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Right now I've got a GA Gradient layer where I've set the colors but I'd like to set the color point to (instead of top center, to top left) and the bottom to (instead of bottom center to bottom right) just to change things up a bit. Thoughts? Below is the code that I've got so far...I included core animation because I'm animation between colors.

- (id)init {
    self = [super init];

    UIView *gradientView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.w, self.h)];
    [self addSubview:gradientView];
    [self sendSubviewToBack:gradientView];

    topColor = [UIColor colorWithRed:0.012 green:0.012 blue:0.012 alpha:1];
    bottomColor = [UIColor colorWithRed:1.000 green:0.765 blue:0.235 alpha:1];

    gradient = [CAGradientLayer layer];
    gradient.frame = gradientView.frame;
    gradient.colors = [NSArray arrayWithObjects:(id)topColor.CGColor, (id)bottomColor.CGColor, nil];
    gradient.locations = [NSArray arrayWithObjects:[NSNumber numberWithFloat:0.0f], [NSNumber numberWithFloat:0.7], nil];
    [gradientView.layer addSublayer:gradient];

    [self performSelector:@selector(animateColors) withObject:self afterDelay:2.0];
    currentColorCount = 1;
    return self;
}

On the right (What I've got) on the left (what I'd like)

On the right (What I've got) on the left (what I'd like)

4

1 回答 1

118

a的startPoint和endPoint属性CAGradientLayer在“单位坐标系”中定义。在单位坐标系中：

  • (0,0)对应于图层边界矩形的最小坐标，在 iOS 上是它的左上角，除非图层已经被转换；
  • (1,1)对应于图层边界矩形的最大坐标，在 iOS 上是其右下角，除非图层已被转换。

因此，按照您想要的方式排列渐变应该很简单：

gradient.startPoint = CGPoint.zero
gradient.endPoint = CGPoint(x: 1, y: 1)
于 2013-12-04T23:00:09.180 回答