Do not use viewmodel from simple ui trigger event

Author: yebonkim

app/src/main/java/com/example/wordbook/main/MainFragment.kt

@@ -10,15 +10,12 @@ import android.view.ViewGroup
 import android.widget.Toast
 import androidx.databinding.DataBindingUtil
 import androidx.fragment.app.FragmentManager
-import androidx.lifecycle.lifecycleScope
 import com.example.wordbook.BaseActivity
 import com.example.wordbook.R
 import com.example.wordbook.databinding.FragmentMainBinding
 import com.example.wordbook.study.StudyFragment
 import com.example.wordbook.test.TestFragment
 import com.example.wordbook.vocalist.VocaListBaseFragment
-import com.example.wordbook.vocalist.VocaListFragment
-import kotlinx.coroutines.launch
 
 class MainFragment : Fragment() {
 
@@ -40,37 +37,36 @@ class MainFragment : Fragment() {
 
         binding.viewModel = viewModel
 
-        viewModel.mMoveToStudy.observe(viewLifecycleOwner) {
-            if (it) {
-                lifecycleScope.launch {
-                    if (viewModel.moveToStudyEnabled()) {
-                        addStudyFragment()
-                        viewModel.moveToStudyDone()
-                    } else {
-                        Toast.makeText(context, R.string.error_limit_1_word, Toast.LENGTH_SHORT).show()
-                    }
+        viewModel.mStudyMovingState.observe(viewLifecycleOwner) {
+            when (it) {
+                MovingState.IDLE -> {}
+                MovingState.MOVE -> {
+                    addStudyFragment()
+                    viewModel.setStudyMovingStateIdle()
+                }
+                MovingState.FAIL -> {
+                    Toast.makeText(context, R.string.error_limit_1_word, Toast.LENGTH_SHORT).show()
+                    viewModel.setStudyMovingStateIdle()
                 }
             }
         }
 
-        viewModel.mMoveToTest.observe(viewLifecycleOwner) {
-            if (it) {
-                lifecycleScope.launch {
-                    if (viewModel.moveToTestEnabled()) {
-                        addTestFragment()
-                        viewModel.moveToTestDone()
-                    } else {
-                        Toast.makeText(context, R.string.error_limit_4_word, Toast.LENGTH_SHORT).show()
-                    }
+        viewModel.mTestMovingState.observe(viewLifecycleOwner) {
+            when (it) {
+                MovingState.IDLE -> {}
+                MovingState.MOVE -> {
+                    addTestFragment()
+                    viewModel.setTestMovingStateIdle()
+                }
+                MovingState.FAIL -> {
+                    Toast.makeText(context, R.string.error_limit_4_word, Toast.LENGTH_SHORT).show()
+                    viewModel.setTestMovingStateIdle()
                 }
             }
         }
 
-        viewModel.mMoveToVocaList.observe(viewLifecycleOwner) {
-            if (it) {
-                addVocaListFragment()
-                viewModel.moveToVocaListDone()
-            }
+        binding.register.setOnClickListener {
+            addVocaListFragment()
         }
 
         return binding.root

app/src/main/java/com/example/wordbook/main/MainViewModel.kt

@@ -1,11 +1,16 @@
 package com.example.wordbook.main
 
 import android.app.Application
-import android.util.Log
 import androidx.lifecycle.*
 import com.example.wordbook.database.getDatabase
 import com.example.wordbook.repository.WordRepository
 import kotlinx.coroutines.async
+import kotlinx.coroutines.launch
+
+
+enum class MovingState {
+    IDLE, MOVE, FAIL
+}
 
 class MainViewModel(application: Application): AndroidViewModel(application) {
     companion object {
@@ -14,57 +19,51 @@ class MainViewModel(application: Application): AndroidViewModel(application) {
     }
     private val repository = WordRepository(getDatabase(application))
 
-    private val _mMoveToStudy = MutableLiveData<Boolean>(false)
-    val mMoveToStudy: LiveData<Boolean>
-        get() = _mMoveToStudy
-
-    private val _mMoveToTest = MutableLiveData<Boolean>(false)
-    val mMoveToTest: LiveData<Boolean>
-        get() = _mMoveToTest
+    private val _mStudyMovingState = MutableLiveData<MovingState>(MovingState.IDLE)
+    val mStudyMovingState: LiveData<MovingState>
+        get() = _mStudyMovingState
 
