Resigned cell height logic which in returned fixed a lagging issue with the showing/hiding of the keyboard

Author: evilpenguin

ARMRef/ARMRef/Source/CollectionView/ACollectionViewCell.h

@@ -31,7 +31,7 @@ NS_ASSUME_NONNULL_BEGIN
 @property (nonatomic, readonly, class) NSString *identifier;
 @property (nonatomic, weak) AInstruction *instruction;
 
-- (CGFloat) maxSizeForInstruction:(AInstruction *)instruction withWidth:(CGFloat)width;
++ (CGFloat) heightForInstruction:(AInstruction *)instruction withWidth:(CGFloat)width;
 
 @end
 

ARMRef/ARMRef/Source/CollectionView/ACollectionViewCell.m

@@ -53,13 +53,15 @@ - (instancetype) initWithFrame:(CGRect)frame {
 - (void) layoutSubviews {
     [super layoutSubviews];
 
+    CGFloat width = self.bounds.size.width;
+    
     // Top label
-    CGSize topSize = [self.topLabel sizeThatFits:CGSizeMake(self.contentView.bounds.size.width - 20.0f, CGFLOAT_MAX)];
-    self.topLabel.frame = CGRectMake(10.0f, 9.0f, topSize.width, topSize.height);
+    CGRect topFrame = [self.class _topLabelFrameForString:self.topLabel.text withWidth:width];
+    self.topLabel.frame = CGRectMake(10.0f, 9.0f, topFrame.size.width, topFrame.size.height);
 
     // Bottom label
-    CGSize bottomSize = [self.bottomLabel sizeThatFits:CGSizeMake(self.contentView.bounds.size.width - 20.0f, CGFLOAT_MAX)];
-    self.bottomLabel.frame = CGRectMake(10.0f, CGRectGetMaxY(self.topLabel.frame), bottomSize.width, bottomSize.height);
+    CGRect bottomFrame = [self.class _bottomLabelFrameForString:self.bottomLabel.text withWidth:width];
+    self.bottomLabel.frame = CGRectMake(10.0f, CGRectGetMaxY(self.topLabel.frame), bottomFrame.size.width, bottomFrame.size.height);
 }
 
 - (void)drawRect:(CGRect)rect {
@@ -80,15 +82,40 @@ + (NSString *) identifier {
 
 #pragma mark - Public methods
 
-- (CGFloat) maxSizeForInstruction:(AInstruction *)instruction withWidth:(CGFloat)width {
-    self.topLabel.text = instruction.mnemonic;
-    self.bottomLabel.text = instruction.shortDesc;
-    
++ (CGFloat) heightForInstruction:(AInstruction *)instruction withWidth:(CGFloat)width {
     CGFloat padding = 18.0f;
-    CGSize topSize = [self.topLabel sizeThatFits:CGSizeMake(width, CGFLOAT_MAX)];
-    CGSize bottomSize = [self.bottomLabel sizeThatFits:CGSizeMake(width, CGFLOAT_MAX)];
+    CGRect topFrame = [self _topLabelFrameForString:instruction.mnemonic withWidth:width];
+    CGRect bottomFrame = [self _bottomLabelFrameForString:instruction.shortDesc withWidth:width];
+
+    return topFrame.size.height + bottomFrame.size.height + padding;
+}
+
+#pragma mark - Private class
+
++ (CGRect) _topLabelFrameForString:(NSString *)string withWidth:(CGFloat)width {
+    return  [string boundingRectWithSize:CGSizeMake(width, CGFLOAT_MAX)
+                                 options:NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading
+                              attributes:self._topLabelAttributes
+                                 context:nil];
+}
+
++ (NSDictionary *) _topLabelAttributes {
+    return @{
+        NSFontAttributeName: [UIFont systemFontOfSize:20.0f weight:UIFontWeightBold]
+    };
+}
+
++ (CGRect) _bottomLabelFrameForString:(NSString *)string withWidth:(CGFloat)width {
+    return  [string boundingRectWithSize:CGSizeMake(width, CGFLOAT_MAX)
+                                 options:NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading
+                              attributes:self._bottomLabelAttributes
+                                 context:nil];
+}
 
-    return topSize.height + bottomSize.height + padding;
++ (NSDictionary *) _bottomLabelAttributes {
+    return @{
+        NSFontAttributeName: [UIFont systemFontOfSize:14.0f weight:UIFontWeightRegular]
+    };
 }
 
