UIViewAutoresizing只能控制父子视图之间的布局
首先父视图要允许子视图自动伴随父视图变化而变化
然后子视图自己设置怎么伴随变化
//父视图设置父子视图自适应/停靠模式
_redView.autoresizesSubviews = YES;//允许子视图伴随父视图自动变化
//子视图设置子视图的自适应模式
blueView.autoresizingMask
autolayout iOS6的时候出来的
sizeclass iOS8的时候出来的
github
一.自动布局(多屏适配)
1.为什么使用自动布局
iphone手机的分辨率越来越多,有320*480, 640*960, 640*1136, 750*1334, 1080*1920
使用代码控制frame坐标和大小的化,会花费大量时间精力.
为了解决适配问题,苹果推出了自动布局
2.自动布局原理
通过给视图添加约束的方式,使视图在任何屏幕上都可以正常显示
autolayout 用 constraints(约束) 来控制 控件的大小和位置
auto layout 加约束条件 问题1:要么加少了 起不到作用，2.加多了产生了冲突 有可能崩溃
3.如何给视图添加约束
Xcode—>Editor—>Pin
4.有哪些约束
1).Width //设置视图固定宽度
2).Height //设置视图固定高度
3).Horizontal Spacing //同级视图之间的横向间距
4).Vertical Spacing //同级视图之间的纵向间距
5).Leading Space to SuperView //与父视图的左间距
6).Trailing Space to SuperView //与父视图的右间距
7).Top Space to SuperView //与父视图的上间距
8).Botton Space to SuperView //与父视图的下间距
9).Widths Equally //设置同级视图宽度比例
10).Height Equally //设置同级视图高度比例
NSLayoutConstraint *constraint =
[NSLayoutConstraint
constraintWithItem:self.contentView
attribute:NSLayoutAttributeWidth
relatedBy:NSLayoutRelationEqual
toItem:nil
attribute:0
multiplier:1.0
constant:1000];
NSLayoutConstraint *constraint2 =
[NSLayoutConstraint
constraintWithItem:self.contentView
attribute:NSLayoutAttributeHeight
relatedBy:NSLayoutRelationEqual
toItem:nil
attribute:0
multiplier:1.0
constant:200];
[self.contentView addConstraint:constraint];
[self.contentView addConstraint:constraint2];
NSDictionary *views = NSDictionaryOfVariableBindings(_contentView);
// NSDictionary *dict = @{@"_contentView": _contentView};
NSArray *constraints =
[NSLayoutConstraint constraintsWithVisualFormat:@"H:[_contentView(1000)]" options:0 metrics:nil views:views];
NSArray *constraints2 = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[_contentView(200)]" options:0 metrics:nil views:views];
[_contentView addConstraints:constraints];
[_contentView addConstraints:constraints2];
===================================================
VFL 语言添加约束
UIView *redView = [[UIView alloc] initWithFrame:CGRectZero];
redView.backgroundColor = [UIColor redColor];
// 通常都设置成NO
redView.translatesAutoresizingMaskIntoConstraints = NO;
[self.view addSubview:redView];
UIView *blueView = [[UIView alloc] initWithFrame:CGRectZero];
blueView.backgroundColor = [UIColor blueColor];
// 通常都设置成NO
blueView.translatesAutoresizingMaskIntoConstraints = NO;
[self.view addSubview:blueView];
NSDictionary *views = NSDictionaryOfVariableBindings(redView, blueView);
//NSDictionary *dict = @{@“redView”:redView,@“blueView”: blueView};
NSArray *constraints =
[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-100-[redView(100)]" options:0 metrics:nil views:views];
[self.view addConstraints:constraints];
NSArray *constraints2 =
[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-100-[redView(50)]" options:0 metrics:nil views:views];
[self.view addConstraints:constraints2];
NSArray *constraints3 =
[NSLayoutConstraint constraintsWithVisualFormat:@"H:[redView]-50-[blueView(==redView)]" options:0 metrics:nil views:views];
[self.view addConstraints:constraints3];
NSArray *constraints4 =
[NSLayoutConstraint constraintsWithVisualFormat:@"V:[redView]-50-[blueView(==redView)]" options:0 metrics:nil views:views];
[self.view addConstraints:constraints4];
5.用代码做自动布局
使用第三方Masonry库
[topView mas_makeConstraints:^(MASConstraintMaker *make) {
make.top.equalTo(self.view.mas_top).with.offset(0); //topView上边距与self.view上边距为0
make.left.equalTo(self.view.mas_left).with.offset(0); //topView左边距与self.view左边距为0
make.right.equalTo(self.view.mas_right).with.offset(0); //topView右边距与self.view右边距为0
make.height.equalTo(@64); //topView宽度固定为64个像素
}];
[tableView mas_makeConstraints:^(MASConstraintMaker *make) {
make.top.equalTo(topView.mas_bottom).with.offset(0); //tableView上边距与self.view下边距为0
make.bottom.equalTo(bottomView.mas_top).with.offset(0); //tableView下边距与self.view上边距为0
make.left.equalTo(self.view.mas_left).with.offset(0); //tableView左边距与self.view左边距为0
make.right.equalTo(self.view.mas_right).with.offset(0); //tableView右边距与self.view右边距为0
}];
//从下往上,从右往左,都是倒推,是负数.
UIButton *topButton = [UIButton buttonWithType:UIButtonTypeSystem];
topButton.backgroundColor = [UIColor grayColor];
[topView addSubview:topButton];
[topButton mas_makeConstraints:^(MASConstraintMaker *make) {
make.top.equalTo(topView.mas_top).with.offset(20);
//从下往上,从右往左,都是倒推,是负数.
make.bottom.equalTo(topView.mas_bottom).with.offset(-5);
make.right.equalTo(topView.mas_right).with.offset(-20);
make.width.equalTo(@100);
}];
[table mas_makeConstraints:^(MASConstraintMaker *make) {
make.left.equalTo(self.view.mas_left).with.offset(0);
make.right.equalTo(self.view.mas_right).with.offset(0);
//table的上边距和topView的下边距为0
make.top.equalTo(topView.mas_bottom).with.offset(0);
//table的下边距和bottomView的上边距为0
make.bottom.equalTo(bottomView.mas_top).with.offset(0);
}];