Gemini multimodal module refactoring

lethargicpanda · web-flow · commit af472897ad8f · 2025-07-14T18:36:04.000+02:00
diff --git a/ai-catalog/app/src/main/java/com/android/ai/catalog/ui/domain/SampleCatalog.kt b/ai-catalog/app/src/main/java/com/android/ai/catalog/ui/domain/SampleCatalog.kt
@@ -20,7 +20,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.ui.graphics.Color
 import com.android.ai.catalog.R
 import com.android.ai.samples.geminichatbot.GeminiChatbotScreen
-import com.android.ai.samples.geminimultimodal.GeminiMultimodalScreen
+import com.android.ai.samples.geminimultimodal.ui.GeminiMultimodalScreen
 import com.android.ai.samples.geminivideosummary.VideoSummarizationScreen
 import com.android.ai.samples.genai_image_description.GenAIImageDescriptionScreen
 import com.android.ai.samples.genai_summarization.GenAISummarizationScreen
diff --git a/ai-catalog/samples/gemini-multimodal/src/main/java/com/android/ai/samples/geminimultimodal/data/GeminiDataSource.kt b/ai-catalog/samples/gemini-multimodal/src/main/java/com/android/ai/samples/geminimultimodal/data/GeminiDataSource.kt
@@ -13,13 +13,9 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package com.android.ai.samples.geminimultimodal
+package com.android.ai.samples.geminimultimodal.data
 
 import android.graphics.Bitmap
-import androidx.lifecycle.LiveData
-import androidx.lifecycle.MutableLiveData
-import androidx.lifecycle.ViewModel
-import androidx.lifecycle.viewModelScope
 import com.google.firebase.Firebase
 import com.google.firebase.ai.ai
 import com.google.firebase.ai.type.GenerativeBackend
@@ -29,21 +25,13 @@ import com.google.firebase.ai.type.SafetySetting
 import com.google.firebase.ai.type.content
 import com.google.firebase.ai.type.generationConfig
 import javax.inject.Inject
-import kotlinx.coroutines.flow.MutableStateFlow
-import kotlinx.coroutines.flow.StateFlow
-import kotlinx.coroutines.launch
-
-class GeminiMultimodalViewModel @Inject constructor() : ViewModel() {
-
-    private val _textGenerated = MutableStateFlow("")
-    val textGenerated: StateFlow<String> = _textGenerated
-
-    private val _isGenerating = MutableLiveData(false)
-    val isGenerating: LiveData<Boolean> = _isGenerating
+import javax.inject.Singleton
 
+@Singleton
+class GeminiDataSource @Inject constructor() {
     private val generativeModel by lazy {
         Firebase.ai(backend = GenerativeBackend.googleAI()).generativeModel(
-            "gemini-2.0-flash",
+            "gemini-2.5-flash",
             generationConfig = generationConfig {
                 temperature = 0.9f
                 topK = 32
@@ -59,20 +47,12 @@ class GeminiMultimodalViewModel @Inject constructor() : ViewModel() {
         )
     }
 
-    fun generate(bitmap: Bitmap, prompt: String) {
-        _isGenerating.value = true
-
+    suspend fun generateText(bitmap: Bitmap, prompt: String): String {
         val multimodalPrompt = content {
             image(bitmap)
             text(prompt)
         }
-        viewModelScope.launch {
-            val result = generativeModel.generateContent(multimodalPrompt)
-
-            result.text?.let {
-                _textGenerated.value = result.text!!
-            }
-            _isGenerating.postValue(false)
-        }
+        val result = generativeModel.generateContent(multimodalPrompt)
+        return result.text ?: ""
     }
 }
diff --git a/ai-catalog/samples/gemini-multimodal/src/main/java/com/android/ai/samples/geminimultimodal/ui/GeminiMultimodalScreen.kt b/ai-catalog/samples/gemini-multimodal/src/main/java/com/android/ai/samples/geminimultimodal/ui/GeminiMultimodalScreen.kt
@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package com.android.ai.samples.geminimultimodal
+package com.android.ai.samples.geminimultimodal.ui
 
