iOS开发 标签的实现

本文主要运用button实现标签创建及选择功能,简单易懂可以直接将代码复制到xcode的.m文件中使用.

效果图

屏幕快照 2016-04-16 上午9.49.52.png

//
// ViewController.m
// Sirius_选择标签的创建
//
// Created by Sirius on 16/4/15.
// Copyright © 2016年 Sirius. All rights reserved.
//
#define SCREEN_WIDTH self.view.bounds.size.width
#define SCREEN_HEIGHT self.view.bounds.size.height
#import "ViewController.h"

@interface ViewController ()
{
NSString *STR;
NSMutableArray *btnAll;
NSArray *array ;
}
@property(nonatomic,strong)UITextView *text;

@end

@implementation ViewController

- (void)viewDidLoad {
[super viewDidLoad];

self.view.backgroundColor =[UIColor grayColor];
[self creatUI];

}


-(void)creatUI{
//设置初始值(不设置点击标签时会在TextView中显示一个NULL)
STR = @"";
//要显示的标签数组

array =@[@"尊严这个",@"东西,其实",@"是和欲望",@"成反比的,",@"你想得到",@"一个东西,",@"就会变得",@"低三下四,",@"死皮赖脸,",@"而当你对",@"眼前",@"这个人",@"这个事",@"无动于衷",@"的时候,",@"尊严就会",@"在你心中",@"拔地而起."];

// 保存前一个button的宽以及前一个button距离屏幕边缘的距
CGFloat edge =0;
//设置button 距离父视图的高
CGFloat h =100;


for (int i =0; i< array.count; i++) {
    UIButton *button =[UIButton buttonWithType:UIButtonTypeSystem];
    button.tag =100+i;
    button.backgroundColor =[UIColor grayColor];
    [button addTarget:self action:@selector(selectClick:) forControlEvents:(UIControlEventTouchUpInside)];
    [button setTitleColor:[UIColor whiteColor] forState:(UIControlStateNormal)];
    
    //确定文字的字号
    NSDictionary *attributes =@{NSFontAttributeName:[UIFont systemFontOfSize:12]};
    //计算文字的长度值
    CGFloat length = [array[i] boundingRectWithSize:CGSizeMake(SCREEN_WIDTH, SCREEN_HEIGHT) options:NSStringDrawingUsesLineFragmentOrigin attributes:attributes context:nil].size.width;
    
    //为button赋值
    [button setTitle:array[i] forState:(UIControlStateNormal)];
    
    //设置button的frame
    button.frame =CGRectMake(edge+10, h, length+20, 30);
    
    //当button的位置超出屏幕边缘时换行 320 只是button所在父视图的宽度
    if (edge+10+length +15 >SCREEN_WIDTH) {
        //换行时将左边距设置为10
        edge =0;
        //距离父视图的高度变化
        h=h+button.frame.size.height +10;
        //标签换行后的frame
        button.frame =CGRectMake(edge+10, h, length+15, 30);
        
    }
    
    //获取前一个button的尾部位置位置
    edge = button.frame.size.width +button.frame.origin.x;
    
    [self.view addSubview:button];
    [btnAll addObject:button];
    
    //******设置 数组的第一个button为选中状态
    ((UIButton*)[btnAll objectAtIndex:0]).selected =YES;
}
_text = [[UITextView alloc]initWithFrame:CGRectMake(0, 300, SCREEN_WIDTH, 60)];
[self.view addSubview:_text];


}

//点击事件
- (void)selectClick:(UIButton *)btn{


STR = [NSString stringWithFormat:@"%@%@",STR,array[btn.tag - 100]];
_text.text = STR;

}

@end