iOS开发从入门到精通--手动布局子视图

手动布局子视图；
下面先看下效果图，我们今天要实现的效果：

这里我们默认用storyboard启动：
首先我们要在白色的屏幕上面创建一个父视图SuperView（蓝色的背景）,在父视图里面创建四个小视图（橘黄色的背景）
下面看代码，
在SuperView.h文件里面：

#import <UIKit/UIKit.h>

@interface SuperView : UIView{

    UIView * _view01;
    UIView * _view02;
    UIView * _view03;
    UIView * _view04;

}

//声明创建视图函数
-(void) createSubViews;

@end

在SuperView.m文件里面：

#import "SuperView.h"

@interface SuperView ()

@end

@implementation SuperView

-(void) createSubViews{

    //左上角视图
    _view01 = [[UIView alloc] init];
    _view01.frame=CGRectMake(0, 0, 40, 40);

    //右上角视图
    _view02 = [[UIView alloc] init];
    _view02.frame=CGRectMake(self.bounds.size.width-40, 0, 40, 40);

    //右下角视图
    _view03 = [[UIView alloc] init];
    _view03.frame=CGRectMake(self.bounds.size.width-40, self.bounds.size.height-40, 40, 40);

    //左下角视图
    _view04 = [[UIView alloc] init];
    _view04.frame=CGRectMake(0, self.bounds.size.height-40, 40, 40);

    _view01.backgroundColor=[UIColor orangeColor];
    _view02.backgroundColor=[UIColor orangeColor];
    _view03.backgroundColor=[UIColor orangeColor];
    _view04.backgroundColor=[UIColor orangeColor];

    [self addSubview:_view01];
    [self addSubview:_view02];
    [self addSubview:_view03];
    [self addSubview:_view04];

}

//当需要重新布局时调用此函数
//通过此函数重新设定子视图的位置
//手动调整子视图的位置
-(void)layoutSubviews{

    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:1];

    _view01.frame=CGRectMake(0, 0, 40, 40);
    _view02.frame=CGRectMake(self.bounds.size.width-40, 0, 40, 40);
    _view03.frame=CGRectMake(self.bounds.size.width-40, self.bounds.size.height-40, 40, 40);
    _view04.frame=CGRectMake(0, self.bounds.size.height-40, 40, 40);

    [UIView commitAnimations];

}


@end

在 ViewController.m文件里面：

#import "ViewController.h"
#import "SuperView.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    //创建一个父视图
    SuperView * sView = [[SuperView alloc]init];
    sView.frame = CGRectMake(20, 20, 180, 280);

    //父视图调用函数创建四个小视图
    [sView createSubViews];

    sView.backgroundColor = [UIColor blueColor];
    [self.view addSubview:sView];

    UIButton * btn01 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    btn01.frame = CGRectMake(240, 480, 80, 40);
    [btn01 setTitle:@"放大" forState:UIControlStateNormal];
    [btn01 addTarget:self action:@selector(pressLarge) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:btn01];

    UIButton * btn02 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    btn02.frame = CGRectMake(240, 520, 80, 40);
    [btn02 setTitle:@"缩小" forState:UIControlStateNormal];
    [btn02 addTarget:self action:@selector(pressSmall) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:btn02];

    sView.tag = 101;


}

//放大父视图
-(void) pressLarge{
    SuperView * sView = (SuperView*)[self.view viewWithTag:101];
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:1];
    sView.frame=CGRectMake(20, 20, 280, 400);
    [UIView commitAnimations];

}

//缩小父视图

-(void) pressSmall{
    SuperView * sView = (SuperView*)[self.view viewWithTag:101];
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:1];
    sView.frame=CGRectMake(20, 20, 180, 280);
    [UIView commitAnimations];
}


- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

以上代码书写完毕，就达到了上面视图的效果，代码没有注释太多，因为之前的代码里面注释的很详细，现在不一一注释，具体可以看我之前的文章，谢谢！