Logcat System.err message

Question

So as soon as I boot up my device and then use:

adb -d logcat | grep System.err

The device is rooted and I had my application installed. Even after removing all applications (except Terminal Emulator which I doubt will have any effect as its not on boot) I still get this error. Is it something I should be concerned about?

I get the following error messages:

W/System.err( 1085): java.lang.Throwable
W/System.err( 1085):    at com.android.launcher3.Workspace.addInScreen(Workspace.java:811)
W/System.err( 1085):    at com.android.launcher3.Workspace.addInScreenFromBind(Workspace.java:781)
W/System.err( 1085):    at com.android.launcher3.Launcher.bindItems(Launcher.java:3720)
W/System.err( 1085):    at com.android.launcher3.LauncherModel$LoaderTask$5.run(LauncherModel.java:2148)
W/System.err( 1085):    at com.android.launcher3.DeferredHandler$Impl.handleMessage(DeferredHandler.java:50)
W/System.err( 1085):    at android.os.Handler.dispatchMessage(Handler.java:102)
W/System.err( 1085):    at android.os.Looper.loop(Looper.java:136)
W/System.err( 1085):    at android.app.ActivityThread.main(ActivityThread.java:5017)
W/System.err( 1085):    at java.lang.reflect.Method.invokeNative(Native Method)
W/System.err( 1085):    at java.lang.reflect.Method.invoke(Method.java:515)
W/System.err( 1085):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
W/System.err( 1085):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
W/System.err( 1085):    at dalvik.system.NativeStart.main(Native Method)

Answer 1

It's hard to say why does it happen, but I think you don't need to worry about that. The source code of Workspace.java can be found here and error is pointing to the following piece of code:

if (getScreenWithId(screenId) == null) {
    Log.e(TAG, "Skipping child, screenId " + screenId + " not found");
    // DEBUGGING - Print out the stack trace to see where we are adding from
    new Throwable().printStackTrace();
    return;
}

And the getScreenWithId method:

public CellLayout getScreenWithId(long screenId) {
    CellLayout layout = mWorkspaceScreens.get(screenId);
    return layout;
}

So, it can give the basic idea to investigate why does it happen.