ios VFL 简单例子 ParseSWTableViewCell 想要修改 上下按钮的边距

摘要: ios VFL 简单例子 ParseSWTableViewCell 想要修改 上下按钮的边距

今天 在使用 ParseSWTableViewCell 想要修改 上下按钮的边距

if (!precedingView)
{
// First button; pin it to the left edge.
[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[button]"
options:0L
metrics:nil
views:NSDictionaryOfVariableBindings(button)]];
//增加第一个按钮上下位置
[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-5-[button]-5-|"
options:0L
metrics:nil
views:NSDictionaryOfVariableBindings(button)]];
}
else
{
// Subsequent button; pin it to the right edge of the preceding one, with equal width.
[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:[precedingView][button(==precedingView)]"
options:NSLayoutFormatAlignAllTop
metrics:nil
views:NSDictionaryOfVariableBindings(precedingView, button)]];
//增加 上下位置一致的约束
[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:[precedingView][button(==precedingView)]"
options:NSLayoutFormatAlignAllBottom
metrics:nil
views:NSDictionaryOfVariableBindings(precedingView, button)]];

借鉴 黑马 VFL代码

//
//  ViewController.m
//  06-VFL添加约束
//
//  Created by apple on 14/11/4.
//  Copyright (c) 2014年 heima. All rights reserved.
//

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
[super viewDidLoad];
// 1.添加两个控件到父控件上
// 1.1添加蓝色View
UIView *blueView = [[UIView alloc] init];
blueView.backgroundColor = [UIColor blueColor];
[self.view addSubview:blueView];

// 1.1添加红色View
UIView *redView = [[UIView alloc] init];
redView.backgroundColor = [UIColor redColor];
[self.view addSubview:redView];

// 2.禁用auturezing
blueView.translatesAutoresizingMaskIntoConstraints = NO;
redView.translatesAutoresizingMaskIntoConstraints = NO;

// 3.添加约束
/*
lFormat : VFL语句
options: 对齐方式
metrics: VFL语句中用到的变量值
views: VFL语句中用到的控件
*/
// 设置蓝色View距离左边和右边有20的的间距  X 和 宽度
//    NSArray *blueViewH = [NSLayoutConstraint constraintsWithVisualFormat:@"H:|-20-[blueView]-20-|" options:0 metrics:nil views:@{@"blueView" : blueView}];
int margin = 20;
NSArray *blueViewH = [NSLayoutConstraint constraintsWithVisualFormat:@"H:|-margin-[blueView]-margin-|" options:0 metrics:@{@"margin": @(margin)} views:@{@"blueView" : blueView}];
[self.view addConstraints:blueViewH];

// 设置蓝色View距离顶部有20的间距, 并且高度等于50   Y 和高度
// 设置红色View距离蓝色底部有20的间距, 并且红色View的高度等于蓝色View的高度 Y 和高度
// 并且设置红色和蓝色右对齐
NSArray *blueViewV = [NSLayoutConstraint constraintsWithVisualFormat:@"V:|-20-[blueView(50)]-20-[redView(==blueView)]" options:NSLayoutFormatAlignAllRight metrics:nil views:@{@"blueView" : blueView, @"redView": redView}];
[self.view addConstraints:blueViewV];

// 注意: 在VFL语句中, 是不支持乘除法
//    NSArray *redVeiwH = [NSLayoutConstraint constraintsWithVisualFormat:@"H:[redView(==blueView )]" options:0 metrics:nil views:@{@"blueView" : blueView, @"redView": redView}];
//    [self.view addConstraints:redVeiwH];

NSLayoutConstraint *redVeiwW = [NSLayoutConstraint constraintWithItem:redView attribute:NSLayoutAttributeWidth relatedBy:NSLayoutRelationEqual toItem:blueView attribute:NSLayoutAttributeWidth multiplier:0.5 constant:0];
[self.view addConstraint:redVeiwW];
}

@end