How to not draw zero values on a linechart while showing their X axis values on MPAndroidChart?

Question

I'm using MPAndroidChart to display my data in a line graph. For each date I have its own value.

This works just fine. What I want to do now is to not draw the 0 values, but instead draw the line between 2 adjacent non-zero values (like a trend-line), while keep showing the dates on the x-axis for the zero values.

My current graph:

The desired graph should look similar to this graph:

How can I achieve this behavior?

Answer 1

I'm posting my friend's solution here (worked like a charm):

1. Create a dataset with 0 values. Draw it but with line of transparent color.
2. Create a dataset without 0. Draw it with the color that you need.

Put (1) and (2) on the same LineChart.

It will give you an x axis with x values where there are 0 values but will not draw a line for them.

The second dataset will show the line of data points without the 0 values.

Answer 2

Without drawing two lines like limlim suggested, you have to add only non zero values to your entries, but the x value has to be incremented anyway:

List<SomeClass> values = new ArrayList<>();

int k = 0;
List<Entry> entries = new ArrayList<>();
for (SomeClass v : values){
  if (v.value > 0){
    entries.add(new Entry(k, v.value));
  }
  k += 1;
}

Answer 3

There is no need to split dataset to draw empty points for MPAndroidChart:v3.1.0. All you have to do is set those empty points value as Float.NaN (in case of Kotlin).