Swiftgram/AsyncDisplayKit/Layout/ASStackLayoutSpec.h
Huy Nguyen 2149d44990 Fix naming convetion:
- "Layout node" is changed to "layout spec".
- Update tests.
- Update Kittens sample.
2015-07-01 18:13:44 +07:00

88 lines
3.6 KiB
Objective-C

/*
* Copyright (c) 2014-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
*/
#import <AsyncDisplayKit/ASLayoutSpec.h>
typedef NS_ENUM(NSUInteger, ASStackLayoutDirection) {
ASStackLayoutDirectionVertical,
ASStackLayoutDirectionHorizontal,
};
/** If no children are flexible, how should this spec justify its children in the available space? */
typedef NS_ENUM(NSUInteger, ASStackLayoutJustifyContent) {
/**
On overflow, children overflow out of this spec's bounds on the right/bottom side.
On underflow, children are left/top-aligned within this spec's bounds.
*/
ASStackLayoutJustifyContentStart,
/**
On overflow, children are centered and overflow on both sides.
On underflow, children are centered within this spec's bounds in the stacking direction.
*/
ASStackLayoutJustifyContentCenter,
/**
On overflow, children overflow out of this spec's bounds on the left/top side.
On underflow, children are right/bottom-aligned within this spec's bounds.
*/
ASStackLayoutJustifyContentEnd,
};
typedef NS_ENUM(NSUInteger, ASStackLayoutAlignItems) {
/** Align children to start of cross axis */
ASStackLayoutAlignItemsStart,
/** Align children with end of cross axis */
ASStackLayoutAlignItemsEnd,
/** Center children on cross axis */
ASStackLayoutAlignItemsCenter,
/** Expand children to fill cross axis */
ASStackLayoutAlignItemsStretch,
};
typedef struct {
/** Specifies the direction children are stacked in. */
ASStackLayoutDirection direction;
/** The amount of space between each child. */
CGFloat spacing;
/** How children are aligned if there are no flexible children. */
ASStackLayoutJustifyContent justifyContent;
/** Orientation of children along cross axis */
ASStackLayoutAlignItems alignItems;
} ASStackLayoutSpecStyle;
/**
A simple layout spec that stacks a list of children vertically or horizontally.
- All children are initially laid out with the an infinite available size in the stacking direction.
- In the other direction, this spec's constraint is passed.
- The children's sizes are summed in the stacking direction.
- If this sum is less than this spec's minimum size in stacking direction, children with flexGrow are flexed.
- If it is greater than this spec's maximum size in the stacking direction, children with flexShrink are flexed.
- If, even after flexing, the sum is still greater than this spec's maximum size in the stacking direction,
justifyContent determines how children are laid out.
For example:
- Suppose stacking direction is Vertical, min-width=100, max-width=300, min-height=200, max-height=500.
- All children are laid out with min-width=100, max-width=300, min-height=0, max-height=INFINITY.
- If the sum of the childrens' heights is less than 200, children with flexGrow are flexed larger.
- If the sum of the childrens' heights is greater than 500, children with flexShrink are flexed smaller.
Each child is shrunk by `((sum of heights) - 500)/(number of flexShrink-able children)`.
- If the sum of the childrens' heights is greater than 500 even after flexShrink-able children are flexed,
justifyContent determines how children are laid out.
*/
@interface ASStackLayoutSpec : ASLayoutSpec
/**
@param style Specifies how children are laid out.
@param children ASLayoutable children to be positioned.
*/
+ (instancetype)newWithStyle:(ASStackLayoutSpecStyle)style children:(NSArray *)children;
@end