| // Copyright 2019-present the Material Components for iOS authors. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #import "MDCTextControlAssistiveLabelViewLayout.h" |
| |
| @interface MDCTextControlAssistiveLabelViewLayout () |
| |
| @property(nonatomic, assign) CGRect leadingAssistiveLabelFrame; |
| @property(nonatomic, assign) CGRect trailingAssistiveLabelFrame; |
| @property(nonatomic, assign) CGFloat calculatedHeight; |
| |
| @end |
| |
| @implementation MDCTextControlAssistiveLabelViewLayout |
| |
| #pragma mark Object Lifecycle |
| |
| - (instancetype)initWithWidth:(CGFloat)superviewWidth |
| leadingAssistiveLabel:(UILabel *)leadingAssistiveLabel |
| trailingAssistiveLabel:(UILabel *)trailingAssistiveLabel |
| assistiveLabelDrawPriority: |
| (MDCTextControlAssistiveLabelDrawPriority)assistiveLabelDrawPriority |
| customAssistiveLabelDrawPriority:(CGFloat)customAssistiveLabelDrawPriority |
| horizontalPadding:(CGFloat)horizontalPadding |
| paddingAboveAssistiveLabels:(CGFloat)paddingAboveAssistiveLabels |
| paddingBelowAssistiveLabels:(CGFloat)paddingBelowAssistiveLabels |
| isRTL:(BOOL)isRTL { |
| self = [super init]; |
| if (self) { |
| [self calculateLayoutWithSuperviewWidth:superviewWidth |
| leadingAssistiveLabel:leadingAssistiveLabel |
| trailingAssistiveLabel:trailingAssistiveLabel |
| assistiveLabelDrawPriority:assistiveLabelDrawPriority |
| customAssistiveLabelDrawPriority:customAssistiveLabelDrawPriority |
| horizontalPadding:horizontalPadding |
| paddingAboveAssistiveLabels:(CGFloat)paddingAboveAssistiveLabels |
| paddingBelowAssistiveLabels:(CGFloat)paddingBelowAssistiveLabels |
| isRTL:isRTL]; |
| return self; |
| } |
| return nil; |
| } |
| |
| #pragma mark Layout Calculation |
| |
| - (void)calculateLayoutWithSuperviewWidth:(CGFloat)superviewWidth |
| leadingAssistiveLabel:(UILabel *)leadingAssistiveLabel |
| trailingAssistiveLabel:(UILabel *)trailingAssistiveLabel |
| assistiveLabelDrawPriority: |
| (MDCTextControlAssistiveLabelDrawPriority)assistiveLabelDrawPriority |
| customAssistiveLabelDrawPriority:(CGFloat)customAssistiveLabelDrawPriority |
| horizontalPadding:(CGFloat)horizontalPadding |
| paddingAboveAssistiveLabels:(CGFloat)paddingAboveAssistiveLabels |
| paddingBelowAssistiveLabels:(CGFloat)paddingBelowAssistiveLabels |
| isRTL:(BOOL)isRTL { |
| CGFloat assistiveLabelsCombinedMinX = horizontalPadding; |
| CGFloat assistiveLabelsCombinedMaxX = superviewWidth - horizontalPadding; |
| CGFloat assistiveLabelsCombinedMaxWidth = |
| assistiveLabelsCombinedMaxX - assistiveLabelsCombinedMinX; |
| |
| CGFloat assistiveLabelsCombinedMinY = paddingAboveAssistiveLabels; |
| CGFloat leadingAssistiveLabelWidth = 0; |
| CGFloat trailingAssistiveLabelWidth = 0; |
| CGSize leadingAssistiveLabelSize = CGSizeZero; |
| CGSize trailingAssistiveLabelSize = CGSizeZero; |
| switch (assistiveLabelDrawPriority) { |
| case MDCTextControlAssistiveLabelDrawPriorityCustom: |
| leadingAssistiveLabelWidth = [self |
| leadingAssistiveLabelWidthWithCombinedAssistiveLabelsWidth:assistiveLabelsCombinedMaxWidth |
| customDrawPriority: |
| customAssistiveLabelDrawPriority]; |
| trailingAssistiveLabelWidth = assistiveLabelsCombinedMaxWidth - leadingAssistiveLabelWidth; |
| leadingAssistiveLabelSize = [self assistiveLabelSizeWithLabel:leadingAssistiveLabel |
| constrainedToWidth:leadingAssistiveLabelWidth]; |
| trailingAssistiveLabelSize = [self assistiveLabelSizeWithLabel:trailingAssistiveLabel |
| constrainedToWidth:trailingAssistiveLabelWidth]; |
| break; |
| case MDCTextControlAssistiveLabelDrawPriorityLeading: |
| leadingAssistiveLabelSize = |
