基本上，我有这个类，用于在 CorePlot 条形图中显示数据：
#import "BarChartViewController.h"
#import "AppDelegate.h"
#import "Project.h"
#import "Currency.h"
#import "TotalValueCalculator.h"
#define BAR_POSITION @"POSITION"
#define BAR_HEIGHT @"HEIGHT"
#define COLOR @"COLOR"
#define CATEGORY @"CATEGORY"
#define AXIS_START 0
@interface BarChartViewController ()
@end
@implementation BarChartViewController
{
int count;
}
@synthesize data;
@synthesize graph;
@synthesize hostingView;
@synthesize graphType;
//Finds the maximum value from an array of ints
int findMax (int numbers[], int N){
int max = numbers[0];
for (int i = 0; i < N; i++)
if(max<numbers[i]) max = numbers[i];
return max;
}
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
}
return self;
}
- (void) generateBarPlot
{
//Create host view
self.hostingView = [[CPTGraphHostingView alloc]
initWithFrame:[[UIScreen mainScreen]bounds]];
[self.view addSubview:self.hostingView];
//Create graph and set it as host view's graph
self.graph = [[CPTXYGraph alloc] initWithFrame:self.hostingView.bounds];
[self.hostingView setHostedGraph:self.graph];
//set graph padding and theme
self.graph.plotAreaFrame.paddingTop = 20.0f;
self.graph.plotAreaFrame.paddingRight = 20.0f;
self.graph.plotAreaFrame.paddingBottom = 170.0f;
self.graph.plotAreaFrame.paddingLeft = 70.0f;
[self.graph applyTheme:[CPTTheme themeNamed:kCPTDarkGradientTheme]];
//set axes ranges
CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *)self.graph.defaultPlotSpace;
plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(AXIS_START) length:CPTDecimalFromFloat(50)];
plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:
CPTDecimalFromFloat(AXIS_START)
length:CPTDecimalFromFloat((axisEnd - AXIS_START)+5)];
CPTXYAxisSet *axisSet = (CPTXYAxisSet *)self.graph.axisSet;
//set axes' title, labels and their text styles
CPTMutableTextStyle *textStyle = [CPTMutableTextStyle textStyle];
textStyle.fontName = @"Helvetica";
textStyle.fontSize = 14;
textStyle.color = [CPTColor whiteColor];
if (graphType == @"TotalProject"){
axisSet.xAxis.title = @"Project Name";
}
else if (graphType == @"TotalCategory"){
axisSet.xAxis.title = @"Category Name";
}
else if (graphType == @"TotalCurrency"){
axisSet.xAxis.title = @"Currency Name";
}
else if (graphType == @"DistanceTravelled"){
axisSet.xAxis.title = @"Project";
}
else if (graphType == @"FuelCostProject"){
axisSet.xAxis.title = @"Project";
}
else if (graphType == @"FuelCostCurrency"){
axisSet.xAxis.title = @"Currency";
}
axisSet.yAxis.title = @"Total Value";
axisSet.xAxis.titleTextStyle = textStyle;
axisSet.yAxis.titleTextStyle = textStyle;
axisSet.xAxis.titleOffset = 50.0f;
axisSet.yAxis.titleOffset = 50.0f;
axisSet.xAxis.labelTextStyle = textStyle;
axisSet.xAxis.labelOffset = 3.0f;
axisSet.yAxis.labelTextStyle = textStyle;
axisSet.yAxis.labelOffset = 3.0f;
//set axes' line styles and interval ticks
CPTMutableLineStyle *lineStyle = [CPTMutableLineStyle lineStyle];
lineStyle.lineColor = [CPTColor whiteColor];
lineStyle.lineWidth = 3.0f;
axisSet.xAxis.axisLineStyle = lineStyle;
axisSet.yAxis.axisLineStyle = lineStyle;
axisSet.xAxis.majorTickLineStyle = lineStyle;
axisSet.yAxis.majorTickLineStyle = lineStyle;
//Set x axis tick length to 0 as there is no data on the x axis
axisSet.xAxis.majorIntervalLength = CPTDecimalFromFloat(0.0f);
if (axisEnd <= 400){
axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(25.0f);
}
else if (axisEnd <= 900){
axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(50.0f);
}
else if (axisEnd <= 1300){
axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(75.0f);
}
else if (axisEnd <= 1800){
axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(100.0f);
}
else if (axisEnd <= 2300){
axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(125.0f);
}
else if (axisEnd <= 2800){
axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(150.0f);
}
else if (axisEnd <= 3300){
axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(175.0f);
}
else if (axisEnd <= 3500){
axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(200.0f);
}
else {
axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(300.0f);
}
axisSet.xAxis.majorTickLength = 7.0f;
axisSet.yAxis.majorTickLength = 7.0f;
axisSet.xAxis.minorTickLineStyle = lineStyle;
axisSet.yAxis.minorTickLineStyle = lineStyle;
axisSet.xAxis.minorTicksPerInterval = 1;
axisSet.yAxis.minorTicksPerInterval = 1;
axisSet.xAxis.minorTickLength = 5.0f;
axisSet.yAxis.minorTickLength = 5.0f;
NSNumberFormatter *numberFormatter = [[NSNumberFormatter alloc] init];
[numberFormatter setNumberStyle:NSNumberFormatterDecimalStyle];
[numberFormatter setMaximumFractionDigits:2];
[numberFormatter setPositiveFormat:@"###0.00"];
axisSet.yAxis.labelFormatter = numberFormatter;
int initialTickLocation = 9;
AppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
NSMutableArray *customTickLocations = [[NSMutableArray alloc] init];
NSMutableArray *xAxisLabels = [[NSMutableArray alloc] init];
if (graphType == @"TotalProject"){
for (int i = 0; i < [appDelegate.projects count]; i++){
//CHANGE THESE NUMBERS TO CHANGE POSITIONS OF THE LABELS
[customTickLocations addObject:[NSNumber numberWithInt:initialTickLocation]];
initialTickLocation = initialTickLocation + 7;
[xAxisLabels addObject:[[appDelegate.projects objectAtIndex:i] name]];
}
}
else if (graphType == @"TotalCategory"){
for (int i = 0; i < [appDelegate.categories count]; i++){
//CHANGE THESE NUMBERS TO CHANGE POSITIONS OF THE LABELS
[customTickLocations addObject:[NSNumber numberWithInt:initialTickLocation]];
initialTickLocation = initialTickLocation + 7;
[xAxisLabels addObject:[[appDelegate.categories objectAtIndex:i] name]];
}
}
else if (graphType == @"TotalCurrency"){
for (int i = 0; i < [appDelegate.currencies count]; i++){
//CHANGE THESE NUMBERS TO CHANGE POSITIONS OF THE LABELS
[customTickLocations addObject:[NSNumber numberWithInt:initialTickLocation]];
initialTickLocation = initialTickLocation + 7;
[xAxisLabels addObject:[[appDelegate.currencies objectAtIndex:i] shortName]];
}
}
else if (graphType == @"DistanceTravelled"){
for (int i = 0; i < [appDelegate.projects count]; i++){
//CHANGE THESE NUMBERS TO CHANGE POSITIONS OF THE LABELS
[customTickLocations addObject:[NSNumber numberWithInt:initialTickLocation]];
initialTickLocation = initialTickLocation + 7;
[xAxisLabels addObject:[[appDelegate.projects objectAtIndex:i] name]];
}
}
else if (graphType == @"FuelCostProject"){
for (int i = 0; i < [appDelegate.projects count]; i++){
//CHANGE THESE NUMBERS TO CHANGE POSITIONS OF THE LABELS
[customTickLocations addObject:[NSNumber numberWithInt:initialTickLocation]];
initialTickLocation = initialTickLocation + 7;
[xAxisLabels addObject:[[appDelegate.projects objectAtIndex:i] name]];
