如何在带有自定义标签的核心绘图中设置刻度线?

如果要使用不同于默认格式的数字标签,请创建 NSNumberFormatter 对象,将其设置为所需的格式,并将其分配给 labelFormatter 轴上的属性。

退房 CPTimeFormatter 如果需要将标签格式设置为日期和/或时间,则初始化。

从派生类 NSNumberFormatter (例如) MyFormatter )和重写 stringForObjectValue:

- (NSString *)stringForObjectValue:(NSDecimalNumber *)coordinateValue {
    return @"MyLabel";
}

然后将轴的LabelFormatter属性设置为 格式化程序 ,例如:

MyFormatter *formatter = [[MyFormatter alloc] init];
x.labelFormatter = formatter;
[formatter release];

这对我有用!

NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init]; 
[formatter setMaximumFractionDigits:0];  
y.labelFormatter = formatter; 

您还可以像这样在类别中旋转方法:

#import "NSNumberFormatter+BigNumber.h"
#import <objc/runtime.h>

static Method origStringFromNumberMethod = nil;

@implementation NSNumberFormatter (BigNumber)

-(NSString *)stringFromBigNumber:(NSNumber*)number{
    int result = 0;
    int level = 1;
    NSString *format = @"";
    if([number integerValue] >= 1000000000) {
        level = 1000000000;
        format = @"b";
    }
    if([number integerValue] >= 1000000) {
        level = 1000000;
        format = @"m";
    }
    if([number integerValue] >= 1000){
        level = 1000;
        format = @"k";
    }
    result = [number integerValue]/level;

    NSString *kValue = [NSString stringWithFormat:@"%d%@",result,format];

    return kValue;
}

+ (void)initialize {
    origStringFromNumberMethod = class_getClassMethod(self, @selector(stringFromNumber:));
    method_exchangeImplementations(origStringFromNumberMethod,
                                   class_getClassMethod(self, @selector(stringFromBigNumber:)));
}

@end