效果圖

image

- (void)showCity:(NSString *)cityname  
{  
    //實(shí)現(xiàn)富文本  
    NSMutableAttributedString *string = [[NSMutableAttributedString alloc] initWithString:cityname attributes:nil];  
    //進(jìn)行圖文混排  
    NSTextAttachment *textAttachment = [[NSTextAttachment alloc] initWithData:nil ofType:nil];  
    textAttachment.image = [UIImage imageNamed:@"f_flagdown02@2x"];  
    textAttachment.bounds =CGRectMake(0,0, 11,8);  
    NSAttributedString * textAttachmentString = [NSAttributedString attributedStringWithAttachment:textAttachment];  
    //判斷選擇的城市名稱長度是否大于5個(gè)字符的長度，如果大于五個(gè)字符就取前四個(gè)字符，然后再在最后添加一個(gè)圖標(biāo)  
    if (string.length >=5) {  
        //去前四個(gè)字符  
        NSAttributedString *str = [string attributedSubstringFromRange:NSMakeRange(0,4)];  
        //將NSAttributedString類型轉(zhuǎn)換成NSString類型  
        NSString *cityString = [str string];  
        string = [[NSMutableAttributedString alloc] initWithString:[NSString stringWithFormat:@"%@..",cityString] attributes:nil];  
    }  
  
    //在城市名稱后插入圖片  
    [string insertAttributedString:textAttachmentString atIndex:string.length];  
    //自定義按鈕  
    UIButton *btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];  
    btn.frame =CGRectMake(0,0, 70,30);  
    [btn addTarget:self action:@selector(navBtnCLick)forControlEvents:UIControlEventTouchUpInside];  
    UILabel *lbText = [[UILabel alloc] initWithFrame:CGRectMake(0,0, btn.frame.size.width+10, btn.frame.size.height)];  
    lbText.attributedText = string;  
    lbText.textColor = [UIColorwhite Color];  
    lbText.font = [UIFont systemFontOfSize:13];  
    [btn addSubview:lbText];  
    btn.backgroundColor = [UIColor clearColor];  
    self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:btn];  
}