前言
- 系統(tǒng)Api提供的
textAlignment位置我們一般只會用到左邊、右邊、中間三種顯示方式，于是寫個分類提供更多的顯示位置，分別包含左上、右上、左下、右下、中上、中下 - 采用Category的方式處理，簡單方便使用
GitHub地址：KJCategories
簡單介紹 Property & API
NS_ASSUME_NONNULL_BEGIN
/// Label 文本顯示樣式
typedef NS_ENUM(NSUInteger, KJLabelTextAlignmentType) {
KJLabelTextAlignmentTypeLeft = 0,
KJLabelTextAlignmentTypeRight,
KJLabelTextAlignmentTypeCenter,
KJLabelTextAlignmentTypeLeftTop,
KJLabelTextAlignmentTypeRightTop,
KJLabelTextAlignmentTypeLeftBottom,
KJLabelTextAlignmentTypeRightBottom,
KJLabelTextAlignmentTypeTopCenter,
KJLabelTextAlignmentTypeBottomCenter,
};
@interface UILabel (KJExtension)
/// 設(shè)置文字內(nèi)容顯示位置，外部不需要再去設(shè)置 " textAlignment " 屬性
@property(nonatomic,assign)KJLabelTextAlignmentType kTextAlignmentType;
/// 獲取高度
- (CGFloat)kj_calculateHeightWithWidth:(CGFloat)width;
/// 獲取高度，指定行高
- (CGFloat)kj_calculateHeightWithWidth:(CGFloat)width OneLineHeight:(CGFloat)height;
/// 獲取文字尺寸
+ (CGSize)kj_calculateLabelSizeWithTitle:(NSString*)title font:(UIFont*)font constrainedToSize:(CGSize)size lineBreakMode:(NSLineBreakMode)lineBreakMode;
@end
NS_ASSUME_NONNULL_END
1. kTextAlignmentType 設(shè)置文本位置，
這里需要注意的就是內(nèi)部有使用到系統(tǒng)的textAlignment屬性，因此調(diào)用該屬性的話，則不需要調(diào)用textAlignment屬性
使用示例
CGFloat x,y;
CGFloat sp = kAutoW(10);
CGFloat w = (kScreenW-sp*4)/3.;
CGFloat h = w*9/16;
NSArray *names = @[@"左邊",@"右邊",@"中間",@"左上",@"右上",@"左下",@"右下",@"中上",@"中下"];
NSInteger types[9] = {
KJLabelTextAlignmentTypeLeft,
KJLabelTextAlignmentTypeRight,
KJLabelTextAlignmentTypeCenter,
KJLabelTextAlignmentTypeLeftTop,
KJLabelTextAlignmentTypeRightTop,
KJLabelTextAlignmentTypeLeftBottom,
KJLabelTextAlignmentTypeRightBottom,
KJLabelTextAlignmentTypeTopCenter,
KJLabelTextAlignmentTypeBottomCenter
};
for (int k=0; k<names.count; k++) {
x = k%3*(w+sp)+sp;
y = k/3*(h+sp)+sp+64+sp*2;
UILabel *label = [UILabel kj_createLabelWithText:names[k] FontSize:16 TextColor:UIColor.orangeColor];
label.backgroundColor = [UIColor.orangeColor colorWithAlphaComponent:0.2];
label.kTextAlignmentType = types[k];
label.borderWidth = 1;
label.borderColor = UIColor.orangeColor;
label.frame = CGRectMake(x, y, w, h);
[self.view addSubview:label];
}
Category
//
// UILabel+KJExtension.m
// KJCategories
//
// Created by 楊科軍 on 2020/9/24.
// Copyright ? 2020 楊科軍. All rights reserved.
