UIViewController crashing after being called the 2nd time - ios

Question

This probably has a really simple fix, but I have a UITableViewController that calls a UIViewController in a normal list/detail configuration.
Since I added 2 subviews to the detail viewcontroller the app has been crashing on the second time I display the detail view controller.
I do lots of setup etc. when the view is loaded, but I have gone through and I can't find anything that has been set to null etc. None of the initialising functions crash the app. It's only once they are done that the app falls over. I assume the detail view controller is going through the same initialization each time...
Has anyone encountered this before?
Here is where the detail view controller is called:
-(void) prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
/***************************************************************************************
The detail view is just sent the tank object for the selected tank. The detail view
loads the labels and gauge with the appropriate information
***************************************************************************************/
self.detailViewController = [[tankDetailViewController alloc] init];
self.detailViewController = segue.destinationViewController;
[segue.destinationViewController setTankToShow:self.selectedTank];
}
and the following is the code for the detailviewcontroller:
#interface tankDetailViewController () <iTanksV2ListViewControllerDelegate>
//#property (nonatomic, strong) tankReleasedProductListTVCViewController* releasedProductList;
#property (weak, nonatomic) IBOutlet NSLayoutConstraint *tankGaugeHeightConstraint;
#property (weak, nonatomic) IBOutlet UIView *tankDetailView;
#property (weak, nonatomic) IBOutlet UIView *tankTrendView;
#property (nonatomic, strong) CPTGraphHostingView* hostView;
#property (strong, nonatomic) CPTGraph* graph;
#property BOOL isFirstValue;
#property double startValue;
#property double lastValue;
#end
#implementation tankDetailViewController
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
/*************************************************************************************
All we need to do here, is to display all the information from the tank object in the
labels in the view.
The only thing of note is that we convert the volumes to doubles, and then use them to
calculate the percentFilled property of the tankGauge object.
************************************************************************************/
[super viewDidLoad];
self.isFirstValue = YES;
self.tankNumberLabel.text = [#"T" stringByAppendingString: self.tankToShow.tankNumber];
self.tankAvailableProductLabel.text = self.tankToShow.tankPumpableVolume;
self.tankProductLabel.text = self.tankToShow.tankProduct.name;
self.tankMaxVolumeLabel.text = self.tankToShow.tankMaxVolume;
self.tankGaugeHeightConstraint.constant = ([self.tankToShow.tankTotalVolume doubleValue]/[self.tankToShow.tankMaxVolume doubleValue]) * self.tankGaugeScaleView.frame.size.height;
self.tankTotalVolumeLabel.text = self.tankToShow.tankTotalVolume;
self.tankProductCode.text = self.tankToShow.tankProduct.code;
self.tankStatusLabel.text = self.tankToShow.tankStatus;
if([self.tankToShow.tankStatus isEqualToString:#"Process"])
{
[self.tankStatusLED setImage:[UIImage imageNamed:#"red_btn.png"] forState:UIControlStateNormal];
}
else if([self.tankToShow.tankStatus isEqualToString:#"Release"])
{
[self.tankStatusLED setImage:[UIImage imageNamed:#"green_btn.png"] forState:UIControlStateNormal];
}
else if([self.tankToShow.tankStatus isEqualToString:#"For Test"])
{
[self.tankStatusLED setImage:[UIImage imageNamed:#"amber_btn.png"] forState:UIControlStateNormal];
