我正在嘗試以不同高度垂直居中2個視圖。使用* only *可視格式的中心視圖?
UILabel *view1 = [[UILabel alloc] init];
view1.backgroundColor = [UIColor redColor];
view1.text = @"view1\nline2";
view1.textAlignment = NSTextAlignmentCenter;
view1.numberOfLines = 0;
UILabel *view2 = [[UILabel alloc] init];
view2.backgroundColor = [UIColor greenColor];
view2.text = @"view2\nline2";
view2.textAlignment = NSTextAlignmentCenter;
view2.numberOfLines = 0;
[self.view addSubview:view1];
[self.view addSubview:view2];
NSDictionary *views = @{@"view1": view1, @"view2" : view2};
[self.view setTranslatesAutoresizingMaskIntoConstraints:NO];
for (UIView *view in views.allValues) {
[view setTranslatesAutoresizingMaskIntoConstraints:NO];
}
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-[view1]-[view2(==view1)]-|"
options:NSLayoutFormatAlignAllCenterY
metrics:nil views:views]];
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-(>=20)-[view1(200)]-(>=20)-|"
options:NSLayoutFormatAlignAllCenterY
metrics:nil views:views]];
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-(>=20)-[view2(100)]-(>=20)-|"
options:NSLayoutFormatAlignAllCenterY
metrics:nil views:views]];
這使得兩個中心都垂直對齊,但它們位於超視圖的底部!
我想垂直中心不僅相對於彼此,也在超視圖。
我說像這樣的約束,它的工作原理:
[self.view addConstraint:
[NSLayoutConstraint constraintWithItem:view1
attribute:NSLayoutAttributeCenterY
relatedBy:NSLayoutRelationEqual
toItem:self.view
attribute:NSLayoutAttributeCenterY
multiplier:1
constant:0]];
但我想知道,這是可能實現只用視覺形式?
我使用PureLayout來處理這類事情。 – elkraneo 2014-12-02 20:57:05