-    private val _mMoveToVocaList= MutableLiveData<Boolean>(false)
-    val mMoveToVocaList: LiveData<Boolean>
-        get() = _mMoveToVocaList
+    private val _mTestMovingState = MutableLiveData<MovingState>(MovingState.IDLE)
+    val mTestMovingState: LiveData<MovingState>
+        get() = _mTestMovingState
 
     fun moveToStudy() {
-        _mMoveToStudy.value = true
+        viewModelScope.launch {
+            if (moveToStudyEnabled()) {
+                _mStudyMovingState.value = MovingState.MOVE
+            } else {
+                _mStudyMovingState.value = MovingState.FAIL
+            }
+        }
     }
 
-    fun moveToStudyDone() {
-        _mMoveToStudy.value = false
+    fun setStudyMovingStateIdle() {
+        _mStudyMovingState.value = MovingState.IDLE
     }
 
     fun moveToTest() {
-        _mMoveToTest.value = true
-    }
-
-    fun moveToTestDone() {
-        _mMoveToTest.value = false
+        viewModelScope.launch {
+            if (moveToTestEnabled()) {
+                _mTestMovingState.value = MovingState.MOVE
+            } else {
+                _mTestMovingState.value = MovingState.FAIL
+            }
+        }
     }
 
-    fun moveToVocaList() {
-        _mMoveToVocaList.value = true
+    fun setTestMovingStateIdle() {
+        _mTestMovingState.value = MovingState.IDLE
     }
 
-    fun moveToVocaListDone() {
-        _mMoveToVocaList.value = false
-    }
-
-    suspend fun moveToStudyEnabled(): Boolean {
+    private suspend fun moveToStudyEnabled(): Boolean {
         return viewModelScope.async {
             repository.getCounts() >= LIMIT_TO_MOVE_STUDY
         }.await()
     }
 
-    suspend fun moveToTestEnabled(): Boolean {
+    private suspend fun moveToTestEnabled(): Boolean {
         return viewModelScope.async {
             repository.getCounts() >= LIMIT_TO_MOVE_TEST
         }.await()
     }
-
-    override fun onCleared() {
-        super.onCleared()
-
-        Log.d("Yebon", "onClear main")
-    }
 }

app/src/main/java/com/example/wordbook/vocalist/VocaListFragment.kt

@@ -38,11 +38,8 @@ class VocaListFragment : Fragment() {
         adapter = VocaListAdapter(::moveToEditVoca)
         binding.list.adapter = adapter
 
-        viewModel.moveToRegisterVoca.observe(viewLifecycleOwner) {
-            if (it) {
-                moveToRegisterVoca()
-                viewModel.moveToRegisterVocaDone()
-            }
+        binding.add.setOnClickListener {
+            moveToRegisterVoca()
         }
 
         viewModel.vocas.observe(viewLifecycleOwner) {

app/src/main/java/com/example/wordbook/vocalist/VocaListViewModel.kt

@@ -12,23 +12,5 @@ import com.example.wordbook.repository.WordRepository
 class VocaListViewModel(application: Application): AndroidViewModel(application) {
     private val repository = WordRepository(getDatabase(application))
 
-    private val _moveToRegisterVoca = MutableLiveData<Boolean>()
-    val moveToRegisterVoca: LiveData<Boolean>
-        get() = _moveToRegisterVoca
-
     val vocas = repository.getWordListByLiveData()
-
-    fun moveToRegisterVoca() {
-        _moveToRegisterVoca.value = true
-    }
-
-    fun moveToRegisterVocaDone() {
-        _moveToRegisterVoca.value = false
-    }
-
-    override fun onCleared() {
-        super.onCleared()
-
-        Log.d("Yebon", "cleared");
-    }
 }

app/src/main/res/layout/fragment_main.xml

@@ -59,7 +59,6 @@
             android:layout_height="wrap_content"
             android:layout_marginTop="20dp"
             android:background="@color/black"
-            android:onClick="@{() -> viewModel.moveToVocaList()}"
             android:text="@string/action_register"
             android:textColor="@color/white"
             app:layout_constraintLeft_toLeftOf="parent"

app/src/main/res/layout/fragment_voca_list.xml

@@ -29,7 +29,6 @@
             android:layout_height="wrap_content"
             android:layout_marginRight="20dp"
             android:layout_marginBottom="20dp"
-            android:onClick="@{() -> viewModel.moveToRegisterVoca()}"
             android:scaleType="centerCrop"
             android:src="@android:drawable/ic_menu_add"
             app:borderWidth="0dp"