iPhone: objc_class_name_TTTabStrip symbol not found build error

I am trying to implement 'scrollview' effect in 'Tabbar' which has 'TabItems'. I found that the good example is from 'facebook' open source 'TTCatlog' project 'Tabs' section. So i included all the source from it to my project and trying to build it. I have followed the following links to go ahead on this: How to create a horizontal scrolling view on iPhone? source: http://github.com/facebook/three20/tree/master/samples/

My calling code is like below:

_tabBar1 = [[TTTabStrip alloc] initWithFrame:CGRectMake(10, 68, 300, 28)];
_tabBar1.tabItems = [NSArray arrayWithObjects:
                     [[[TTTabItem alloc] initWithTitle:@"Item 1"] autorelease],
                     [[[TTTabItem alloc] initWithTitle:@"Ite开发者_如何学运维m 2"] autorelease],
                     [[[TTTabItem alloc] initWithTitle:@"Item 3"] autorelease],
                     [[[TTTabItem alloc] initWithTitle:@"Item 4"] autorelease],
                     [[[TTTabItem alloc] initWithTitle:@"Item 5"] autorelease],
                     [[[TTTabItem alloc] initWithTitle:@"Item 6"] autorelease],
                     [[[TTTabItem alloc] initWithTitle:@"Item 7"] autorelease],
                     [[[TTTabItem alloc] initWithTitle:@"Item 8"] autorelease],
                     [[[TTTabItem alloc] initWithTitle:@"Item 9"] autorelease],
                     [[[TTTabItem alloc] initWithTitle:@"Item 10"] autorelease],
                     nil];
[self.navigationController.view addSubview:_tabBar1];

My project folder as like below:

..../iphone/MyProgram/MyProgram.xcodeproj

..../iphone/Three20/src/Three20....

In my project settings for header search path, I have

../Three20/src

But when i try to build it, it throws the following error:

"objc_class_name_TTTabStrip symbol not found" "objc_class_name_TTTabItem symbol not found" I see there, all these files (.h and .m) are availbale there.

Could someone please help what's wrong there and how do i get rid of this issue and continue working with it?

Generally this error throw due to you not importing the appropriate class where you want to implement the method of that class(like inheritance).

#import "your_class_name.h"

@class your_class_name