iOS 代码控制布局缩放

屏幕快照 2019-01-25 下午1.32.16.png 屏幕快照 2019-01-25 下午1.32.25.png

自定义伸缩控件rootview，内部包含4个子view，位于4个角落

layoutSubviews系统方法用于重新布局时调用；

头文件

#import <UIKit/UIKit.h>

@interface RootView : UIView{
    UIView* view1;
    UIView* view2;
    UIView* view3;
    UIView* view4;
}

-(void) createSubViews;

@end

源文件

#import "RootView.h"

@implementation RootView

-(void) createSubViews{
    view1 = [[UIView alloc]init];
    view1.frame = CGRectMake(0, 0, 50, 50);
    view1.backgroundColor = [UIColor greenColor];
    
    view2 = [[UIView alloc]init];
    view2.frame = CGRectMake(self.bounds.size.width - 50, 0, 50, 50);
    view2.backgroundColor = [UIColor yellowColor];
    
    view3 = [[UIView alloc]init];
    view3.frame = CGRectMake(0, self.bounds.size.height - 50, 50, 50);
    view3.backgroundColor = [UIColor redColor];
    
    view4 = [[UIView alloc]init];
    view4.frame = CGRectMake(self.bounds.size.width-50, self.bounds.size.height-50, 50, 50);
    view4.backgroundColor = [UIColor grayColor];
    
    [self addSubview:view1];
    [self addSubview:view2];
    [self addSubview:view3];
    [self addSubview:view4];
}

-(void) layoutSubviews{
    view1.frame = CGRectMake(0, 0, 50, 50);
    view2.frame = CGRectMake(self.bounds.size.width - 50, 0, 50, 50);
    view3.frame = CGRectMake(0, self.bounds.size.height - 50, 50, 50);
    view4.frame = CGRectMake(self.bounds.size.width-50, self.bounds.size.height-50, 50, 50);
}
@end

编写页面布局ViewController

头文件

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController


@end

源文件

#import "ViewController.h"
#import "RootView.h"

@interface ViewController ()

@end

@implementation ViewController

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

-(void) initView{
    RootView* root = [[RootView alloc]init];
    root.frame = CGRectMake(20, 20, 200, 200);
    root.backgroundColor = [UIColor orangeColor];
    [self.view addSubview:root];
    [root createSubViews];
    
    UIButton* btn1 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    btn1.frame = CGRectMake(20, 500, 200, 50);
    [btn1 setTitle:@"放大" forState:UIControlStateNormal];
    [btn1 setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
    btn1.backgroundColor = [UIColor grayColor];
    [self.view addSubview:btn1];
    
    UIButton* btn2 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    btn2.frame = CGRectMake(20, 580, 200, 50);
    [btn2 setTitle:@"缩小" forState:UIControlStateNormal];
    [btn2 setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
    btn2.backgroundColor = [UIColor grayColor];
    [self.view addSubview:btn2];
    
    [btn1 addTarget:self action:@selector(larger) forControlEvents:UIControlEventTouchUpInside];
    [btn2 addTarget:self action:@selector(small) forControlEvents:UIControlEventTouchUpInside];
    root.tag = 101;
}

-(void) larger{
    RootView* root = [self.view viewWithTag:101];
    root.frame = CGRectMake(20, 20, 300, 300);
}

-(void) small{
    RootView* root = [self.view viewWithTag:101];
    root.frame = CGRectMake(20, 20, 200, 200);
}



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


@end