GradientLabel.h
#import <UIKit/UIKit.h>
@interface GradientLabel : UIView
@property (nonatomic, strong) NSArray * colors;//字型漸變顔色數組(必須将顔色轉換為CGColor并強制轉換為id類型)
@property (nonatomic, strong) UIFont *font;//字型
@property (nonatomic, copy) NSString *text;//設定漸變顔色的文字
@property (nonatomic, assign) NSTextAlignment textAlignment;//對齊方式
@property (nonatomic, assign) CGPoint startPoint;//起始點(0.0~1.0)
@property (nonatomic, assign) CGPoint endPoint;//結束點(0.0~1.0)
//應用設定
- (void) setGradientLabel;
@end
GradientLabel.m
#import "GradientLabel.h"
@interface GradientLabel ()
@property (nonatomic, strong) UILabel *label;
@property (nonatomic, strong) CAGradientLayer *gradientLayer;
@end
@implementation GradientLabel
- (CAGradientLayer *)gradientLayer {
if (!_gradientLayer) {
_gradientLayer = [CAGradientLayer layer];
_gradientLayer.startPoint = CGPointMake(0.0,1.0);
_gradientLayer.endPoint = CGPointMake(1.0, 1.0);
_gradientLayer.frame = self.label.frame;
_gradientLayer.colors = self.colors?:@[[UIColor whiteColor], [UIColor blackColor]];
}
return _gradientLayer;
}
- (void) setGradientLabel {
self.label = [[UILabel alloc] init];
self.label.text = self.text?:@"漸變字型";
[self.label setFont:self.font?:[UIFont systemFontOfSize:13]];
[self.label setTextAlignment:self.textAlignment?:kCTLeftTextAlignment];
[self addSubview:self.label];
}
-(void)layoutSubviews {
[super layoutSubviews];
[self.label setFrame:self.bounds];
// 添加漸變層到控制器的view圖層上
[self.layer addSublayer:self.gradientLayer];
// mask層工作原理:按照透明度裁剪,隻保留非透明部分,文字就是非透明的,是以除了文字,其他都被裁剪掉,這樣就隻會顯示文字下面漸變層的内容,相當于留了文字的區域,讓漸變層去填充文字的顔色。
// 設定漸變層的裁剪層
self.gradientLayer.mask = self.label.layer;
}
@end
代碼位址:https://github.com/15736882551/GCGradientLabel