#import<UIKit/UIKit.h>
@interface ViewController : UIViewController
@property (nonatomic, strong) UIButton *leftButton;
@property (nonatomic, strong) UIButton *rightButton;
@property (nonatomic, strong) UITextField *textfield;
@end
#import "ViewController.h"
@interface ViewController ()
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
UIView *superview = self.view;
/*1. Create leftButton and add to our view*/
//创建左边的按钮并且添加到视图上
self.leftButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
//自动调整按钮的约束
self.leftButton.translatesAutoresizingMaskIntoConstraints = NO;
[self.leftButton setTitle:@"LeftButton" forState:UIControlStateNormal];
[self.view addSubview:self.leftButton];
/* 2. Constraint to position LeftButton's X*/
//控制左边按钮的 x位置 LayoutConstraint 布局约束
NSLayoutConstraint *leftButtonXConstraint = [NSLayoutConstraint constraintWithItem:self.leftButton attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationGreaterThanOrEqual toItem:superview attribute: NSLayoutAttributeCenterX multiplier:1.0 constant:-60.0f];
/* 3. Constraint to position LeftButton's Y*/
//控制左边按钮的 y位置 LayoutConstraint 布局约束
NSLayoutConstraint *leftButtonYConstraint = [NSLayoutConstraint constraintWithItem:self.leftButton attribute:NSLayoutAttributeCenterY
relatedBy:NSLayoutRelationEqual toItem:superview attribute:NSLayoutAttributeCenterY multiplier:1.0f constant:0.0f];
/* 4. Add the constraints to button's superview*/
//添加按钮的父视图的限制
[superview addConstraints:@[leftButtonXConstraint,leftButtonYConstraint]];
/*5. Create rightButton and add to our view*/
//创建右边的按钮并且添加到视图上
self.rightButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
self.rightButton.translatesAutoresizingMaskIntoConstraints = NO;
[self.rightButton setTitle:@"RightButton" forState:UIControlStateNormal];
[self.view addSubview:self.rightButton];
/*6. Constraint to position RightButton's X*/
//控制右边按钮的 x位置 LayoutConstraint 布局约束
NSLayoutConstraint *rightButtonXConstraint =[NSLayoutConstraint constraintWithItem:self.rightButton attribute:NSLayoutAttributeCenterX
relatedBy:NSLayoutRelationGreaterThanOrEqual toItem:superview attribute: NSLayoutAttributeCenterX multiplier:1.0 constant:60.0f];
/*7. Constraint to position RightButton's Y*/
//控制右边按钮的 y位置 LayoutConstraint 布局约束
rightButtonXConstraint.priority =UILayoutPriorityDefaultHigh;
NSLayoutConstraint *centerYMyConstraint = [NSLayoutConstraint constraintWithItem:self.rightButton attribute:NSLayoutAttributeCenterY
relatedBy:NSLayoutRelationGreaterThanOrEqual toItem:superview attribute:NSLayoutAttributeCenterY multiplier:1.0f constant:0.0f];
[superview addConstraints:@[centerYMyConstraint,rightButtonXConstraint]];
//8. Add Text field
//添加文本框
self.textfield = [[UITextField alloc]initWithFrame:CGRectMake(0, 100, 100, 30)];
self.textfield.borderStyle =1;
self.textfield.translatesAutoresizingMaskIntoConstraints = NO;
[self.view addSubview:self.textfield];
//9. Text field Constraints
//文本字段的约束 顶部
NSLayoutConstraint *textFieldTopConstraint = [NSLayoutConstraint constraintWithItem:self.textfield attribute:NSLayoutAttributeTop
relatedBy:NSLayoutRelationGreaterThanOrEqual toItem:superview attribute:NSLayoutAttributeTop multiplier:1.0 constant:60.0f];
//文本字段的约束 底部
NSLayoutConstraint *textFieldBottomConstraint = [NSLayoutConstraint
constraintWithItem:self.textfield attribute:NSLayoutAttributeTop
relatedBy:NSLayoutRelationGreaterThanOrEqual toItem:self.rightButton
attribute:NSLayoutAttributeTop multiplier:0.8 constant:-60.0f];
//文本字段的约束 左部
NSLayoutConstraint *textFieldLeftConstraint = [NSLayoutConstraint
constraintWithItem:self.textfield attribute:NSLayoutAttributeLeft
relatedBy:NSLayoutRelationEqual toItem:superview attribute:NSLayoutAttributeLeft multiplier:1.0 constant:30.0f];
//文本字段的约束 右部
NSLayoutConstraint *textFieldRightConstraint = [NSLayoutConstraint
constraintWithItem:self.textfield attribute:NSLayoutAttributeRight
relatedBy:NSLayoutRelationEqual toItem:superview attribute:
NSLayoutAttributeRight multiplier:1.0 constant:-30.0f];
[superview addConstraints:@[textFieldBottomConstraint ,textFieldLeftConstraint, textFieldRightConstraint,textFieldTopConstraint]];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end
