Coreplot - 轴标签的坐标和大小

Question

我在x轴上使用日期标签，并希望使用自定义视图突出显示特定日期。我打算使用axis:labelWasSelected:，将annotationFrame移动到标签位置并在轴范围更改时滚动它（在plotSpacewillChangePlotRangeToForCoordinate:中移动注释）（simillar to core plot Framework - How to set custom UIView in CPTPlotSpaceAnnotation）

从plotSpacewillChangePlotRangeToForCoordinate调用时，如何获取标签的坐标？

编辑： 我已经成功实现了用户选择调用的移动注释：我保存_selectedLabel并在绘图范围更改时发送newFrame。这有两个问题：

1. 更改范围时延迟注释框架 - 请参阅电影：https://www.youtube.com/watch?v=R66ew6GAiJU&feature=youtu.be

2. 当带注释的标签离开屏幕时，_selectedLabel被遗忘＆＃34;。当回到屏幕时，可能会创建新标签，并且我对旧对象 - ＆gt;框架的_selectedLabel引用保持在x = 0（它离开屏幕的点）。也许在某种程度上可以获得特定标签的坐标（基于与dateToAnnotate的比较）？

   -(void)axis:(CPTAxis *)axis labelWasSelected:(CPTAxisLabel *)label {
           NSLog(@"labelWasSelected: %@",label);
           _selectedLabel = label;
           CGRect graphLabelFrame = [self adjustAnnotationFrameForLabel:_selectedLabel];
           [_delegate datesPlot:self didAnnotateFrame:graphLabelFrame animating:YES];
       }
   
   -(CPTPlotRange *)plotSpace:(CPTPlotSpace *)space willChangePlotRangeTo:(nonnull CPTPlotRange *)newRange forCoordinate:(CPTCoordinate)coordinate {
        CGRect graphLabelFrame = [self adjustAnnotationFrameForLabel:_selectedLabel];
       [_delegate datesPlot:self didAnnotateFrame:graphLabelFrame animating:NO];
   }
   

并在代表中：

-(void)datesPlot:(datesPlot*) plot didAnnotateFrame:(CGRect)frame animating:(BOOL)animating{
    if (animating) {
    [UIView animateWithDuration:0.3 animations:^{
        _annotationView.frame = [self.view convertRect:frame fromView:_datesHostingView];
    }];
    }
    else {
        _annotationView.frame = [self.view convertRect:frame fromView:_datesHostingView];
    }

    [_annotationView setNeedsLayout];
}

EDIT2： adjustAnnotation - 添加间距并将框架转换为图形坐标setNeedLayout由代理在转换为父视图坐标后调用。

-(CGRect)adjustAnnotationFrameForSelectedLabel {
    NSLog(@"selected Label:\n %@", _selectedLabel);
    float annotationMargin = 20;
    CGRect labelFrame = _selectedLabel.contentLayer.frame;
    NSLog(@"labelframe: x: %f, y: %f", labelFrame.origin.x, labelFrame.origin.y );
    //add margin for annotation to label's frame
    CGRect annotationFrame  = CGRectMake(labelFrame.origin.x-annotationMargin/2, labelFrame.origin.y-annotationMargin/2,
                                         labelFrame.size.width+annotationMargin, labelFrame.size.height+annotationMargin);
    // convert from plot area coordinates to graph (and hosting view) coordinates
    CGRect graphLabelFrame  = [self.graph convertRect:annotationFrame fromLayer:self.graph.plotAreaFrame.plotArea];
    NSLog(@"graphLabelFrame: x: %f, y: %f", graphLabelFrame.origin.x, graphLabelFrame.origin.y );
    return graphLabelFrame;

}

Answer 1

-axis:labelWasSelected:方法的第二个参数是轴标签。标签的contentLayer是实际显示标签的CALayer子类。使用内置坐标转换方法将frame的{​​{1}}和/或bounds转换为注释contentLayer的坐标空间。