AnchorPoint test

ViewController.m

//
//  ViewController.m
//  AnchorPointTest
//
//  Created by gadmyth on 7/10/17.
//  Copyright © 2017 gadmyth. All rights reserved.
//

#import "ViewController.h"

@interface ViewController ()
@property (strong, nonatomic) UITextField *t1;
@property (strong, nonatomic) UITextField *t2;
@property (strong, nonatomic) CALayer *mLayer;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    _t1 = [[UITextField alloc] initWithFrame:CGRectMake(10, 70, 100, 40)];
    _t1.borderStyle = UITextBorderStyleRoundedRect;
    _t1.placeholder = @"请输入0~1内值";
    _t2 = [[UITextField alloc] initWithFrame:CGRectMake(120, 70, 100, 40)];
    _t2.borderStyle = UITextBorderStyleRoundedRect;
    _t2.placeholder = @"请输入0~1内值";
    [self.view addSubview:_t1];
    [self.view addSubview:_t2];
    
    UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(10, 120, 60, 40)];
    [button setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    [button setTitle:@"确定" forState:UIControlStateNormal];
    [button addTarget:self action:@selector(anchorPointChanged:) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:button];
    
    _mLayer = [CALayer layer];
    _mLayer.backgroundColor = [[UIColor alloc] initWithRed:0.7 green:0