iOS Core Plot Get visible labels X axis - ios

I am using Core Plot and I am really still new to it. I have searched but could not find the answer. I have allowsUserInteraction enabled. I have implemented zoom in/out with that. I want to be able to get first and last visible label on X axis every time when user has zoomed in/out. I know that there is willChangePlotRangeTo I have called there expandRangeByFactor method on my CPTMutablePlotRange. I want to be able to get every time text from first and last visible label on X axis. Is there any delegate method that I have missed?

Whenever you need to find out what the current axis labels are, call -layoutIfNeeded on the axis to make sure the labels are up-to-date and get the set of labels from the axisLabels property. Since it's a set, the collection is unordered. You'll have to search the whole set to find the first and last ones. Each label has a tickLocation that is the location along the axis and a contentLayer that is the label displayed at the location. The automatic axis labels are always CPTTextLayer objects, so you can extract the text property from there.

Related

ios-charts - Changing Y axis value by a drag and drop

I am using ios-charts library to draw charts on a swift2 app. I am wondering if, for a given X value, I can change its Y associated value by a drag and drop gesture on the chart.
If this is not possible on this library, is it possible to do such a thing using another library?
technically you can. Every time you scroll/zoom the chart, it will trigger a redraw, so everything is redrawing, you can decide your own logic how you want the y axis value changed.
It has two parts:
In computeAxisValues in y axis renderer, the y axis labels(values) are determined. Then in renderAxisLabels, it is drawn using the calculated values.
So you can take a look at these functions and implement your logic. Note, it's your responsibility to make sure what you are doing is valid in your scenario, because if something weird happens, you may not get support on github, because it's not a bug, and sometimes not easy to answer.

Core Plot: Pinch to change x axis range

So I have a simple line XY Graph with integer values on the Y axis and dates on the X axis. What I would be like to be able to do is do a horizontal two-finger pinch and adjust the range dynamically. Eg, pinching in would give you a bigger range (mental model being that you're setting the start and end date shown to be further apart) and then pinching out would give you smaller time window.
Is there some stuff built in for this already? Reasonably new to CorePlot and the default finger stuff just zooms the graph itself, none of the values.
Would I need to put a gesture recgoniser on it? or does coreplot have stuff build into it for this?
Cheers
This is how the built-in zoom features work. Use a plot space delegate to monitor changes to the plot space while zooming and make changes to the axis appearance as needed based on the changes. See my answer to your other question for more info.

Highcharts :: Need to split y-axis from primary body of chart. Can I display this axis separately from the Highchart?

I have a situation where I need to remove all margins from a highchart and remove the x/y axis so it fills a series of columns in a table completely.
I did that, no problem. Chart goes to the extremes as needed.
What I need now is that pesky yaxis I already removed...but displayed in a table cell outside of the existing highcharts object.
It would seem easy, as though I could just set the overflow property of yaxis to 'visible' and play with the offset...which would work however this would only work if I wanted to re-position the axis within the boundaries of the highchart object. I want him in a different cell entirely.
Is there anyone who has had experience in this situation? Is it going to require me to have a secondary highchart with only a y-axis?
Best answer gets a green check.
EDIT :: I now have dispersed each 'day' into their own column (more bars coming per day [scheduled,actual,etc...]). In order to keep the scales lined up, I manipulate the yAxis:max property and set them all to a derived value.
In the open column (currently w/ text Hourly Trends) is where I would put an additional highchart module with no series data but with the same min/max/tickInterval.
The next big leap will be to see the data is alive and changes w/ schedule. May have to start another thread for that one, no?
Create a new HC object with no data but only the yAxis (making sure it is the right scale, etc). Perhaps add the same series of data to it but hide the series? Add it to the location you want. This seems kludge and not very good practice. Each business use is different but why would you want this?
EDIT based on comment of business rules:
Why not come at this from a different direction and have the individual chart elements (the bars/points/etc) be a single point chart. This way you have one chart per column. You can then set up the yAxis to be text and not worry about the position. If we could see an example of the page layout and the desired result that would help.

Coreplot: Axis Labels Fixed Location

I'm trying to customize a Coreplot graph in many ways I can and the next thing I would like to do is place the X Axis Labels (one that is custom as well) at the bottom of the graph, independent of the X axis' position (whether it's scrolled up or down).
To make it clear, it is similar to giving the labels an offset value of something like 50.0. But offset is not the property I'm looking for since it fixes the labels location relative to the X axis.
Any way this can be done? Or do I have to skip the axisLabels property and place and layer or something manually at the bottom of the graph?
EDIT: Alright, I managed to place an axis on the bottom with CPTConstraints. But it's not on the bottommost. If a plot point is on those levels, the plot line overlaps the labels. I tired padding of the graph but of course, it moves the whole graph, hence the issue persists.
Thanks in advance
Make a second x-axis. Have the first one draw the axis line, tick marks, etc., as normal but no labels. Label the second one and set all of the line style properties to nil so it doesn't draw any of the lines.
Turns out that aside from the graph, the plotAreaFrame property of the CPTGrpah also has paddings. If you give more paddings to plotAreaFrame than that of the graph, the plot will be drawn in a smaller frame and the rest of the graph area will be for you to add what you want (i.e., a second Axis).
Big thanks to #Eric, for trying to answer Every single CorePlot question as soon as possible.
CorePlot does have a lot of customisation than I thought.

How can I make Core Plot to show an x-axis label for each point in time?

Apart from the issue I am trying to fix atm, I would like to know how I can make the x-axis labels to draw wherever there is a point drawn. As you can see on the screenshot there are three points in time. So instead of the label "1/10/54' (yes that is year 54) floating nowhere, I want three labels, one below each point.
(Note the 3 points are only for illustration, needs to be expandable.)
If the spacing between the labels will be irregular like your sample screenshot, you'll want to change the axis labeling policy to CPTAxisLabelingPolicyNone or CPTAxisLabelingPolicyLocationsProvided. Both policies require you to provide the tick locations. The first policy also requires you to make custom labels that don't have to be at the same locations as the tick marks while the second will automatically make labels at each tick location using the standard label formatter.

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