Merge pull request #724 from NotWoods/viewmodel-no-leak

Remove HomeViewModel memory leak

app/src/main/java/com/vanced/manager/adapter/ExpandableAppListAdapter.kt

@@ -84,10 +84,12 @@ class ExpandableAppListAdapter(
                     appDownload.apply {
                         setOnClickListener {
                             viewModel.openInstallDialog(
+                                activity.supportFragmentManager,
                                 buttonTag,
                                 apps[position]
                             )
                         }
+                        appDownload.setIconResource(buttonTag.image)
                         contentDescription = activity.getString(
                             when (buttonTag) {
                                 ButtonTag.UPDATE -> R.string.accessibility_update
@@ -108,11 +110,6 @@ class ExpandableAppListAdapter(
                 dataModel?.installedVersionName?.observe(activity) {
                     appVersionInstalled.text = it
                 }
-                dataModel?.buttonImage?.observe(activity) {
-                    if (it != null) {
-                        appDownload.icon = it
-                    }
-                }
             }
         }
     }

app/src/main/java/com/vanced/manager/adapter/LinkAdapter.kt

@@ -64,7 +64,7 @@ class LinkAdapter(
 
         fun bind(position: Int) {
             binding.linkBg.setOnClickListener {
-                viewModel.openUrl(links[position].linkUrl)
+                viewModel.openUrl(context, links[position].linkUrl)
             }
         }
     }

app/src/main/java/com/vanced/manager/adapter/SponsorAdapter.kt

@@ -42,7 +42,7 @@ class SponsorAdapter(
             with(binding) {
                 sponsorName.text = sponsors[position].name
                 cardSponsor.setOnClickListener {
-                    viewModel.openUrl(sponsors[position].url)
+                    viewModel.openUrl(context, sponsors[position].url)
                 }
             }
         }

app/src/main/java/com/vanced/manager/core/CombinedLiveData.kt

@@ -0,0 +1,37 @@
+package com.vanced.manager.core
+
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MediatorLiveData
+
+/**
+ * CombinedLiveData is a helper class to combine results from two LiveData sources.
+ * @param combine   Function reference that will be used to combine all LiveData data.
+ * @param R         The type of data returned after combining all LiveData data.
+ * Usage:
+ * CombinedLiveData(
+ *     getLiveData1(),
+ *     getLiveData2()
+ * ) { data1, data2 ->
+ *     // Use datas[0], datas[1], ..., datas[N] to return a value
+ * }
+ */
+class CombinedLiveData<R, A, B>(
+    liveDataA: LiveData<A>,
+    liveDataB: LiveData<B>,
+    private val combine: (a: A?, b: B?) -> R
+) : MediatorLiveData<R>() {
+
+    private var a: A? = null
+    private var b: B? = null
+
+    init {
+        addSource(liveDataA) {
+            a = it
+            value = combine(a, b)
+        }
+        addSource(liveDataB) {
+            b = it
+            value = combine(a, b)
+        }
+    }
+}

app/src/main/java/com/vanced/manager/model/ButtonTag.kt

@@ -1,5 +1,10 @@
 package com.vanced.manager.model
 
-enum class ButtonTag {
-    INSTALL, UPDATE, REINSTALL
+import androidx.annotation.DrawableRes
+import com.vanced.manager.R
+
+enum class ButtonTag(@DrawableRes val image: Int) {
+    INSTALL(R.drawable.ic_app_download),
+    UPDATE(R.drawable.ic_app_update),
+    REINSTALL(R.drawable.ic_app_reinstall)
 }

app/src/main/java/com/vanced/manager/model/DataModel.kt

@@ -5,63 +5,46 @@ import android.graphics.drawable.Drawable
 import android.os.Build
 import androidx.annotation.DrawableRes
 import androidx.core.content.ContextCompat
-import androidx.lifecycle.LifecycleOwner
-import androidx.lifecycle.LiveData
-import androidx.lifecycle.MutableLiveData
+import androidx.lifecycle.*
 import com.beust.klaxon.JsonObject
 import com.vanced.manager.R
+import com.vanced.manager.core.CombinedLiveData
 import com.vanced.manager.utils.PackageHelper.isPackageInstalled
 
 open class DataModel(
-    private val jsonObject: LiveData<JsonObject?>,
-    private val context: Context,
-    lifecycleOwner: LifecycleOwner,
+    jsonObject: LiveData<JsonObject?>,
+    context: Context,
     val appPkg: String,
     val appName: String,
     val appDescription: String,
     @DrawableRes val appIcon: Int
 ) {
 
-    private val versionCode = MutableLiveData<Int>()
-    private val installedVersionCode = MutableLiveData<Int>()
+    val isAppInstalled = Transformations.map(jsonObject) { isAppInstalled(appPkg) }
+
+    private val versionCode = Transformations.map(jsonObject) { jobj ->
+        jobj?.int("versionCode") ?: 0
+    }
+    private val installedVersionCode = Transformations.map(isAppInstalled) {
+        getPkgVersionCode(appPkg, it)
+    }
     private val unavailable = context.getString(R.string.unavailable)
     private val pm = context.packageManager
 
