我在topview中可以引用公共属性了

#import "ggsx.h"这个文件在这个类中是不是没有用到。

#import "Topview.h"

#import "ggsx.h"

@implementation Topview

-(id)initWithFrame:(CGRect)frame{

    self = [super initWithFrame:frame];

    if(self){

        self.backgroundColor = [UIColor blueColor];

    }

    return self;

}

-(void)setTitle:(NSString*)title{

    UILabel *label = [[UILabel alloc]init];

    label.text = title;

    label.backgroundColor = [UIColor clearColor];

    label.textColor = [UIColor whiteColor];

    UIFont *font = [UIFont systemFontOfSize:20.0];

    label.font = font;

    CGSize labelWH = [title sizeWithAttributes:[NSDictionary dictionaryWithObjectsAndKeys:font,NSFontAttributeName,nil]];

    label.frame = CGRectMake((UISCREEN_WIDTH-labelWH.width)/2, 20, labelWH.width, labelWH.height);

    [self addSubview:label];

}

@end

#import <UIKit/UIKit.h>

@interface Topview : UIView

-(void)setTitle:(NSString*)title;

@end