self.catBtn = [UIButtonbuttonWithType:UIButtonTypeSystem];
self.catBtn.backgroundColor = [UIColorredColor];
self.catBtn.frame = CGRectMake(75, 22, 90, 30);
[self.catBtnsetTitle:@"Protocol"forState:UIControlStateNormal];
self.catBtn.titleLabel.tintColor = [UIColorblackColor];
[self.catBtnaddTarget:self
action:@selector(selectDisplay)
forControlEvents:UIControlEventTouchDown];
[navBar addSubview:self.catBtn];