【转】iOS，搜索标签布局

前一阵时间，看过这样一个demo，代码不多，但是简洁易懂。

转自：

//  代码地址: https://github.com/iphone5solo/PYSearch

//  代码地址: http://www.code4app.com/thread-11175-1-1.html

/**  添加和布局标签 */
- (NSArray *)addAndLayoutTagsWithTagsContentView:(UIView *)contentView tagTexts:(NSArray<NSString *> *)tagTexts;
{
    // 清空标签容器的子控件
    [contentView.subviews makeObjectsPerformSelector:@selector(removeFromSuperview)];
    // 添加热门搜索标签
    NSMutableArray *tagsM = [NSMutableArray array];
    for (int i = 0; i < tagTexts.count; i++) {
        UILabel *label = [self labelWithTitle:tagTexts[i]];
        [label addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tagDidCLick:)]];
        [contentView addSubview:label];
        [tagsM addObject:label];
    }
    
    // 计算位置
    CGFloat currentX = 0;
    CGFloat currentY = 0;
    CGFloat countRow = 0;
    CGFloat countCol = 0;
    
    // 调整布局
    for (UILabel *subView in tagsM) {
        // 当搜索字数过多，宽度为contentView的宽度
        if (subView.py_width > contentView.py_width) subView.py_width = contentView.py_width;
        if (currentX + subView.py_width + PYMargin * countRow > contentView.py_width) { // 得换行
            subView.py_x = 0;
            subView.py_y = (currentY += subView.py_height) + PYMargin * ++countCol;
            currentX = subView.py_width;
            countRow = 1;
        } else { // 不换行
            subView.py_x = (currentX += subView.py_width) - subView.py_width + PYMargin * countRow;
            subView.py_y = currentY + PYMargin * countCol;
            countRow ++;
        }
    }
    // 设置contentView高度
    contentView.py_height = CGRectGetMaxY(contentView.subviews.lastObject.frame);
    // 设置头部高度
    self.baseSearchTableView.tableHeaderView.py_height = self.headerContentView.py_height = CGRectGetMaxY(contentView.frame) + PYMargin * 2;
    // 重新赋值, 注意：当操作系统为iOS 9.x系列的tableHeaderView高度设置失效，需要重新设置tableHeaderView
    [self.baseSearchTableView setTableHeaderView:self.baseSearchTableView.tableHeaderView];
    return [tagsM copy];
}

/** 添加标签 */

- (UILabel *)labelWithTitle:(NSString *)title

{

    UILabel *label = [[UILabel alloc] init];

    label.userInteractionEnabled = YES;

    label.font = [UIFont systemFontOfSize:12];

    label.text = title;

    label.textColor = [UIColor grayColor];

    label.backgroundColor = [UIColor py_colorWithHexString:@"#fafafa"];

    label.layer.cornerRadius = 3;

    label.clipsToBounds = YES;

    label.textAlignment = NSTextAlignmentCenter;

    [label sizeToFit];

    label.py_width += 20;

    label.py_height += 14;

    return label;

}