Hiding ScrollView stick gives null pointer exception on some devices

Question

I tried setting android:scrollbars="none" attribute of ScrollView but then the problem is while entering information the keypad is up and then if you try to scroll then it dosen't scrolls till end of layout.

I hide the scrollbar stick using below code line inside <ScrollView> tag in a layout

android:scrollbarThumbVertical="@null"

It worked perfectly on Samsung s4 device but on LG it crashed with below exception -

FATAL EXCEPTION: main 
java.lang.NullPointerException
at android.widget.ScrollBarDrawable.setAlpha(ScrollBarDrawable.java: 221)
at android.view.View.onDrawScrollBars(View.java: 11306)
at android.view.View.draw(View.java: 13567)
at android.widget.FrameLayout.draw(FrameLayout.java: 467)
at android.widget.ScrollView.draw(ScrollView.java: 1752)
at android.view.View.getDisplayList(View.java: 12512)
at android.view.View.getDisplayList(View.java: 12556)
at android.view.View.draw(View.java: 13285)
at android.view.ViewGroup.drawChild(ViewGroup.java: 2931)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java: 2801)
at android.view.View.draw(View.java: 13564)
at android.view.View.getDisplayList(View.java: 12512)
at android.view.View.getDisplayList(View.java: 12556)
at android.view.View.draw(View.java: 13285)
at android.view.ViewGroup.drawChild(ViewGroup.java: 2931)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java: 2801)
at android.view.View.draw(View.java: 13564)
at android.widget.FrameLayout.draw(FrameLayout.java: 467)
at android.view.View.getDisplayList(View.java: 12512)
at android.view.View.getDisplayList(View.java: 12556)
at android.view.View.draw(View.java: 13285)
at android.view.ViewGroup.drawChild(ViewGroup.java: 2931)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java: 2801)
at android.view.View.getDisplayList(View.java: 12510)
at android.view.View.getDisplayList(View.java: 12556)
at android.view.View.draw(View.java: 13285)
at android.view.ViewGroup.drawChild(ViewGroup.java: 2931)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java: 2801)
at android.view.View.draw(View.java: 13564)
at android.widget.FrameLayout.draw(FrameLayout.java: 467)
at com.android.internal.policy.impl.PhoneWindow$DecorView.draw(PhoneWindow.java: 2473)
at android.view.HardwareRenderer$GlRenderer.draw(HardwareRenderer.java: 1206)
at android.view.ViewRootImpl.draw(ViewRootImpl.java: 2169)
at android.view.ViewRootImpl.performDraw(ViewRootImpl.java: 2041)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java: 1849)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java: 1009)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java: 4256)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java: 725)
at android.view.Choreographer.doCallbacks(Choreographer.java: 555)
at android.view.Choreographer.doFrame(Choreographer.java: 525)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java: 711)
at android.os.Handler.handleCallback(Handler.java: 615)
at android.os.Handler.dispatchMessage(Handler.java: 92)
at android.os.Looper.loop(Looper.java: 137)
at android.app.ActivityThread.main(ActivityThread.java: 4917)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java: 511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java: 790)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java: 557)
at dalvik.system.NativeStart.main(Native Method)

Whats the reason it works on some device and not all?

Is the only options to do it right is by setting it porgramatically as below -

yourScrollView.setVerticalScrollBarEnabled(false);

Answer 1

The @null value causes the NullPointerException. You can use a transparent drawable instead:

android:scrollbarThumbVertical="@android:color/transparent"