 import android.annotation.SuppressLint
 import android.content.Context
@@ -24,12 +24,14 @@ import androidx.activity.compose.rememberLauncherForActivityResult
 import androidx.activity.result.contract.ActivityResultContracts.TakePicturePreview
 import androidx.compose.foundation.Image
 import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.imePadding
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.rememberScrollState
@@ -40,6 +42,7 @@ import androidx.compose.material.icons.filled.Code
 import androidx.compose.material.icons.filled.SmartToy
 import androidx.compose.material3.Button
 import androidx.compose.material3.Card
+import androidx.compose.material3.CircularProgressIndicator
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.Icon
 import androidx.compose.material3.MaterialTheme
@@ -49,12 +52,11 @@ import androidx.compose.material3.TextField
 import androidx.compose.material3.TopAppBar
 import androidx.compose.material3.TopAppBarDefaults.topAppBarColors
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
-import androidx.compose.runtime.livedata.observeAsState
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.asImageBitmap
 import androidx.compose.ui.layout.ContentScale
@@ -63,16 +65,16 @@ import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import androidx.hilt.navigation.compose.hiltViewModel
+import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import com.android.ai.samples.geminimultimodal.R
 
 @OptIn(ExperimentalMaterial3Api::class)
 @SuppressLint("UnusedMaterial3ScaffoldPaddingParameter")
 @Composable
 fun GeminiMultimodalScreen(viewModel: GeminiMultimodalViewModel = hiltViewModel()) {
     val context = LocalContext.current
     var bitmap by remember { mutableStateOf<Bitmap?>(null) }
-    val textResponse by viewModel.textGenerated.collectAsState()
-    val isGenerating by viewModel.isGenerating.observeAsState(false)
-    var pictureAvailable by remember { mutableStateOf(false) }
+    val uiState by viewModel.uiState.collectAsStateWithLifecycle()
 
     val promptPlaceHolder = stringResource(id = R.string.geminimultimodal_prompt_placeholder)
     var editTextValue by remember {
@@ -83,7 +85,6 @@ fun GeminiMultimodalScreen(viewModel: GeminiMultimodalViewModel = hiltViewModel(
     val cameraLauncher = rememberLauncherForActivityResult(TakePicturePreview()) { result ->
         result?.let {
             bitmap = it
-            pictureAvailable = true
         }
     }
 
@@ -106,6 +107,7 @@ fun GeminiMultimodalScreen(viewModel: GeminiMultimodalViewModel = hiltViewModel(
         Column(
             Modifier
                 .padding(12.dp)
+                .imePadding()
                 .verticalScroll(rememberScrollState())
                 .padding(innerPadding),
         ) {
@@ -116,13 +118,24 @@ fun GeminiMultimodalScreen(viewModel: GeminiMultimodalViewModel = hiltViewModel(
                         height = 450.dp,
                     ),
             ) {
-                bitmap?.let {
+                val currentBitmap = bitmap
+                if (currentBitmap != null) {
                     Image(
-                        bitmap = it.asImageBitmap(),
+                        bitmap = currentBitmap.asImageBitmap(),
                         contentDescription = "Picture",
                         contentScale = ContentScale.Crop,
                         modifier = Modifier.fillMaxSize(),
                     )
+                } else {
+                    Box(
+                        modifier = Modifier.fillMaxSize(),
+                        contentAlignment = Alignment.Center,
+                    ) {
+                        Text(
+                            text = stringResource(id = R.string.geminimultimodal_take_a_picture),
+                            style = MaterialTheme.typography.bodySmall,
+                        )
+                    }
                 }
             }
             Spacer(modifier = Modifier.height(6.dp))
@@ -144,11 +157,12 @@ fun GeminiMultimodalScreen(viewModel: GeminiMultimodalViewModel = hiltViewModel(
             Spacer(modifier = Modifier.height(8.dp))
             Button(
                 onClick = {
-                    if (bitmap != null) {
-                        viewModel.generate(bitmap!!, editTextValue)
+                    val currentBitmap = bitmap
+                    if (currentBitmap != null) {
+                        viewModel.generate(currentBitmap, editTextValue)
                     }
                 },
-                enabled = !isGenerating && pictureAvailable,
+                enabled = uiState !is GeminiMultimodalUiState.Loading && bitmap != null,
             ) {
                 Icon(Icons.Default.SmartToy, contentDescription = "Robot")
                 Text(modifier = Modifier.padding(start = 8.dp), text = "Generate")
@@ -158,14 +172,26 @@ fun GeminiMultimodalScreen(viewModel: GeminiMultimodalViewModel = hiltViewModel(
                     .height(24.dp),
             )
 
