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//

//  Created by Unmi Qiu on 8/11/11.

//  Copyright 2011 . All rights reserved.

//

#import <UIKit/UIKit.h>

#import "CorePlot-CocoaTouch.h"

@interface TestCorePlotViewController : UIViewController<CPTPlotDataSource> {

    NSMutableArray *dataArray;

}

@end

@implementation TestCorePlotViewController

#pragma mark - View lifecycle

- (void) viewDidAppear:(BOOL)animated {

    //初始化数组，并放入十个 0 － 20 间的随机数

    dataArray = [[NSMutableArray alloc] init];

    for(int i=0; i< 10; i++){

        [dataArray addObject:[NSNumber numberWithInt:rand()%20]];

    }

    CGRect frame = CGRectMake(10,10, 300,100);

    //图形要放在一个 CPTGraphHostingView 中，CPTGraphHostingView 继承自 UIView

    CPTGraphHostingView *hostView = [[CPTGraphHostingView alloc] initWithFrame:frame];

    //把 CPTGraphHostingView 加到你自己的 View 中

    [self.view addSubview:hostView];

    hostView.backgroundColor = [UIColor blueColor];

    //在 CPTGraph 中画图，这里的 CPTXYGraph 是个曲线图

    //要指定 CPTGraphHostingView 的 hostedGraph 属性来关联

    CPTXYGraph *graph = [[CPTXYGraph alloc] initWithFrame:hostView.frame];

    hostView.hostedGraph = graph;

    CPTScatterPlot *scatterPlot = [[CPTScatterPlot alloc] initWithFrame:graph.bounds];

    [graph addPlot:scatterPlot];

    scatterPlot.dataSource = self; //设定数据源，需应用 CPTPlotDataSource 协议

    //设置 PlotSpace，这里的 xRange 和 yRange 要理解好，它决定了点是否落在图形的可见区域

    //location 值表示坐标起始值，一般可以设置元素中的最小值

    //length 值表示从起始值上浮多少，一般可以用最大值减去最小值的结果

    //其实我倒觉得，CPTPlotRange:(NSRange) range 好理解些，可以表示值从 0 到 20

    CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *) scatterPlot.plotSpace;

    plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(0)

                                                    length:CPTDecimalFromFloat([dataArray count]-1)];

    plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(0)

                                                    length:CPTDecimalFromFloat(20)];

    //下面省去了坐标与线型及其他图形风格的代码

    [plotSpace release];

    [graph release];

    [hostView release];

}

//询问有多少个数据，在 CPTPlotDataSource 中声明的

- (NSUInteger) numberOfRecordsForPlot:(CPTPlot *)plot {

    return [dataArray count];

}

//询问一个个数据值，在 CPTPlotDataSource 中声明的

- (NSNumber *) numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index {

    if(fieldEnum == CPTScatterPlotFieldY){    //询问 Y 值时

        return [dataArray objectAtIndex:index];

    }else{                                    //询问 X 值时

        return [NSNumber numberWithInt:index];

    }

}

- (void) dealloc {

    [dataArray release];

    [super dealloc];

}

@end