}
}
else if (graphType == @"FuelCostCurrency"){
for (int i = 0; i < [appDelegate.currencies count]; i++){
//CHANGE THESE NUMBERS TO CHANGE POSITIONS OF THE LABELS
[customTickLocations addObject:[NSNumber numberWithInt:initialTickLocation]];
initialTickLocation = initialTickLocation + 7;
[xAxisLabels addObject:[[appDelegate.currencies objectAtIndex:i] shortName]];
}
}
axisSet.xAxis.labelRotation = M_PI/4;
axisSet.xAxis.labelingPolicy = CPTAxisLabelingPolicyNone;
NSUInteger labelLocation = 0;
NSMutableArray *customLabels = [NSMutableArray arrayWithCapacity:[xAxisLabels count]];
for (NSNumber *tickLocation in customTickLocations){
CPTAxisLabel *newLabel = [[CPTAxisLabel alloc] initWithText:[xAxisLabels objectAtIndex:labelLocation++] textStyle:axisSet.xAxis.labelTextStyle];
newLabel.tickLocation = [tickLocation decimalValue];
newLabel.offset = axisSet.xAxis.labelOffset + axisSet.xAxis.majorTickLength;
newLabel.rotation = M_PI / 4;
[customLabels addObject:newLabel];
}
axisSet.xAxis.axisLabels = [NSSet setWithArray:customLabels];
// Create bar plot and add it to the graph
CPTBarPlot *plot = [[CPTBarPlot alloc] init] ;
plot.dataSource = self;
plot.delegate = self;
plot.barWidth = [[NSDecimalNumber decimalNumberWithString:@"5.0"]
decimalValue];
plot.barOffset = [[NSDecimalNumber decimalNumberWithString:@"10.0"]
decimalValue];
plot.barCornerRadius = 5.0;
// Remove bar outlines
CPTMutableLineStyle *borderLineStyle = [CPTMutableLineStyle lineStyle];
borderLineStyle.lineColor = [CPTColor clearColor];
plot.lineStyle = borderLineStyle;
// Identifiers are handy if you want multiple plots in one graph
plot.identifier = @"projectTotals";
[self.graph addPlot:plot];
}
-(NSUInteger)numberOfRecordsForPlot:(CPTPlot *)plot
{
return [self.data count];
}
-(NSNumber *)numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index
{
NSDictionary *bar = [self.data objectAtIndex:index];
if(fieldEnum == CPTBarPlotFieldBarLocation){
NSLog(@"Position: %@", [bar valueForKey:BAR_POSITION]);
return [bar valueForKey:BAR_POSITION];
}
else{
NSLog(@"Height: %@", [bar valueForKey:BAR_HEIGHT]);
return [bar valueForKey:BAR_HEIGHT];
}
}
-(CPTLayer *)dataLabelForPlot:(CPTPlot *)plot recordIndex:(NSUInteger)index
{
CPTMutableTextStyle *textStyle = [CPTMutableTextStyle textStyle];
textStyle.fontName = @"Helvetica";
textStyle.fontSize = 12;
textStyle.color = [CPTColor whiteColor];
NSDictionary *bar = [self.data objectAtIndex:index];
//Here we want to display the value for that day, not the name of the day
CPTTextLayer *label = [[CPTTextLayer alloc] initWithText:[NSString stringWithFormat:@"%0.2f", [[bar valueForKey:BAR_HEIGHT] floatValue]]];
label.textStyle =textStyle;
return label;
}
-(CPTFill *)barFillForBarPlot:(CPTBarPlot *)barPlot
recordIndex:(NSUInteger)index
{
NSDictionary *bar = [self.data objectAtIndex:index];
CPTGradient *gradient = [CPTGradient gradientWithBeginningColor:[CPTColor whiteColor]
endingColor:[bar valueForKey:@"COLOR"]
beginningPosition:0.0 endingPosition:0.3 ];
[gradient setGradientType:CPTGradientTypeAxial];
[gradient setAngle:320.0];
CPTFill *fill = [CPTFill fillWithGradient:gradient];
return fill;
}
- (void)dealloc
{
}
- (void)didReceiveMemoryWarning
{
// Releases the view if it doesn't have a superview.
[super didReceiveMemoryWarning];
// Release any cached data, images, etc that aren't in use.