-            if (isGenerating) {
-                Text(
-                    text = stringResource(R.string.geminimultimodal_generating),
-                )
-            } else {
-                Text(
-                    text = textResponse,
-                )
+            when (uiState) {
+                is GeminiMultimodalUiState.Initial -> {
+                    Text(
+                        text = stringResource(id = R.string.geminimultimodal_generation_placeholder),
+                        style = MaterialTheme.typography.bodySmall,
+                    )
+                }
+                is GeminiMultimodalUiState.Loading -> {
+                    CircularProgressIndicator()
+                }
+                is GeminiMultimodalUiState.Success -> {
+                    Text(
+                        text = (uiState as GeminiMultimodalUiState.Success).generatedText,
+                    )
+                }
+                is GeminiMultimodalUiState.Error -> {
+                    Text(
+                        text = (uiState as GeminiMultimodalUiState.Error).errorMessage ?: stringResource(R.string.unknown_error),
+                    )
+                }
             }
         }
     }
diff --git a/ai-catalog/samples/gemini-multimodal/src/main/java/com/android/ai/samples/geminimultimodal/ui/GeminiMultimodalUiState.kt b/ai-catalog/samples/gemini-multimodal/src/main/java/com/android/ai/samples/geminimultimodal/ui/GeminiMultimodalUiState.kt
@@ -0,0 +1,23 @@
+/*
+ * Copyright 2025 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.ai.samples.geminimultimodal.ui
+
+sealed interface GeminiMultimodalUiState {
+    data object Initial : GeminiMultimodalUiState
+    data object Loading : GeminiMultimodalUiState
+    data class Success(val generatedText: String) : GeminiMultimodalUiState
+    data class Error(val errorMessage: String?) : GeminiMultimodalUiState
+}
diff --git a/ai-catalog/samples/gemini-multimodal/src/main/java/com/android/ai/samples/geminimultimodal/ui/GeminiMultimodalViewModel.kt b/ai-catalog/samples/gemini-multimodal/src/main/java/com/android/ai/samples/geminimultimodal/ui/GeminiMultimodalViewModel.kt
@@ -0,0 +1,45 @@
+/*
+ * Copyright 2025 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.ai.samples.geminimultimodal.ui
+
+import android.graphics.Bitmap
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import com.android.ai.samples.geminimultimodal.data.GeminiDataSource
+import dagger.hilt.android.lifecycle.HiltViewModel
+import javax.inject.Inject
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.launch
+
+@HiltViewModel
+class GeminiMultimodalViewModel @Inject constructor(private val geminiDataSource: GeminiDataSource) : ViewModel() {
+
+    private val _uiState = MutableStateFlow<GeminiMultimodalUiState>(GeminiMultimodalUiState.Initial)
+    val uiState: StateFlow<GeminiMultimodalUiState> = _uiState
+
+    fun generate(bitmap: Bitmap, prompt: String) {
+        _uiState.value = GeminiMultimodalUiState.Loading
+        viewModelScope.launch {
+            try {
+                val result = geminiDataSource.generateText(bitmap, prompt)
+                _uiState.value = GeminiMultimodalUiState.Success(result)
+            } catch (e: Exception) {
+                _uiState.value = GeminiMultimodalUiState.Error(e.message)
+            }
+        }
+    }
+}
diff --git a/ai-catalog/samples/gemini-multimodal/src/main/res/values/strings.xml b/ai-catalog/samples/gemini-multimodal/src/main/res/values/strings.xml
@@ -2,6 +2,9 @@
 <resources>
     <string name="geminimultimodal_title_bar">Gemini Multimodal</string>
     <string name="geminimultimodal_prompt_placeholder">Describe this picture in a funny way with a lot of emojis</string>
+    <string name="geminimultimodal_generation_placeholder">(Take a picture and enter a prompt to start generating.)</string>
+    <string name="geminimultimodal_take_a_picture">(Take a picture.)</string>"
     <string name="geminimultimodal_generating">Generating&#8230;</string>
     <string name="see_code">See code</string>
+    <string name="unknown_error">Unknown error</string>
 </resources>
