UILabel over UIProgressView有多种颜色
所以我还没有做到这一点，我正试图发挥如何做到这一点。 所以我创建了一个UITableView，每个单元格都有一个关联的NSTimer。 现在在每个自定义UITableViewCell中我都有一个UIProgressView作为背景，拉伸以填充单元格。 现在我想在UIProgressView上添加剩余时间的UILabel。 但由于进度条填充颜色和背景颜色明显不同（深蓝色进度填充和白色背景/非填充区域），我想知道如何在进度条填充时动态更改文本颜色。 就像海军蓝填充的UILabel部分一样，文本颜色应该是白色。 白色背景上的部分，文字应该是黑色的。 像这样的东西，但在目标c。
刚刚为你破解了这个:)
结果
这是ZWProgressView的模拟器结果：
视图控制器文件
这是一个示例用法：
#import "ViewController.h" #import "ZWProgressView.h" @interface ViewController () @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. ZWProgressView *progressView = [[ZWProgressView alloc] init]; progressView.frame = CGRectMake((self.view.bounds.size.width - 200) / 2.0, self.view.bounds.size.height / 2.0 - 25.0, 200, 50); progressView.progress = 0.47; [self.view addSubview:progressView]; } - (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated. } @end ZWProgressView类
注意：掩蔽代码取自：
只需用矩形屏蔽UIView即可
头文件
#import @interface ZWProgressView : UIView @property (nonatomic, assign) CGFloat progress; @property (nonatomic, strong) UIColor *normalTextColor; @property (nonatomic, strong) UIColor *maskedTextColor; @property (nonatomic, strong) UIView *container; @property (nonatomic, strong) UIView *progressBar; @property (nonatomic, strong) UILabel *progressLabel; @property (nonatomic, strong) UILabel *maskedProgressLabel; @property (nonatomic, strong) UIView *mask; @end
实施文件
#import "ZWProgressView.h" @interface ZWProgressView() { NSLayoutConstraint *progressBarWidthConstraint; NSLayoutConstraint *progressBarMaskWidthConstraint; } @end @implementation ZWProgressView - (id)initWithFrame:(CGRect)frame { self = [super initWithFrame:frame]; if (self) { // Initialization code self.frame = frame; [self initView]; [self addAllConstraints]; } return self; } -(void)initView { self.layer.cornerRadius = 2.0; self.backgroundColor = [UIColor colorWithRed:0.85 green:0.85 blue:0.85 alpha:1.0]; self.normalTextColor = [UIColor colorWithRed:0.2 green:0.2 blue:0.2 alpha:1.0]; self.maskedTextColor = [UIColor whiteColor]; self.container = [[UIView alloc] init]; self.container.layer.borderWidth = 1.0; self.container.layer.borderColor = [UIColor grayColor].CGColor; self.container.backgroundColor = [UIColor whiteColor]; self.container.layer.cornerRadius = 3.0; self.container.clipsToBounds = YES; self.progressBar = [[UIView alloc] init]; self.progressBar.backgroundColor = [UIColor colorWithRed:0.2 green:0.3 blue:0.8 alpha:1.0]; self.progressLabel = [[UILabel alloc] init]; self.progressLabel.font = [UIFont fontWithName:@"Arial-BoldMT" size:30]; self.progressLabel.textAlignment = NSTextAlignmentCenter; self.progressLabel.textColor = self.normalTextColor; self.progressLabel.clipsToBounds = YES; self.maskedProgressLabel = [[UILabel alloc] init]; self.maskedProgressLabel.font = self.progressLabel.font; self.maskedProgressLabel.textAlignment = self.progressLabel.textAlignment; self.maskedProgressLabel.textColor = self.maskedTextColor; self.maskedProgressLabel.clipsToBounds = YES; self.mask = [[UIView alloc] init]; [self.container addSubview:self.progressBar]; [self.container addSubview:self.progressLabel]; [self.container addSubview:self.maskedProgressLabel]; [self.container addSubview:self.mask]; [self addSubview:self.container]; } -(void)addAllConstraints { self.container.translatesAutoresizingMaskIntoConstraints = NO; self.progressBar.translatesAutoresizingMaskIntoConstraints = NO; self.progressLabel.translatesAutoresizingMaskIntoConstraints = NO; self.maskedProgressLabel.translatesAutoresizingMaskIntoConstraints = NO; self.mask.translatesAutoresizingMaskIntoConstraints = NO; id views = @{@"container": self.container, @"progressBar": self.progressBar, @"progressLabel": self.progressLabel, @"maskedProgressLabel": self.maskedProgressLabel, @"mask": self.mask}; // container constraint [self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-5-[container]-5-|" options:0 metrics:nil views:views]]; [self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-5-[container]-5-|" options:0 metrics:nil views:views]]; // progressBar constraint [self.container addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[progressBar]" options:0 metrics:nil views:views]]; progressBarWidthConstraint = [NSLayoutConstraint constraintWithItem:self.progressBar attribute:NSLayoutAttributeWidth relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeWidth multiplier:1.0 constant:0]; [self.container addConstraint:progressBarWidthConstraint]; [self.container addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|[progressBar]|" options:0 metrics:nil views:views]]; // progressLabel constraint [self.container addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[progressLabel]|" options:0 metrics:nil views:views]]; [self.container addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|[progressLabel]|" options:0 metrics:nil views:views]]; // maskedProgressLabel constraint [self.container addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[maskedProgressLabel]|" options:0 metrics:nil views:views]]; [self.container addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|[maskedProgressLabel]|" options:0 metrics:nil views:views]]; // mask constraint [self.container addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[mask]" options:0 metrics:nil views:views]]; [self.container addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|[mask]|" options:0 metrics:nil views:views]]; progressBarMaskWidthConstraint = [NSLayoutConstraint constraintWithItem:self.mask attribute:NSLayoutAttributeWidth relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeWidth multiplier:1.0 constant:0]; [self.container addConstraint:progressBarMaskWidthConstraint]; } -(void)setProgress:(CGFloat)progress { int percentage = progress * 100; NSString *strProgress = [[NSString alloc] initWithFormat:@"%d%%", percentage]; self.progressLabel.text = strProgress; self.maskedProgressLabel.text = strProgress; // ------------------------------------------------------------------ // subtracting 10 pixel for the |-5-[progressBar]-5-| padding in // the constraint for the progresBar // ------------------------------------------------------------------ progressBarWidthConstraint.constant = progress * (self.bounds.size.width - 10.0); progressBarMaskWidthConstraint.constant = progressBarWidthConstraint.constant; [self layoutIfNeeded]; [self updateMask]; } -(void)updateMask { // ------------------------------------------------------------------------ // Masking code taken from: // // https://stackoverflow.com/questions/11391058/simply-mask-a-uiview-with-a-rectangle // ------------------------------------------------------------------------ CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init]; CGRect maskRect = CGRectMake(0, 0, progressBarMaskWidthConstraint.constant, self.mask.bounds.size.height); CGPathRef path = CGPathCreateWithRect(maskRect, NULL); maskLayer.path = path; CGPathRelease(path); self.maskedProgressLabel.layer.mask = maskLayer; } @end
您可以使用两个UILabel轻松完成此操作，其中一个使用前面的文本颜色，另一个使用后面的文本颜色。 它们应该完全相互重叠。 然后，您可以缩小与计时器对应的顶部标签的宽度，并开始显示底部的标签。 这应该会给你你想要的效果。