} else
{
[self.tankStatusLED setImage:[UIImage imageNamed:#"grey_btn.png"] forState:UIControlStateNormal];
}
[self.view bringSubviewToFront:self.tankDetailView];
self.graphData = [TrendData getTrendDataForTank];
[self initPlot];
}
- (void)viewWillAppear:(BOOL)animated
{
[self.view bringSubviewToFront:self.tankDetailView];
}
-(void) viewDidDisappear:(BOOL)animated
{
}
- (void) initPlot
{
[self configureHost];
[self configureGraph];
[self configurePlots];
[self configureAxes];
}
- (void) configureHost
{
self.hostView = [(CPTGraphHostingView*) [CPTGraphHostingView alloc] initWithFrame:self.tankTrendView.bounds];
self.hostView.allowPinchScaling = NO;
[self.tankTrendView addSubview:self.hostView];
}
- (void) configureGraph
{
self.graph = [[CPTXYGraph alloc] initWithFrame:self.hostView.bounds];
[self.graph applyTheme:[CPTTheme themeNamed:kCPTPlainWhiteTheme]];
self.hostView.hostedGraph = self.graph;
self.graph.title = [#"Trend Graph for " stringByAppendingString:self.tankNumberLabel.text];
CPTMutableTextStyle* titleStyle = [CPTMutableTextStyle textStyle];
titleStyle.color = [CPTColor blackColor];
titleStyle.fontName = #"Helvetica-Neue Light";
titleStyle.fontSize = 10.0f;
self.graph.titleTextStyle = titleStyle;
self.graph.titlePlotAreaFrameAnchor = CPTRectAnchorTop;
self.graph.titleDisplacement = CGPointMake(0.0f, 20.0f);
[self.graph.plotAreaFrame setPaddingLeft:50.0f];
[self.graph.plotAreaFrame setPaddingBottom:90.0f];
CPTXYPlotSpace* plotSpace = (CPTXYPlotSpace*) self.graph.defaultPlotSpace;
plotSpace.allowsUserInteraction = YES;
self.graph.defaultPlotSpace.delegate = self;
self.graph.delegate = self;
}
- (void) configurePlots
{
CPTGraph* graph = self.hostView.hostedGraph;
CPTXYPlotSpace* plotSpace = (CPTXYPlotSpace*) graph.defaultPlotSpace;
CPTScatterPlot* aaplPlot = [[CPTScatterPlot alloc] init];
aaplPlot.dataSource = self;
CPTColor *aaplColor = [CPTColor redColor];
aaplPlot.delegate = self;
aaplPlot.plotLineMarginForHitDetection = 10;
aaplPlot.plotSymbolMarginForHitDetection = 10;
[graph addPlot:aaplPlot toPlotSpace:plotSpace];
[plotSpace scaleToFitPlots: [NSArray arrayWithObjects:aaplPlot, nil]];
CPTMutablePlotRange* xRange = [plotSpace.xRange mutableCopy];
[xRange expandRangeByFactor:CPTDecimalFromCGFloat(1.2f)];
plotSpace.xRange = xRange;
CPTMutablePlotRange* yRange = [plotSpace.yRange mutableCopy];
[xRange expandRangeByFactor:CPTDecimalFromCGFloat(1.2f)];
plotSpace.yRange = yRange;
CPTMutableLineStyle* aapleLineStyle = [aaplPlot.dataLineStyle mutableCopy];
aapleLineStyle.lineWidth = 2.5;
aapleLineStyle.lineColor = aaplColor;
aaplPlot.dataLineStyle = aapleLineStyle;
}
- (void) configureAxes
{
NSDate* refDate = [NSDate dateWithTimeIntervalSince1970:0];
CPTGraph* graph = self.hostView.hostedGraph;
CPTXYAxisSet* axes = (id)graph.axisSet;
CPTXYPlotSpace* plotSpace = (CPTXYPlotSpace*) self.graph.defaultPlotSpace;
axes.xAxis.minorTicksPerInterval = 0;
NSValue* firstValue = [self.graphData objectAtIndex:0];
NSValue* lastValue = [self.graphData objectAtIndex:self.graphData.count -1];
CGPoint firstPoint = [firstValue CGPointValue];
CGPoint lastPoint = [lastValue CGPointValue];
axes.yAxis.orthogonalCoordinateDecimal = CPTDecimalFromDouble(plotSpace.xRange.minLimitDouble);
axes.yAxis.majorIntervalLength = CPTDecimalFromDouble(plotSpace.yRange.lengthDouble/5);
axes.yAxis.minorTicksPerInterval = 0;
axes.xAxis.orthogonalCoordinateDecimal = CPTDecimalFromDouble(plotSpace.yRange.minLimitDouble);
axes.xAxis.majorIntervalLength = CPTDecimalFromDouble((lastPoint.x - firstPoint.x)/3);
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
dateFormatter.locale = [NSLocale currentLocale];
dateFormatter.dateFormat = #"dd/MM/yyyy HH:mm:ss";
