Problems with creating and using of delegate-protocols
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Published on 2010-01-23T14:48:21Z
Indexed on
2010/04/30
22:07 UTC
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Hello, I have the problem that I have created a delegate protocol, but the necessary methods are not executed, although I have implemented the protocol in my header file. Here are the detailed explanation:
I created an instance of my ViewController (TimeLineViewController), which will be displayed. This ViewController contains a UITableView, which in turn receives the individual Cells / Rows from one instance of my TableViewCell. So the ViewController creates an instance of TableCellView. The TableViewCell contains a UITextView, which contains web links. Now I want, that not safari opens the links, but my own built-in browser. Unfortunately TableViewCell can not open a new ViewController with a WebView, so I decided to create a delegate protocol.
The whole thing looks like this:
WebViewTableCellDelegate.h:
@protocol WebViewTableCellDelegate
-(void)loadWeb;
@end
Then I created a instance WebViewDelegate in the TableViewCell:
id <WebViewTableCellDelegate> _delegate;
In the .m of the TableViewCell:
@interface UITextView (Override)
@end
@class WebView, WebFrame;
@protocol WebPolicyDecisionListener;
@implementation UITextView (Override)
- (void)webView:(WebView *)webView decidePolicyForNavigationAction:(NSDictionary *)actionInformation request:(NSURLRequest *)request frame:(WebFrame *)frame decisionListener:(id < WebPolicyDecisionListener >)listener
{ NSLog(@"request: %@", request);
[_delegate loadWeb];
}
@end
- (void)setDelegate:(id <WebViewTableCellDelegate>)delegate{
_delegate = delegate;}
And in my TimeLineViewController I implemented the protocol with <> and the loadWeb-metode:
- (void)loadWeb{
WebViewController *web = [[WebViewController alloc] initWithNibName:nil bundle:nil];
web.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController: web animated:YES];
[web release];
}
And when the instance of the TableViewCell will be created in the TimelineViewController:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *MyIdentifier = @"MyIdentifier";
MyIdentifier = @"tableCell";
TableViewCell *cell = (TableViewCell *)[tableView dequeueReusableCellWithIdentifier:MyIdentifier];
if(cell == nil) {
[[NSBundle mainBundle] loadNibNamed:@"TableViewCell" owner:self options:nil];
cell = tableCell;}
[cell setDelegate:self];
//…
}
It is the first time I created a own delegate-protocol, so maybe there are stupid mistakes. Also I´m learnung Objective-C and programming generally only for 4 weeks.
Thanks for your help!
EDIT: I think i found the problem, but I dont know how to resolve it. I try to use [_delegate loadWeb]
; in the subclass of the UITextView (because that is the only way i can react on the weblinks) and the subclass can´t use [_delegate loadWeb];
. I tried this in a other methode and it worked.
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