iOS-UIView中的drawRect：平滑动画的建议

下面是我的代码，它工作正常，只是直线中移动直线的“动画”（guidelineOn）不平滑。drawRect每0.01秒调用一次

if (guideLineOn)
{
[self drawGuidanceLineAtPoint:CGPointMake((65+guideLineOffset)*scalingF, 98*scalingF) withAlpha:paramAlpha];
}

它有点滞后，有时会干扰用户输入。我如何解决这个问题？新的，所以开放的建议

提前感谢你的帮助

码头

- (void)drawRect:(CGRect)rect
{
scalingF = 1.0; // default : iPhone

if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)
{
    scalingF = IPAD_SCALING_FACTOR;
}

if (guideLineOn)
{
    [self drawGuidanceLineAtPoint:CGPointMake((65+guideLineOffset)*scalingF, 98*scalingF) withAlpha:paramAlpha];
}

// draw staff line
[self drawStaffLineFrom:CGPointMake(65*scalingF, 98*scalingF) toPoint:CGPointMake(420*scalingF, 98*scalingF)];
[self drawStaffLineFrom:CGPointMake(420*scalingF,108*scalingF) toPoint:CGPointMake(420*scalingF, 50*scalingF)];
[self drawStaffLineFrom:CGPointMake(415*scalingF,108*scalingF) toPoint:CGPointMake(415*scalingF, 50*scalingF)];

// cycle through all the static images to draw tbd
float offSet = 0.0;
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)
{
    offSet += 50.0; // to adjust the metronome down
}

if (metronomeImage)
{

    [metronomeImage drawInRect:CGRectMake(410.0f*scalingF, 195.0f*scalingF+offSet, metronomeImage.size.width*scalingF, metronomeImage.size.height*scalingF)];
}

if (circlesImage)
{
    [circlesImage drawInRect:CGRectMake(400.0f*scalingF, 255.0f*scalingF+offSet, circlesImage.size.width*scalingF, circlesImage.size.height*scalingF)];
}

for (Note * v in notesArray)
{
    UIImage * noteImage = [UIImage imageNamed: v.imageName];
    [noteImage drawInRect:CGRectMake(v.notePlacement.x*scalingF, v.notePlacement.y*scalingF, noteImage.size.width*scalingF, noteImage.size.height*scalingF)];
}

if (!clearDisplay) 
{
    // draw the arrows
    for (int i=0; i < arrowsToDrawArray.count; i++)
    {
        Arrow * arrowObj = [arrowsToDrawArray objectAtIndex:i];
        UIColor * colourOfArrow = [arrowObj colourOfArrow]; // colour determines whether right or wrong
        CGPoint p = [arrowObj arrowPlacement];
        p.x = p.x*scalingF;
        p.y = p.y*scalingF;

    //    CGPoint p = [val CGPointValue]; 
        [self drawRooftopAtTopPointof:p colour:colourOfArrow lineJoin:kCGLineJoinMiter];
    }

    // draw the ties
    for (int j=0; j < tiePointsArray.count; j++)
    {
        CGPointPair * tiePairToDraw = [tiePointsArray objectAtIndex:j];
        CGPoint firstPt = [tiePairToDraw firstPoint];
        firstPt.x = firstPt.x *scalingF;
        firstPt.y = firstPt.y *scalingF;

        CGPoint secondPt = [tiePairToDraw secondPoint];
        secondPt.x = secondPt.x *scalingF;
        secondPt.y = secondPt.y *scalingF;

        [self drawPseudoCurveFromPoint:firstPt toPoint:secondPt];
    }

    // bool perfect = true;
    // int noOfNotesHit = 0;

    // draw the tick/cross/arrow
    for (int k=0; k < answerObjArray.count; k++)
    {
        Answer * ansObj = [answerObjArray objectAtIndex:k];

        if (ansObj.hit)
        {
           // noOfNotesHit++;

            if (ansObj.earlyOrLate == -1) // early, draw right pointing arrow
            {
                UIImage * arrowImage = [UIImage imageNamed: @"arrowright.png"];
                [arrowImage drawInRect:CGRectMake((ansObj.xPosition-(0.5*arrowImage.size.width))*scalingF, 125*scalingF, arrowImage.size.width*scalingF, arrowImage.size.height*scalingF)];
               // perfect = false;
            }
            else if (ansObj.earlyOrLate == 1) // late, draw left pointing arrow
            {
                UIImage * arrowImage = [UIImage imageNamed: @"arrowleft.png"];
                [arrowImage drawInRect:CGRectMake((ansObj.xPosition-(0.5*arrowImage.size.width))*scalingF, 125*scalingF, arrowImage.size.width*scalingF, arrowImage.size.height*scalingF)];
                //perfect = false;
            }
            else // perfect!
            {
                // draw a tick
                UIImage * tickImage = [UIImage imageNamed: @"tick.png"];
                [tickImage drawInRect:CGRectMake((ansObj.xPosition-(0.5*tickImage.size.width))*scalingF, 125*scalingF, tickImage.size.width*scalingF, tickImage.size.height*scalingF)];
            }