}
#pragma mark - View lifecycle
- (void)viewDidLoad
{
[super viewDidLoad];
self.data = [NSMutableArray array];
AppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
count = [appDelegate.projects count];
int catCount = [appDelegate.categories count];
int currencyCount = [appDelegate.currencies count];
int bar_heights[count];
NSString *categories[count];
int catBar_heights[catCount];
NSString *catCategories[catCount];
int currencyBar_heights[currencyCount];
NSString *currencyCategories[currencyCount];
if ([graphType isEqualToString:@"TotalProject"])
{
for (int i = 0; i < count; i++)
{
TotalValueCalculator *calc = [[TotalValueCalculator alloc] initWithString:[[appDelegate.projects objectAtIndex:i] name]];
NSString *totalValueString = [calc compareProject];
float totalValue = [totalValueString floatValue];
bar_heights[i] = totalValue;
NSLog(@"---%0.2f", totalValue);
categories[i] = [[appDelegate.projects objectAtIndex:i] name];
}
axisEnd = findMax(bar_heights, count) + ((findMax(bar_heights, count)) / 10);
UIColor *colors[] = {
[UIColor colorWithRed:139/255.0 green:198/255.0 blue:63/255.0 alpha:1],
nil};
for (int i = 0; i < [appDelegate.projects count] ; i++){
int position = i*7; //Bars will be 7 pts away from each other
float height = bar_heights[i];
NSDictionary *bar = [NSDictionary dictionaryWithObjectsAndKeys:
[NSDecimalNumber numberWithFloat:position],BAR_POSITION,
[NSDecimalNumber numberWithFloat:height],BAR_HEIGHT,
colors[0],COLOR,
categories[i],CATEGORY,
nil];
NSLog(@"^^^^^^^^^^^^^%@", [NSDecimalNumber numberWithFloat:height]);
[self.data addObject:bar];
}
}
else if ([graphType isEqualToString:@"TotalCategory"])
{
for (int i = 0; i < catCount; i++)
{
TotalValueCalculator *calc = [[TotalValueCalculator alloc] initWithString:[[appDelegate.categories objectAtIndex:i] name]];
NSString *totalValueString = [calc compareCategory];
double totalValue = [totalValueString doubleValue];
catBar_heights[i] = totalValue;
catCategories[i] = [[appDelegate.categories objectAtIndex:i] name];
}
axisEnd = findMax(catBar_heights, catCount) + ((findMax(catBar_heights, catCount)) / 10);
UIColor *colors[] = {
[UIColor colorWithRed:236/255.0 green:139/255.0 blue:34/255.0 alpha:1],
nil};
for (int i = 0; i < [appDelegate.categories count] ; i++){
double position = i*7; //Bars will be 7 pts away from each other
double height = catBar_heights[i];
NSDictionary *bar = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithDouble:position],BAR_POSITION,
[NSNumber numberWithDouble:height],BAR_HEIGHT,
colors[0],COLOR,
catCategories[i],CATEGORY,
nil];
[self.data addObject:bar];
}
}
else if ([graphType isEqualToString:@"TotalCurrency"])
{
for (int i = 0; i < currencyCount; i++)
{
TotalValueCalculator *calc = [[TotalValueCalculator alloc] initWithString:[[appDelegate.currencies objectAtIndex:i] shortName]];
NSString *totalValueString = [calc compareCurrency];
double totalValue = [totalValueString doubleValue];
currencyBar_heights[i] = totalValue;
currencyCategories[i] = [[appDelegate.currencies objectAtIndex:i] shortName];
}
axisEnd = findMax(currencyBar_heights, currencyCount) + ((findMax(currencyBar_heights, currencyCount)) / 10);
UIColor *colors[] = {
[UIColor colorWithRed:236/255.0 green:139/255.0 blue:34/255.0 alpha:1],
nil};
for (int i = 0; i < [appDelegate.currencies count] ; i++){
double position = i*7; //Bars will be 7 pts away from each other
double height = currencyBar_heights[i];
NSDictionary *bar = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithDouble:position],BAR_POSITION,
