[__NSCFConstantString size]: unrecognized selector sent to instance 错误

因为使用时候的类型和初始化的对象类型不匹配造成的，例如

- (NSMutableDictionary *)getMenuItems

{

    NSArray *defaultTmp = [NSArray arrayWithObjects:@"menu_friend_icon@2x.png",@"menu_message_icon@2x.png", @"menu_announcemen_icon@2x.png",@"menu_album_icon@2x.png",@"menu_more_icon@2x.png",nil];

    self.menuitemDefaultImages = defaultTmp;

    NSArray *highlightTmp = [NSArray arrayWithObjects:@"menu_friend_onfocus_icon@2x.png",@"menu_message_onfocus_icon@2x", @"menu_announcemen_onfocus_icon@2x",@"menu_album_onfocus_icon@2x.png",@"menu_more_onfocus_icon@2x.png",nil];
    self.menuitemHighlightImages = highlightTmp;  ／／这里都是nsstring类型的名字

    

    NSArray *labelTmp = [NSArray arrayWithObjects:@"好友",@"消息", @"公告",@"相册",@"更多",nil];

    self.menuitemLabels = labelTmp;

    

    NSMutableDictionary *tmp = [NSMutableDictionary dictionary];

    [tmp setObject:self.menuitemDefaultImages forKey:@"Default"];

    [tmp setObject:self.menuitemHighlightImages forKey:@"Highlight"];

    [tmp setObject:self.menuitemLabels forKey:@"Labels"];

    self.menuitemDictionary = tmp;

    return self.menuitemDictionary;

}
self.selectedStatuImages = [[self.announce getMenuItems]objectForKey:@"Highlight"];

    

    switch (button.tag) {

        case 0:  //friends

        {

            self.friendBtn.selected = !self.friendBtn.selected;

            if (self.friendBtn.selected) {

                [self.friendBtn setImage:[self.selectedStatuImages objectAtIndex:0] forState:UIControlStateSelected]; ／／这里获取时候的setimage参数却是UIImage类型的，所以会报错。要修改成[button setBackgroundImage:[UIImage
imageNamed:[self.normalStatuImages objectAtIndex:index]] forState:UIControlStateNormal];

            }else{

            

                [self.friendBtn setImage:[self.normalStatuImages objectAtIndex:0] forState:UIControlStateNormal];

            }

            

            break;

        }