|-5-[_modeSwitchButton(22)]-5-[_editView]-8-[_inputViewButton(25)]-10-|
这个是 距离左边5 _modeSwitchButton（长度22）距离_editView5 距离_inputViewButton8 （长度25）距离右边10 这样？
V:|[_modeSwitchButton]|  为什么这个有个V 我把V去掉控件就没了
[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@”|-5-[_editView]-8-[_inputViewButton(25)]-10-|”
                                                                     options:0 metrics:nil views:views]];
    }
    
    [self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@”V:|[_inputViewButton]|” options:0 metrics:nil views:views]];
    [self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@”V:|-5-[_editView]-5-|” options:0 metrics:nil views:views]];