[NSNumber numberWithDouble:height],BAR_HEIGHT,
colors[0],COLOR,
currencyCategories[i],CATEGORY,
nil];
[self.data addObject:bar];
}
}
else if ([graphType isEqualToString:@"DistanceTravelled"])
{
for (int i = 0; i < count; i++)
{
TotalValueCalculator *calc = [[TotalValueCalculator alloc] initWithString:[[appDelegate.projects objectAtIndex:i] name]];
NSString *totalValueString = [calc compareProjectDistance];
double totalValue = [totalValueString doubleValue];
bar_heights[i] = totalValue;
categories[i] = [[appDelegate.projects objectAtIndex:i] name];
}
axisEnd = findMax(bar_heights, count) + ((findMax(bar_heights, count)) / 10);
UIColor *colors[] = {
[UIColor colorWithRed:236/255.0 green:139/255.0 blue:34/255.0 alpha:1],
nil};
for (int i = 0; i < [appDelegate.projects count] ; i++){
double position = i*7; //Bars will be 7 pts away from each other
double height = bar_heights[i];
NSDictionary *bar = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithDouble:position],BAR_POSITION,
[NSNumber numberWithDouble:height],BAR_HEIGHT,
colors[0],COLOR,
categories[i],CATEGORY,
nil];
[self.data addObject:bar];
}
}
else if ([graphType isEqualToString:@"FuelCostProject"])
{
for (int i = 0; i < count; i++)
{
TotalValueCalculator *calc = [[TotalValueCalculator alloc] initWithString:[[appDelegate.projects objectAtIndex:i] name]];
NSString *totalValueString = [calc compareProjectFuel];
double totalValue = [totalValueString doubleValue];
bar_heights[i] = totalValue;
categories[i] = [[appDelegate.projects objectAtIndex:i] name];
}
axisEnd = findMax(bar_heights, count) + ((findMax(bar_heights, count)) / 10);
UIColor *colors[] = {
[UIColor colorWithRed:236/255.0 green:139/255.0 blue:34/255.0 alpha:1],
nil};
for (int i = 0; i < [appDelegate.projects count] ; i++){
double position = i*7; //Bars will be 7 pts away from each other
double height = bar_heights[i];
NSDictionary *bar = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithDouble:position],BAR_POSITION,
[NSNumber numberWithDouble:height],BAR_HEIGHT,
colors[0],COLOR,
categories[i],CATEGORY,
nil];
[self.data addObject:bar];
}
}
else if ([graphType isEqualToString:@"FuelCostCurrency"])
{
for (int i = 0; i < currencyCount; i++)
{
TotalValueCalculator *calc = [[TotalValueCalculator alloc] initWithString:[[appDelegate.currencies objectAtIndex:i] shortName]];
NSString *totalValueString = [calc compareCurrencyFuel];
double totalValue = [totalValueString doubleValue];
currencyBar_heights[i] = totalValue;
currencyCategories[i] = [[appDelegate.currencies objectAtIndex:i] shortName];
}
axisEnd = findMax(currencyBar_heights, currencyCount) + ((findMax(currencyBar_heights, currencyCount)) / 10);
UIColor *colors[] = {
[UIColor colorWithRed:236/255.0 green:139/255.0 blue:34/255.0 alpha:1],
nil};
for (int i = 0; i < [appDelegate.currencies count] ; i++){
double position = i*7; //Bars will be 7 pts away from each other
double height = currencyBar_heights[i];
NSDictionary *bar = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithDouble:position],BAR_POSITION,
[NSNumber numberWithDouble:height],BAR_HEIGHT,
colors[0],COLOR,
currencyCategories[i],CATEGORY,
nil];
[self.data addObject:bar];
}
}
[self generateBarPlot];
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
// Return YES for supported orientations
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
@end
我知道那里有很多，但我一生都无法弄清楚如何让这个条形图显示浮点值（对于条形高度）？我在这上面花了很多时间，现在我开始绝望了。
有谁知道如何做到这一点？图表接收的值肯定是浮点值。
任何帮助都将不胜感激..
非常感谢，
杰克