ios - oc 如何获得用 Masonry 约束好的宽度？

Question

oc 如何获得用 Masonry 约束好的宽度？
例子：

/// 怎样获取里面约束好的 45 呢？请问！！
    [self.choseCityBtn mas_makeConstraints:^(MASConstraintMaker *make) {
        make.left.equalTo(@(12));
        make.width.equalTo(@(45));
        make.height.equalTo(@(24));
        make.centerY.equalTo(@(navCenterY));
    }];

Answer 1

In View

- (void)layoutSubviews {
    [super layoutSubviews];

    // 获取到约束后的控件frame
}

In controller

- (void)viewDidLayoutSubviews {
    [super viewDidLayoutSubviews];

    // 获取到约束后的控件frame
}

Reference materials: https://github.com/SnapKit/Ma...
Other information: http://elijahdou.github.io/ui...

Answer 2

1. Extract 45 as a variable

2. All constraints loaded through masonry can be passed
   NSArray *installedConstraints = [MASViewConstraint installedConstraintsForView:self.choseCityBtn]

Get.
Then you loop through the array and find the constraint you want

Answer 3

Get it from NSConstraint.

Answer 4

After setting up, force refresh setNeedDisplay and then you can get the attributes after the forced refresh through the frame