我是corePlot的新手，当我们在UIPickerView中选择一个特定的行时，我无法从json动态绘制图形（Line）。 在这里，
Line graph with x-axis: Time as 02,03,04,.....
y-axis: temperature as 10,20,30,.....
UIPickerView consists of Date(s). for eg: we have 3 rows :
06-03-2015, 07-03-2015, 08-03-2015
现在如果我们在UIPickerView中选择任何特定的行，我必须显示折线图。我已经完成了静态数据，但现在我遇到了动态数据的问题。
-(void)initialisePlot
{
// Start with some simple sanity checks before we kick off
if ( (self.hostingView == nil) || (self.graphData == nil) ) {
NSLog(@"TUTSimpleScatterPlot: Cannot initialise plot without hosting view or data.");
return;
}
if ( self.graph != nil ) {
NSLog(@"TUTSimpleScatterPlot: Graph object already exists.");
return;
}
// Create a graph object which we will use to host just one scatter plot.
CGRect frame = [self.hostingView bounds];
//CGRect frame = [self.hostingView bounds];
//CGRect frame = [self.hostingView frame];
self.graph = [[CPTXYGraph alloc] initWithFrame:frame] ;
//self.hostingView=[[CPTGraphHostingView alloc]initWithFrame:CGRectMake(0.0, 0.0, 900.0, 420.0)];
//self.graph = [[CPTXYGraph alloc] initWithFrame:self.hostingView.bounds];
// Add some padding to the graph, with more at the bottom for axis labels.
self.graph.plotAreaFrame.paddingTop = 20.0f;
self.graph.plotAreaFrame.paddingRight = 10.0f;
self.graph.plotAreaFrame.paddingBottom = 50.0f;
self.graph.plotAreaFrame.paddingLeft = 60.0f;
// Tie the graph we've created with the hosting view.
self.hostingView.hostedGraph = self.graph;
// If you want to use one of the default themes - apply that here.
[self.graph applyTheme:[CPTTheme themeNamed:kCPTDarkGradientTheme]];
// Create a line style that we will apply to the axis and data line.
CPTMutableLineStyle *lineStyle = [CPTMutableLineStyle lineStyle];
lineStyle.lineColor = [CPTColor whiteColor];
lineStyle.lineWidth = 2.0f;
// Create a text style that we will use for the axis labels.
CPTMutableTextStyle *textStyle = [CPTMutableTextStyle textStyle];
textStyle.fontName = @"Helvetica";
textStyle.fontSize = 14;
textStyle.color = [CPTColor whiteColor];
// Create the plot symbol we're going to use.
CPTPlotSymbol *plotSymbol = [CPTPlotSymbol crossPlotSymbol];
plotSymbol.lineStyle = lineStyle;
plotSymbol.size = CGSizeMake(8.0, 8.0);
// Setup some floats that represent the min/max values on our axis.
int xAxisMin = 0;
int xAxisMax = 20;
float yAxisMin = 0;
float yAxisMax = 50;
// We modify the graph's plot space to setup the axis' min / max values.
CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *)self.graph.defaultPlotSpace;
plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromInt(xAxisMin) length:CPTDecimalFromInt(xAxisMax-xAxisMin)];
plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(yAxisMin) length:CPTDecimalFromFloat(yAxisMax - yAxisMin)];
// Modify the graph's axis with a label, line style, etc.
CPTXYAxisSet *axisSet = (CPTXYAxisSet *)self.graph.axisSet;
axisSet.xAxis.title = @"Time";
axisSet.xAxis.titleTextStyle = textStyle;
axisSet.xAxis.titleOffset = 20;
axisSet.xAxis.axisLineStyle = lineStyle;
axisSet.xAxis.majorTickLineStyle = lineStyle;
axisSet.xAxis.minorTickLineStyle = lineStyle;
axisSet.xAxis.labelTextStyle = textStyle;
axisSet.xAxis.labelOffset = 3;
axisSet.xAxis.majorIntervalLength = CPTDecimalFromInt(2);
axisSet.xAxis.minorTicksPerInterval = 1;
axisSet.xAxis.minorTickLength = 5;
axisSet.xAxis.majorTickLength = 7;
axisSet.yAxis.title = @"Temperature";
axisSet.yAxis.titleTextStyle = textStyle;
axisSet.yAxis.titleOffset = 40.0f;
axisSet.yAxis.axisLineStyle = lineStyle;
axisSet.yAxis.majorTickLineStyle = lineStyle;
axisSet.yAxis.minorTickLineStyle = lineStyle;
axisSet.yAxis.labelTextStyle = textStyle;
axisSet.yAxis.labelOffset = 3.0f;
axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(10.0f);
axisSet.yAxis.minorTicksPerInterval = 1;
axisSet.yAxis.minorTickLength = 5.0f;
axisSet.yAxis.majorTickLength = 7.0f;
// Add a plot to our graph and axis. We give it an identifier so that we
// could add multiple plots (data lines) to the same graph if necessary.
