Rendering issues com.google.android.gms.ads.AdView -

i'm using android studio, after 2 days of search can't resolve this, want use adview project try lot of things still have error @ design time on android studio.

for moment build.gradle file have

android { compilesdkversion 21 buildtoolsversion "21.1.2" .... }

dependencies { compile filetree(dir: 'libs', include: ['*.jar']) compile 'com.google.android.gms:play-services-ads:6.5.87' }

java.lang.classnotfoundexception: com.google.android.gms.internal.cy$a     @ com.android.tools.idea.rendering.renderclassloader.findclass(renderclassloader.java:53)     @ org.jetbrains.android.uipreview.projectclassloader.findclass(projectclassloader.java:56)     @ java.lang.classloader.loadclass(classloader.java:307)     @ java.lang.classloader.loadclass(classloader.java:248)     @ java.lang.classloader.defineclass1(native method)     @ java.lang.classloader.defineclasscond(classloader.java:632)     @ java.lang.classloader.defineclass(classloader.java:616)     @ java.lang.classloader.defineclass(classloader.java:466)     @ com.android.tools.idea.rendering.renderclassloader.loadclassfromjar(renderclassloader.java:93)     @ org.jetbrains.android.uipreview.projectclassloader.loadclassfrommoduleordependency(projectclassloader.java:108)     @ org.jetbrains.android.uipreview.projectclassloader.load(projectclassloader.java:89)     @ com.android.tools.idea.rendering.renderclassloader.findclass(renderclassloader.java:56)     @ org.jetbrains.android.uipreview.projectclassloader.findclass(projectclassloader.java:56)     @ java.lang.classloader.loadclass(classloader.java:307)     @ java.lang.classloader.loadclass(classloader.java:248)     @ com.google.android.gms.internal.bh.<init>(unknown source)     @ com.google.android.gms.internal.bh.<init>(unknown source)     @ com.google.android.gms.internal.bh.<init>(unknown source)     @ com.google.android.gms.ads.adview.<init>(unknown source)     @ sun.reflect.nativeconstructoraccessorimpl.newinstance0(native method)     @ sun.reflect.nativeconstructoraccessorimpl.newinstance(nativeconstructoraccessorimpl.java:39)     @ sun.reflect.delegatingconstructoraccessorimpl.newinstance(delegatingconstructoraccessorimpl.java:27)     @ java.lang.reflect.constructor.newinstance(constructor.java:513)     @ org.jetbrains.android.uipreview.viewloader.createnewinstance(viewloader.java:374)     @ org.jetbrains.android.uipreview.viewloader.loadview(viewloader.java:99)     @ com.android.tools.idea.rendering.layoutlibcallback.loadview(layoutlibcallback.java:172)     @ android.view.bridgeinflater.loadcustomview(bridgeinflater.java:207)     @ android.view.bridgeinflater.createviewfromtag(bridgeinflater.java:132)     @ android.view.layoutinflater.rinflate_original(layoutinflater.java:806)     @ android.view.layoutinflater_delegate.rinflate(layoutinflater_delegate.java:64)     @ android.view.layoutinflater.rinflate(layoutinflater.java:782)     @ android.view.layoutinflater.inflate(layoutinflater.java:504)     @ android.view.layoutinflater.inflate(layoutinflater.java:385)     @ com.android.layoutlib.bridge.impl.rendersessionimpl.inflate(rendersessionimpl.java:400)     @ com.android.layoutlib.bridge.bridge.createsession(bridge.java:332)     @ com.android.ide.common.rendering.layoutlibrary.createsession(layoutlibrary.java:332)     @ com.android.tools.idea.rendering.renderservice$3.compute(renderservice.java:575)     @ com.android.tools.idea.rendering.renderservice$3.compute(renderservice.java:564)     @ com.intellij.openapi.application.impl.applicationimpl.runreadaction(applicationimpl.java:932)     @ com.android.tools.idea.rendering.renderservice.createrendersession(renderservice.java:564)     @ com.android.tools.idea.rendering.renderservice.render(renderservice.java:691)     @ com.intellij.android.designer.designsurface.androiddesignereditorpanel$6.run(androiddesignereditorpanel.java:483)     @ com.intellij.util.ui.update.mergingupdatequeue.execute(mergingupdatequeue.java:320)     @ com.intellij.util.ui.update.mergingupdatequeue.execute(mergingupdatequeue.java:310)     @ com.intellij.util.ui.update.mergingupdatequeue$2.run(mergingupdatequeue.java:254)     @ com.intellij.util.ui.update.mergingupdatequeue.flush(mergingupdatequeue.java:269)     @ com.intellij.util.ui.update.mergingupdatequeue.flush(mergingupdatequeue.java:227)     @ com.intellij.util.ui.update.mergingupdatequeue.run(mergingupdatequeue.java:217)     @ com.intellij.util.concurrency.queueprocessor.runsafely(queueprocessor.java:238)     @ com.intellij.util.alarm$request$1.run(alarm.java:327)     @ java.util.concurrent.executors$runnableadapter.call(executors.java:441)     @ java.util.concurrent.futuretask$sync.innerrun(futuretask.java:303)     @ java.util.concurrent.futuretask.run(futuretask.java:138)     @ java.util.concurrent.threadpoolexecutor$worker.runtask(threadpoolexecutor.java:886)     @ java.util.concurrent.threadpoolexecutor$worker.run(threadpoolexecutor.java:908)     @ java.lang.thread.run(thread.java:662) 

thanks in advance

6.5.87 extremely old version of mobile ads sdk. believe 8.4.0 current release; give 1 try.