Appium error 'Cannot read property 'shell' of null' raised during driver.getScreenshotAs(xxx) method call

[Mague]

Hi everybody,

I don't understand why this error message 'ERROR running Appium command: Cannot read property 'shell' of null' is raised during this method call:
File scrFile2 = ((TakesScreenshot)driver).getScreenshotAs(OutputType.FILE);

Context: 'getScreenshotAs' method is called just after a closeApp() method.
If i do
((TakesScreenshot)driver).getScreenshotAs(OutputType.FILE);
before the 'closeApp()' method call, no error is raised. The test works fine.

My current code:
....
File scrFile1= ((TakesScreenshot)driver).getScreenshotAs(OutputType.FILE);
driver.closeApp();
File scrFile2 = ((TakesScreenshot)driver).getScreenshotAs(OutputType.FILE);
....

Thanks you in advance for your help

[email2vimalraj]

@Mague: What version of appium server are you using?
In the earlier version of appium server, the closeApp goes through the shutdown cycle. But from v1.5.x, it has changed. Kindly verify.

[Mague]

Thanks you @email@vimalraj, my Appium version is 1.4.13.

[afwang]

IIRC, closeApp also destroys and cleans up the driver session, so if you take a screenshot after calling closeApp, you'll run into an error.

If you need to return to the home screen before taking a screenshot, you can send in the Android keycode the Android home button. Check the Appium Javadocs for the constant representing the home key.