Move coroutine job into its own class

app/src/main/java/com/topjohnwu/magisk/arch/AsyncLoadViewModel.kt

@@ -0,0 +1,22 @@
+package com.topjohnwu.magisk.arch
+
+import androidx.annotation.MainThread
+import androidx.lifecycle.viewModelScope
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.launch
+
+abstract class AsyncLoadViewModel : BaseViewModel() {
+
+    private var loadingJob: Job? = null
+
+    @MainThread
+    fun startLoading() {
+        if (loadingJob?.isActive == true) {
+            // Prevent multiple jobs from running at the same time
+            return
+        }
+        loadingJob = viewModelScope.launch { doLoadWork() }
+    }
+
+    protected abstract suspend fun doLoadWork()
+}

app/src/main/java/com/topjohnwu/magisk/arch/BaseFragment.kt

@@ -76,7 +76,10 @@ abstract class BaseFragment<Binding : ViewDataBinding> : Fragment(), ViewModelHo
 
     override fun onResume() {
         super.onResume()
-        viewModel.requestRefresh()
+        viewModel.let {
+            if (it is AsyncLoadViewModel)
+                it.startLoading()
+        }
     }
 
     protected open fun onPreBind(binding: Binding) {

app/src/main/java/com/topjohnwu/magisk/arch/BaseViewModel.kt

@@ -16,31 +16,16 @@ import com.topjohnwu.magisk.events.BackPressEvent
 import com.topjohnwu.magisk.events.NavigationEvent
 import com.topjohnwu.magisk.events.PermissionEvent
 import com.topjohnwu.magisk.events.SnackbarEvent
-import kotlinx.coroutines.Job
 
 abstract class BaseViewModel : ViewModel(), ObservableHost {
 
     override var callbacks: PropertyChangeRegistry? = null
 
-    val viewEvents: LiveData<ViewEvent> get() = _viewEvents
-
     private val _viewEvents = MutableLiveData<ViewEvent>()
-    private var runningJob: Job? = null
+    val viewEvents: LiveData<ViewEvent> get() = _viewEvents
 
     open fun onSaveState(state: Bundle) {}
     open fun onRestoreState(state: Bundle) {}
-
-    /** This should probably never be called manually, it's called manually via delegate. */
-    @Synchronized
-    fun requestRefresh() {
-        if (runningJob?.isActive == true) {
-            return
-        }
-        runningJob = refresh()
-    }
-
-    protected open fun refresh(): Job? = null
-
     open fun onNetworkChanged(network: Boolean) {}
 
     fun withPermission(permission: String, callback: (Boolean) -> Unit) {

app/src/main/java/com/topjohnwu/magisk/arch/UIActivity.kt

@@ -89,7 +89,10 @@ abstract class UIActivity<Binding : ViewDataBinding> : BaseActivity(), ViewModel
 
     override fun onResume() {
         super.onResume()
-        viewModel.requestRefresh()
+        viewModel.let {
+            if (it is AsyncLoadViewModel)
+                it.startLoading()
+        }
     }
 
     override fun onEventDispatched(event: ViewEvent) = when (event) {

app/src/main/java/com/topjohnwu/magisk/ui/deny/DenyListViewModel.kt

@@ -3,9 +3,8 @@ package com.topjohnwu.magisk.ui.deny
 import android.annotation.SuppressLint
 import android.content.pm.PackageManager.MATCH_UNINSTALLED_PACKAGES
 import androidx.databinding.Bindable
-import androidx.lifecycle.viewModelScope
 import com.topjohnwu.magisk.BR
-import com.topjohnwu.magisk.arch.BaseViewModel
+import com.topjohnwu.magisk.arch.AsyncLoadViewModel
 import com.topjohnwu.magisk.core.di.AppContext
 import com.topjohnwu.magisk.databinding.bindExtra
 import com.topjohnwu.magisk.databinding.filterableListOf
@@ -16,10 +15,9 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.asFlow
 import kotlinx.coroutines.flow.filter
 import kotlinx.coroutines.flow.toCollection
-import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 
-class DenyListViewModel : BaseViewModel() {
+class DenyListViewModel : AsyncLoadViewModel() {
 
     var isShowSystem = false
         set(value) {
@@ -49,7 +47,7 @@ class DenyListViewModel : BaseViewModel() {
         private set(value) = set(value, field, { field = it }, BR.loading)
 
     @SuppressLint("InlinedApi")
-    override fun refresh() = viewModelScope.launch {
+    override suspend fun doLoadWork() {
         loading = true
         val (apps, diff) = withContext(Dispatchers.Default) {
             val pm = AppContext.packageManager

app/src/main/java/com/topjohnwu/magisk/ui/home/HomeViewModel.kt

@@ -3,7 +3,6 @@ package com.topjohnwu.magisk.ui.home
 import android.content.Context
 import androidx.core.net.toUri
 import androidx.databinding.Bindable
-import androidx.lifecycle.viewModelScope
 import com.topjohnwu.magisk.BR
 import com.topjohnwu.magisk.BuildConfig
 import com.topjohnwu.magisk.R
@@ -23,12 +22,11 @@ import com.topjohnwu.magisk.ktx.await
 import com.topjohnwu.magisk.utils.Utils
 import com.topjohnwu.magisk.utils.asText
 import com.topjohnwu.superuser.Shell
-import kotlinx.coroutines.launch
 import kotlin.math.roundToInt
 
 class HomeViewModel(
     private val svc: NetworkService
-) : BaseViewModel() {
+) : AsyncLoadViewModel() {
 
     enum class State {
         LOADING, INVALID, OUTDATED, UP_TO_DATE
@@ -83,7 +81,7 @@ class HomeViewModel(
         private var checkedEnv = false
     }
 
