我希望每次加载Navbar时都会使用不同的颜色。我在viewDidApear中放置了以下代码:
CGFloat hue = ( arc4random() % 256 / 256.0 ); // 0.0 to 1.0
CGFloat saturation = ( arc4random() % 128 / 256.0 ) + 0.5; // 0.5 to 1.0, away from white
CGFloat brightness = ( arc4random() % 128 / 256.0 ) + 0.5; // 0.5 to 1.0, away from black
UIColor *color = [UIColor colorWithHue:hue saturation:saturation brightness:brightness alpha:1];
self.navigationBar.barTintColor = color;
问题是颜色范围太宽。
我希望它只选择您在此照片中看到的颜色:
是否可以使用此代码? +如果不是,我将如何创建一个从我定义的几个中选择随机颜色的相似颜色。
谢谢你的帮助。
答案 0 :(得分:4)
这是使用您的确切颜色的复制/粘贴解决方案。
// Declare somewhere in your code
typedef struct _Color {
CGFloat red, green, blue;
} Color;
static Color _colors[12] = {
{237, 230, 4}, // Yellow just to the left of center
{158, 209, 16}, // Next color clockwise (green)
{80, 181, 23},
{23, 144, 103},
{71, 110, 175},
{159, 73, 172},
{204, 66, 162},
{255, 59, 167},
{255, 88, 0},
{255, 129, 0},
{254, 172, 0},
{255, 204, 0}
};
- (UIColor *)randomColor {
Color randomColor = _colors[arc4random_uniform(12)];
return [UIColor colorWithRed:(randomColor.red / 255.0f) green:(randomColor.green / 255.0f) blue:(randomColor.blue / 255.0f) alpha:1.0f];
}
注意:您应该使用arc4random_uniform()
代替arc4random()
来避免模偏差(尽管在这种情况下不是那么重要)。
答案 1 :(得分:1)
UIColor
以下是此代码:
-(UIColor *)randomColor
{
CGFloat hue = ( arc4random() % 256 / 256.0 );
CGFloat saturation = ( arc4random() % 128 / 256.0 ) + 0.5;
CGFloat brightness = ( arc4random() % 128 / 256.0 ) + 0.5;
UIColor *color = [UIColor colorWithHue:hue saturation:saturation brightness:brightness alpha:1];
return color;
}
答案 2 :(得分:0)
这就是诀窍:
NSArray *hues = @[ @76, @98, @160, @217, @292, @318, @327, @21, @30, @41, @48, @58 ];
NSNumber *hue = hues[arc4random_uniform(hues.count)];
UIColor *color = [UIColor colorWithHue:[hue doubleValue] / 360.0 saturation:1.0 brightness:1.0 alpha:1.0];
谢谢@Rmaddy