How to solve Uiautomatorviewer issues: GDK_NATIVE_WINDOWS environment variable is not supported in GTK3

I have typed $ uiautomatorviewer and got the error as

(java:642): Gdk-WARNING **: 00:33:28.349: The GDK_NATIVE_WINDOWS environment variable is not supported in GTK3. See the documentation for gdk_window_ensure_native() on how to get native windows. Exception in thread "main" java.lang.UnsatisfiedLinkError: Could not load SWT library. Reasons:      no swt-cairo-gtk-4919 in java.library.path     no swt-cairo-gtk in java.library.path     Can't load library: /usr/lib/jni/libswt-cairo-gtk-4919.so     Can't load library: /usr/lib/jni/libswt-cairo-gtk.so     Can't load library: /home/checkpoint/.swt/lib/linux/x86_64/libswt-cairo-gtk-4919.so     Can't load library: /home/checkpoint/.swt/lib/linux/x86_64/libswt-cairo-gtk.so  at org.eclipse.swt.internal.Library.loadLibrary(Library.java:334) at org.eclipse.swt.internal.Library.loadLibrary(Library.java:242) at org.eclipse.swt.internal.cairo.Cairo.<clinit>(Cairo.java:28) at org.eclipse.swt.widgets.Display.createDisplay(Display.java:1059) at org.eclipse.swt.widgets.Display.create(Display.java:1025) at org.eclipse.swt.graphics.Device.<init>(Device.java:179) at org.eclipse.swt.widgets.Display.<init>(Display.java:590) at org.eclipse.swt.widgets.Display.<init>(Display.java:581) at org.eclipse.swt.widgets.Display.getDefault(Display.java:2450) at org.eclipse.swt.widgets.Shell.<init>(Shell.java:271) at org.eclipse.swt.widgets.Shell.<init>(Shell.java:370) at org.eclipse.jface.window.Window.createShell(Window.java:487) at org.eclipse.jface.window.Window.create(Window.java:430) at org.eclipse.jface.window.Window.open(Window.java:790) at com.android.uiautomator.UiAutomatorViewer.main(UiAutomatorViewer.java:76) 

Then I have tried the $ export GDK_NATIVE_WINDOWS=true , $ export GDK_NATIVE_WINDOWS=1, then $ export LD_LIBRARY_PATH=/usr/lib/jni , then $ export PATH=./bin:$ PATH .. please to know the steps to open UIautomatorviewer in the Ubuntu 18.04. This is for the Appium + android studio mobile app testing.