iOS彩虹颜色数组

我正在设置一个arrays，在彩虹的颜色中有一个过渡。 现在我只是手动input数组中的颜色，但有太多的手动input…截至目前，我只是从0.25到0.5到0.75到1等等，直到我从红色到绿色到蓝色然后回来。 （见下面的代码）我怎么能让数组自动生成颜色超过0.25 – > 0.5 – > 0.75，但也许0.05 – > 0.10 – > 0.15 – > 0.20等等，…这里是我的数组：

rainbowColors = [[NSArray alloc] initWithObjects: [UIColor colorWithRed:1 green:0 blue:0 alpha:1], [UIColor colorWithRed:1 green:0.25 blue:0 alpha:1], [UIColor colorWithRed:1 green:0.5 blue:0 alpha:1], [UIColor colorWithRed:1 green:0.75 blue:0 alpha:1], [UIColor colorWithRed:1 green:1 blue:0 alpha:1], [UIColor colorWithRed:0.75 green:1 blue:0 alpha:1], [UIColor colorWithRed:0.5 green:1 blue:0 alpha:1], [UIColor colorWithRed:0.25 green:1 blue:0 alpha:1], [UIColor colorWithRed:0 green:1 blue:0 alpha:1], [UIColor colorWithRed:0 green:1 blue:0.25 alpha:1], [UIColor colorWithRed:0 green:1 blue:0.5 alpha:1], [UIColor colorWithRed:0 green:1 blue:0.75 alpha:1], [UIColor colorWithRed:0 green:1 blue:1 alpha:1], [UIColor colorWithRed:0 green:0.75 blue:1 alpha:1], [UIColor colorWithRed:0 green:0.5 blue:1 alpha:1], [UIColor colorWithRed:0 green:0.25 blue:1 alpha:1], [UIColor colorWithRed:0 green:0 blue:1 alpha:1], [UIColor colorWithRed:0.25 green:0 blue:1 alpha:1], [UIColor colorWithRed:0.5 green:0 blue:1 alpha:1], [UIColor colorWithRed:0.75 green:0 blue:1 alpha:1], [UIColor colorWithRed:1 green:0 blue:1 alpha:1], [UIColor colorWithRed:1 green:0 blue:0.75 alpha:1], [UIColor colorWithRed:1 green:0 blue:0.5 alpha:1], [UIColor colorWithRed:1 green:0 blue:0.25 alpha:1],nil]; 

Answer 1

很简单，使用-[UIColor colorWithHue:saturation:brightness:alpha:] ，如下所示：

 NSMutableArray *colors = [NSMutableArray array]; float INCREMENT = 0.05; for (float hue = 0.0; hue < 1.0; hue += INCREMENT) { UIColor *color = [UIColor colorWithHue:hue saturation:1.0 brightness:1.0 alpha:1.0]; [colors addObject:color]; } 

这样可以改变色调（或颜色），而不必改变屏幕上颜色的亮度，而这些颜色现在很可能不会保留。 写起来也简单得多，而且对于后来的读者来说更加清楚。

Answer 2

3个嵌套for循环和3个variablesr，g，b，每次发生循环时加0.25。