 #pragma mark - Setters
@@ -102,8 +129,8 @@ - (void) setHighlighted:(BOOL)highlighted {
 - (void) setInstruction:(AInstruction *)instruction {
     _instruction = instruction;
 
-    self.topLabel.text = instruction.mnemonic;
-    self.bottomLabel.text = instruction.shortDesc;
+    self.topLabel.attributedText = [[NSAttributedString alloc] initWithString:instruction.mnemonic attributes:self.class._topLabelAttributes];
+    self.bottomLabel.attributedText = [[NSAttributedString alloc] initWithString:instruction.shortDesc attributes:self.class._bottomLabelAttributes];
 
     [self setNeedsLayout];
 }
@@ -114,7 +141,6 @@ - (UILabel *) topLabel {
     if (!_topLabel) {
         _topLabel = [[UILabel alloc] init];
         _topLabel.backgroundColor = UIColor.clearColor;
-        _topLabel.font = [UIFont systemFontOfSize:20.0f weight:UIFontWeightBold];
         _topLabel.textColor = UIColor.blackColor;
         _topLabel.numberOfLines = 2;
     }
@@ -126,7 +152,6 @@ - (UILabel *) bottomLabel {
     if (!_bottomLabel) {
         _bottomLabel = [[UILabel alloc] init];
         _bottomLabel.backgroundColor = UIColor.clearColor;
-        _bottomLabel.font = [UIFont systemFontOfSize:14.0f weight:UIFontWeightRegular];
         _bottomLabel.textColor = UIColor.blackColor;
         _bottomLabel.numberOfLines = 0;
         _bottomLabel.lineBreakMode = NSLineBreakByWordWrapping;

ARMRef/ARMRef/Source/CollectionView/ACollectionViewDataHandle.m

@@ -36,7 +36,6 @@ @implementation ACollectionViewDataHandle
 
 - (nonnull __kindof UICollectionViewCell *) collectionView:(nonnull UICollectionView *)collectionView cellForItemAtIndexPath:(nonnull NSIndexPath *)indexPath {
     ACollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:ACollectionViewCell.identifier forIndexPath:indexPath];
-    cell.instruction = safetyObjectAtIndex(self.instructions, indexPath.row);
 
     return cell;
 }
@@ -47,6 +46,10 @@ - (NSInteger) collectionView:(nonnull UICollectionView *)collectionView numberOf
 
 #pragma mark - UICollectionViewDelegate
 
+- (void)collectionView:(UICollectionView *)collectionView willDisplayCell:(ACollectionViewCell *)cell forItemAtIndexPath:(NSIndexPath *)indexPath {
+    cell.instruction = safetyObjectAtIndex(self.instructions, indexPath.row);
+}
+
 - (void) collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {
     [self.handleTouch collectioinViewHandle:self didTouchInstruction:self.instructions[indexPath.row]];
 }
@@ -64,10 +67,8 @@ - (void)collectionView:(UICollectionView *)collectionView didUnhighlightItemAtIn
 #pragma mark - UICollectionViewDelegateFlowLayout
 
 - (CGSize) collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
-    ACollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:ACollectionViewCell.identifier forIndexPath:indexPath];
-    cell.instruction = safetyObjectAtIndex(self.instructions, indexPath.row);
-    
-    CGFloat maxSize = [cell maxSizeForInstruction:self.instructions[indexPath.row] withWidth:collectionView.bounds.size.width - 20.0f];
+    CGFloat maxSize = [ACollectionViewCell heightForInstruction:safetyObjectAtIndex(self.instructions, indexPath.row)
+                                                      withWidth:collectionView.bounds.size.width - 20.0f];
 
     return CGSizeMake(collectionView.bounds.size.width - 20.0f, maxSize);
 }

ARMRef/ARMRef/Source/Main/AMainViewController.m

@@ -190,10 +190,10 @@ - (void) searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText
 }
 
 - (void) searchBarCancelButtonClicked:(UISearchBar *)searchBar {
-    [self _updateDataAndLoaderWithString:nil];
-    
     searchBar.text = nil;
     [searchBar resignFirstResponder];
+    
+    [self _updateDataAndLoaderWithString:nil];
 }
 
 - (void) searchBarSearchButtonClicked:(UISearchBar *)searchBar {