How to Call an application in my XCode project?

Question

Hi,

I want to know how to write a program in Objective-C language in XCode for iPhone OS, i want to call an application(Ex: hello world) from another application(its a calling application, whose functionality is just to call hello world application). how to give the path of hello world in the calling application and where to place my hello world application(i mean , should i import hello world in my project or just specify its URL in my calling application)..??Pls give a coding example???

Answer 1

See: iPhone App Programming Guide

This is what your second application must do to handle an open call from the first:

- (BOOL)application:(UIApplication *)application handleOpenURL:(NSURL *)url {
    if ([[url scheme] isEqualToString:@"todolist"]) {
        ToDoItem *item = [[ToDoItem alloc] init];
        NSString *taskName = [url query];
        if (!taskName || ![self isValidTaskString:taskName]) { // must have a task name
            [item release];
            return NO;
        }
        taskName = [taskName stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

        item.toDoTask = taskName;
        NSString *dateString = [url fragment];
        if (!dateString || [dateString isEqualToString:@"today"]) {
            item.dateDue = [NSDate date];
        } else {
            if (![self isValidDateString:dateString]) {
                [item release];
                return NO;
            }
            // format: yyyymmddhhmm (24-hour clock)
            NSString *curStr = [dateString substringWithRange:NSMakeRange(0, 4)];
            NSInteger yeardigit = [curStr integerValue];
            curStr = [dateString substringWithRange:NSMakeRange(4, 2)];
            NSInteger monthdigit = [curStr integerValue];
            curStr = [dateString substringWithRange:NSMakeRange(6, 2)];
            NSInteger daydigit = [curStr integerValue];
            curStr = [dateString substringWithRange:NSMakeRange(8, 2)];
            NSInteger hourdigit = [curStr integerValue];
            curStr = [dateString substringWithRange:NSMakeRange(10, 2)];
            NSInteger minutedigit = [curStr integerValue];

            NSDateComponents *dateComps = [[NSDateComponents alloc] init];
            [dateComps setYear:yeardigit];
            [dateComps setMonth:monthdigit];
            [dateComps setDay:daydigit];
            [dateComps setHour:hourdigit];
            [dateComps setMinute:minutedigit];
            NSCalendar *calendar = [NSCalendar currentCalendar];
            NSDate *itemDate = [calendar dateFromComponents:dateComps];
            if (!itemDate) {
                [dateComps release];
                [item release];
                return NO;
            }
            item.dateDue = itemDate;
            [dateComps release];
        }

        [(NSMutableArray *)self.list addObject:item];
        [item release];
        return YES;
    }
    return NO;
}

And the first app opens it like this:

NSURL *myURL = [NSURL URLWithString:@"todolist://www.acme.com?Quarterly%20Report#200806231300"];
[[UIApplication sharedApplication] openURL:myURL];