要幫助。 我有兩個按鈕，每個按鈕都需要在UIWebView中打開不同的網頁（例如：button1打開網站apple.com，button2打開google.com）。 我找不到任何對我有幫助的教程。 尋求幫助（我使用情節提要） 。

有我的代碼，但出了點問題，因為我只看到黑屏（單擊按鈕后）

TabulkaViewController.m

    UIButton *myButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    myButton.frame = CGRectMake(10, 240, 300, 35);
    [myButton setTitle:@"Buttonone" forState:UIControlStateNormal];
    [myButton addTarget:self action:@selector(myButtonClick:) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview: myButton];
}
-(void) myButtonClick:(NSString *)myString
{   
    NSURL *url = [NSURL URLWithString:@"http://www.apple.com/"];
    WebViewController *viewWeb = [[WebViewController alloc] initWithURL:url andTitle:@"Apple"];
    [self presentViewController:viewWeb animated:YES completion:nil];

}

WebViewController.h

#import <UIKit/UIKit.h>

@interface WebViewController : UIViewController <UIWebViewDelegate>
{
NSURL *theURL;
NSString *theTitle;
IBOutlet UINavigationItem *webTitle;
}
- (id)initWithURL:(NSURL *)url;
- (id)initWithURL:(NSURL *)url andTitle:(NSString *)string;
@property (strong, nonatomic) IBOutlet UIWebView *viewWeb;
@end

WebViewController.m

#import "WebViewController.h"
@implementation WebViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    webTitle.title = theTitle;
    NSURLRequest *requestObject = [NSURLRequest requestWithURL:theURL];
    [_viewWeb loadRequest:requestObject];
}
- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
}
- (id)initWithURL:(NSURL *)url andTitle:(NSString *)string {
    if( self = [super init] ) {
        theURL = url;
        theTitle = string;
    }
    return self;
}
-(id)initWithURL:(NSURL *)url {
    return [self initWithURL:url andTitle:nil];
}
- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
    _viewWeb.delegate = nil;
    [_viewWeb stopLoading];
}
@end

Answer 1

使用情節提要時，如果將項目文件上載到某處，將很有幫助。

但是根據經驗，您需要將webView委托設置為類WebViewController

您可以通過在viewDidLoad中添加以下代碼來做到這一點：

self.webView.delegate = self;

那么您必須實現shouldStartLoadWithRequest委托調用，這是一個好的開始。

- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType
{ 
    return YES;
}

讓我知道是否可以解決。

編輯：檢查項目后，將WebViewController- > viewDidLoad更改為此：

- (void)viewDidLoad
{
    [super viewDidLoad];
    // init webview
    _viewWeb = [[UIWebView alloc] initWithFrame:self.view.frame];

    _viewWeb.delegate = self;

    // add it to this controller's view
    [self.view addSubview:_viewWeb];

    webTitle.title = theTitle;
    NSURLRequest *requestObject = [NSURLRequest requestWithURL:theURL];

    [self.viewWeb loadRequest:requestObject];
}

您的_viewWeb並未按照我的懷疑進行初始化，請參閱有關如何初始化它以及如何將其添加到WebViewController的評論

EDIT2：添加了使Web視圖全屏顯示的約束，建議您閱讀有關Apple文檔中自動布局的內容

- (void)viewDidLoad
{
    [super viewDidLoad];
    // init webview
    _viewWeb = [[UIWebView alloc] initWithFrame:self.view.frame];

    _viewWeb.delegate = self;

    // add it to this controller's view
    [self.view addSubview:_viewWeb];


    // add constraints
    NSDictionary* dict = @{@"viewWeb":_viewWeb};
    _viewWeb.translatesAutoresizingMaskIntoConstraints = NO;
    NSArray* constraints = [NSLayoutConstraint constraintsWithVisualFormat:@"H:|-0-[viewWeb]-0-|" options:0 metrics:nil views:dict];
    [self.view addConstraints:constraints];
    constraints = [NSLayoutConstraint constraintsWithVisualFormat:@"V:|-0-[viewWeb]-0-|" options:0 metrics:nil views:dict];
    [self.view addConstraints:constraints];

    webTitle.title = theTitle;
    NSURLRequest *requestObject = [NSURLRequest requestWithURL:theURL];

    [self.viewWeb loadRequest:requestObject];
}