| [self assistiveLabelSizeWithLabel:leadingAssistiveLabel |
| constrainedToWidth:assistiveLabelsCombinedMaxWidth]; |
| if ([self isLabelMultilineWithLabel:leadingAssistiveLabel size:leadingAssistiveLabelSize]) { |
| trailingAssistiveLabelSize = CGSizeZero; |
| } else { |
| trailingAssistiveLabelSize = |
| [self assistiveLabelSizeWithLabel:trailingAssistiveLabel |
| constrainedToWidth:assistiveLabelsCombinedMaxWidth - |
| leadingAssistiveLabelSize.width]; |
| } |
| break; |
| case MDCTextControlAssistiveLabelDrawPriorityTrailing: |
| // Pass through (.trailing is the default priority) |
| default: |
| trailingAssistiveLabelSize = |
| [self assistiveLabelSizeWithLabel:trailingAssistiveLabel |
| constrainedToWidth:assistiveLabelsCombinedMaxWidth]; |
| if ([self isLabelMultilineWithLabel:trailingAssistiveLabel size:trailingAssistiveLabelSize]) { |
| leadingAssistiveLabelSize = CGSizeZero; |
| } else { |
| leadingAssistiveLabelSize = |
| [self assistiveLabelSizeWithLabel:leadingAssistiveLabel |
| constrainedToWidth:assistiveLabelsCombinedMaxWidth - |
| trailingAssistiveLabelSize.width]; |
| } |
| break; |
| } |
| |
| BOOL leadingAssistiveLabelIsVisible = !CGSizeEqualToSize(leadingAssistiveLabelSize, CGSizeZero); |
| BOOL trailingAssistiveLabelIsVisible = !CGSizeEqualToSize(trailingAssistiveLabelSize, CGSizeZero); |
| if (!leadingAssistiveLabelIsVisible && !trailingAssistiveLabelIsVisible) { |
| self.leadingAssistiveLabelFrame = CGRectZero; |
| self.trailingAssistiveLabelFrame = CGRectZero; |
| self.calculatedHeight = 0; |
| return; |
| } |
| |
| CGSize leftAssistiveLabelSize = isRTL ? trailingAssistiveLabelSize : leadingAssistiveLabelSize; |
| CGSize rightAssistiveLabelSize = isRTL ? leadingAssistiveLabelSize : trailingAssistiveLabelSize; |
| CGRect leftAssistiveLabelFrame = CGRectZero; |
| CGRect rightAssistiveLabelFrame = CGRectZero; |
| if (!CGSizeEqualToSize(leftAssistiveLabelSize, CGSizeZero)) { |
| leftAssistiveLabelFrame = |
| CGRectMake(assistiveLabelsCombinedMinX, assistiveLabelsCombinedMinY, |
| leftAssistiveLabelSize.width, leftAssistiveLabelSize.height); |
| } |
| if (!CGSizeEqualToSize(rightAssistiveLabelSize, CGSizeZero)) { |
| rightAssistiveLabelFrame = CGRectMake( |
| assistiveLabelsCombinedMaxX - rightAssistiveLabelSize.width, assistiveLabelsCombinedMinY, |
| rightAssistiveLabelSize.width, rightAssistiveLabelSize.height); |
| } |
| |
| CGFloat maxAssistiveLabelHeight = |
| MAX(CGRectGetMaxY(leftAssistiveLabelFrame), CGRectGetMaxY(rightAssistiveLabelFrame)); |
| self.leadingAssistiveLabelFrame = isRTL ? rightAssistiveLabelFrame : leftAssistiveLabelFrame; |
| self.trailingAssistiveLabelFrame = isRTL ? leftAssistiveLabelFrame : rightAssistiveLabelFrame; |
| self.calculatedHeight = maxAssistiveLabelHeight + paddingBelowAssistiveLabels; |
| } |
| |
| - (CGSize)assistiveLabelSizeWithLabel:(UILabel *)label constrainedToWidth:(CGFloat)maxWidth { |
| if (maxWidth <= 0 || label.text.length <= 0 || label.hidden) { |
| return CGSizeZero; |
| } |
| CGSize fittingSize = CGSizeMake(maxWidth, CGFLOAT_MAX); |
| CGSize size = [label sizeThatFits:fittingSize]; |
| if (size.width > maxWidth) { |
| size.width = maxWidth; |
| } |
| return size; |
| } |
| |
| - (CGFloat)leadingAssistiveLabelWidthWithCombinedAssistiveLabelsWidth: |
| (CGFloat)totalAssistiveLabelsWidth |
| customDrawPriority:(CGFloat)customDrawPriority { |
| return customDrawPriority * totalAssistiveLabelsWidth; |
| } |
| |
| - (BOOL)isLabelMultilineWithLabel:(UILabel *)label size:(CGSize)size { |
| CGFloat lineHeight = label.font.lineHeight; |
| return round((double)(size.height / lineHeight)) > 1; |
| } |
| |
| @end |
