iOS：Autolayout在iPhone中没有显示正确的大小

Question

我正在创建一个应用程序，我需要在底部显示两个名为登录和登录的按钮。 我已经使用了Autolayout，因为我需要支持所有的iPhone设备。 它一直工作到iPhone 5S并显示正确。但是在iPhone 6注册按钮没有扩展其宽度。 我做错了什么，但不知道在哪里。 以下是我的代码。

附件也是截图。

NSDictionary *viewsDictionary = @{@"loginButton":self.loginButton};

//Define the LoginButton Size

NSArray *constraint_H = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[loginButton(52)]" options:0 metrics:nil views:viewsDictionary];
NSArray *constraint_V = [NSLayoutConstraint constraintsWithVisualFormat:@"H:[loginButton(160)]" options:0 metrics:nil views:viewsDictionary];

[self.loginButton addConstraints:constraint_H];
[self.loginButton addConstraints:constraint_V];

//Define the LoginView Postion

NSArray *constraint_POS_V = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[loginButton]-0-|" options:0 metrics:nil views:viewsDictionary];
NSArray *constraint_POS_H = [NSLayoutConstraint constraintsWithVisualFormat:@"H:|-0-[loginButton]" options:0 metrics:nil views:viewsDictionary];

[self.view addConstraints:constraint_POS_V];
[self.view addConstraints:constraint_POS_H];

//Define the SignInButton Size

NSDictionary *yellowDictionary = @{@"signInButton":self.signInButton};

NSArray *yellow_constraint_H = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[signInButton(52)]" options:0 metrics:nil views:yellowDictionary];
NSArray *yellow_constraint_V = [NSLayoutConstraint constraintsWithVisualFormat:@"H:[signInButton(160)]" options:0 metrics:nil views:yellowDictionary];

[self.signInButton addConstraints:yellow_constraint_H];
[self.signInButton addConstraints:yellow_constraint_V];


//Define the SignInView Postion

NSArray *yellowconstraint_POS_V = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[signInButton]-0-|" options:0 metrics:nil views:yellowDictionary];
NSArray *yellowconstraint_POS_H = [NSLayoutConstraint constraintsWithVisualFormat:@"H:|-161-[signInButton]" options:0 metrics:nil views:yellowDictionary];

[self.view addConstraints:yellowconstraint_POS_V];
[self.view addConstraints:yellowconstraint_POS_H];

Answer 1

你有固定的登录按钮和注册按钮大小为160。 这是唯一的问题。

您需要计算屏幕宽度并按顺序给出按钮的宽度约束。

下面的代码将解决您的问题。

CGSize screenSize = [UIScreen mainScreen].bounds.size;

NSArray *constraint_H = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[loginButton(52)]" options:0 metrics:nil views:viewsDictionary];
NSArray *constraint_V = [NSLayoutConstraint constraintsWithVisualFormat:[NSString stringWithFormat:@"H:[loginButton(%.f)]",screenSize.width/2] options:0 metrics:nil views:viewsDictionary];

[self.loginButton addConstraints:constraint_H];
[self.loginButton addConstraints:constraint_V];

//Define the LoginView Postion

NSArray *constraint_POS_V = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[loginButton]-0-|" options:0 metrics:nil views:viewsDictionary];
NSArray *constraint_POS_H = [NSLayoutConstraint constraintsWithVisualFormat:@"H:|-0-[loginButton]" options:0 metrics:nil views:viewsDictionary];

[self.view addConstraints:constraint_POS_V];
[self.view addConstraints:constraint_POS_H];

//Define the SignInButton Size

NSDictionary *yellowDictionary = @{@"signInButton":self.signInButton};

NSArray *yellow_constraint_H = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[signInButton(52)]" options:0 metrics:nil views:yellowDictionary];
NSArray *yellow_constraint_V = [NSLayoutConstraint constraintsWithVisualFormat:[NSString stringWithFormat:@"H:[signInButton(%.f)]",screenSize.width/2]  options:0 metrics:nil views:yellowDictionary];

[self.signInButton addConstraints:yellow_constraint_H];
[self.signInButton addConstraints:yellow_constraint_V];


//Define the SignInView Postion

NSArray *yellowconstraint_POS_V = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[signInButton]-0-|" options:0 metrics:nil views:yellowDictionary];
NSArray *yellowconstraint_POS_H = [NSLayoutConstraint constraintsWithVisualFormat:[NSString stringWithFormat:@"H:|-%f-[signInButton]",(screenSize.width/2)+1] options:0 metrics:nil views:yellowDictionary];

[self.view addConstraints:yellowconstraint_POS_V];
[self.view addConstraints:yellowconstraint_POS_H];