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// The MIT License (MIT)
//
// Copyright (c) 2015-2016 forkingdog ( https://github.com/forkingdog )
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
#import "UITableView+FDTemplateLayoutCell.h"
#import <objc/runtime.h>
@implementation UITableView (FDTemplateLayoutCell)
- (__kindof UITableViewCell *)fd_templateCellForReuseIdentifier:(NSString *)identifier {
NSAssert(identifier.length > 0, @"Expect a valid identifier - %@", identifier);
NSMutableDictionary<NSString *, __kindof UITableViewCell *> *templateCellsByIdentifiers = objc_getAssociatedObject(self, _cmd);
if (!templateCellsByIdentifiers) {
templateCellsByIdentifiers = @{}.mutableCopy;
objc_setAssociatedObject(self, _cmd, templateCellsByIdentifiers, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
UITableViewCell *templateCell = templateCellsByIdentifiers[identifier];
if (!templateCell) {
templateCell = [self dequeueReusableCellWithIdentifier:identifier];
NSAssert(templateCell != nil, @"Cell must be registered to table view for identifier - %@", identifier);
templateCell.fd_isTemplateLayoutCell = YES;
templateCell.contentView.translatesAutoresizingMaskIntoConstraints = NO;
templateCellsByIdentifiers[identifier] = templateCell;
[self fd_debugLog:[NSString stringWithFormat:@"layout cell created - %@", identifier]];
}
return templateCell;
}
- (CGFloat)fd_heightForCellWithIdentifier:(NSString *)identifier configuration:(void (^)(id cell))configuration {
if (!identifier) {
return 0;
}
UITableViewCell *templateLayoutCell = [self fd_templateCellForReuseIdentifier:identifier];
// Manually calls to ensure consistent behavior with actual cells (that are displayed on screen).
[templateLayoutCell prepareForReuse];
// Customize and provide content for our template cell.
if (configuration) {
configuration(templateLayoutCell);
}
CGFloat contentViewWidth = CGRectGetWidth(self.frame);
// If a cell has accessory view or system accessory type, its content view's width is smaller
// than cell's by some fixed values.
if (templateLayoutCell.accessoryView) {
contentViewWidth -= 16 + CGRectGetWidth(templateLayoutCell.accessoryView.frame);
} else {
static const CGFloat systemAccessoryWidths[] = {
[UITableViewCellAccessoryNone] = 0,
[UITableViewCellAccessoryDisclosureIndicator] = 34,
[UITableViewCellAccessoryDetailDisclosureButton] = 68,
[UITableViewCellAccessoryCheckmark] = 40,
[UITableViewCellAccessoryDetailButton] = 48
};
contentViewWidth -= systemAccessoryWidths[templateLayoutCell.accessoryType];
}
CGSize fittingSize = CGSizeZero;
if (templateLayoutCell.fd_enforceFrameLayout) {
// If not using auto layout, you have to override "-sizeThatFits:" to provide a fitting size by yourself.
// This is the same method used in iOS8 self-sizing cell's implementation.
// Note: fitting height should not include separator view.
SEL selector = @selector(sizeThatFits:);
BOOL inherited = ![templateLayoutCell isMemberOfClass:UITableViewCell.class];
BOOL overrided = [templateLayoutCell.class instanceMethodForSelector:selector] != [UITableViewCell instanceMethodForSelector:selector];
if (inherited && !overrided) {
NSAssert(NO, @"Customized cell must override '-sizeThatFits:' method if not using auto layout.");
}
fittingSize = [templateLayoutCell sizeThatFits:CGSizeMake(contentViewWidth, 0)];
} else {
// Add a hard width constraint to make dynamic content views (like labels) expand vertically instead
// of growing horizontally, in a flow-layout manner.
if (contentViewWidth > 0) {
NSLayoutConstraint *widthFenceConstraint = [NSLayoutConstraint constraintWithItem:templateLayoutCell.contentView attribute:NSLayoutAttributeWidth relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeNotAnAttribute multiplier:1.0 constant:contentViewWidth];
[templateLayoutCell.contentView addConstraint:widthFenceConstraint];
// Auto layout engine does its math
fittingSize = [templateLayoutCell.contentView systemLayoutSizeFittingSize:UILayoutFittingCompressedSize];
[templateLayoutCell.contentView removeConstraint:widthFenceConstraint];
}
}
// Add 1px extra space for separator line if needed, simulating default UITableViewCell.
if (self.separatorStyle != UITableViewCellSeparatorStyleNone) {
fittingSize.height += 1.0 / [UIScreen mainScreen].scale;
}
if (templateLayoutCell.fd_enforceFrameLayout) {
[self fd_debugLog:[NSString stringWithFormat:@"calculate using frame layout - %@", @(fittingSize.height)]];
} else {
[self fd_debugLog:[NSString stringWithFormat:@"calculate using auto layout - %@", @(fittingSize.height)]];
}
return fittingSize.height;
}
- (CGFloat)fd_heightForCellWithIdentifier:(NSString *)identifier cacheByIndexPath:(NSIndexPath *)indexPath configuration:(void (^)(id cell))configuration {
if (!identifier || !indexPath) {
return 0;
}
// Hit cache
if ([self.fd_indexPathHeightCache existsHeightAtIndexPath:indexPath]) {
[self fd_debugLog:[NSString stringWithFormat:@"hit cache by index path[%@:%@] - %@", @(indexPath.section), @(indexPath.row), @([self.fd_indexPathHeightCache heightForIndexPath:indexPath])]];
return [self.fd_indexPathHeightCache heightForIndexPath:indexPath];
}
CGFloat height = [self fd_heightForCellWithIdentifier:identifier configuration:configuration];
[self.fd_indexPathHeightCache cacheHeight:height byIndexPath:indexPath];
[self fd_debugLog:[NSString stringWithFormat: @"cached by index path[%@:%@] - %@", @(indexPath.section), @(indexPath.row), @(height)]];
return height;
}
- (CGFloat)fd_heightForCellWithIdentifier:(NSString *)identifier cacheByKey:(id<NSCopying>)key configuration:(void (^)(id cell))configuration {
if (!identifier || !key) {
return 0;
}
// Hit cache
if ([self.fd_keyedHeightCache existsHeightForKey:key]) {
CGFloat cachedHeight = [self.fd_keyedHeightCache heightForKey:key];
[self fd_debugLog:[NSString stringWithFormat:@"hit cache by key[%@] - %@", key, @(cachedHeight)]];
return cachedHeight;
}
CGFloat height = [self fd_heightForCellWithIdentifier:identifier configuration:configuration];
[self.fd_keyedHeightCache cacheHeight:height byKey:key];
[self fd_debugLog:[NSString stringWithFormat:@"cached by key[%@] - %@", key, @(height)]];
return height;
}
@end
@implementation UITableViewCell (FDTemplateLayoutCell)
- (BOOL)fd_isTemplateLayoutCell {
return [objc_getAssociatedObject(self, _cmd) boolValue];
}
- (void)setFd_isTemplateLayoutCell:(BOOL)isTemplateLayoutCell {
objc_setAssociatedObject(self, @selector(fd_isTemplateLayoutCell), @(isTemplateLayoutCell), OBJC_ASSOCIATION_RETAIN);
}
- (BOOL)fd_enforceFrameLayout {
return [objc_getAssociatedObject(self, _cmd) boolValue];
}
- (void)setFd_enforceFrameLayout:(BOOL)enforceFrameLayout {
objc_setAssociatedObject(self, @selector(fd_enforceFrameLayout), @(enforceFrameLayout), OBJC_ASSOCIATION_RETAIN);
}
@end