scrcpy/server
Romain Vimont 40febf4a91 Use device id 0 for touch/mouse events
Virtual device is only for keyboard sources, not mouse or touchscreen
sources. Here is the value of InputDevice.getDevice(-1).toString():

    Input Device -1: Virtual
      Descriptor: ...
      Generation: 2
      Location: built-in
      Keyboard Type: alphabetic
      Has Vibrator: false
      Has mic: false
      Sources: 0x301 ( keyboard dpad )

InputDevice.getDeviceId() documentation says:

> An id of zero indicates that the event didn't come from a physical
> device and maps to the default keymap.

<https://developer.android.com/reference/android/view/InputEvent#getDeviceId()>

However, injecting events with a device id of 0 causes event.getDevice()
to be null on the client-side.

Commit 26529d377f used -1 as a workaround
to avoid a NPE on a specific Android TV device. But this is a bug in the
device system, which wrongly assumes that input device may not be null.

A similar issue was present in Flutter, but it is now fixed:
 - <https://github.com/flutter/flutter/issues/30665>
 - <https://github.com/flutter/engine/pull/7986>

On the other hand, using an id of -1 for touchscreen events (which is
invalid) causes issues for some apps:
<https://github.com/Genymobile/scrcpy/issues/2125#issuecomment-790535792>

Therefore, use a device id of 0.

An alternative could be to find an existing device matching the source,
like "adb shell input" does. See getInputDeviceId():
<https://android.googlesource.com/platform/frameworks/base.git/+/master/cmds/input/src/com/android/commands/input/Input.java>

But it seems better to indicate that the event didn't come from a
physical device, and it would not solve #962 anyway, because an Android
TV has no touchscreen.

Refs #962 <https://github.com/Genymobile/scrcpy/issues/962>
Fixes #2125 <https://github.com/Genymobile/scrcpy/issues/2125>
2021-03-14 18:30:56 +01:00
..
scripts Use "/usr/bin/env bash" for build-wrapper.sh 2020-09-15 13:44:02 +02:00
src Use device id 0 for touch/mouse events 2021-03-14 18:30:56 +01:00
.gitignore Convert server to an Android project 2018-01-30 12:01:36 +01:00
build.gradle Bump version to 1.17 2021-01-02 00:53:32 +01:00
build_without_gradle.sh Bump version to 1.17 2021-01-02 00:53:32 +01:00
meson.build Require Meson 0.48 to get rid of warnings 2020-04-13 22:47:03 +02:00
proguard-rules.pro Convert server to an Android project 2018-01-30 12:01:36 +01:00