背景平铺
ViewController.m
//
// ViewController.m
// 6A04.北京平铺
//
// Created by huan on 16/1/30.
// Copyright © 2016年 huanxi. All rights reserved.
//
#import "ViewController.h"
@interface ViewController ()
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
//添加控制器的背景
self.view.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"textBg.jpg"]];
//0.从bundle的new文件获取文字
//0.1 获取文件路径
NSString *path = [[NSBundle mainBundle] pathForResource:@"news" ofType:nil];
//0.2 读取里面的文字
NSString *news = [NSString stringWithContentsOfFile:path encoding:NSUTF8StringEncoding error:nil];
//1.把文字显示上去 UITextView 显示多行数据，并且可编辑
UITextView *textView = [[UITextView alloc] initWithFrame:self.view.bounds];
//设置文本
textView.text = news;
//设置TextView的背景
#warning 图片有缓存，clear ，iOS8中图片不放在Suporting File下，iOS9没有影响
textView.backgroundColor = [UIColor clearColor];
//设置文字的大小
// textView.font = [UIFont systemFontOfSize:20];
//也可以这样获得字体
textView.font = [UIFont fontWithName:@"Verdana" size:20];
// 当前系统可用的字体
NSLog(@"%@", [UIFont familyNames]);
textView.alpha = 0.5;
[self.view addSubview:textView];
//2.设置文字背景
//2.1 画一个虚线的背景图片
UIImage *dashBgImage = [self dashBgImage];
//2.2 画一个虚线的背景图片平铺(第一种)
// textView.backgroundColor = [UIColor colorWithPatternImage:dashBgImage];
//2.2 创建一个ImageView，添加TextView的第一位置
UIImageView *bgImageView = [[UIImageView alloc] init];
// 背景设置大小的时候，是根据 文字的字数和字体的大小决定
//文字需要的尺寸
CGFloat screenW = [UIScreen mainScreen].bounds.size.width;
CGSize textNeedSize = [news boundingRectWithSize:CGSizeMake(screenW, MAXFLOAT) options:NSStringDrawingUsesLineFragmentOrigin attributes:@{NSFontAttributeName:textView.font} context:nil].size;
bgImageView.frame = CGRectMake(0, 0, textNeedSize.width, textNeedSize.height);
bgImageView.backgroundColor = [UIColor colorWithPatternImage:dashBgImage];
[textView insertSubview:bgImageView atIndex:0];
}
#pragma mark 带虚线的背景图片
-(UIImage *)dashBgImage{
//使用位图上下文
CGFloat bgW = [UIScreen mainScreen].bounds.size.width;
CGFloat bgH = 22;
UIGraphicsBeginImageContextWithOptions(CGSizeMake(bgW, bgH), NO, 0.0);
CGContextRef bitmapContext = UIGraphicsGetCurrentContext();
//画虚线
//计算线的位置
CGFloat lineH = 1;
CGFloat lineY = bgH - lineH;
//设置虚线每段的距离长度
[[UIColor redColor]set];
CGFloat lengths[2] = {10, 5};
CGContextSetLineDash(bitmapContext, 0, lengths, 2);
CGPoint points[2] = {{0, lineY}, {bgW, lineY}};
CGContextAddLines(bitmapContext, points, 2);
CGContextStrokePath(bitmapContext);
//获取背景图片
UIImage *bgImage = UIGraphicsGetImageFromCurrentImageContext();
//结束编辑
UIGraphicsEndImageContext();
return bgImage;
}
@end
