关于NavigationItem.rightBarButtonItem设置

转自：http://blog.csdn.net/zhuzhihai1988/article/details/7701998

第一种：

UIImage *searchimage=[UIImage imageNamed:@"search.png"];

UIBarButtonItem *barbtn=[[UIBarButtonItem alloc] initWithImage:nil style:UIBarButtonItemStyleDone target:self action:@selector(searchprogram)];

barbtn.image=searchimage;

self.navigationItem.rightBarButtonItem=barbtn;

这种设置出来的外观不好控制

第二种：

UIButton*rightButton = [[UIButtonalloc]initWithFrame:CGRectMake(0,0,30,30)];

[rightButtonsetImage:[UIImageimageNamed:@"search.png"]forState:UIControlStateNormal];

[rightButtonaddTarget:selfaction:@selector(searchprogram)forControlEvents:UIControlEventTouchUpInside];

UIBarButtonItem*rightItem = [[UIBarButtonItemalloc]initWithCustomView:rightButton];

[rightButton release];

self.navigationItem.rightBarButtonItem= rightItem;

[rightItem release];

这种图片将填满button，大小可控

第三种：

UIBarButtonItem *anotherButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemBookmarks target:self action:@selector(methodtocall:) ];

如何让navigationItem.rightBarButtonItem隐藏消失？

self.navigationItem.rightBarButtonItem=nil；

即可实现