ios - CorePlot 多个散点图内存消耗巨大

Question

我在使用 CorePlot 时遇到了一些问题。我尝试将多个散点图绘制到一张图中。这按预期工作，但当我开始滚动或缩放图形时，整个应用程序将其内存使用量增加到 900MB 并崩溃。我想我必须做一些对象释放，但我不知道怎么做。基本上我用不同的绘图标识符绘制每一行，并将相应的数据放入数据源。

这是我得到的:(在这个示例代码中，为了测试目的，我只是用静态值减少了 ax 范围。)

- (void)setupGraph {
// Create graph from theme
self.graph = [[CPTXYGraph alloc] initWithFrame:self.scatterPlotView.bounds];
self.graph.plotAreaFrame.masksToBorder = NO;
self.scatterPlotView.hostedGraph = self.graph;

CPTTheme *theme = [CPTTheme themeNamed:kCPTPlainBlackTheme];
[self.graph applyTheme:theme];

self.graph.paddingLeft   = 0.0;
self.graph.paddingTop    = 0.0;
self.graph.paddingRight  = 0.0;
self.graph.paddingBottom = 0.0;


// Setup plot space
CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *)self.graph.defaultPlotSpace;

plotSpace.allowsUserInteraction = YES;

plotSpace.delegate = self;

plotSpace.globalXRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromDouble(0) length:CPTDecimalFromDouble(30)];
plotSpace.globalYRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromDouble(0) length:CPTDecimalFromDouble(15)];

plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromDouble(0) length:CPTDecimalFromDouble(10)];
plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromDouble(0) length:CPTDecimalFromDouble(15)];

CPTXYAxisSet *axisSet = (CPTXYAxisSet *)self.graph.axisSet;
CPTXYAxis *x = axisSet.xAxis;
CPTXYAxis *y = axisSet.yAxis;
x.labelingPolicy = CPTAxisLabelingPolicyNone;
y.labelingPolicy = CPTAxisLabelingPolicyNone;
}

此方法加载我的数据并绘制散点图

- (void)loadSignals {


//Data loading logic goes here nothing special just one array for each plot

for (Signal *sig in [signals allValues]) {
    [self constructScatterPlot:sig.name];
}
}];

这是绘图发生的地方:

- (void)constructScatterPlot:(NSString *)identifier {    
    CPTScatterPlot *dataSourceLinePlot = [[CPTScatterPlot alloc] init];

   CPTMutableLineStyle *lineStyle = [dataSourceLinePlot.dataLineStyle mutableCopy];

    CPTScatterPlot *boundLinePlot = [[CPTScatterPlot alloc] init];
    boundLinePlot.identifier = identifier;

    lineStyle            = [boundLinePlot.dataLineStyle mutableCopy];
    lineStyle.miterLimit = 1.0;
    lineStyle.lineWidth  = 1.0;
    lineStyle.lineColor  = [CPTColor redColor];
    boundLinePlot.dataLineStyle = lineStyle;

    boundLinePlot.dataSource     = self;
    boundLinePlot.cachePrecision = CPTPlotCachePrecisionDouble;
    boundLinePlot.interpolation  = CPTScatterPlotInterpolationStepped;
    [self.graph addPlot:boundLinePlot];
}

...这是数据源获取其值的地方:

-(NSNumber *)numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index
{
NSString *plotIdent = (NSString *) plot.identifier;

     if (![plotIdent isEqualToString:self.currentIdent]) {
        self.countPlot++;
        self.currentIdent = plotIdent;
    }

Signal *newSig = [self.signals objectForKey:plotIdent];
    Value * newValue = [newSig valueAtTime:index];
NSNumber *number = [NSNumber numberWithInteger:[newValue.value integerValue]];

    if ( fieldEnum == CPTScatterPlotFieldY ) {

        return number;
    }
    if ( fieldEnum == CPTScatterPlotFieldX ) {
        return [NSNumber numberWithInteger:index];
    }
    return nil;
}

所以首先我想知道这是否是将多个图(在我的例子中最多 40 个)绘制到一个图中的正确方法？如果是这样，我可以做些什么来优化我的情节表现？

输出应该是这样的:

Answer 1

我发现了这个用途

“尝试在托管 View 上将 collapsesLayers 设置为 YES”

Application get stuck when drawing nearly 40 Scatter Plots using Core Plot in IPad