将数据和带有委托的 CPTScatterPlot 对象封装到一个 class

Question

我正在尝试找到一种方法来将绘图数据和委托函数封装在一个 class 中。这将使根据我获取的数据集数量动态创建多个图变得更加简单。

为此，我创建了一个 class，其中包括 x、y 数据点和 CPTScatterPlot 对象，以及标准委托函数，这些函数现在是 class 访问内部函数的方法数据.

实例化对象时，思路是将数据和图形对象传递给它，构造函数使"self"成为数据源。

代码如下：

// DataScatterPlot.h

#import <Foundation/Foundation.h>
#import "CorePlot-CocoaTouch.h"

@interface DataScatterPlot : NSObject <CPTScatterPlotDataSource>

@property (nonatomic, strong) CPTScatterPlot *CPTScatterPlotObj;
@property (nonatomic, strong) NSMutableArray *x;
@property (nonatomic, strong) NSMutableArray *y;

- (id) initWithGraph: (CPTXYGraph*) graph DataX: (NSMutableArray*) x andDataY: (NSMutableArray*) y;

@end

// DataScatterPlot.m

#import "DataScatterPlot.h"

@implementation DataScatterPlot

-(id) initWithGraph: (CPTXYGraph *)graph DataX:(NSMutableArray *)dataX andDataY:(NSMutableArray *)dataY {
    self = [super init];
    if ( self != nil ) {
        self.CPTScatterPlotObj = [[CPTScatterPlot alloc] init];
        self.x = dataX;
        self.y = dataY;
        self.CPTScatterPlotObj.dataSource = (id<CPTScatterPlotDataSource>) self;
        [graph addPlot:self.CPTScatterPlotObj];         
    }
    return self;
}

// Delegate method that returns the number of points on the plot
-(NSUInteger)numberOfRecordsForPlot:(CPTPlot *)plot
{
    NSLog(@"The count is %lu", (unsigned long)[self.x count]);
    return [self.x count];
}

// Delegate method that returns a single X or Y value for a given plot.
-(NSNumber *)numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index
{
    // For Sigmoid
    NSNumber *dataX = [self.x objectAtIndex:index];
    NSNumber *dataY = [self.y objectAtIndex:index];

    // FieldEnum determines if we return an X or Y value.
    switch (fieldEnum) {
        case CPTScatterPlotFieldX:
        {
            return dataX;
        }
        case CPTScatterPlotFieldY: // Y-Axis
        {
            return dataY;
        }
        default:
            return [NSNumber numberWithFloat:0];
    }
}

@end

当我运行代码时，我得到一个 "unrecognized selector sent to instance" 错误，这似乎表明它正在寻找对象中不存在的方法。

我是不是做错了什么？

错误信息如下：

2015-10-09 12:02:09.743 SigmoidWithCustomDataClass[1192:10285] -[__NSDictionaryI numberOfRecordsForPlot:]: unrecognized selector sent to instance 0x7f9a2bda7fb0
2015-10-09 12:02:10.550 SigmoidWithCustomDataClass[1192:10285] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSDictionaryI numberOfRecordsForPlot:]: unrecognized selector sent to instance 0x7f9a2bda7fb0'
*** First throw call stack:
(
    0   CoreFoundation                      0x000000010f697c65 __exceptionPreprocess + 165
    1   libobjc.A.dylib                     0x000000010f330bb7 objc_exception_throw + 45
    2   CoreFoundation                      0x000000010f69f0ad -[NSObject(NSObject) doesNotRecognizeSelector:] + 205
    3   CoreFoundation                      0x000000010f5f513c ___forwarding___ + 988
    4   CoreFoundation                      0x000000010f5f4cd8 _CF_forwarding_prep_0 + 120
    5   SigmoidWithCustomDataClass          0x000000010eaae44b -[CPTPlot reloadData] + 94
    6   SigmoidWithCustomDataClass          0x000000010eaae289 -[CPTPlot drawInContext:] + 36
    7   QuartzCore                          0x000000010ec1b92b CABackingStoreUpdate_ + 2793
    8   QuartzCore                          0x000000010ed21933 ___ZN2CA5Layer8display_Ev_block_invoke + 59
    9   QuartzCore                          0x000000010ed217be _ZN2CA5Layer8display_Ev + 1478
    10  QuartzCore                          0x000000010ed164d9 _ZN2CA5Layer17display_if_neededEPNS_11TransactionE + 301
    11  QuartzCore                          0x000000010ed16561 _ZN2CA5Layer28layout_and_display_if_neededEPNS_11TransactionE + 35
    12  QuartzCore                          0x000000010ec8286e _ZN2CA7Context18commit_transactionEPNS_11TransactionE + 242
    13  QuartzCore                          0x000000010ec83a22 _ZN2CA11Transaction6commitEv + 462
    14  UIKit                               0x000000010fcd09ed -[UIApplication _reportMainSceneUpdateFinished:] + 44
    15  UIKit                               0x000000010fcd16b1 -[UIApplication _runWithMainScene:transitionContext:completion:] + 2648
    16  UIKit                               0x000000010fcd0095 -[UIApplication workspaceDidEndTransaction:] + 179
    17  FrontBoardServices                  0x0000000114bb75e5 __31-[FBSSerialQueue performAsync:]_block_invoke_2 + 21
    18  CoreFoundation                      0x000000010f5cb41c __CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 12
    19  CoreFoundation                      0x000000010f5c1165 __CFRunLoopDoBlocks + 341
    20  CoreFoundation                      0x000000010f5c0f25 __CFRunLoopRun + 2389
    21  CoreFoundation                      0x000000010f5c0366 CFRunLoopRunSpecific + 470
    22  UIKit                               0x000000010fccfb02 -[UIApplication _run] + 413
    23  UIKit                               0x000000010fcd28c0 UIApplicationMain + 1282
    24  SigmoidWithCustomDataClass          0x000000010eaad71f main + 111
    25  libdyld.dylib                       0x0000000112474145 start + 1
    26  ???                                 0x0000000000000001 0x0 + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)

Answer 1

绘图的数据源是字典。检查其余代码并确保您没有在任何地方重新分配数据源。

将数据和带有委托的 CPTScatterPlot 对象封装到一个 class

Encapsulating data and CPTScatterPlot object with delegates into one class

core-plot