// https://github.com/yangKJ/KJExtensionHandler
#import "UILabel+KJExtension.h"
#import <objc/runtime.h>
@implementation UILabel (KJExtension)
- (KJLabelTextAlignmentType)kTextAlignmentType{
return (KJLabelTextAlignmentType)[objc_getAssociatedObject(self, @selector(kTextAlignmentType)) integerValue];
}
- (void)setKTextAlignmentType:(KJLabelTextAlignmentType)kTextAlignmentType{
objc_setAssociatedObject(self, @selector(kTextAlignmentType), @(kTextAlignmentType), OBJC_ASSOCIATION_ASSIGN);
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
method_exchangeImplementations(class_getInstanceMethod(self.class, @selector(drawTextInRect:)), class_getInstanceMethod(self.class, @selector(kj_drawTextInRect:)));
});
switch (kTextAlignmentType) {
case KJLabelTextAlignmentTypeRight:
case KJLabelTextAlignmentTypeRightTop:
case KJLabelTextAlignmentTypeRightBottom:
self.textAlignment = NSTextAlignmentRight;
break;
case KJLabelTextAlignmentTypeLeft:
case KJLabelTextAlignmentTypeLeftTop:
case KJLabelTextAlignmentTypeLeftBottom:
self.textAlignment = NSTextAlignmentLeft;
break;
case KJLabelTextAlignmentTypeCenter:
case KJLabelTextAlignmentTypeTopCenter:
case KJLabelTextAlignmentTypeBottomCenter:
self.textAlignment = NSTextAlignmentCenter;
break;
default:
break;
}
}
- (void)kj_drawTextInRect:(CGRect)rect{
switch (self.kTextAlignmentType) {
case KJLabelTextAlignmentTypeRight:
case KJLabelTextAlignmentTypeLeft:
case KJLabelTextAlignmentTypeCenter:
[self kj_drawTextInRect:rect];
break;
case KJLabelTextAlignmentTypeBottomCenter:
case KJLabelTextAlignmentTypeLeftBottom:
case KJLabelTextAlignmentTypeRightBottom:{
CGRect textRect = [self textRectForBounds:rect limitedToNumberOfLines:self.numberOfLines];
textRect.origin = CGPointMake(textRect.origin.x, -CGRectGetMaxY(textRect)+rect.size.height);
[self kj_drawTextInRect:textRect];
}
break;
default:{
CGRect textRect = [self textRectForBounds:rect limitedToNumberOfLines:self.numberOfLines];
[self kj_drawTextInRect:textRect];
}
break;
}
}
/// 獲取高度
- (CGFloat)kj_calculateHeightWithWidth:(CGFloat)width{
self.numberOfLines = 0;
self.lineBreakMode = NSLineBreakByCharWrapping;
CGSize size = [UILabel kj_calculateLabelSizeWithTitle:self.text font:self.font constrainedToSize:CGSizeMake(width, MAXFLOAT) lineBreakMode:NSLineBreakByCharWrapping];
size.height += 3;
return size.height;
}
/// 獲取高度，指定行高
- (CGFloat)kj_calculateHeightWithWidth:(CGFloat)width OneLineHeight:(CGFloat)height{
self.numberOfLines = 0;
self.lineBreakMode = NSLineBreakByCharWrapping;
CGSize size = [UILabel kj_calculateLabelSizeWithTitle:self.text font:self.font constrainedToSize:CGSizeMake(width, MAXFLOAT) lineBreakMode:NSLineBreakByCharWrapping];
return size.height * height / self.font.lineHeight;
}
/// 獲取文字尺寸
+ (CGSize)kj_calculateLabelSizeWithTitle:(NSString*)title font:(UIFont*)font constrainedToSize:(CGSize)size lineBreakMode:(NSLineBreakMode)lineBreakMode{
if (title.length == 0) return CGSizeZero;
NSMutableParagraphStyle *paragraph = [[NSMutableParagraphStyle alloc] init];
paragraph.lineBreakMode = lineBreakMode;
CGRect frame = [title boundingRectWithSize:size options:NSStringDrawingUsesLineFragmentOrigin attributes:@{NSFontAttributeName:font,NSParagraphStyleAttributeName:paragraph} context:nil];
return frame.size;
}
@end
