UIWebView 委托：未调用 webViewDidFinishLoad

Question

我尝试加载 UIWebView 数组并关联委托。

for (GDataXMLElement *post in array) {
    NSString *msg = [[[post elementsForName:@"message"] objectAtIndex:0] stringValue];
    UIWebView *web_view = [[UIWebView alloc] initWithFrame:CGRectZero];
    web_view.delegate = self;
    [web_view loadHTMLString:msg baseURL:nil];
    NSLog(@"Msg: %@", msg);
}

msg 是一些从 XML 读取的 HTML 代码。 XML 已正确加载（由NSLog 行验证）。然后在我的webViewDidFinishLoad:：

- (void)webViewDidFinishLoad:(UIWebView *)webView {
    CGRect frame = webView.frame;
    frame.size.height = 1;
    webView.frame = frame;
    CGSize fittingSize = [webView sizeThatFits:CGSizeZero];
    frame.size = fittingSize;
    webView.frame = frame;
    NSLog(@"WebView Height: %.1f", webView.frame.size.height);

    [webviews addObject:webView];
}

我会自动调整 Web 视图的大小并将它们添加到名为 webviews 的 NSMutableArray。但是，webViewDidFinishLoad 没有被调用。

在标题.h文件中，接口定义为：

@interface ViewController : UIViewController<UIWebViewDelegate>

我错过了什么？循环中的web_view 是否被处理掉了？

附言它看起来像这个 question 的副本，但它不是。

---

替代方法 1

声明于.h:

@property (nonatomic, weak) NSMutableArray *webviews;

然后实施：

for (GDataXMLElement *post in array) {
    NSString *msg = [[[post elementsForName:@"message"] objectAtIndex:0] stringValue];
    UIWebView *web_view = [[UIWebView alloc] initWithFrame:CGRectZero];
    web_view.delegate = self;
    [web_view loadHTMLString:msg baseURL:nil];
    NSLog(@"Msg: %@", msg);
    [self.webviews addObject:web_view];
}
- (void)webViewDidFinishLoad:(UIWebView *)webView {
    CGRect frame = webView.frame;
    frame.size.height = 1;
    webView.frame = frame;
    CGSize fittingSize = [webView sizeThatFits:CGSizeZero];
    frame.size = fittingSize;
    webView.frame = frame;
    NSLog(@"WebView Height: %.1f", webView.frame.size.height);
}

---

替代方法 2

我没有在for-loop中实例化UIWebView，而是将它放在头文件中。

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

然后改变for循环：

for (GDataXMLElement *post in array) {
    NSString *msg = [[[post elementsForName:@"message"] objectAtIndex:0] stringValue];
    web_view = [[UIWebView alloc] initWithFrame:CGRectZero];
    web_view.delegate = self;
    [web_view loadHTMLString:msg baseURL:nil];
    NSLog(@"Msg: %@", msg);
    [self.webviews addObject:web_view];
}

在这种方法中，只有最后一条消息的委托被调用。

---

总结和亮点：

我的目标：

1. 用可变大小的内容加载所有UIWebView
2. Web 视图应自动适应内容的大小（无需滚动）；这就是为什么需要webViewDidFinishLoad。
3. 在当前视图（或者可能是 UIScrollView）上正确排列 Web 视图，以使其不重叠。

Answer 1

你应该这样做，

@interface UIViewController <UIWebViewDelegate>
{

}
@property(nonatomic, strong)NSMutableArray *webViews;

@end

////////////////

@implementation UIViewController

-(void)viewDidLoad
{
  [super viewDidLoad];

   webViews = [[NSMutableArray alloc] init];

   for (GDataXMLElement *post in array) 
   {
    NSString *msg = [[[post elementsForName:@"message"] objectAtIndex:0] stringValue];
    UIWebView *web_view = [[UIWebView alloc] initWithFrame:CGRectZero];
    web_view.delegate = self;
    [web_view loadHTMLString:msg baseURL:nil];
    NSLog(@"Msg: %@", msg);
    [self.webViews addObject:web_view];

     //i don't know why would  you not add these web-views on the view controller,
     // but still, here is the addition of these.
     [self.view addSubView:web_view];
    }
}

@end

这应该使 web 视图在加载时正确调用委托。

Answer 2

如果您使用 ARC，则 web_view 在 for 循环结束时被释放。

Answer 3

这是我的最终解决方案（希望对其他人有用）：

在 Storyboard 中，我在视图控制器中添加了 UIScrollView，并将其与 IBOutlet 链接。

头文件：

#import <UIKit/UIKit.h>
#import "GDataXMLNode.h"

@interface ViewController : UIViewController<UIWebViewDelegate> {
    IBOutlet UIScrollView *scroll_view;
}
@property (nonatomic, strong) UIWebView *web_view;

@end

实施文件：

float currentY;
NSArray *array;
int count;
GDataXMLDocument *doc;

- (void)viewDidLoad
{
    [super viewDidLoad];

    currentY = 0;
    count = 0;
    [self loadXML];
}

- (void)loadXML {
   // Some codes to load the XML contents into array variable
   [self loadWebView];
}

- (void)loadWebView {
    if(count < array.count) {
        GDataXMLElement *post = [array objectAtIndex:count];
        NSString *msg = [[[post elementsForName:@"message"] objectAtIndex:0] stringValue];
        count++;
        self.web_view = [[UIWebView alloc] initWithFrame:CGRectMake(10, currentY, 300, 1.0f)];
        self.web_view.delegate = self;
        [self.web_view setHidden:YES];
        [self.web_view loadHTMLString:msg baseURL:nil];
        [scroll_view addSubview:self.web_view];
    } else {
        // end the process
        [scroll_view setContentSize:CGSizeMake(320, currentY + 30)];
        return;
    }
}

- (void)webViewDidFinishLoad:(UIWebView *)webView {
    CGRect frame = webView.frame;
    frame.size.height = 1;
    webView.frame = frame;
    CGSize fittingSize = [webView sizeThatFits:CGSizeZero];
    frame.size = fittingSize;
    webView.frame = frame;
    [webView setHidden:NO];

    currentY += webView.frame.size.height + 20.0f; // 20.0f is spaces between posts

    NSLog(@"WebView Height: %.1f", webView.frame.size.height);
    [self loadWebView];
}