Question

I have two local .html files in the Resources folder. I’m trying to load them the following way, but only the final page loads. What am I doing wrong?

File = please_wait.html

This one does not work.

NSError *error;
NSString* path = [[NSBundle mainBundle] pathForResource:@"please_wait" ofType:@"html"];
NSString* htmlString = [NSString stringWithContentsOfFile:path encoding:NSUTF8StringEncoding error:&error];
[webView loadHTMLString:htmlString baseURL:[NSURL fileURLWithPath:path]];   

 //Big "do-while" loop here.  It works fine so I omitted it.

File = update_graph.html

This one does not work

 path = [[NSBundle mainBundle] pathForResource:@"update_graph" ofType:@"html"];
 htmlString = [NSString stringWithContentsOfFile:path encoding:NSUTF8StringEncoding error:&error];
 [webView loadHTMLString:htmlString baseURL:[NSURL fileURLWithPath:path]];

//Lots of code removed.  All works correctly and doesn't touch webview

This last one works perfectly. Google displays.

string = @"http://google.com";  
NSURL *url = [NSURL URLWithString: string];
NSURLRequest *requestObj = [NSURLRequest requestWithURL:url];
[webView loadRequest:requestObj];

Answer 1

It appears from your comment that your UIWebView loads just fine, but it does not get a chance to refresh itself on the screen until you exit your method. It is not enough to set a break point inside the method and wait for the view to load: you must exit the method before iOS realizes that it needs to call UIWebView‘s drawRect method.

To fix this, split your method in three parts, A B and C, and set UIWebView‘s delegate in A to invoke B on webViewDidFinishLoad:, and the delegate in B to call C.

Here is how to implement this: start with a delegate that can call a selector when the loading has completed:

@interface GoToNext : NSObject <UIWebViewDelegate> {
    id __weak target;
    SEL next;
}
-(id)initWithTarget:(id)target andNext:(SEL)next;
-(void)webViewDidFinishLoad:(UIWebView *)webView;
@end

@implementation GoNext
-(id)initWithTarget:(id)_target andNext:(SEL)_next {
    self = [super init];
    if (self) {
        target = _target;
        next = _next;
    }
    return self;
}
-(void)webViewDidFinishLoad:(UIWebView *)webView {
    #pragma clang diagnostic push
    #pragma clang diagnostic ignored "-Warc-performSelector-leaks"
    [target performSelector:next];
    #pragma clang diagnostic pop
}
@end

Now split your method into three parts – loading the first page, loading the second page, and loading the third page:

-(void)loadPleaseWait {
    NSError *error;
    NSString* path = [[NSBundle mainBundle] pathForResource:@"please_wait" ofType:@"html"];
    NSString* htmlString = [NSString stringWithContentsOfFile:path encoding:NSUTF8StringEncoding error:&error];
    webView.delegate = [[GoToNext alloc] initWithTarget:self andNext:@selector(loadUpdateGraph)];
    [webView loadHTMLString:htmlString baseURL:[NSURL fileURLWithPath:path]];
    // big do-while loop
}

-(void)loadUpdateGraph {
    NSError *error;
    NSString* path = [[NSBundle mainBundle] pathForResource:@"update_graph" ofType:@"html"];
    NSString* htmlString = [NSString stringWithContentsOfFile:path encoding:NSUTF8StringEncoding error:&error];
    webView.delegate = [[GoToNext alloc] initWithTarget:self andNext:@selector(loadGoogle)];
    [webView loadHTMLString:htmlString baseURL:[NSURL fileURLWithPath:path]];
    // Lots of code removed
}

-(void)loadGoogle {
    string = @"http://google.com";  
    NSURL *url = [NSURL URLWithString: string];
    NSURLRequest *requestObj = [NSURLRequest requestWithURL:url];
    [webView loadRequest:requestObj];
}