Add placeholder to SearchScreen text field and focus on when launch screen

feature/sessions/src/commonMain/composeResources/values-ja/strings.xml

@@ -15,6 +15,7 @@
     <string name="workshop">ワークショップ</string>
     <string name="back">戻る</string>
     <string name="search">検索</string>
+    <string name="search_sessions">セッションを検索</string>
     <string name="select_language">言語選択</string>
     <string name="japanese">日本語</string>
     <string name="english">English</string>

feature/sessions/src/commonMain/composeResources/values/strings.xml

@@ -15,6 +15,7 @@
     <string name="workshop">Workshop</string>
     <string name="back">Back</string>
     <string name="search">Search</string>
+    <string name="search_sessions">Search sessions</string>
     <string name="select_language">Select Language</string>
     <string name="japanese">日本語</string>
     <string name="english">English</string>

feature/sessions/src/commonMain/kotlin/io/github/droidkaigi/confsched/sessions/component/SearchTextFieldAppBar.kt

@@ -1,5 +1,6 @@
 package io.github.droidkaigi.confsched.sessions.component
 
+import androidx.compose.foundation.interaction.MutableInteractionSource
 import androidx.compose.foundation.layout.IntrinsicSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
@@ -14,15 +15,27 @@ import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
 import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextFieldDefaults
 import androidx.compose.material3.TopAppBar
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.remember
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.focus.FocusRequester
+import androidx.compose.ui.focus.focusRequester
+import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.SolidColor
 import androidx.compose.ui.platform.LocalFocusManager
 import androidx.compose.ui.platform.LocalSoftwareKeyboardController
 import androidx.compose.ui.platform.testTag
+import androidx.compose.ui.text.font.FontFamily
 import androidx.compose.ui.text.input.ImeAction
+import androidx.compose.ui.text.input.VisualTransformation
+import conference_app_2024.feature.sessions.generated.resources.search_sessions
 import io.github.droidkaigi.confsched.designsystem.theme.KaigiTheme
+import io.github.droidkaigi.confsched.sessions.SessionsRes
+import org.jetbrains.compose.resources.stringResource
 import org.jetbrains.compose.ui.tooling.preview.Preview
 
 const val SearchTextFieldAppBarTextFieldTestTag = "SearchTextFieldAppBarTextField"
@@ -37,7 +50,13 @@ fun SearchTextFieldAppBar(
     modifier: Modifier = Modifier,
 ) {
     val focusManager = LocalFocusManager.current
+    val focusRequester = remember { FocusRequester() }
     val keyboardController = LocalSoftwareKeyboardController.current
+    val interactionSource = remember { MutableInteractionSource() }
+
+    LaunchedEffect(Unit) {
+        focusRequester.requestFocus()
+    }
 
     TopAppBar(
         title = {
@@ -56,7 +75,32 @@ fun SearchTextFieldAppBar(
                         focusManager.clearFocus()
                     },
                 ),
+                decorationBox = { innerTextField ->
+                    TextFieldDefaults.DecorationBox(
+                        value = searchWord,
+                        innerTextField = innerTextField,
+                        enabled = true,
+                        singleLine = true,
+                        visualTransformation = VisualTransformation.None,
+                        interactionSource = interactionSource,
+                        colors = TextFieldDefaults.colors(
+                            focusedContainerColor = Color.Transparent,
+                            unfocusedContainerColor = Color.Transparent,
+                            focusedIndicatorColor = Color.Transparent,
+                            unfocusedIndicatorColor = Color.Transparent,
+                        ),
+                        placeholder = {
+                            Text(
+                                text = stringResource(SessionsRes.string.search_sessions),
+                                style = MaterialTheme.typography.bodyLarge.copy(
+                                    fontFamily = FontFamily.Default,
+                                ),
+                            )
+                        },
+                    )
+                },
                 modifier = Modifier
+                    .focusRequester(focusRequester)
                     .fillMaxWidth()
                     .height(IntrinsicSize.Max)
                     .testTag(SearchTextFieldAppBarTextFieldTestTag),