CPTTimeFormatter *timeFormatter = [[CPTTimeFormatter alloc] initWithDateFormatter:dateFormatter];
timeFormatter.referenceDate = refDate;
axes.xAxis.labelFormatter = timeFormatter;
}
-(void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation
{
if (fromInterfaceOrientation==UIInterfaceOrientationPortrait || fromInterfaceOrientation==UIInterfaceOrientationPortraitUpsideDown)
{
self.hostView.frame = self.view.bounds;
[self.graph reloadData];
[self.view bringSubviewToFront:self.tankTrendView];
}
else
{
self.hostView.frame = self.view.bounds;
[self.graph reloadData];
[self.view bringSubviewToFront:self.tankDetailView];
}
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
- (IBAction)didPressTankStatusLED:(UIButton *)sender {
//if([self.tankToShow.tankStatus isEqualToString:#"Release"])
//{
/*self.releasedProductList = [[tankReleasedProductListTVCViewController alloc] initWithStyle:UITableViewStylePlain];
Product* releasedProduct = [[Product alloc] init];
releasedProduct.name = self.tankProductLabel.text;
releasedProduct.code = self.tankProductCode.text;
self.releasedProductList.productList = [NSArray arrayWithObjects:releasedProduct, nil];
FPPopoverController* popoverController = [[FPPopoverController alloc]initWithViewController:self.releasedProductList];
self.releasedProductList.delegate = self;
popoverController.contentSize = CGSizeMake(250, 85 * self.releasedProductList.productList.count);
[popoverController presentPopoverFromView:self.tankStatusLED];*/
//}
}
- (NSUInteger)numberOfRecordsForPlot:(CPTPlot *)plot
{
return self.graphData.count;
}
- (id)numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)idx
{
NSValue *value = [self.graphData objectAtIndex:idx];
CGPoint point = [value CGPointValue];
// FieldEnum determines if we return an X or Y value.
if ( fieldEnum == CPTScatterPlotFieldX )
{
return [NSNumber numberWithFloat:point.x];
}
else // Y-Axis
{
return [NSNumber numberWithFloat:point.y];
}
}
- (void)scatterPlot:(CPTScatterPlot *)plot plotSymbolWasSelectedAtRecordIndex:(NSUInteger)index
{
}
//This function is here to lock the graph and prevent it from being panned so I can use the the drag event for my own purposes
-(CGPoint)plotSpace:(CPTPlotSpace *)space willDisplaceBy:(CGPoint)displacement {
return CGPointMake(0, 0);
}
- (BOOL)plotSpace:(CPTPlotSpace *)space shouldHandlePointingDeviceDownEvent:(UIEvent *)event atPoint:(CGPoint)point
{
return NO;
}
- (BOOL)plotSpace:(CPTPlotSpace *)space shouldHandlePointingDeviceDraggedEvent:(UIEvent *)event atPoint:(CGPoint)point
{
CPTGraph* graph = self.hostView.hostedGraph;
CPTXYAxisSet* axes = (id)graph.axisSet;
double percentAcrossScreen = point.x/self.view.frame.size.width;
if (self.isFirstValue==YES)
{
self.startValue = percentAcrossScreen;
self.isFirstValue = NO;
}
else
{
self.lastValue = percentAcrossScreen;
}
NSValue *firstValue = [self.graphData objectAtIndex:[[NSNumber numberWithDouble:self.startValue * self.graphData.count] integerValue]];
CGPoint firstPoint = [firstValue CGPointValue];
NSValue *lastValue = [self.graphData objectAtIndex:[[NSNumber numberWithDouble:self.lastValue * self.graphData.count] integerValue]];
CGPoint lastPoint = [lastValue CGPointValue];
double difference = lastPoint.x - firstPoint.x;
CPTPlotRange *range = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromDouble(firstPoint.x)
length:CPTDecimalFromDouble(difference)];
CPTFill *bandFill = [CPTFill fillWithColor:[CPTColor blueColor]];
[axes.yAxis addBackgroundLimitBand:[CPTLimitBand limitBandWithRange:range
fill:bandFill]];
NSLog([[NSNumber numberWithDouble:firstPoint.x] stringValue]);
NSLog([[NSNumber numberWithDouble:lastPoint.x] stringValue]);
return YES;
}