我在使用CorePlot时遇到了一些问题。我试图将多个散点图绘制到一个图表中。虽然预期结果正确,但是当我开始滚动或缩放图表时,整个应用程序的内存使用量增加到900MB并崩溃了。我认为我需要释放一些对象,但我不知道怎么做。基本上,我使用不同的绘图标识符来绘制每条线,并将相应的数据放入数据源中。
这是绘图发生的地方:
这是我的代码:(在这个示例代码中,我只是为了测试目的而使用静态值减少了轴范围。)
- (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;
}
这个方法会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];
}
这就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;
}
首先,我想知道这是否是在一个图形中绘制多个图表的正确方式(在我的情况下最多有40个)?如果是这样,我应该如何优化我的绘图性能?
输出应该像这样: