我是新手,想在使用coreplot绘制的柱状图的x轴上显示NSdate(年份或月份或日),我已经查看了一些示例来绘制NSDate沿着x轴。但是我无法绘制...
请问有人可以提供绘制NSDate沿x轴的代码吗? 谢谢
我尝试了stackoverflow上的以下代码,但无法在x轴上显示标签。
请问有人可以提供绘制NSDate沿x轴的代码吗? 谢谢
我尝试了stackoverflow上的以下代码,但无法在x轴上显示标签。
// If you make sure your dates are calculated at noon, you shouldn't have to
// worry about daylight savings. If you use midnight, you will have to adjust
// for daylight savings time.
NSDate *refDate = [NSDate dateWithTimeIntervalSinceReferenceDate:31556926 * 10];
NSTimeInterval oneDay = 24 * 60 * 60;
// Invert graph view to compensate for iOS coordinates
//CGAffineTransform verticalFlip = CGAffineTransformMakeScale(1,-1);
// self.view.transform = verticalFlip;
// allocate the graph within the current view bounds
graph = [[CPTXYGraph alloc] initWithFrame: self.view.bounds];
// assign theme to graph
CPTTheme *theme = [CPTTheme themeNamed:kCPTDarkGradientTheme];
[graph applyTheme:theme];
// Setting the graph as our hosting layer
CPTGraphHostingView *hostingView = [[CPTGraphHostingView alloc] initWithFrame:self.view.bounds];
[self.view addSubview:hostingView];
hostingView.hostedGraph = graph;
graph.paddingLeft = 20.0;
graph.paddingTop = 20.0;
graph.paddingRight = 20.0;
graph.paddingBottom = 150.0;
// setup a plot space for the plot to live in
CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *)graph.defaultPlotSpace;
NSTimeInterval xLow = 0.0f;
// sets the range of x values
plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(xLow)
length:CPTDecimalFromFloat(oneDay*5.0f)];
// sets the range of y values
plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(0.0)
length:CPTDecimalFromFloat(5)];
// plotting style is set to line plots
CPTMutableLineStyle *lineStyle = [CPTMutableLineStyle lineStyle];
lineStyle.lineColor = [CPTColor blackColor];
lineStyle.lineWidth = 2.0f;
// X-axis parameters setting
CPTXYAxisSet *axisSet = (id)graph.axisSet;
axisSet.xAxis.majorIntervalLength = CPTDecimalFromFloat(oneDay);
axisSet.xAxis.minorTicksPerInterval = 0;
axisSet.xAxis.orthogonalCoordinateDecimal = CPTDecimalFromString(@"1"); //added for date, adjust x line
axisSet.xAxis.majorTickLineStyle = lineStyle;
axisSet.xAxis.minorTickLineStyle = lineStyle;
axisSet.xAxis.axisLineStyle = lineStyle;
axisSet.xAxis.minorTickLength = 5.0f;
axisSet.xAxis.majorTickLength = 7.0f;
axisSet.xAxis.labelOffset = 3.0f;
// added for date
NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease];
dateFormatter.dateStyle = kCFDateFormatterShortStyle;
CPTTimeFormatter *timeFormatter = [[[CPTTimeFormatter alloc] initWithDateFormatter:dateFormatter] autorelease];
timeFormatter.referenceDate = refDate;
axisSet.xAxis.labelFormatter = timeFormatter;
// Y-axis parameters setting
axisSet.yAxis.majorIntervalLength = CPTDecimalFromString(@"0.5");
axisSet.yAxis.minorTicksPerInterval = 2;
axisSet.yAxis.orthogonalCoordinateDecimal = CPTDecimalFromFloat(oneDay); // added for date, adjusts y line
axisSet.yAxis.majorTickLineStyle = lineStyle;
axisSet.yAxis.minorTickLineStyle = lineStyle;
axisSet.yAxis.axisLineStyle = lineStyle;
axisSet.yAxis.minorTickLength = 5.0f;
axisSet.yAxis.majorTickLength = 7.0f;
axisSet.yAxis.labelOffset = 3.0f;
// This actually performs the plotting
CPTScatterPlot *xSquaredPlot = [[[CPTScatterPlot alloc] init] autorelease];
CPTMutableLineStyle *dataLineStyle = [CPTMutableLineStyle lineStyle];
//xSquaredPlot.identifier = @"X Squared Plot";
xSquaredPlot.identifier = @"Date Plot";
dataLineStyle.lineWidth = 1.0f;
dataLineStyle.lineColor = [CPTColor redColor];
xSquaredPlot.dataLineStyle = dataLineStyle;
xSquaredPlot.dataSource = self;
CPTPlotSymbol *greenCirclePlotSymbol = [CPTPlotSymbol ellipsePlotSymbol];
greenCirclePlotSymbol.fill = [CPTFill fillWithColor:[CPTColor greenColor]];
greenCirclePlotSymbol.size = CGSizeMake(2.0, 2.0);
xSquaredPlot.plotSymbol = greenCirclePlotSymbol;
// add plot to graph
[graph addPlot:xSquaredPlot];
// Add some data
NSMutableArray *newData = [NSMutableArray array];
NSUInteger i;
for ( i = 0; i < 5; i++ ) {
NSTimeInterval x = oneDay*i;
id y = [NSDecimalNumber numberWithFloat:1.2*rand()/(float)RAND_MAX + 1.2];
[newData addObject:
[NSDictionary dictionaryWithObjectsAndKeys:
[NSDecimalNumber numberWithFloat:x], [NSNumber numberWithInt:CPTScatterPlotFieldX],
y, [NSNumber numberWithInt:CPTScatterPlotFieldY],
nil]];
NSLog(@"%@",newData);
}
plotData = [newData retain];
}
#pragma mark - Plot Data Source Methods
-(NSUInteger)numberOfRecordsForPlot:(CPTPlot *)plot
{
return plotData.count;
}
-(NSNumber *)numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex: (NSUInteger)index
{
NSDecimalNumber *num = [[plotData objectAtIndex:index] objectForKey:[NSNumber numberWithInt:fieldEnum]];
return num;
}