Core Plot: Increase space between ticks on the x-axis?

问题

I have this code for making ticks and labels on the x-axis:

    CPTAxis *x = axisSet.xAxis;
    x.title = @"Hour of Day";
    x.titleTextStyle = axisTitleStyle;
    x.titleOffset = 15.0f;
    x.axisLineStyle = axisLineStyle;
    x.labelingPolicy = CPTAxisLabelingPolicyNone;
    x.labelTextStyle = axisTextStyle;
    x.majorTickLineStyle = axisLineStyle;
    x.majorTickLength = 4.0f;
    x.tickDirection = CPTSignNegative;
    CGFloat dateCount = [timestamps count];
    NSMutableSet *xLabels = [NSMutableSet setWithCapacity:dateCount];
    NSMutableSet *xLocations = [NSMutableSet setWithCapacity:dateCount];
    NSInteger i = 0;
    for (NSString *date in timestampStrings) {
        CPTAxisLabel *label = [[CPTAxisLabel alloc] initWithText:date textStyle:x.labelTextStyle];
        CGFloat location = i++;
        label.tickLocation = CPTDecimalFromCGFloat(location);
        label.offset = x.majorTickLength;
        if (label) {
            [xLabels addObject:label];
            [xLocations addObject:[NSNumber numberWithFloat:location]];
        }
    }
    x.axisLabels = xLabels;
    x.majorTickLocations = xLocations;

I was wondering if I could expand the distance between each tick, because right now it just looks like a squished together mess that does not align with the points. Is there any way to make more space in between each tick, say 10 pixels? Thanks!

回答1:

I checked into it, and it all lied in the CGFloat location = i++;. I changed that to what I wanted (5, as in pixels) like this:

CGFloat location = i+=5;

and that worked.

回答2:

Assuming you use CPTXYGraph and its CPTXYPlotSpace. Using the plotSpace.globalXRange and plotSpace.xRange properties you can adjust proper scale for the X-axis.
The globalXRange defines the whole plot area, while the xRange defines its visible space. If you do not use scrolling, then xRange must be equal to globalXRange.

来源：https://stackoverflow.com/questions/21653573/core-plot-increase-space-between-ticks-on-the-x-axis