演習7.2

app/todo/src/main/java/jp/co/mixi/androidtraining/todo/ui/TaskItem.kt

@@ -1,28 +1,46 @@
 package jp.co.mixi.androidtraining.todo.ui
 
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Delete
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
 import androidx.compose.material3.ListItem
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.tooling.preview.Preview
+import jp.co.mixi.androidtraining.todo.R
 import jp.co.mixi.androidtraining.todo.data.entity.Task
 
 @Composable
 fun TaskItem(
     task: Task,
+    onDeleteButtonClick: () -> Unit,
     modifier: Modifier = Modifier,
 ) {
     ListItem(
         headlineContent = { Text(text = task.title) },
         modifier = modifier,
+        trailingContent = {
+            IconButton(onClick = onDeleteButtonClick) {
+                Icon(
+                    imageVector = Icons.Default.Delete,
+                    contentDescription = stringResource(id = R.string.delete),
+                )
+            }
+        },
     )
 }
 
 @Preview
 @Composable
 private fun TaskItemPreview() {
     MaterialTheme {
-        TaskItem(task = Task(title = "Task"))
+        TaskItem(
+            task = Task(title = "Task"),
+            onDeleteButtonClick = {},
+        )
     }
 }

app/todo/src/main/java/jp/co/mixi/androidtraining/todo/ui/ToDoScreen.kt

@@ -4,6 +4,8 @@ import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.text.KeyboardActions
+import androidx.compose.foundation.text.KeyboardOptions
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Add
 import androidx.compose.material3.HorizontalDivider
@@ -14,6 +16,7 @@ import androidx.compose.material3.TextField
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.input.ImeAction
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.lifecycle.viewmodel.compose.viewModel
 import jp.co.mixi.androidtraining.todo.R
@@ -29,12 +32,14 @@ fun ToDoScreen(
     Column(modifier = modifier) {
         TaskList(
             tasks = uiState.tasks,
+            onDeleteButtonClick = viewModel::deleteTask,
             modifier = Modifier.weight(1f),
         )
 
         TaskTextField(
             value = uiState.inputText,
             onValueChange = viewModel::setInputText,
+            addButtonEnabled = uiState.addEnabled,
             onAddButtonClick = viewModel::addTask,
             modifier = Modifier.fillMaxWidth(),
         )
@@ -44,11 +49,15 @@ fun ToDoScreen(
 @Composable
 private fun TaskList(
     tasks: List<Task>,
+    onDeleteButtonClick: (Task) -> Unit,
     modifier: Modifier = Modifier,
 ) {
     LazyColumn(modifier = modifier) {
         items(tasks) { task ->
-            TaskItem(task = task)
+            TaskItem(
+                task = task,
+                onDeleteButtonClick = { onDeleteButtonClick(task) },
+            )
             HorizontalDivider()
         }
     }
@@ -58,6 +67,7 @@ private fun TaskList(
 private fun TaskTextField(
     value: String,
     onValueChange: (String) -> Unit,
+    addButtonEnabled: Boolean,
     onAddButtonClick: () -> Unit,
     modifier: Modifier = Modifier,
 ) {
@@ -66,13 +76,22 @@ private fun TaskTextField(
         onValueChange = onValueChange,
         modifier = modifier,
         trailingIcon = {
-            IconButton(onClick = onAddButtonClick) {
+            IconButton(
+                onClick = onAddButtonClick,
+                enabled = addButtonEnabled,
+            ) {
                 Icon(
                     imageVector = Icons.Default.Add,
                     contentDescription = stringResource(id = R.string.add),
                 )
             }
         },
+        keyboardOptions = KeyboardOptions(
+            imeAction = ImeAction.Done,
+        ),
+        keyboardActions = KeyboardActions(
+            onDone = { onAddButtonClick() },
+        ),
     )
 }
 

app/todo/src/main/java/jp/co/mixi/androidtraining/todo/ui/ToDoUiState.kt

@@ -5,4 +5,7 @@ import jp.co.mixi.androidtraining.todo.data.entity.Task
 data class ToDoUiState(
     val tasks: List<Task> = emptyList(),
     val inputText: String = "",
-)
+) {
+    val addEnabled: Boolean
+        get() = inputText.isNotBlank()
+}

app/todo/src/main/java/jp/co/mixi/androidtraining/todo/ui/ToDoViewModel.kt

@@ -20,4 +20,8 @@ class ToDoViewModel : ViewModel() {
             inputText = "",
         )
     }
+
+    fun deleteTask(task: Task) {
+        uiState = uiState.copy(tasks = uiState.tasks - task)
+    }
 }

app/todo/src/main/res/values/strings.xml

@@ -1,4 +1,5 @@
 <resources>
     <string name="app_name">ToDo</string>
     <string name="add">追加</string>
+    <string name="delete">削除</string>
 </resources>