-    override fun refresh() = viewModelScope.launch {
+    override suspend fun doLoadWork() {
         appState = State.LOADING
         Info.getRemote(svc)?.apply {
             appState = when {
@@ -101,9 +99,7 @@ class HomeViewModel(
         ensureEnv()
     }
 
-    override fun onNetworkChanged(network: Boolean) {
-        requestRefresh()
-    }
+    override fun onNetworkChanged(network: Boolean) = startLoading()
 
     fun onProgressUpdate(progress: Float, subject: Subject) {
         if (subject is App)

app/src/main/java/com/topjohnwu/magisk/ui/log/LogViewModel.kt

@@ -5,7 +5,7 @@ import androidx.lifecycle.viewModelScope
 import com.topjohnwu.magisk.BR
 import com.topjohnwu.magisk.BuildConfig
 import com.topjohnwu.magisk.R
-import com.topjohnwu.magisk.arch.BaseViewModel
+import com.topjohnwu.magisk.arch.AsyncLoadViewModel
 import com.topjohnwu.magisk.core.Info
 import com.topjohnwu.magisk.core.repository.LogRepository
 import com.topjohnwu.magisk.core.utils.MediaStoreUtils
@@ -24,7 +24,7 @@ import java.io.FileInputStream
 
 class LogViewModel(
     private val repo: LogRepository
-) : BaseViewModel() {
+) : AsyncLoadViewModel() {
 
     // --- empty view
 
@@ -43,7 +43,7 @@ class LogViewModel(
     var consoleText = " "
         set(value) = set(value, field, { field = it }, BR.consoleText)
 
-    override fun refresh() = viewModelScope.launch {
+    override suspend fun doLoadWork() {
         consoleText = repo.fetchMagiskLogs()
         val (suLogs, diff) = withContext(Dispatchers.Default) {
             val suLogs = repo.fetchSuLogs().map { LogRvItem(it) }
@@ -89,12 +89,12 @@ class LogViewModel(
 
     fun clearMagiskLog() = repo.clearMagiskLogs {
         SnackbarEvent(R.string.logs_cleared).publish()
-        requestRefresh()
+        startLoading()
     }
 
     fun clearLog() = viewModelScope.launch {
         repo.clearLogs()
         SnackbarEvent(R.string.logs_cleared).publish()
-        requestRefresh()
+        startLoading()
     }
 }

app/src/main/java/com/topjohnwu/magisk/ui/module/ModuleViewModel.kt

@@ -3,10 +3,9 @@ package com.topjohnwu.magisk.ui.module
 import android.net.Uri
 import androidx.databinding.Bindable
 import androidx.lifecycle.MutableLiveData
-import androidx.lifecycle.viewModelScope
 import com.topjohnwu.magisk.BR
 import com.topjohnwu.magisk.R
-import com.topjohnwu.magisk.arch.BaseViewModel
+import com.topjohnwu.magisk.arch.AsyncLoadViewModel
 import com.topjohnwu.magisk.core.Info
 import com.topjohnwu.magisk.core.base.ContentResultCallback
 import com.topjohnwu.magisk.core.model.module.LocalModule
@@ -16,12 +15,10 @@ import com.topjohnwu.magisk.events.GetContentEvent
 import com.topjohnwu.magisk.events.SnackbarEvent
 import com.topjohnwu.magisk.events.dialog.ModuleInstallDialog
 import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.Job
-import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import kotlinx.parcelize.Parcelize
 
-class ModuleViewModel : BaseViewModel() {
+class ModuleViewModel : AsyncLoadViewModel() {
 
     val bottomBarBarrierIds = intArrayOf(R.id.module_update, R.id.module_remove)
 
@@ -45,18 +42,14 @@ class ModuleViewModel : BaseViewModel() {
         }
     }
 
-    override fun refresh(): Job {
-        return viewModelScope.launch {
-            loading = true
-            loadInstalled()
-            loading = false
-            loadUpdateInfo()
-        }
+    override suspend fun doLoadWork() {
+        loading = true
+        loadInstalled()
+        loading = false
+        loadUpdateInfo()
     }
 
-    override fun onNetworkChanged(network: Boolean) {
-        requestRefresh()
-    }
+    override fun onNetworkChanged(network: Boolean) = startLoading()
 
     private suspend fun loadInstalled() {
         val installed = LocalModule.installed().map { LocalModuleRvItem(it) }

app/src/main/java/com/topjohnwu/magisk/ui/superuser/SuperuserViewModel.kt

@@ -9,7 +9,7 @@ import androidx.databinding.ObservableArrayList
 import androidx.lifecycle.viewModelScope
 import com.topjohnwu.magisk.BR
 import com.topjohnwu.magisk.R
-import com.topjohnwu.magisk.arch.BaseViewModel
+import com.topjohnwu.magisk.arch.AsyncLoadViewModel
 import com.topjohnwu.magisk.core.data.magiskdb.PolicyDao
 import com.topjohnwu.magisk.core.di.AppContext
 import com.topjohnwu.magisk.core.model.su.SuPolicy
@@ -29,7 +29,7 @@ import kotlinx.coroutines.withContext
 
 class SuperuserViewModel(
     private val db: PolicyDao
-) : BaseViewModel() {
+) : AsyncLoadViewModel() {
 
     private val itemNoData = TextItem(R.string.superuser_policy_none)
 
@@ -48,10 +48,10 @@ class SuperuserViewModel(
         private set(value) = set(value, field, { field = it }, BR.loading)
 
     @SuppressLint("InlinedApi")
-    override fun refresh() = viewModelScope.launch {
+    override suspend fun doLoadWork() {
         if (!Utils.showSuperUser()) {
             loading = false
-            return@launch
+            return
         }
         loading = true
         val (policies, diff) = withContext(Dispatchers.IO) {