I have attached the screenshot of my usage chart. In red box display the legends and they are cutting in pie chart. Below is my code:
Most probably there is an issue with the chart offsets. Try this, should solve your problem
pieChart.setExtraOffsets(0, 0, 0, 25);
This function sets extra offsets (around the chart view) to be appended to the auto-calculated offsets. The arguments are (left, top, right, bottom). Play around with the values to see which offsets suits your needs.