Fragment.getDefaultViewModelProviderFactory() crashes if the Fragment is hosted by a FragmentHostCallback with a null Activity. [153762914]

Fixed

Bug

Status Update

No update yet.

Description

ke...@google.com

created issue #1

Apr 11, 2020 12:29AM

Component used: Fragment
Version used: 1.2.4
Devices/Android versions reproduced on: any

Fragment.getDefaultViewModelProviderFactory() makes a call to requireActivity() in order to obtain an instance of Application. This will fail if the Fragment is hosted in a FragmentHostCallback that doesn't reference an Activity (i.e. its context is not an Activity). getDefaultViewModelProviderFactory() and onCreateContextMenu() (which doesn't make sense for non-Activity Fragments) are the only places requireActivity() is used. Everywhere else uses get/requireContext() or allows getActivity() to return null.
Because Fragments are so prevalent, this makes the entire HasDefaultViewModelProviderFactory interface untrustworthy in codebases that may have non-Activity Fragments.

A simple fix would be to return a NewInstanceFactory() if mFragmentManager is non-null but getActivity() is null. This wouldn't support AndroidViewModels, but other ViewModels would still be able to be instantiated. Expanding SavedStateViewModelFactory to not require an Application would also help since the SavedStateHandler infrastructure doesn't appear to require the Application for anything else. Ideally, the Application would be able to be obtained elsewhere for non-Activity Fragments, but not supporting AndroidViewModels would be an acceptable trade off if that's not possible.

A less ideal solution would be to add another constructor to AndroidViewModels that takes a Context for use when an Application is not available, but that would clutter the API and is probably not worth it.

Comments

il...@google.com <il...@google.com> Apr 13, 2020 08:46PM

Assigned to il...@google.com.

il...@google.com <il...@google.com> Apr 13, 2020 09:53PM

Accepted by il...@google.com.

ap...@google.com <ap...@google.com> #2Apr 13, 2020 11:28PM

Seems to be a DNS problem with systems that have 'obtain DNS server address automatically'. Changed my system to a manual setting and the browser etc now work. SDK 2.2 didn't seem to mind the auto setting though.

il...@google.com <il...@google.com> #3Apr 13, 2020 11:30PM

Marked as fixed.

Could you please describe how/where you changed your system to a manual setting?

ap...@google.com <ap...@google.com> #4Apr 14, 2020 07:56PM

Based on its date, this issue was originally reported before Android 2.3. Because of the many changes that existed in Android 4.x compared to previous versions, it's very likely that this issue doesn't exist in recent versions of Android like 4.2.2 or newer. Because of the high likelihood that this issue is obsolete, it is getting closed automatically by a script, without a human looking at it in detail. If the issue still exists on a Nexus 4 or Nexus 7 running Android 4.2.2 and is not related to Google applications, please open a new report accordingly.

ap...@google.com <ap...@google.com> #5Apr 15, 2020 11:52PM

java.lang.IllegalArgumentException: Unable to locate adb
at com.android.tools.idea.run.editor.DeployTargetPickerDialog.<init>(DeployTargetPickerDialog.java:144)
at com.android.tools.idea.run.editor.ShowChooserTargetProvider.showPrompt(ShowChooserTargetProvider.java:113)
at com.android.tools.idea.run.AndroidRunConfigurationBase.getDeployTarget(AndroidRunConfigurationBase.java:600)
at com.android.tools.idea.run.AndroidRunConfigurationBase.doGetState(AndroidRunConfigurationBase.java:281)
at com.android.tools.idea.run.AndroidRunConfigurationBase.getState(AndroidRunConfigurationBase.java:241)
at com.intellij.execution.runners.ExecutionEnvironment.getState(ExecutionEnvironment.java:158)
at com.intellij.execution.runners.BaseProgramRunner.execute(BaseProgramRunner.java:55)
at com.intellij.execution.runners.BaseProgramRunner.execute(BaseProgramRunner.java:50)
at com.intellij.execution.ProgramRunnerUtil.executeConfigurationAsync(ProgramRunnerUtil.java:92)
at com.intellij.execution.ProgramRunnerUtil.executeConfiguration(ProgramRunnerUtil.java:41)
at com.intellij.execution.impl.ExecutionManagerImpl.restart(ExecutionManagerImpl.java:93)
at com.intellij.execution.impl.ExecutionManagerImpl.access$300(ExecutionManagerImpl.java:44)
at com.intellij.execution.impl.ExecutionManagerImpl$3.run(ExecutionManagerImpl.java:442)
at com.intellij.util.concurrency.QueueProcessor.runSafely(QueueProcessor.java:232)
at com.intellij.util.Alarm$Request.runSafely(Alarm.java:356)
at com.intellij.util.Alarm$Request.run(Alarm.java:343)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at com.intellij.util.concurrency.SchedulingWrapper$MyScheduledFutureTask.run(SchedulingWrapper.java:228)
at com.intellij.openapi.application.TransactionGuardImpl$2.run(TransactionGuardImpl.java:315)
at com.intellij.openapi.application.impl.LaterInvocator$FlushQueue.doRun(LaterInvocator.java:435)
at com.intellij.openapi.application.impl.LaterInvocator$FlushQueue.runNextEvent(LaterInvocator.java:419)
at com.intellij.openapi.application.impl.LaterInvocator$FlushQueue.run(LaterInvocator.java:403)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:762)
at java.awt.EventQueue.access$500(EventQueue.java:98)
at java.awt.EventQueue$3.run(EventQueue.java:715)
at java.awt.EventQueue$3.run(EventQueue.java:709)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:732)
at com.intellij.ide.IdeEventQueue.defaultDispatchEvent(IdeEventQueue.java:755)
at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.java:704)
at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:391)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

Issue 153762914