Using MPAndroidChart, I'm struggling to figure out how to set the current visible x axis values. The use case is simple and I would have thought very common, so I'm sure I must be missing some function which can do this:
Say you have a chart with x axis values 1-100
A user zooms and pans a chart so that the range 60-80 is visible. I want to store these values, so that tomorrow when the user re-launches the app, I can restore the exact viewing state (60-80)
Storing the values is really easy - you can simply call chart.lowestVisibleX and chart.highestVisibleX to get the x axis values. But how do I set them on a new instance of the chart? Unfortunately there doesn't seem to be a chart.setHighestVisibleX or chart.setLowestVisibleX.
This previous question / answer is nearly, but not quite, what I need. The suggestion is to use a combination of chart.moveViewToX(60) and chart.setVisibleXRangeMaximum(20). However as the docs for setVisibleXRangeMaximum state:
Sets the size of the area (range on the x-axis) that should be maximum
visible at once (no further zooming out allowed)
I don't want to prevent further zooming, which is what this does. There must be a way to set the zoom level without actually restricting further zooming - but I can't figure it out. Any suggestions?
Thanks
Just to answer my own question, I decided to workaround this issue by resetting the X range maximum after calling moveViewToX. This appears to work. So the solution would be:
chart.setVisibleXRangeMaximum(20)
chart.moveViewToX(60)
chart.setVisibleXRangeMaximum(100)
Related
Is it possible to do something like this:
? I have in the app LineChart with the time values (seconds) on X axis and temperature on Y axis.
And it's possible that I don't have a data for some bigger time interval (day and more for example) and it will not be very user frinedly if user has to swipe so much back. So I want to create this "shortcut" or somehow "delete" empty part of the graph (with no X values). Is is possible? Maybe there don't have to be this gap but I need to contine from time "10:30" to time "14:20" in one graph without big scrolling.
Do you have some suggestions?
Have a look at this and
this
There is a way to get a continued graph and don't have an empty gap in between however the way you are looking for kind of seems like a drag because even though you explicitly dont add the empty data to dataset, it is meant to work like a continued thing.
Hope this helps, cheers
I am creating a line chart using MPAndroidChart, all is working great, but I've noticed that at the labels often become bunched up. I know there is a way to prevent this (I've seen other apps that don't have this issue,) but I don't know what setting to enable.
There are a couple of ways you could make the labels fit better.
Decrease the text size of the X axis labels with mChart.getXAxis().setTextSize(float)
Set a label count limit for the X axis using mChart.getXAxis().setLabelCount(int). This should work fine, as you are already not showing one label per data point.
Change the date format of your label.
Some, all or none of these might help you, depending on your requirements. Good luck!
I am making an app which retrieves data from a database and shows it on a barchart. I have defined a limit line using the provided methods at 30f (on the Y axis).
The problem is, that I want that limit line to be always shown and it only becomes visible when one of the Graph's Bars raises above that value (30f).
Is there a way to always show it?
I have tried with the zoom functions with no luck.
Modify the YAxis display range to your needs: https://github.com/PhilJay/MPAndroidChart/wiki/YAxis-(YLabels)
Especially those methods should help:
setAxisMaxValue(float max): Set a custom maximum value for this axis. If set, this value will not be calculated automatically depending on the provided data.
setAxisMinValue(float min): Set a custom minimum value for this axis. If set, this value will not be calculated automatically depending on the provided data.
SOLUTION
Instead of using setInitialRange() I had to set the initial x-values using setXAxisMin() as well as setXAxisMax(). A little bit confusing, I think.
ORIGINAL QUESTION
I'm currently working on a project involving the acharteninge library for drawing time diagrams which works excellent so far. The user is capable of switching between various graphs (one XYMultipleSeriesDataset plus one TimeSeries per graph) via separate buttons. So far, achartengine displays all x values when the graph is shown.
However, I was asked to display only the data captured in the first three hours when the graph is shown, as this information is most relevant. Nevertheless, the user should still be able to scroll to data captured after the first three hours meaning that limiting the x-axis maximum value is not an option.
For example: There are two curves. The first curve is drawn using data captured over a period of 4 hours, while the second curve is created out of data captured over 18 hours.
In the current version my programme initially displays all data of the graph which gets displayed meaning the first curve shows three hours of very relevant data while 1 hour of not so important information is shown too. The "ratio" of the second curve is 3 to 15 (highly significant data vs regular data). As a result, a different amount of high important information is shown when the user compares the two curves making it harder for the user to compare this data, as he has to adjust the zoom manually.
EDIT 01.04.2015 15:46
For setting the initial range I use the XYMultipleSeriesRenderer instance's method setInitialRange(double[] initialRange); which does not affect the graph at all. Below you can see my statement (currentlyProcessedCurve.getRecordStart() is an instance of Joda's DateTime and furhtermore it's the x value of the first displayed point):
public static final int CHART_X_AXIS_INITIAL_MAX = 3;
public static final int CHART_MARGIN_PAN = 45;
...
double[] initialRange = { currentlyProcessedCurve.getRecordStart().minusMinutes(ApplicationSettings.CHART_MARGIN_PAN).toDate().getTime(), currentlyProcessedCurve.getRecordStart().plusHours(ApplicationSettings.CHART_X_AXIS_INITIAL_MAX).toDate().getTime(), 0, 600 };
currentDatasetRenderer.setInitialRange(initialRange);
TIDE (Edit end)
The screenshot below approximately shows how the curve should look initially (Just for making it clear: Please only consider the graphs' shapes, as they should look equal --> What I'm trying to say: I know that the x-axis and the y-axis label of the two screenshots different, but I don't have better pictures yet):
desired initial range
Finally, the following screenshot shows how the curve looks when displayed:
For enabling the user to compare the curves I have locked the y-axis zoom.
Any help is highly appreciated. Thanks in advance!
Have you consider pan option?
With this option you can limit axis maximum, and your chart will show the important data on start, while user can scroll left or right (wherever you have less important data points).
All you need to do is:
set pan enabled for axis you need
set pan limits (so user can't scroll past the last data point)
Hope this helps,
Cheers.
Instead of using XYMultipleSeriesRendererInstance.setInitialRange() I had to set the initial x-values using XYMultipleSeriesRendererInstance.setXAxisMin() as well as XYMultipleSeriesRendererInstance.setXAxisMax().
double xMinValue = ...;
double xMaxValue = ...;
currentDatasetRenderer.setXAxisMin(xMinValue);
currentDatasetRenderer.setXAxisMax(xMaxValue);
I have an Android application that is using Achart to create a 2 graphs. Both a line graph and a bar graph.
These graph will be populated with an extra data point each time the application is run. So after 10 runs there will be enough data to cover the visible x-axis.
What I want is for after the 11th+ use, to be able to pan the graph, so that the user can see historical data (back to the first data point).
I have set
renderer.setPanEnabled(true, false);
renderer.setZoomEnabled(false, false);
renderer.setYAxisMin(0);
renderer.setXAxisMin(0.5);
renderer.setXAxisMax(10.5);
renderer.setYAxisMax(100);
Which is all good, but when I pan the data I am able to pan to -ve values on the x axis, and also able to pan way beyond the maximum data point that I already have.
I have tried setting a PanListener, which I think is the way to go, but I am just not sure what I should be setting in this Listener to clamp the panning to valid data points only.
Any ideas?
The user pan will just modify the X axis min and max. In order to avoid this, you will have to indeed add a PanListener and reset these values.
You can also set pan limits.
renderer.setPanLimits(limits);