CPTScatterPlot *plot = [[CPTScatterPlot alloc] init] ;
plot.dataSource = self;
plot.identifier = @"mainplot";
plot.dataLineStyle = lineStyle;
plot.plotSymbol = plotSymbol;
[self.graph addPlot:plot];
}
// Delegate method that returns the number of points on the plot
-(NSUInteger)numberOfRecordsForPlot:(CPTPlot *)plot
{
if ( [plot.identifier isEqual:@"mainplot"] )
{
return [self.graphData count];
}
return 0;
}
// Delegate method that returns a single X or Y value for a given plot.
-(NSNumber *)numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index
{
if ( [plot.identifier isEqual:@"mainplot"] )
{
NSValue *value = [self.graphData objectAtIndex:index];
CGPoint point = [value CGPointValue];
// FieldEnum determines if we return an X or Y value.
if ( fieldEnum == CPTScatterPlotFieldX )
{
return [NSNumber numberWithInt:point.x];
}
else // Y-Axis
{
return [NSNumber numberWithFloat:point.y];
}
}
return [NSNumber numberWithFloat:0];
}
在viewDidLoad中，我按如下方式调用此方法：
pickerData = [[NSArray alloc] initWithObjects：@＆＃34; 28-02-2015＆＃34;，@＆＃34; 01-03-2015＆＃34;，@＆＃34; 02-03-2015＆ ＃34;，@＆＃34; 03-03-2015＆＃34;，@＆＃34; 04-03-2015＆＃34;，nil]; NSMutableArray * data1 = [NSMutableArray array]; [data1 addObject：[NSValue valueWithCGPoint：CGPointMake（0,0）]];
self.scatterPlot = [[TUTSimpleScatterPlot alloc] initWithHostingView:_graphHostingView andData:data1];
[self.scatterPlot initialisePlot];
pickerView数据源和委托方法如下：
#pragma mark PickerView DataSource
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
{
return 1;
}
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{
return pickerData.count;
}
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
{
return pickerData[row];
}
#pragma mark -
#pragma mark PickerView Delegate
-(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{
//PickerModal *pModal=[picDataArray objectAtIndex:row];
pickObj=[picDataArray objectAtIndex:row];
//result=[NSString stringWithFormat:@"%@",pickObj.picDate];
NSLog(@"time :%@",pickObj.picTime);
NSLog(@"temp :%@",pickObj.picTemperature);
for (int i=0; i<50; i++) {
int selectedRow=[self.myPickerView selectedRowInComponent:0];
if ((selectedRow=i)) {
NSMutableArray *data1 = [NSMutableArray array];
[data1 addObject:[NSValue valueWithCGPoint:CGPointMake([pickObj.picTime floatValue], [pickObj.picTemperature floatValue])]];
NSMutableArray *arr=[[NSMutableArray alloc]initWithArray:data1];
self.scatterPlot = [[TUTSimpleScatterPlot alloc] initWithHostingView:_graphHostingView andData:arr];
[self.scatterPlot initialisePlot];
}
}
[pickerView reloadComponent:0];
}
我将json数据解析为：
-(void)retrieveData{
NSString *sensorTagID=@"UIUIA6767672345678910987654321";
NSMutableString *globalUrlString=[NSMutableString stringWithString:@"url"];
[globalUrlString appendString:[NSString stringWithFormat:@"?SensorTagID=%@",sensorTagID]];
NSLog(@"url string:%@",globalUrlString);
NSURL *url=[NSURL URLWithString:globalUrlString];
NSMutableURLRequest *globalRequest=[NSMutableURLRequest requestWithURL:[url standardizedURL]];
[globalRequest setHTTPMethod:@"GET"];
NSError *error = nil;
NSURLResponse *theResponse = [[NSURLResponse alloc]init];
//connecting to the server
NSData *data = [NSURLConnection sendSynchronousRequest:globalRequest returningResponse:&theResponse error:&error];
//NSData *data=[NSData dataWithContentsOfURL:url];
json=[NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:nil];
picDataArray=[[NSMutableArray alloc]init];
for (int i=0; i<json.count; i++) {
pickDate=[[json objectAtIndex:i]valueForKey:@"Date"];
NSLog(@"date %@",pickDate);
NSArray *getEvents=[[json objectAtIndex:i]valueForKey:@"OnDateSensorValues"];
for (NSDictionary *eventsObj in getEvents) {
pickHumidity=eventsObj[@"Humidity"];
//NSLog(@"humidity %@",pickHumidity);
pickLocationHumidity=eventsObj[@"LocationHumidity"];
