2.6. Start with the LVGL GUI Simulation Project

The LVGL GUI Simulation Project provides an experimental environment for co-simulation of PikaPython and LVGL.

The GUI simulation can be performed on a PC using Visual Studio.

2.6.1. Get the project

http://pikascript.com/

Select lvgl-vs-simu, a Visual Studio simulation project, from the Project Builder on the official PikaPython website.

This project is branched from the official LVGL Visual Studio simulation project.

Click Generate Project and wait about 1 minute.

Unzip the project and open LVGL.Simulator.sln

Start compiling and running directly

You can see that the lvgl emulator has been successfully started

2.6.2. Programming with Python

The Python file for running the project is in LVGL.Simulator/pikascript/main.py, and it is recommended to edit the Python file with VSCode.

The code in main.py is shown below, and the project will run this main.py when it starts

# main.py
import pika_lvgl as lv
import PikaStdLib
mem = PikaStdLib.MemChecker()

# Create an Arc
arc = lv.arc(lv.scr_act())
arc.set_end_angle(200)
arc.set_size(150, 150)
arc.center()

print('mem used max: %0.2f kB' % (mem.getMax()))
print('mem used now: %0.2f kB' % (mem.getNow()))

More sample code

You can see more sample code in the /pikascript/examples/lvgl folder.

For example, you can copy lv_callback1.py into main.py.

# lv_callback1.py
import pika_lvgl as lv
import PikaStdLib
mem = PikaStdLib.MemChecker()


def event_cb_1(evt):
    print('in evt1')
    print('mem used now: %0.2f kB' % (mem.getNow()))


def event_cb_2(evt):
    print('in evt2')
    print('mem used now: %0.2f kB' % (mem.getNow()))


btn1 = lv.btn(lv.scr_act())
btn1.align(lv.ALIGN.TOP_MID, 0, 10)
btn2 = lv.btn(lv.scr_act())
btn2.align(lv.ALIGN.TOP_MID, 0, 50)
btn1.add_event_cb(event_cb_1, lv.EVENT.CLICKED, 0)
btn2.add_event_cb(event_cb_2, lv.EVENT.CLICKED, 0)

print('mem used max: %0.2f kB' % (mem.getMax()))
print('mem used now: %0.2f kB' % (mem.getNow()))

After replacing main.py, run PikaPython’s pre-compiler

and then start running

In this example you can click the button and then view the output.

2.6.3. Frequently Asked Questions

If you are prompted for missing functions, you need to manually add the files to be compiled

Right-click on pikascript/pikascript-api and pikascript/pikascript-lib and click “Include in project”, then recompile.