How to send MotionEvents to Android?

Question

I'm trying to develop a Virtual Gamepad but I'm facing lots of problems sending input and event to Android, especially with MotionEvents. I have a device rooted and the app stored in /system/app, required to send events to the system, but I'm not able to receive them in an app that I'm using for tests. Here my code to send a MotionEvent:

 val event = MotionEvent.obtain(
     0,
      SystemClock.uptimeMillis(),
      MotionEvent.ACTION_MOVE,
     sThumbLX.toFloat() / 32000, sThumbLY.toFloat() / 32000 * -1,
     1.0f,
     1.0f,
     0,
     1.0f,
     1.0f,
     3,
     0
 )
 event.source = InputDevice.SOURCE_JOYSTICK
  Timber.v("new thumb event send %s", event.toString())
 instrumentation.sendPointerSync(event)
 event.recycle()

Instead, when I use the real gamepad, I get many events like the following:

2019-09-12 15:29:50.576 4555-4555/it.eng.ds.poc.gamepadtestapplication V/EVENT: Event type [Motion] - x [1.0 y [-0.003921509] event [MotionEvent { action=ACTION_MOVE, actionButton=0, id[0]=0, x[0]=1.0, y[0]=-0.003921509, toolType[0]=TOOL_TYPE_UNKNOWN, buttonState=0, metaState=0, flags=0x0, edgeFlags=0x0, pointerCount=1, historySize=2, eventTime=1437191, downTime=0, deviceId=5, source=0x1000010 }]
2019-09-12 15:29:50.576 4555-4555/it.eng.ds.poc.gamepadtestapplication V/EVENT: Event type [Down] - code [22] event [{KeyEvent { action=ACTION_DOWN, keyCode=KEYCODE_DPAD_RIGHT, scanCode=0, metaState=0, flags=0x400, repeatCount=0, eventTime=1437191, downTime=1437191, deviceId=5, source=0x1000010 }}]
2019-09-12 15:29:51.016 4555-4555/it.eng.ds.poc.gamepadtestapplication V/EVENT: Event type [Motion] - x [0.85882366 y [-0.003921509] event [MotionEvent { action=ACTION_MOVE, actionButton=0, id[0]=0, x[0]=0.85882366, y[0]=-0.003921509, toolType[0]=TOOL_TYPE_UNKNOWN, buttonState=0, metaState=0, flags=0x0, edgeFlags=0x0, pointerCount=1, historySize=0, eventTime=1437627, downTime=0, deviceId=5, source=0x1000010 }]
2019-09-12 15:29:51.036 4555-4555/it.eng.ds.poc.gamepadtestapplication V/EVENT: Event type [Motion] - x [0.27058828 y [-0.003921509] event [MotionEvent { action=ACTION_MOVE, actionButton=0, id[0]=0, x[0]=0.27058828, y[0]=-0.003921509, toolType[0]=TOOL_TYPE_UNKNOWN, buttonState=0, metaState=0, flags=0x0, edgeFlags=0x0, pointerCount=1, historySize=3, eventTime=1437651, downTime=0, deviceId=5, source=0x1000010 }]
2019-09-12 15:29:51.036 4555-4555/it.eng.ds.poc.gamepadtestapplication V/EVENT: Event type [Up] - code [22] event [{KeyEvent { action=ACTION_UP, keyCode=KEYCODE_DPAD_RIGHT, scanCode=0, metaState=0, flags=0x400, repeatCount=0, eventTime=1437651, downTime=1437651, deviceId=5, source=0x1000010 }}]
2019-09-12 15:29:51.056 4555-4555/it.eng.ds.poc.gamepadtestapplication V/EVENT: Event type [Motion] - x [0.003921628 y [-0.003921509] event [MotionEvent { action=ACTION_MOVE, actionButton=0, id[0]=0, x[0]=0.003921628, y[0]=-0.003921509, toolType[0]=TOOL_TYPE_UNKNOWN, buttonState=0, metaState=0, flags=0x0, edgeFlags=0x0, pointerCount=1, historySize=1, eventTime=1437663, downTime=0, deviceId=5, source=0x1000010 }]

I'm following the right way or this is not the correct way to do it?

Thanks.

Answer 1

You are following the right way. You see id[0] in logcat?

1. It's because OS initializes(obtains) its MotionEvent object other way, using more complex one.
2. Your output of gamepad shows coords only for id=0, that means there only one pointer on screen.

Try another method, passing pointerProperties[] and pointerCoords[]. In the arrays you have to specify all the touches you have on screen right now, for all the pointers (including all pointers id). Your output of gamepad shows coords only for id=0, that means there only one pointer on screen.

Also, if you want to see your motionEvent in logcat use logging, or you can override methods onGenericMotionEvent() and onTouchEvent() and you will be able to breakpoint on them and investigate incoming MotionEvent.