//NSLog(@"locHumidity %@",pickLocationHumidity);
pickLocationTemperature=eventsObj[@"LocationTemperature"];
//NSLog(@"locTemp %@",pickLocationTemperature);
pickTemperature=eventsObj[@"Temperature"];
NSLog(@"temp %@",pickTemperature);
pickTime=eventsObj[@"Time"];
NSLog(@"time %@",pickTime);
}
pickObj=[[PickerModal alloc]initWithPicDate:pickDate andPicHumidity:pickHumidity andPicLocationHumidity:pickLocationHumidity andPicLocationTemperature:pickLocationTemperature andPicTemperature:pickTemperature andPicTime:pickTime];
[picDataArray addObject:pickObj];
}
[self.myPickerView reloadComponent:0];
}
json输出如下：
[
{
"Date": "2015-02-26",
"OnDateSensorValues": [
{
"Humidity": "49",
"LocationHumidity": "49",
"LocationTemperature": "45",
"Temperature": "45",
"Time": "10"
},
{
"Humidity": "48",
"LocationHumidity": "48",
"LocationTemperature": "44",
"Temperature": "44",
"Time": "11"
},
{
"Humidity": "47",
"LocationHumidity": "47",
"LocationTemperature": "43",
"Temperature": "43",
"Time": "12"
},
{
"Humidity": "46",
"LocationHumidity": "46",
"LocationTemperature": "42",
"Temperature": "42",
"Time": "13"
},
{
"Humidity": "45",
"LocationHumidity": "45",
"LocationTemperature": "41",
"Temperature": "41",
"Time": "14"
}
]
},
{
"Date": "2015-02-27",
"OnDateSensorValues": [
{
"Humidity": "29",
"LocationHumidity": "29",
"LocationTemperature": "25",
"Temperature": "25",
"Time": "6"
},
{
"Humidity": "28",
"LocationHumidity": "28",
"LocationTemperature": "24",
"Temperature": "24",
"Time": "7"
},
{
"Humidity": "27",
"LocationHumidity": "27",
"LocationTemperature": "23",
"Temperature": "23",
"Time": "8"
},
{
"Humidity": "26",
"LocationHumidity": "26",
"LocationTemperature": "22",
"Temperature": "22",
"Time": "9"
},
{
"Humidity": "25",
"LocationHumidity": "25",
"LocationTemperature": "21",
"Temperature": "21",
"Time": "10"
}
]
},
{
"Date": "2015-02-28",
"OnDateSensorValues": [
{
"Humidity": "31",
"LocationHumidity": "31",
"LocationTemperature": "35",
"Temperature": "35",
"Time": "22"
},
{
"Humidity": "32",
"LocationHumidity": "32",
"LocationTemperature": "36",
"Temperature": "36",
"Time": "21"
},
{
"Humidity": "33",
"LocationHumidity": "33",
"LocationTemperature": "37",
"Temperature": "37",
"Time": "20"
},
{
"Humidity": "34",
"LocationHumidity": "34",
"LocationTemperature": "38",
"Temperature": "38",
"Time": "19"
},
{
"Humidity": "35",
"LocationHumidity": "35",
"LocationTemperature": "39",
"Temperature": "39",
"Time": "18"
}
]
},
{
"Date": "2015-03-01",
"OnDateSensorValues": [
{
"Humidity": "12",
"LocationHumidity": "12",
"LocationTemperature": "16",
"Temperature": "16",
"Time": "2"
},
{
"Humidity": "13",
"LocationHumidity": "13",
"LocationTemperature": "17",
"Temperature": "17",
"Time": "1"
},
{
"Humidity": "14",
"LocationHumidity": "14",
"LocationTemperature": "18",
"Temperature": "18",
"Time": "2"
},
{
"Humidity": "15",
"LocationHumidity": "15",
"LocationTemperature": "19",
"Temperature": "19",
"Time": "3"
},
{
"Humidity": "16",
"LocationHumidity": "16",
"LocationTemperature": "20",
"Temperature": "20",
"Time": "4"
}
]
},
{
"Date": "2015-03-02",
"OnDateSensorValues": [
{
"Humidity": "32",
"LocationHumidity": "32",
"LocationTemperature": "36",
"Temperature": "36",
"Time": "20"
},
{
"Humidity": "33",
"LocationHumidity": "33",
"LocationTemperature": "37",
"Temperature": "37",
"Time": "21"
},
{
"Humidity": "34",
"LocationHumidity": "34",
"LocationTemperature": "38",
"Temperature": "38",
"Time": "22"
},
{
"Humidity": "35",
"LocationHumidity": "35",
"LocationTemperature": "39",
"Temperature": "39",
"Time": "23"
},
{
"Humidity": "36",
"LocationHumidity": "36",
"LocationTemperature": "40",
"Temperature": "40",
"Time": "24"
}
]
}
]
从这里我想采取临时值，时间值并在图表上显示。但我能够在图表上只绘制一个点。如何在图表上获得所有时间和临时值？....请帮助我，因为我从1周起就在努力解决这个问题。