我在导航堆栈上有两个视图控制器。在第一个视图控制器中，我有一个方法可以显示一个警报，让您访问网站并离开应用程序。如果他们单击“否”，则不会发生任何事情，如果“是”，则会打开链接。这一切都有效。我现在的问题是，如果我想从导航堆栈上的第二个视图控制器调用此方法，我的第一个视图控制器会被释放，并且委托永远不会被调用。这是正在发生的事情的一些伪代码。
在 SecondView 控制器中：
- (void)TargetSelectionPressed:(NSNotification *)notification {
FirstViewController *dummyCtlr = nil;
BOOL shouldPushToFistCtlr = NO;
NSArray *controllers = [[NSArray alloc] initWithArray:[self.navigationController viewControllers]];
for (UIViewController *ctlr in controllers) {
if ([ctlr isKindOfClass:[FirstViewController class]]) {
dummyCtlr = (FirstViewController *)ctlr;
break;
}
}
if (dummyCtlr == nil) {
FirstViewController *gtc = [[[FirstViewController alloc] init] autorelease];
dummyCtlr = gtc;
shouldPushToFistCtlr = YES;
}
switch (targetSelection) {
case TARGET_LOCATION:
break;
case TARGET_CONDITION: {
if (shouldPushToGTC) {
[self.navigationController pushViewController:dummyCtlr animated:YES];
}
else {
[self.navigationController popToViewController:dummyCtlr animated:YES];
}
break;
}
case TARGET_LINK: {
[dummyCtlr BuildURL:link];
break;
}
default:
break;
}
[controllers release];
}
第一视图控制器
- (void)BuildURL:(NSString* )link {
self.ExternalLink = link; NSString *message = [[NSString alloc] initWithFormat:@"Would you like to open %@ in Safari?", link];
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Open Safari" message:message delegate:self cancelButtonTitle:@"No" otherButtonTitles:@"Yes", nil];
[alert show];
self.SafariAlertView = alert;
self.SafariAlertView.delegate = self;
[alert release];
[message release];
}
- (void)dealloc {
[safariAlertView release];
self.SafariAlertView.delegate = nil;
[super dealloc];
}