Masonry~(转)

UIEdgeInsets padding = UIEdgeInsetsMake(10, 10, 10, 10);

[view1 mas_makeConstraints:^(MASConstraintMaker *make) { make.top.equalTo(superview.mas_top).with.offset(padding.top); //with is an optional semantic filler
 make.left.equalTo(superview.mas_left).with.offset(padding.left); make.bottom.equalTo(superview.mas_bottom).with.offset(-padding.bottom); make.right.equalTo(superview.mas_right).with.offset(-padding.right); }];

[view1 mas_makeConstraints:^(MASConstraintMaker *make) { make.edges.equalTo(superview).with.insets(padding); }];

make.left.greaterThanOrEqualTo(label); make.left.greaterThanOrEqualTo(label.mas_left);

make.width.greaterThanOrEqualTo(@200); make.width.lessThanOrEqualTo(@400)

make.left.lessThanOrEqualTo(@10)

make.top.mas_equalTo(42); make.height.mas_equalTo(20); make.size.mas_equalTo(CGSizeMake(50, 100)); make.edges.mas_equalTo(UIEdgeInsetsMake(10, 0, 10, 0)); make.left.mas_equalTo(view).mas_offset(UIEdgeInsetsMake(10, 0, 10, 0));

make.height.equalTo(@[view1.mas_height, view2.mas_height]); make.height.equalTo(@[view1, view2]); make.left.equalTo(@[view1, @100, view3.right]);

Masonry also gives you a few convenience methods which create multiple constraints at the same time. These are called MASCompositeConstraints edges // make top, left, bottom, right equal view2
make.edges.equalTo(view2); // make top = superview.top + 5, left = superview.left + 10, // bottom = superview.bottom - 15, right = superview.right - 20
make.edges.equalTo(superview).insets(UIEdgeInsetsMake(5, 10, 15, 20)) size // make width and height greater than or equal to titleLabel
make.size.greaterThanOrEqualTo(titleLabel) // make width = superview.width + 100, height = superview.height - 50
make.size.equalTo(superview).sizeOffset(CGSizeMake(100, -50)) center // make centerX and centerY = button1
make.center.equalTo(button1) // make centerX = superview.centerX - 5, centerY = superview.centerY + 10
make.center.equalTo(superview).centerOffset(CGPointMake(-5, 10)) You can chain view attributes for increased readability: // All edges but the top should equal those of the superview
make.left.right.and.bottom.equalTo(superview); make.top.equalTo(otherView);

make.left.greaterThanOrEqualTo(label.mas_left).with.priorityLow(); make.top.equalTo(label.mas_top).with.priority(600);

// in public/private interface
@property (nonatomic, strong) MASConstraint *topConstraint; ... // when making constraints
[view1 mas_makeConstraints:^(MASConstraintMaker *make) { self.topConstraint = make.top.equalTo(superview.mas_top).with.offset(padding.top); make.left.equalTo(superview.mas_left).with.offset(padding.left); }]; ... // then later you can call
[self.topConstraint uninstall];

// this is Apple‘s recommended place for adding/updating constraints // this method can get called multiple times in response to setNeedsUpdateConstraints // which can be called by UIKit internally or in your code if you need to trigger an update to your constraints
- (void)updateConstraints { [self.growingButton mas_updateConstraints:^(MASConstraintMaker *make) { make.center.equalTo(self); make.width.equalTo(@(self.buttonSize.width)).priorityLow(); make.height.equalTo(@(self.buttonSize.height)).priorityLow(); make.width.lessThanOrEqualTo(self); make.height.lessThanOrEqualTo(self); }]; //according to apple super should be called at end of method
 [super updateConstraints]; }

mas_updateConstraints is useful for updating a set of constraints, but doing anything beyond updating constant values can get exhausting. That‘s where mas_remakeConstraints comes in.
 mas_remakeConstraints is similar to mas_updateConstraints, but instead of updating constant values, it will remove all of its contraints before installing them again. This lets you provide different constraints without having to keep around references to ones which you want to remove. - (void)changeButtonPosition { [self.button mas_remakeConstraints:^(MASConstraintMaker *make) { make.size.equalTo(self.buttonSize); if (topLeft) { make.top.and.left.offset(10); } else { make.bottom.and.right.offset(-10); } }]; }

Masonry adds a category to NSLayoutConstraint which overrides the default implementation of - (NSString *)description. Now you can give meaningful names to views and constraints, and also easily pick out the constraints created by Masonry.

Copy the included code snippets to ~/Library/Developer/Xcode/UserData/CodeSnippets to write your masonry blocks at lightning speed! mas_make -> [<view> mas_makeConstraints:^(MASConstraintMaker *make){<code>}]; mas_update -> [<view> mas_updateConstraints:^(MASConstraintMaker *make){<code>}]; mas_remake -> [<view> mas_remakeConstraints:^(MASConstraintMaker *make){<code>}];