I am using MPAndroidChart to display my charts, in the barchart it displays some values perfectly but for some other values, the bar is visible and can be highlighted but its value is not visible.
Any clue please on how to fix this ?
This is a picture to clarify what I am saying. The red areas is where the bar is visible but not its value.
Before setting the data (sorry I couldn't find the data in your question):
graph.setVisibleYRangeMaximum(barDataSet.getYMax() + 20, YAxis.AxisDependency.LEFT);
replacing 20 with the height of your custom layout.
I've had the same problem and this is how I've solved it.
float maxValue = barSet.getYMax();
int extraSpace = (int) (maxValue / (yVals.size() + 3));
chart.getAxisLeft().mAxisMaximum = (int) maxValue + (extraSpace < 1 ? 1 : extraSpace);
yVals is the list of Y axis values, while you can play with +3 so the whole chart view seems OK according to your layout.
Related
I am using the MPAndroidChart library to graph live sensor data in a line graph. I'm hoping to give the data a sort of 'buffer' on the right-hand end so that new data is in the centre of the screen. I've tried to illustrate what I mean below:
Basically, I have got it so the ViewPort scrolls and shows the most recent item in the right-most end of the screen, but I would like it in the centre. Thanks!
you need to set Xaxis maximum, set visibleXrange and last move the viewport
double range = 5; // how many data you want to show in view port
double maxX = 100; // your highest X value
chartView.getXAxis().setAxisMaximum(maxX + range/2);
chartView.setVisibleXRange(range, range);
chartView.moveViewToX(maxX);
chartView.notifyDataSetChanged();
I've been struggling with this for a while now, but I can't find a way to have an x axis, with its labels, lie at the position y = 0. This is important when I have both positive and negative values- I don't want to put the axis at the defaults given by AndroidMPChart (TOP, BOTTOM, BOTH_SIDED, TOP_INSIDE, BOTTOM_INSIDE), as none of these apply.
I have managed to edit the xAxisRenderer, and have been able to pass the ratio of my maxY value to my minY value, hoping to manually find the position to set the axis. The issue with this, however, is that I need the position of the highest Y bar and lowest Y bar. I can find the position of the lowest Y bar no problem, using mViewPortHandler.contentBottom(), but using
mViewPortHandler.contentTop() does not give me the top of the Y bar for some reason.
List<Float> floatList = new ArrayList<>();
floatList.add(0f);
floatList.add(mViewPortHandler.contentTop());
floatList.add(mViewPortHandler.offsetTop()+mViewPortHandler.getScaleY());
floatList.add(mViewPortHandler.getContentCenter().y);
floatList.add(mViewPortHandler.contentBottom());
floatList.add(mViewPortHandler.getChartHeight());
if (mDebug) {
for (int i=0; i<floatList.size(); i++) {
Paint paint = new Paint();
paint.setColor(getRandomColorInColorFormPrintString("i = " + i));
paint.setStrokeWidth(3);
c.drawLine(mViewPortHandler.contentLeft()+15*i,
floatList.get(i), mViewPortHandler.contentRight()+15*i,
floatList.get(i), paint);
}
}
Notice how contentBottom (yellow) nails the bottom of the bar, but content top and offset top (pink/red) are not accurate in finding the top of the content. I've tried this with many different values, contentBottom is consistently accurate, whereas contentTop/offsetTop are not, and are not offset by the height of the value label (I already tried this as well).
All I really need is a dynamic way to set the position of the x axis right between positive and negative values. I am so surprised that this option doesn't come with Android MP Charts. If it does, please let me know if I am overcomplicating things.
If there is no way to set this through Android MP Charts, please let me know if you know what I'm doing wrong in trying to get the top of the Y bar.
This is how I solved the problem--
in the renderAxisLine function =>
MPPointD pos = mTrans.getPixelForValues(0f, 0f);
c.drawLine(mViewPortHandler.contentLeft(),
(float)pos.y, mViewPortHandler.contentRight(),
(float)pos.y, mAxisLinePaint);
I have a chart with two datasets displayed on both yAxes. However these datasets overlap each other. Is there a way to display them like a grouped chart side by side over one label
If i use chart.groupBars(0f, 0.8f, 0.1f) the chart gets cut off because the bar width does not scale correctly.
OK After a bit more digging around and reading the docs more carefully i found the answer.
The sum of your barWidth, barSpace and groupSpace have to be zero, eg in my case with two bars per group:
val barWidth = 0.3
val groupSpace = 0.3
val barSpace = 0.05
val offsetForFirstX = -0.5 // for three bars 0.33 etc
chartView.groupBars(-0.5, groupSpace, barSpace)
For any problem on this charts lib
Download & run
https://github.com/PhilJay/MPAndroidChart/tree/master/MPChartExample
Make changes to the sample chart you wish to implement with view as required.
Sounds long cut, but we get to understand the working of library with help of documentation and don't get stuck in issues
I using the 2.0.8 release of MPAndroidChart
I have a problem when the y-values are all zero, and the bars are not shown in the BarChart.
I checked the sample project:
Unchanged code:
Just changing for all values of y are zero in the line 260, with
yVals1.add(new BarEntry(0, i));
but this happens:
And the same happens in my project, when some bars have nonzero values, all bars are displayed, like this:
but when all the bars are zero, no bars are shown and only one label is shown on the x-axis
How to fix this?
I need the chart display all values even the values of 'y' are all zero.
i was getting the same kind of problem as you.
i have a bar chart, when all the y values are 0, the bar won't show at all.
but if there is at least one y value that isn't 0, the bar will showed up even the rest of the y values is 0.
so i think this is a bug from MPAndroidChart.
but i found a way to tweak it a little bit.
you need to set the fixed max axis value, when all the y values are 0.
here is the code to set the fixed max axis value :
leftAxis.setAxisMaxValue(100f);
by doing that, when all the y values are 0, you will set max axis value to 100, but you can set it to other value as long as the max axis value is not 0, and the bar chart will shown even if all the y values are 0.
hope it will fix your problem
How do I know what margins to use in an AChartEngine chart to prevent the y-axis labels from being displayed outside the chart when it is set to fill a layout? Can I automatically resize the chart so that the y-axis labels always are visible, even if they contain more than 2-3 digits?
/Markus
You cannot do this automatically, but you can tweak the values until it looks good. You can also rotate the labels when you have several digits values.
This is what I used to deal with Y axis labels that can have differing numbers of digits. Find your max Y value, round it to an int, convert to string and then count the length of the string. The length of the string can be used to calculate a value for the Left margin.
//**** Find max y value of dataset
Ymax = getMaxValue(U_Limit);
if(Ymax < 10){
Ymax = 10;
}else{
Ymax = Ymax*1.1;
}
//**** Find int value of number of digits in max y value
int PLAY_FACTOR = text_label_size*.5 // you may have to play around with this value
int leftMargin = (Double.toString(Math.round(Ymax)).length())*PLAY_FACTOR;
int margins[] = { 26, leftMargin, botMargin, 14 }; // Top,Left,Bottom,Right
renderer.setMargins(margins);
Found a better solution, if you use setYLabelsVerticalPadding with a negative value you can move a little bit down the label... in this way the upper Y label will be visible no matter what.
Hope it helps.