iOS: 学习笔记, 用代码驱动自动布局实例

iOS自动布局是设置iOS界面的利器.

本实例展示了如何使用自动布局语言设置水平布局, 垂直布局

1. 创建空白iOS项目

2. 添加一个控制器类, 修改YYAppDelegate.m文件

#import "YYAppDelegate.h"
#import "YYViewController.h"

@implementation YYAppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch.
    self.window.backgroundColor = [UIColor whiteColor];

    self.window.rootViewController = [[YYViewController alloc] initWithNibName:nil bundle:nil];

    [self.window makeKeyAndVisible];
    return YES;
}

3. 修改控制器类

 //
 //  YYViewController.m
 //  UIBasic060701_Button
 //
 //  Created by yao_yu on 14-6-7.
 //  Copyright (c) 2014年 yao_yu. All rights reserved.
 //

 #import "YYViewController.h"

 @interface YYViewController ()

 @property(nonatomic, strong) UIView *viewMoveBlock;

 @end

 @implementation YYViewController

 - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
 {
     self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
     if (self) {
         // Custom initialization
     }
     return self;
 }

 - (void)viewDidLoad
 {
     [super viewDidLoad];

     self.viewMoveBlock = [[UIView alloc] init];
     [self.viewMoveBlock setBackgroundColor:[UIColor blueColor]];
     self.viewMoveBlock.frame = CGRectMake(, , , );
     [self.view addSubview: self.viewMoveBlock];

     UIView *commandPane = [[UIView alloc] initWithFrame:CGRectMake(, , , )];
     [self.view addSubview:commandPane];

     const CGFloat BUTTONSIZE = ;
     UIButton *buttonLeft = [UIButton buttonWithType:UIButtonTypeRoundedRect];
     [buttonLeft setTitle:@"左移" forState:UIControlStateNormal];
     buttonLeft.frame = CGRectMake(, , BUTTONSIZE, BUTTONSIZE);
     [commandPane addSubview: buttonLeft];
     [buttonLeft addTarget:self action:@selector(moveLeft) forControlEvents:UIControlEventTouchUpInside];

     UIButton *buttonRight = [UIButton buttonWithType:UIButtonTypeRoundedRect];
     [buttonRight setTitle:@"右移" forState:UIControlStateNormal];
     buttonRight.frame = CGRectMake(BUTTONSIZE, , BUTTONSIZE, BUTTONSIZE);
     [commandPane addSubview: buttonRight];
     [buttonRight addTarget:self action:@selector(moveRight) forControlEvents:UIControlEventTouchUpInside];

     UIButton *buttonUp = [UIButton buttonWithType:UIButtonTypeRoundedRect];
     [buttonUp setTitle:@"上移" forState:UIControlStateNormal];
     buttonUp.frame = CGRectMake(BUTTONSIZE*, , BUTTONSIZE, BUTTONSIZE);
     [commandPane addSubview: buttonUp];
     [buttonUp addTarget:self action:@selector(moveUp) forControlEvents:UIControlEventTouchUpInside];

     UIButton *buttonDown = [UIButton buttonWithType:UIButtonTypeRoundedRect];
     [buttonDown setTitle:@"下移" forState:UIControlStateNormal];
     buttonDown.frame = CGRectMake(BUTTONSIZE*, , BUTTONSIZE, BUTTONSIZE);
     [commandPane addSubview: buttonDown];
     [buttonDown addTarget:self action:@selector(moveDown) forControlEvents:UIControlEventTouchUpInside];

     UIButton *buttonZoomOut = [UIButton buttonWithType:UIButtonTypeRoundedRect];
     [buttonZoomOut setTitle:@"放大" forState:UIControlStateNormal];
     buttonZoomOut.frame = CGRectMake(BUTTONSIZE*, , BUTTONSIZE, BUTTONSIZE);
     [commandPane addSubview: buttonZoomOut];
     [buttonZoomOut addTarget:self action:@selector(zoomOut) forControlEvents:UIControlEventTouchUpInside];

     UIButton *buttonZoomIn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
     [buttonZoomIn setTitle:@"缩小" forState:UIControlStateNormal];
     buttonZoomIn.frame = CGRectMake(BUTTONSIZE*, , BUTTONSIZE, BUTTONSIZE);
     [commandPane addSubview: buttonZoomIn];
     [buttonZoomIn addTarget:self action:@selector(zoomIn) forControlEvents:UIControlEventTouchUpInside];

     [commandPane setTranslatesAutoresizingMaskIntoConstraints:NO];
     [self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"[commandPane(260)]" options: metrics: views:NSDictionaryOfVariableBindings(commandPane)]];
     [self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-[commandPane(50)]" options: metrics: views:NSDictionaryOfVariableBindings(commandPane)]];
     [self.view addConstraint:[NSLayoutConstraint constraintWithItem:commandPane attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeCenterX multiplier:1.0f constant:0.0f]];

     NSDictionary *metrics = [NSDictionary dictionaryWithObjectsAndKeys:@, @"SIZE", nil];
     NSDictionary *contraitsView = NSDictionaryOfVariableBindings(buttonLeft, buttonRight, buttonUp, buttonDown, buttonZoomOut, buttonZoomIn);
     for (NSString *buttonKey in contraitsView ) {
         [contraitsView[buttonKey] setTranslatesAutoresizingMaskIntoConstraints:NO];
         [commandPane addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:[NSString stringWithFormat:@"V:|[%@(SIZE)]", buttonKey] options: metrics:metrics views:contraitsView]];
     }
     [commandPane addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[buttonLeft(SIZE)][buttonRight(SIZE)][buttonUp(SIZE)][buttonDown(SIZE)]-(>=0)-[buttonZoomOut(SIZE)][buttonZoomIn(SIZE)]|" options: metrics:metrics views: contraitsView]];
 }

 -(void)moveLeft
 {
     [self moveX: - Y:];
 }

 -(void)moveRight
 {
     [self moveX:  Y:];
 }

 -(void)moveUp
 {
     [self moveX:  Y:-];
 }

 -(void)moveDown
 {
     [self moveX:  Y:];
 }

 -(void)zoomOut
 {
     CGRect rect = self.viewMoveBlock.frame;

     rect.origin.x -= ;
     rect.origin.y -= ;
     rect.size.width += ;
     rect.size.height += ;

     [UIView beginAnimations:nil context:nil];
     [UIView setAnimationDuration:1.0];

     self.viewMoveBlock.frame = rect;

     [UIView commitAnimations];
 }

 -(void)zoomIn
 {
     CGRect rect = self.viewMoveBlock.frame;

     rect.origin.x += ;
     rect.origin.y += ;
     rect.size.width -= ;
     rect.size.height -= ;

     [UIView beginAnimations:nil context:nil];
     [UIView setAnimationDuration:1.0];

     self.viewMoveBlock.frame = rect;

     [UIView commitAnimations];
 }

 -(void)moveX: (int)x Y:(int)y
 {
     CGPoint p = self.viewMoveBlock.center;

     p.x += x;
     p.y += y;

     [UIView beginAnimations:nil context:nil];
     [UIView setAnimationDuration:1.0];

     self.viewMoveBlock.center = p;

     [UIView commitAnimations];
 }

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

 /*
 #pragma mark - Navigation

 // In a storyboard-based application, you will often want to do a little preparation before navigation
 - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
 {
     // Get the new view controller using [segue destinationViewController].
     // Pass the selected object to the new view controller.
 }
 */

 @end

4. 运行