Display the multi-lines in the UILabel

To use NSString method, "sizeWithFont:constrainedToSize: lineBreakMode:"

It figure out the UILabel size to accommodate the long String.

//  init the content of string

NSString *string = @"Cocos2d-x open source project is C++ version of cocos2d-iphone. We focus on making cocos2d framework cross multiple platforms. Mobile games can be written on the top of cocos2d-x in C++ or Lua language, via the COMPLETELY SAME API as cocos2d-iphone, they can easily be built & run on iOS, Android, Samsung Bada and BlackBerry Tablet OS. Cocos2d-x also supports Windows & Linux, therefore we can debug source code easily and write editors on desktop operating systems."; 

// Determine the size of UILabel for the string

CGSize aSize = [string sizeWithFont: [UIFont systemFontOfSize:18] constrainedToSize:CGSizeMake(250.0, 999.0) lineBreakMode:UILineBreakModeWordWrap]; 

 // Declare UILabel,

UILabel *label = [[UILabel alloc] initWithFrame: CGRectMake(20, 20, aSize.width, aSize.height)]; 

 // init the label

label.backgroundColor = [UIColor grayColor]; 

label.textColor = [UIColor redColor]; 

label.font = UIFont systemFontOfSize:18;

label.lineBreakMode = UILineBreakModeWordWrap; 

label.text = string; 

label.numberOfLines = 0;  

[self.view addSubview:label];