Device must be rooted?

[JasonHK]

Can you use an alternative way to achieve this feature? For example adb.

[ipcjs]

Root is required.
Can not use adb to achieve this feature.
see: Is it possible to execute adb commands through my android app? - Stack Overflow
（英语不好，剩下的写中文。。。）
adb是电脑上的命令，手机上是没有adb这个名字的命令的。即使有方法可以调用到，也需要root权限，普通的app不可能有权限去执行adb这么高权限的指令。

[JasonHK]

@ipcjs Oh, I mean using adb to grant permissions.

[ipcjs]

这个应用是通过执行Linux的模拟按键的命令实现的。发送模拟按键需要root权限。

[JasonHK]

Oh, is there a new breakthrough for this function to be able to work without root permission?

[ipcjs]

I plan to add a "WiFi ADB mode" that does not require root permission, but need to manually open WiFi ADB.

[nostromov]

[..] without root permission

ScreenshotTile (NoRoot), https://github.com/cvzi/ScreenshotTile is a fork; and on f-droid:

Screenshot Tile (NoRoot), https://f-droid.org/app/com.github.cvzi.screenshottile

EDIT: Also, I've been unable to find what's preventing from using the hardware buttons for screenshots, is it for reassigning gestures? :o

[ipcjs]

@nostromov good job!

[sengsational]

The non-root version (cvzi/ScreenshotTile#5) suffers with a problem of capturing a black image if the foreground app has precluded screenshots.

Does this version get past that limitation?

[ipcjs]

@sengsational This version has the same effect as using the hardware button.

[cvzi]

FYI:
in API28 (Android 9 Pie) we can do
performGlobalAction(GLOBAL_ACTION_TAKE_SCREENSHOT)
from an accessibility service.
It does the same thing as the hardware buttons.