shell command to change a tts engine?

[Desmanto]

You can change the default TTS using Action Set System Setting. Select Category Secure and find tts_default_locale. Press save and copy that element, so you have the first action to set it to Ava.

Using this action. After locate the tts_default_locale, you can see the value at there. You just need to find tts. There should be another tts_default_synth, which set the default engine you use, in my case it is vocalizer_e2.tts (the package name of Vocalizer e2). If you have install google TTS, you can try to set the package name here (com.google.android.tts), see if it use it as the default engine.

[liloli]

my cell phone is SMARTISAN T1.
there is no such a item named tts_default_locale, I searched both three catgories.

[liloli]

I give up. Thanks a lot anyway.

[Desmanto]

Seems like your phone use custom android OS. They don't implement the standard TTS from android. If that's the case, probably it will be very difficult to make it work. Unless you can find stock AOSP ROM for your phone and flash it. But that will be very risky, so I don't recommend it.