Masonry 动画

比如想做一个最简单的位移动画：

关键点在，改完约束后，调用下面这段代码，父view调用 layoutIfNeeded

[UIView animateWithDuration:0.5 animations:^{

[self.view layoutIfNeeded];

}];

#import "ViewController.h"

#import <Masonry.h>

@interface ViewController ()

@property (nonatomic, strong) UIView *myView;

@end

@implementation ViewController

- (void)viewDidLoad {

[super viewDidLoad];

self.myView = [UIView new];

self.myView.backgroundColor = [UIColor redColor];

[self.view addSubview:self.myView];

[self.myView mas_remakeConstraints:^(MASConstraintMaker *make) {

make.top.mas_equalTo(self.view).offset(100);

make.left.mas_equalTo(self.view).offset(100);

make.width.mas_equalTo(100);

make.height.mas_equalTo(100);

}];

}

- (IBAction)clickButton:(id)sender {

[self.myView mas_remakeConstraints:^(MASConstraintMaker *make) {

make.top.mas_equalTo(self.view).offset(300);

make.left.mas_equalTo(self.view).offset(100);

make.width.mas_equalTo(80);

make.height.mas_equalTo(80);

}];

[UIView animateWithDuration:0.5 animations:^{

[self.view layoutIfNeeded];

}];

}

@end