你是否已经看够iOS里默认给出的那些方方正正的块状和规规矩矩的陈列？
本篇给出一种随机三角形平铺布局的算法设计和实现。这种布局在规矩与随机之间做了折中，使其看上去有新鲜感又不会很乱。
本次实现重点在于布局算法的设计和实现，可以改变颜色或者添加图片。
最新源代码下载地址：https://github.com/duzixi/Varied-Layouts（持续维护，欢迎互粉）
博文首发地址：http://blog.csdn.net/duzixi
布局生成效果如下：
核心算法设计以及代码实现如下：
//
// TriangleViewController.m
// TriangleLayout
//
// Created by 杜子兮(duzixi) on 14-8-24.
// Copyright (c) 2014年 lanou3g.com All rights reserved.
//
#import "TriangleViewController.h"
#import "Triangle.h"
#import <QuartzCore/QuartzCore.h>
#define PADDING 10
#define SIZE 100
#define COL (self.view.frame.size.width / SIZE)
#define ROW (self.view.frame.size.height / SIZE)
@interface TriangleViewController ()
@end
@implementation TriangleViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
_randomPoints = [NSMutableArray array];
_triangles = [NSMutableArray array];
int oy = - SIZE / 2;
for (int i = 0; i < ROW + 1; i++) {
for (int j = 0; j < COL; j++) {
int ox = (i % 2 == 1) ? j * SIZE : j * SIZE - 0.5 * SIZE;
ox -= SIZE / 4;
// step 1:画格子
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(ox, i * SIZE + oy, SIZE, SIZE)];
if ((j + i ) % 2 == 0) {
view.backgroundColor = [UIColor grayColor];
}
// [self.view addSubview:view];
// step 2:在格子中产生随机点
int x = arc4random() % (SIZE - PADDING * 2) + view.frame.origin.x + PADDING;
int y = arc4random() % (SIZE - PADDING * 2) + view.frame.origin.y + PADDING;
CGPoint p = CGPointMake(x, y);
NSValue *v = [NSValue valueWithCGPoint:p];
[_randomPoints addObject:v];
UIView *pView = [[UIView alloc] initWithFrame:CGRectMake(p.x, p.y, 2, 2)];
pView.backgroundColor = [UIColor blueColor];
// [self.view addSubview:pView];
UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(p.x, p.y, 50, 20)];
label.text = [NSString stringWithFormat:@"%lu",(unsigned long)[_randomPoints count]];
// [self.view addSubview:label];
}
}
int k = 0;
for (int i = 0; i < ROW; i++) {
NSLog(@"-----------------");
for (int j = 0; j < COL - 1; j++) {
// step 3: 俺三角形将点归类
k = i * COL + j + i;
Triangle *t = [[Triangle alloc] init];
t.p1 = [_randomPoints[k] CGPointValue];
t.p2 = [_randomPoints[k + 1] CGPointValue];
int col = i % 2 == 0 ? COL : COL + 1;
t.p3 = [_randomPoints[k + 1 + col] CGPointValue];
NSLog(@"%d %d %d", k , k + 1, k + 1 + col);
[_triangles addObject:t];
// step 4: 生成三角形所在的矩形区域
int minX = t.p1.x < t.p2.x ? t.p1.x : t.p2.x;
minX = minX < t.p3.x ? minX : t.p3.x;
int minY = t.p1.y < t.p2.y ? t.p1.y : t.p2.y;
minY = minY < t.p3.y ? minY : t.p3.y;
int maxX = t.p1.x > t.p2.x ? t.p1.x : t.p2.x;
maxX = maxX > t.p3.x ? maxX : t.p3.x;
int maxY = t.p1.y > t.p2.y ? t.p1.y : t.p2.y;
maxY = maxY > t.p3.y ? maxY : t.p3.y;
k++;
UIImageView *view = [[UIImageView alloc] initWithFrame:CGRectMake(minX, minY, maxX - minX, maxY - minY)];
view.backgroundColor = [UIColor orangeColor];
// step 5: 根据三角形生成蒙板
UIBezierPath *path = [UIBezierPath bezierPath];
[path moveToPoint:CGPointMake(t.p1.x - minX, t.p1.y - minY)];
[path addLineToPoint:CGPointMake(t.p2.x - minX, t.p2.y - minY)];
[path addLineToPoint:CGPointMake(t.p3.x - minX, t.p3.y - minY)];
[path closePath];
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.path = [path CGPath];
view.layer.mask = maskLayer;
[self.view addSubview:view];
}
}
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end
// // Triangle.h // TriangleLayout // // Created by 杜子兮(duzixi) on 14-8-24. // Copyright (c) 2014年 lanou3g.com All rights reserved. // #import <Foundation/Foundation.h> @interface Triangle : NSObject @property (nonatomic, assign) CGPoint p1; @property (nonatomic, assign) CGPoint p2; @property (nonatomic, assign) CGPoint p3; @end
为了让大家看清布局过程，代码中保留了一些中间过程（注释掉了）。
打开注释即可看到格子，随机点等内容。
下一次的目标是将其改写成UICollectionView的Layout，请大家敬请期待