需求：将字符串：请阅读下面相关内容，进行下一步请点击：同意  ，中"同意"二字设置为红色

NSMutableAttributedString *str=[[NSMutableAttributedString alloc]initWithString:@"请阅读下面相关内容，进行下一步请点击：同意"];//NSRange：要改变的位置    NSRange redRange=NSMakeRange([[str string]rangeOfString:@"同意"].location, [[str string]rangeOfString:@"同意"].length);//value  ：要改变的颜色    [str addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:redRange];        [self.label setAttributedText:str];

需求：图片按规格剪切

UIImage *image1=[UIImage imageNamed:@"icon"];         CGRect frame = self.image1.bounds;//注意：这里是按照像素剪切，所以要在width 、height后面乘2    CGImageRef finalImgRef = CGImageCreateWithImageInRect(image1.CGImage, CGRectMake(0, 0, frame.size.width*2, frame.size.height*2));

需求：在每组TV的header位置添加自定义的UIView

-(UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section{    if (section==0) {        UIView *header =[[UIView alloc]initWithFrame:CGRectMake(0, 0, 320, 100)];        header.backgroundColor=[UIColor redColor];        return header;    }else if(section==1){       Header *hview=[[[NSBundle mainBundle]loadNibNamed:@"header" owner:self options:nil]lastObject];    return hview;  }else{    return [UIView alloc];}}-(CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section{    return 100;}//二者缺一不可