1.自定义UITextField.placeholder颜色
新建UITextField类别
.h
@interface UITextField (LXExtension)
/** 占位文字颜色 */
@property (nonatomic, strong) UIColor *lx_placeholderColor;
@end
.m
@implementation UITextField (LXExtension)
/** 通过这个属性名，就可以修改textField内部的占位文字颜色 */
static NSString * const LXPlaceholderColorKeyPath = @"placeholderLabel.textColor";
/**
* 设置占位文字颜色
*/
- (void)setLx_placeholderColor:(UIColor *)lx_placeholderColor
{
// 这3行代码的作用：1> 保证创建出placeholderLabel，2> 保留曾经设置过的占位文字
NSString *placeholder = self.placeholder;
self.placeholder = @" ";
self.placeholder = placeholder;
// 处理xmg_placeholderColor为nil的情况：如果是nil，恢复成默认的占位文字颜色
if (lx_placeholderColor == nil) {
lx_placeholderColor = [UIColor colorWithRed:0 green:0 blue:0.0980392 alpha:0.22];
}
// 设置占位文字颜色
[self setValue:lx_placeholderColor forKeyPath:LXPlaceholderColorKeyPath];
}
/**
* 获得占位文字颜色
*/
- (UIColor *)lx_placeholderColor
{
return [self valueForKeyPath:LXPlaceholderColorKeyPath];
}
@end
2.快速自定义导航栏按钮
新建UIBarButtonItem类别
.h
@interface UIBarButtonItem (LXExtension)
+ (instancetype)lx_itemWithImage:(NSString *)image highImage:(NSString *)highImage target:(id)target action:(SEL)action;
@end
.m
@implementation UIBarButtonItem (XMGExtension)
+ (instancetype)lx_itemWithImage:(NSString *)image highImage:(NSString *)highImage target:(id)target action:(SEL)action
{
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button setImage:[UIImage imageNamed:image] forState:UIControlStateNormal];
[button setImage:[UIImage imageNamed:highImage] forState:UIControlStateHighlighted];
[button sizeToFit];
[button addTarget:target action:action forControlEvents:UIControlEventTouchUpInside];
return [[self alloc] initWithCustomView:button];
}
@end
3.计算文件大小,生成缓存,计算文本尺寸
新建NSString类别
.h
@interface NSString (LXExtension)
/**
* md5加密
*/
+ (NSString*)md5HexDigest:(NSString*)input;
/**
* 根据文件名计算出文件大小
*/
- (unsigned long long)lx_fileSize;
/**
* 生成缓存目录全路径
*/
- (instancetype)cacheDir;
/**
* 生成文档目录全路径
*/
- (instancetype)docDir;
/**
* 生成临时目录全路径
*/
- (instancetype)tmpDir;
/**
* @brief 根据字数的不同,返回UILabel中的text文字需要占用多少Size
* @param size 约束的尺寸
* @param font 文本字体
* @return 文本的实际尺寸
*/
- (CGSize)textSizeWithContentSize:(CGSize)size font:(UIFont *)font;
/**
* @brief 根据文本字数/文本宽度约束/文本字体 求得text的Size
* @param width 宽度约束
* @param font 文本字体
* @return 文本的实际高度
*/
- (CGFloat)textHeightWithContentWidth:(CGFloat)width font:(UIFont *)font;
/**
* @brief 根据文本字数/文本宽度约束/文本字体 求得text的Size
* @param height 宽度约束
* @param font 文本字体
* @return 文本的实际长度
*/
- (CGFloat)textWidthWithContentHeight:(CGFloat)height font:(UIFont *)font;
@end
.m
#import "NSString+LXExtension.h"
#import <objc/runtime.h>
#import <CommonCrypto/CommonDigest.h>
/*CC_MD5_DIGEST_LENGTH*/
#define MD5_LENGTH 32
@implementation NSString (LXExtension)
+ (NSString*)md5HexDigest:(NSString*)input {
const char* str = [input UTF8String];
unsigned char result[CC_MD5_DIGEST_LENGTH];
CC_MD5(str, strlen(str), result);
NSMutableString *ret = [NSMutableString stringWithCapacity:CC_MD5_DIGEST_LENGTH*2];
for(int i = 0; i<CC_MD5_DIGEST_LENGTH; i++) {
[ret appendFormat:@"%02x",result[i]];
}
return ret;
}
- (unsigned long long)lx_fileSize
{
// 计算self这个文件夹\文件的大小
// 文件管理者
NSFileManager *mgr = [NSFileManager defaultManager];
// 文件类型
NSDictionary *attrs = [mgr attributesOfItemAtPath:self error:nil];
NSString *fileType = attrs.fileType;
if ([fileType isEqualToString:NSFileTypeDirectory]) { // 文件夹
// 获得文件夹的遍历器
NSDirectoryEnumerator *enumerator = [mgr enumeratorAtPath:self];
// 总大小
unsigned long long fileSize = 0;
// 遍历所有子路径
for (NSString *subpath in enumerator) {
// 获得子路径的全路径
NSString *fullSubpath = [self stringByAppendingPathComponent:subpath];
fileSize += [mgr attributesOfItemAtPath:fullSubpath error:nil].fileSize;
}
return fileSize;
}
// 文件
return attrs.fileSize;
}
- (instancetype)cacheDir
{
NSString *dir = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject];
return [dir stringByAppendingPathComponent:[self lastPathComponent]];
}
- (instancetype)docDir
{
NSString *dir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
return [dir stringByAppendingPathComponent:[self lastPathComponent]];
}
- (instancetype)tmpDir
{
NSString *dir = NSTemporaryDirectory();
return [dir stringByAppendingPathComponent:[self lastPathComponent]];
}
- (CGSize)textSizeWithContentSize:(CGSize)size font:(UIFont *)font {
return [self boundingRectWithSize:size options:NSStringDrawingUsesLineFragmentOrigin attributes:@{NSFontAttributeName : font} context:nil].size;
}
- (CGFloat)textHeightWithContentWidth:(CGFloat)width font:(UIFont *)font {
CGSize size = CGSizeMake(width, MAXFLOAT);
return [self textSizeWithContentSize:size font:font].height;
}
- (CGFloat)textWidthWithContentHeight:(CGFloat)height font:(UIFont *)font {
CGSize size = CGSizeMake(MAXFLOAT, height);
return [self textSizeWithContentSize:size font:font].width;
}
@end
