使用核心图，如何将接触点转换为图空间？ [英] Using core-plot, how can you convert a touched point to the plot space?

问题描述

我有一个非常简单的图形，我想启用触摸功能，我的
第一部分正在工作：

I have a very simple graph that I want to enable touch on, I have the first part working:

plotSpace.delegate = self;

plotSpace.delegate = self;

以及方法：

-(BOOL)plotSpace:(CPPlotSpace *)space
shouldHandlePointingDeviceDownEvent:(id)event atPoint:(CGPoint)point
{
    NSLog(@"touched at: x: %f y: %f", point.x, point.y);
}

如何将点 point转换为图形的绘图空间？

How do I convert the point "point" to the plot space of my graph?

我可以看到这些方法，但是我不确定如何使用它们，doco，
虽然很大，但对它们的描述还不够好：）

I can see the methods, but Im unsure on how to use them, the doco, although large, doesnt really describe them well enough :)

非常感谢
标记

Thanks a lot Mark

推荐答案

承认，我忘记了这个问题，感谢史蒂夫的答复。

I have to admit, I forgot about this question, thanks for the reply Steve.

我也确实解决了它，这是我的实现（即扩展 CPXYGraph ）

I did get it solved too, here is my implementation (im extending CPXYGraph)

-(BOOL)plotSpace:(CPPlotSpace *)space shouldHandlePointingDeviceDownEvent:(id)event atPoint:(CGPoint)point {

    CPScatterPlot *plot = (CPScatterPlot*)[[self allPlots] objectAtIndex: 0];
    CGPoint pointInPlotArea = [plot convertPoint:point toLayer:plot];

    if ([plot containsPoint:pointInPlotArea]) {
        CPXYPlotSpace *plotSpace = (CPXYPlotSpace*)[self defaultPlotSpace];
        NSDecimal touchDataPoint[2];
        [plotSpace plotPoint:touchDataPoint forPlotAreaViewPoint:pointInPlotArea];
    }
}

touchDataPoint然后包含用户触摸过的坐标。

touchDataPoint then contains the coords that the user has touched.

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