_label1= [UILabelnew];
_label1.backgroundColor = [UIColor yellowColor];
_label1.text = @"label,";
_label2= [UILabelnew];
_label2.backgroundColor = [UIColor greenColor];
_label2.text = @"label,";
[_contentView1 addSubview:_label1];
[_contentView1 addSubview:_label2];
// label1: 位于左上角
[_label1 mas_makeConstraints:^(MASConstraintMaker *make) {
make.centerY.equalTo(_contentView1);
make.left.equalTo(_contentView1.mas_left).with.offset(2);
// 40高度
make.height.equalTo(@20);
}];
// label2: 位于右上角
[_label2 mas_makeConstraints:^(MASConstraintMaker *make) {
//左边贴着label1
make.left.equalTo(_label1.mas_right).with.offset(2);
//上边贴着父view
// make.top.equalTo(_contentView1.mas_top).with.offset(5);
make.centerY.equalTo(_contentView1);
//右边的间隔保持大于等于2，注意是lessThanOrEqual
//这里的“lessThanOrEqualTo”放在从左往右的X轴上考虑会更好理解。
//即：label2的右边界的X坐标值“小于等于”containView的右边界的X坐标值。
make.right.lessThanOrEqualTo(_contentView1.mas_right).with.offset(-2);
//只设置高度40
make.height.equalTo(@20);
}];
//设置label1的content hugging 为1000
[_label1 setContentHuggingPriority:UILayoutPriorityRequired
forAxis:UILayoutConstraintAxisHorizontal];
//设置label1的content compression 为1000
[_label1 setContentCompressionResistancePriority:UILayoutPriorityRequired
forAxis:UILayoutConstraintAxisHorizontal];
//设置右边的label2的content hugging 为1000
[_label2 setContentHuggingPriority:UILayoutPriorityRequired
forAxis:UILayoutConstraintAxisHorizontal];
//设置右边的label2的content compression 为250
[_label2 setContentCompressionResistancePriority:UILayoutPriorityDefaultLow
forAxis:UILayoutConstraintAxisHorizontal];
// Content Hugging Priority代表控件拒绝拉伸的优先级。优先级越高，控件会越不容易被拉伸。
// Content Compression Resistance Priority代表控件拒绝压缩内置空间的优先级。优先级越高，控件的内置空间会越不容易被压缩。