        }
        else
        {
            // draw a cross
            UIImage * crossImage = [UIImage imageNamed: @"cross.png"];
            [crossImage drawInRect:CGRectMake((ansObj.xPosition-(0.5*crossImage.size.width))*scalingF, 125*scalingF, crossImage.size.width*scalingF, crossImage.size.height*scalingF)];
            //perfect = false;
        }

    }

}
else 
{
    // draw nothing
    clearDisplay = false; 
}

}

-（void）drawRect:（CGRect）rect
{
scalingF=1.0；//默认值：iPhone
if（UI\u USER\u INTERFACE\u IDIOM（）==UIUserInterfaceIdiomPad）
{
scalingF=IPAD\u缩放因子；
}
国际单项体育联合会（指南）
{
[self-DrawGuidanceLineEatPoint:CGPointMake（（65+导轨偏移）*缩放F，98*缩放F）带Alpha:paramAlpha]；
}
//划一条界线
[self-drawStaffLineFrom:CGPointMake（65*scalingF，98*scalingF）toPoint:CGPointMake（420*scalingF，98*scalingF）]；
[self-drawStaffLineFrom:CGPointMake（420*scalingF，108*scalingF）拓扑点：CGPointMake（420*scalingF，50*scalingF）]；
[self-drawStaffLineFrom:CGPointMake（415*scalingF，108*scalingF）拓扑点：CGPointMake（415*scalingF，50*scalingF）]；
//循环浏览所有静态图像以绘制tbd
浮动偏移=0.0；
if（UI\u USER\u INTERFACE\u IDIOM（）==UIUserInterfaceIdiomPad）
{
偏移量+=50.0；//向下调整节拍器
}
if（节拍器图像）
{
[metronomeImage drawInRect:CGRectMake（410.0f*缩放F，195.0f*缩放F+偏移，metronomeImage.size.width*缩放F，metronomeImage.size.height*缩放F）]；
}
if（圆形图像）
{
[circlesImage drawInRect:CGRectMake（400.0f*缩放F，255.0f*缩放F+偏移，circlesImage.size.width*缩放F，circlesImage.size.height*缩放F）]；
}
用于（notesArray中的Note*v）
{
UIImage*noteImage=[UIImage imageName:v.imageName]；
[noteImage drawInRect:CGRectMake（v.notePlacement.x*scalingF，v.notePlacement.y*scalingF，noteImage.size.width*scalingF，noteImage.size.height*scalingF）]；
}
如果（！clearDisplay）
{
//画箭头
对于（int i=0；i

以下是我为感兴趣的人提供的核心动画解决方案

- (void) animateRedLine: (float) alphaParam
{
[self.view addSubview:self.redlineImageView];
/* Start from top left corner */
[self.redlineImageView setFrame:CGRectMake(65.0f*scalingF,
                                          50.0f*scalingF,
                                          self.redlineImageView.image.size.width*scalingF,
                                          self.redlineImageView.image.size.height*scalingF*2)];

[self.redlineImageView setAlpha:alphaParam];

[UIView beginAnimations:@"redLineAnimation"
                context:( void *)self.redlineImageView];

/* 3 seconds animation */
[UIView setAnimationDuration:noOfBeatsInBar*timeInSecondsForOneBeat];
[UIView setAnimationCurve:UIViewAnimationCurveLinear];
/* Receive animation delegates */
[UIView setAnimationDelegate:self];

[UIView setAnimationDidStopSelector:
 @selector(imageViewDidStop:finished:context:)];

/* End at the bottom right corner */
[self.redlineImageView setFrame:CGRectMake((65.0f+LENGTH_OF_BAR)*scalingF,
                                          50.0f*scalingF,
                                          self.redlineImageView.image.size.width*scalingF,
                                          self.redlineImageView.image.size.height*scalingF*2)];

//[self.redlineImageView setAlpha:0.0f];

[UIView commitAnimations];
}

---

我很惊讶，你甚至可以达到每秒100次的速度！无论如何，这不是正确的技术使用-找到一种使用核心动画的方法，因为它将在GPU中完成，因此会像苹果的动画一样平滑。啊，我以前使用的是核心动画解决方案，没有意识到它会有所不同，谢谢你的信息！