在Core plot iOS中以散点图符号形式显示散射图上的图像 [英] Showing images on Scattering Graph as plot symbols in Core plot iOS

问题描述

我有要求在散射图中的图形符号处显示图像。现在我正在使用CPTPlotSymbol在图上绘制符号。但我所能得到的只是预定义的对象。例如。 ellipsePlotSymbol，dashPlotSymbol，trianglePlotSymbol。

但是我需要绘制一张图片。

你能帮我吗？实现这一点。

解决方案

尝试了一下后得到了答案。

首先，我构建了一个自定义CPTLayer，并在其中使用该图像进行填充。
$ b CustomImageForScatterPlot.h文件

  #importCPTLayer.h
 
 
 @interface CustomImageForScatterPlot：CPTLayer 
 {
 UIImage * _image; 
 
 
  - （id）initWithImage：（UIImage *）image; 
 
 @end 
  

CustomImageForScatterPlot.m文件

  #importCustomImageForScatterPlot.h
 #importCPTLayer.h
 
 @implementation CustomImageForScatterPlot 
 
  - （void）dealloc {
 
 [_image release]; 
 [super dealloc]; 
 
  - （id）initWithImage：（UIImage *）image {
 
 CGRect f = CGRectMake（0，0，image.size.width，image.size.height） ; 
 
 if（self = [super initWithFrame：f]）{
 
 _image = [image retain]; 
} 
 
返回自我; 
 
 
 $ b  - （void）drawInContext：（CGContextRef）ctx {
 
 CGContextDrawImage（ctx，self.bounds，_image.CGImage）; 
 
 
 @end 
  

现在，在散点图（CPTLayer *）dataLabelForPlot：（CPTPlot *）plot recordIndex图表文件，我用下面的委托方法返回图像

   - ：（NSUInteger）index 
 {
 CustomImageForScatterPlot * layer = [[CustomImageForScatterPlot alloc] initWithImage：[UIImage imageNamed：@dots.png]]; 
 layer.frame = CGRectMake（2，0，34，6）; 
 
返回图层; 
} 
  

ENJOY CODING ....：）

I have a requirement of showing images at the plot symbols in my scattering Graph. Right now I am using CPTPlotSymbol to plot symbols on the graph. But all I can get with it are the predefined objects. Eg. ellipsePlotSymbol, dashPlotSymbol, trianglePlotSymbol.

But I need to plot an image instead.

Could you help me in acheiving this. Thanks a lot.

解决方案

Got the answer after trying a bit.

First of all, I built a Custom CPTLayer and inside it used the image to be filled.

CustomImageForScatterPlot.h file

 #import "CPTLayer.h"


 @interface CustomImageForScatterPlot : CPTLayer
 {    
     UIImage *_image;

 }
 -(id)initWithImage:(UIImage *)image;

 @end

CustomImageForScatterPlot.m file

#import "CustomImageForScatterPlot.h"
#import "CPTLayer.h"

@implementation CustomImageForScatterPlot

-(void)dealloc{

    [_image release];
    [super dealloc];
}
-(id)initWithImage:(UIImage *)image{

    CGRect f = CGRectMake(0, 0, image.size.width, image.size.height);

    if (self = [super initWithFrame:f]) {

        _image = [image retain];
    }

    return self;

}

-(void)drawInContext:(CGContextRef)ctx{

    CGContextDrawImage(ctx, self.bounds, _image.CGImage);

}
@end

NOW, in the Scatter plot graph file, I used the following delegate method to return the images

- (CPTLayer *)dataLabelForPlot:(CPTPlot *)plot recordIndex:(NSUInteger)index
{       
     CustomImageForScatterPlot* layer = [[CustomImageForScatterPlot alloc] initWithImage:[UIImage imageNamed:@"dots.png"]];
     layer.frame = CGRectMake(2, 0, 34, 6);

     return layer;        
}

ENJOY CODING.... :)

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