-    val isAppInstalled = MutableLiveData<Boolean>()
-    val versionName = MutableLiveData<String>()
-    val installedVersionName = MutableLiveData<String>()
-    val buttonTag = MutableLiveData<ButtonTag>()
-    val buttonImage = MutableLiveData<Drawable>()
-    val changelog = MutableLiveData<String>()
-
-    private fun fetch() {
-        val jobj = jsonObject.value
-        isAppInstalled.value = isAppInstalled(appPkg)
-        versionCode.value = jobj?.int("versionCode") ?: 0
-        versionName.value = jobj?.string("version") ?: unavailable
-        changelog.value = jobj?.string("changelog") ?: unavailable
+    val versionName = Transformations.map(jsonObject) { jobj ->
+        jobj?.string("version") ?: unavailable
     }
-
-    init {
-        fetch()
-        with(lifecycleOwner) {
-            jsonObject.observe(this) {
-                fetch()
-            }
-            isAppInstalled.observe(this) {
-                installedVersionCode.value = getPkgVersionCode(appPkg, it)
-                installedVersionName.value = getPkgVersionName(appPkg, it)
-            }
-            versionCode.observe(this) { versionCode ->
-                installedVersionCode.observe(this) { installedVersionCode ->
-                    buttonTag.value = compareInt(installedVersionCode, versionCode)
-                    buttonImage.value = compareIntDrawable(installedVersionCode, versionCode)
-                }
-            }
-        }
+    val changelog = Transformations.map(jsonObject) { jobj ->
+        jobj?.string("changelog") ?: unavailable
+    }
+    val installedVersionName = Transformations.map(isAppInstalled) {
+        getPkgVersionName(appPkg, it)
+    }
+    val buttonTag = CombinedLiveData(versionCode, installedVersionCode) { versionCode, installedVersionCode ->
+        compareInt(installedVersionCode, versionCode)
     }
 
-    open fun isAppInstalled(pkg: String): Boolean = isPackageInstalled(pkg, context.packageManager)
+    open fun isAppInstalled(pkg: String): Boolean = isPackageInstalled(pkg, pm)
 
     private fun getPkgVersionName(pkg: String, isAppInstalled: Boolean): String {
         return if (isAppInstalled) {
@@ -95,16 +78,4 @@ open class DataModel(
         }
         return ButtonTag.INSTALL
     }
-
-    private fun compareIntDrawable(int1: Int?, int2: Int?): Drawable {
-        if (int2 != null && int1 != null) {
-            return when {
-                int1 == 0 -> ContextCompat.getDrawable(context, R.drawable.ic_app_download)!!
-                int2 > int1 -> ContextCompat.getDrawable(context, R.drawable.ic_app_update)!!
-                int1 >= int2 -> ContextCompat.getDrawable(context, R.drawable.ic_app_reinstall)!!
-                else -> ContextCompat.getDrawable(context, R.drawable.ic_app_download)!!
-            }
-        }
-        return ContextCompat.getDrawable(context, R.drawable.ic_app_download)!!
-    }
 }

app/src/main/java/com/vanced/manager/model/RootDataModel.kt

@@ -10,7 +10,6 @@ import com.vanced.manager.utils.PackageHelper
 class RootDataModel(
     jsonObject: LiveData<JsonObject?>,
     context: Context,
-    lifecycleOwner: LifecycleOwner,
     appPkg: String,
     appName: String,
     appDescription: String,
@@ -22,7 +21,7 @@ class RootDataModel(
     //Ironic, isn't it?
     private val scriptName: String?
 ) : DataModel(
-    jsonObject, context, lifecycleOwner, appPkg, appName, appDescription, appIcon
+    jsonObject, context, appPkg, appName, appDescription, appIcon
 ) {
 
     override fun isAppInstalled(pkg: String): Boolean {

app/src/main/java/com/vanced/manager/ui/fragments/HomeFragment.kt

@@ -26,7 +26,6 @@ import com.vanced.manager.databinding.FragmentHomeBinding
 import com.vanced.manager.ui.dialogs.AppInfoDialog
 import com.vanced.manager.ui.dialogs.DialogContainer.installAlertBuilder
 import com.vanced.manager.ui.viewmodels.HomeViewModel
-import com.vanced.manager.ui.viewmodels.HomeViewModelFactory
 import com.vanced.manager.utils.isFetching
 import com.vanced.manager.utils.manager
 
@@ -37,9 +36,7 @@ class HomeFragment : BindingFragment<FragmentHomeBinding>() {
         const val REFRESH_HOME = "REFRESH_HOME"
     }
 
-    private val viewModel: HomeViewModel by viewModels {
-        HomeViewModelFactory(requireActivity())
-    }
+    private val viewModel: HomeViewModel by viewModels()
 
     private val localBroadcastManager by lazy { LocalBroadcastManager.getInstance(requireActivity()) }