我希望能够向超级视图添加新视图,但使它们彼此之间保持恒定的垂直距离。为此,我尝试以编程方式为每个视图设置约束,但我不知道如何做到这一点。问题是我事先不知道视图的数量或相对位置。
有没有一种方法可以以编程方式为每个视图设置约束,以便无论它们相邻的其他视图如何,自动布局都会保持视图之间的恒定间距?
可能这个简短的代码片段就是您正在寻找的:
NSMutableArray* newVerticalConstraints = [NSMutableArray array];
UIView* firstView = nil;
UIView* secondView = nil;
UIView* superview = <Your container view>;
NSArray* subviews = [superview subviews];
if ([subviews count] > 0) {
firstView = [subviews objectAtIndex:0];
// Add first constraint
[newVerticalConstraints addObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-10-[firstView]" options:0 metrics:nil views:NSDictionaryOfVariableBindings(firstView)]];
for (int i = 1; i < [subviews count]; i++) {
secondView = [subviews objectAtIndex:i];
[newVerticalConstraints addObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:@"V:[firstView]-10-[secondView]" options:0 metrics:nil views:NSDictionaryOfVariableBindings(firstView,secondView)]];
firstView = secondView;
}
// Add last constraint
[newVerticalConstraints addObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:@"V:[firstView]-10-|" options:0 metrics:nil views:NSDictionaryOfVariableBindings(firstView)]];
[superview removeConstraints:self.verticalConstraints];
[superview addConstraints:newVerticalConstraints];
// Save all vertical constraints to be able to remove them
self.verticalConstraints = newVerticalConstraints;
}
本文内容由网友自发贡献,版权归原作者所有,本站不承担相应法律责任。如您发现有涉嫌抄袭侵权的内容,请联系:hwhale#tublm.com(使用前将#替换为@)