How to call a calendar in my application using intentions?

You will need Intentone that looks something like this:

Intent calendarIntent = new Intent(Intent.ACTION_EDIT);  
calendarIntent.setType("vnd.android.cursor.item/event");
calendarIntent.putExtra("title", "Title");
calendarIntent.putExtra("beginTime", startTimeMillis);
calendarIntent.putExtra("endTime", endTimeMillis);
calendarIntent.putExtra("description", "Description");

Then you can run it by calling this:

startActivity(calendarIntent);