Question

我在iOS 7.1上使用Core Plot 2.0进行简单的X / Y散点图时遇到问题

以下情节代码：

CPTGraphHostingView* graphHostView;
CPTXYGraph* graph;
CPTScatterPlot* plot;
CPTXYPlotSpace* plotSpace;
DebugLog(@"Initializing GRAPH HOST VIEW");

graphHostView = [[CPTGraphHostingView alloc] initWithFrame:CGRectMake(10, 10, 300, 200)];
[self addSubview: graphHostView];

// Create a CPTGraph object and add to hostView
graph = [[CPTXYGraph alloc] initWithFrame:graphHostView.bounds];
graphHostView.hostedGraph = graph;

// Get the (default) plotspace from the graph so we can set its x/y ranges
CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *) graph.defaultPlotSpace;

// Note that these CPTPlotRange are defined by START and LENGTH (not START and END) !!
[plotSpace setYRange: [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat( 0 ) length:CPTDecimalFromFloat( 20000 )]];
[plotSpace setXRange: [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat( 0 ) length:CPTDecimalFromFloat( 6 )]];

// Create the plot (we do not define actual x/y values yet, these will be supplied by the datasource...)
plot = [[CPTScatterPlot alloc] initWithFrame:CGRectZero];

plot.dataSource = dataSource;

[graph addPlot:plot toPlotSpace:graph.defaultPlotSpace];

只需60秒即可完成100％CPU使用率的磨削，并可稳定地分配高达300 MB的RAM。怎么可能？该图表托管在“父”UIView中。

之前我使用过Core Plot，虽然看起来很慢，但这显然是完全无法接受的！可能是什么原因造成的？

Answer 1

我在更新图表时使用dispatch_async解决了这个问题。例如，在我使用的代码中：

dispatch_async(dispatch_get_main_queue(), ^{
    [self setupGraph];
});

我希望这会有所帮助。

Core Plot在iOS上速度极慢？

1 个答案: