IssueTracker

Any updates on this issue? I found many more memory leaks and would like to report them but will someone look into them?

Thanks for fixing the leak! There are many more memory leaks in leanback. I am using the following file as a workaround for the memory leaks. (call MemoryLeakFixes.onCreate(this) in Application.onCreate). Could these be fixed as well? If you need more details about a specific memory leak workaround let me know.

package com.superthomaslab.hueessentials

import android.app.Activity
import android.app.Application
import android.os.Bundle
import android.transition.Transition
import android.view.View
import androidx.fragment.app.Fragment
import androidx.fragment.app.FragmentActivity
import androidx.fragment.app.FragmentManager
import androidx.leanback.app.BaseSupportFragment
import androidx.leanback.app.BrandedSupportFragment
import androidx.leanback.app.BrowseSupportFragment
import androidx.leanback.app.DetailsSupportFragment
import androidx.leanback.app.GuidedStepSupportFragment
import androidx.leanback.app.HeadersSupportFragment
import androidx.leanback.app.RowsSupportFragment
import androidx.leanback.widget.GuidanceStylist
import androidx.leanback.widget.VerticalGridView

/**
 * Proguard rules in android/tv/proguard-rules.pro.
 */
object MemoryLeakFixes {

    fun onCreate(app: Application) {
        app.registerActivityLifecycleCallbacks(object : Application.ActivityLifecycleCallbacks {
            override fun onActivityCreated(activity: Activity, savedInstanceState: Bundle?) {
                if (activity !is FragmentActivity) return
                val supportFragmentManager = activity.supportFragmentManager
                supportFragmentManager.registerFragmentLifecycleCallbacks(fragmentCallbacks, true)
            }

            override fun onActivityStarted(activity: Activity) {}

            override fun onActivityResumed(activity: Activity) {}

            override fun onActivityPaused(activity: Activity) {}

            override fun onActivityStopped(activity: Activity) {}

            override fun onActivitySaveInstanceState(activity: Activity, outState: Bundle) {}

            override fun onActivityDestroyed(activity: Activity) {}

        })
    }

    private val fragmentCallbacks = object : FragmentManager.FragmentLifecycleCallbacks() {

        private var verticalGridViews = mutableMapOf<Fragment, VerticalGridView>()

        override fun onFragmentViewCreated(
            fm: FragmentManager,
            f: Fragment,
            v: View,
            savedInstanceState: Bundle?
        ) {
            // BaseRowSupportFragment is not public so check for the subclasses.
            if (f is RowsSupportFragment) {
                verticalGridViews[f] = f.verticalGridView
            } else if (f is HeadersSupportFragment) {
                verticalGridViews[f] = f.verticalGridView
            }
        }

        override fun onFragmentViewDestroyed(fm: FragmentManager, f: Fragment) {
            // Memory leak, clear the adapter from the grid view manually because the
            // adapter instance is leaked in BaseRowSupportFragment.
            verticalGridViews.remove(f)?.adapter = null

            // Memory leak, rootView is not set to null in ProgressBarManager (referenced by BaseSupportFragment).
            if (f is BaseSupportFragment) {
                val progressBarManager = f.progressBarManager
                progressBarManager.hide()
                progressBarManager.setRootView(null)
            }

            if (f is BrowseSupportFragment) {
                // Memory leak, mBrowseFrame is not set to null.
                try {
                    BrowseSupportFragment::class.java.getDeclaredField("mBrowseFrame").apply {
                        isAccessible = true
                        set(f, null)
                    }
                } catch (exception: Exception) {
                    exception.printStackTrace()
                }
                // Memory leak, mScaleFrameLayout is not set to null.
                try {
                    BrowseSupportFragment::class.java.getDeclaredField("mScaleFrameLayout").apply {
                        isAccessible = true
                        set(f, null)
                    }
                } catch (exception: Exception) {
                    exception.printStackTrace()
                }
                // Memory leak, mSceneWithHeaders (has reference to mBrowseFrame) is not set to null.
                try {
                    BrowseSupportFragment::class.java.getDeclaredField("mSceneWithHeaders").apply {
                        isAccessible = true
                        set(f, null)
                    }
                } catch (exception: Exception) {
                    exception.printStackTrace()
                }
                // Memory leak, mSceneWithoutHeaders (has reference to mBrowseFrame) is not set to null.
                try {
                    BrowseSupportFragment::class.java.getDeclaredField("mSceneWithoutHeaders").apply {
                        isAccessible = true
                        set(f, null)
                    }
                } catch (exception: Exception) {
                    exception.printStackTrace()
                }
                // Memory leak, mSceneAfterEntranceTransition (has reference to mBrowseFrame) is not set to null.
                try {
                    BrowseSupportFragment::class.java.getDeclaredField("mSceneAfterEntranceTransition").apply {
                        isAccessible = true
                        set(f, null)
                    }
                } catch (exception: Exception) {
                    exception.printStackTrace()
                }
            }

            // Memory leak, mGuidanceContainer is not set to null.
            // https://issuetracker.google.com/issues/164841457
            if (f is GuidedStepSupportFragment) {
                try {
                    GuidanceStylist::class.java.getDeclaredField("mGuidanceContainer").apply {
                        isAccessible = true
                        set(f.guidanceStylist, null)
                    }
                } catch (exception: Exception) {
                    exception.printStackTrace()
                }
            }

            // Memory leak, mTitleView is not set to null.
            if (f is BrandedSupportFragment) {
                f.titleView = null
            }
        }

        override fun onFragmentDestroyed(fm: FragmentManager, f: Fragment) {
            // Memory leak, the transition listeners (with references to the fragment) are added to the
            // activity window but never removed, so remove them manually in the Frament onDestroy.
            if (f is DetailsSupportFragment) {
                fun removeTransitionListener(fieldName: String, activityTransition: Transition) {
                    try {
                        val transitionListener = DetailsSupportFragment::class.java
                            .getDeclaredField(fieldName).let {
                                it.isAccessible = true
                                it.get(f)
                            }
                        transitionListener::class.java.superclass!!.getDeclaredField("mImpl").apply {
                            isAccessible = true
                            val implValue = get(transitionListener) as Transition.TransitionListener?
                            if (implValue != null) {
                                activityTransition.removeListener(implValue)

                                set(transitionListener, null)
                            }
                        }
                    } catch (exception: Exception) {
                        exception.printStackTrace()
                    }
                }

                val window = f.requireActivity().window
                removeTransitionListener("mEnterTransitionListener", window.enterTransition)
                removeTransitionListener("mReturnTransitionListener", window.returnTransition)
            }
        }
    }
}

Thanks for the explanation!

I am using the leanback fragments (including BrowseSupportFragment) in a single Activity. I did that primarily because a single Activity is recommended by Google. Furthermore, the Leanback sample app also uses a single Activity (https://github.com/android/tv-samples/tree/master/ClassicsKotlin). Could you please reconsider fixing this?