Thank you RickG!
I’m using the board designed by MATT.I have cut the trace from gpio 12 and then solder a small wire from gpio 33 to the enable pin trace on the board as what you said.But now just one stepper is working,the other one is no power.Can you help me?Thang you very much!
I used The 4.1.3 verion downloaded from https://developer.android.google.cn/studio/. And you must select “File-Settings-System settings-Andriod Sdk”，and tick off “Andriod 9.0（Pie）”,then you cancompile the code I think.You can have a try.
Thanks for your reply,I have packed and signed the code and got a .apk file.Then I installed it on my phone. It can be opened but it quit unexpectedly when I touched the botton.My phone type is HUAWEI,I don’t know why.