手写控件布局

1. 打开开关

[logoImageView setTranslatesAutoresizingMaskIntoConstraints:NO];

2.开始布局

NSMutableArray *tmpConstraints = [NSMutableArray array];
[tmpConstraints addObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-70-[logoImageView(==70)]" options:0 metrics:nil views:NSDictionaryOfVariableBindings(logoImageView)]];
[tmpConstraints addObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:@"[logoImageView(==70)]" options:0 metrics:nil views:NSDictionaryOfVariableBindings(logoImageView)]];
[tmpConstraints addObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:@"|-40-[forgetPasswordBtn]" options:0 metrics:nil views:NSDictionaryOfVariableBindings(forgetPasswordBtn)]];
[tmpConstraints addObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:@"V:[forgetPasswordBtn]-100-|" options:0 metrics:nil views:NSDictionaryOfVariableBindings(forgetPasswordBtn)]];

[self.view addConstraints:tmpConstraints];

手写控件布局

原文：http://www.cnblogs.com/GJ-ios/p/5483248.html