ref: jetpack compose working with live data on android sample

Author: android10

android-sample/app/build.gradle.kts

@@ -89,6 +89,9 @@ dependencies {
   implementation(composeBom)
   androidTestImplementation(composeBom)
 
+  // Livedata
+  implementation(libs.androidx.compose.runtime.livedata)
+
   // Material Design 3
   implementation(libs.androidx.compose.material3)
   implementation(libs.androidx.compose.material3.window.size)

android-sample/app/src/main/kotlin/com/fernandocejas/sample/MainActivity.kt

@@ -36,6 +36,7 @@ import androidx.compose.material3.TextField
 import androidx.compose.material3.TopAppBarDefaults
 import androidx.compose.runtime.Composable
 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
@@ -44,6 +45,7 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
+import androidx.core.view.WindowCompat
 
 @OptIn(ExperimentalMaterial3Api::class)
 class MainActivity : AppCompatActivity() {
@@ -53,6 +55,10 @@ class MainActivity : AppCompatActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
+        // Turn off the decor fitting system windows, which allows
+        // us to handle insets, including IME animations.
+        WindowCompat.setDecorFitsSystemWindows(window, false)
+
         setContent {
             MaterialTheme {
                 Surface(
@@ -111,9 +117,24 @@ class MainActivity : AppCompatActivity() {
         textFieldLabel: String = stringResource(id = R.string.txt_encrypt_label_hint)
     ) {
         TextFieldComponent(textFieldLabel)
+//        //////////////////
+        val name = viewModel.encryptedString.observeAsState().value
+//        if (name.isNotEmpty()) {
+            Text(
+                text = "Hello, $name!",
+                modifier = Modifier.padding(bottom = 8.dp),
+                style = MaterialTheme.typography.bodyMedium
+            )
+//        }
+//        //////////////////
         Spacer(modifier = Modifier.height(height = 5.dp))
         Row {
-            ButtonComponent(buttonText)
+            Button(
+                onClick = { viewModel.encryptString("Fernando Cejas") },
+            ) {
+                Text(text = buttonText)
+            }
+//            ButtonComponent(buttonText)
         }
     }
 
@@ -133,7 +154,7 @@ class MainActivity : AppCompatActivity() {
     @Composable
     fun ButtonComponent(buttonText: String) {
         Button(
-            onClick = { },
+            onClick = { viewModel.encryptString("Fernando") },
         ) {
             Text(text = buttonText)
         }

android-sample/app/src/main/kotlin/com/fernandocejas/sample/MainViewModel.kt

@@ -1,20 +1,21 @@
 package com.fernandocejas.sample
 
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
 
 /**
  * Used to communicate between screens.
  */
 class MainViewModel : ViewModel() {
 
-//    private val _drawerShouldBeOpened = MutableStateFlow(false)
-//    val drawerShouldBeOpened = _drawerShouldBeOpened.asStateFlow()
+    private val cryptor = Cryptor()
 
-    fun openDrawer() {
-//        _drawerShouldBeOpened.value = true
-    }
+    private val _encryptedString = MutableLiveData<String>()
+    val encryptedString: LiveData<String> = _encryptedString
 
-    fun resetOpenDrawerAction() {
-//        _drawerShouldBeOpened.value = false
+    fun encryptString(strToEncrypt: String) {
+//        _encryptedString.value = cryptor.encrypt(strToEncrypt)
+        _encryptedString.value = strToEncrypt
     }
 }

android-sample/gradle/libs.versions.toml

@@ -12,6 +12,7 @@ appCompat = "1.6.1"
 materialDesign = "1.1.1"
 composeBom = "2023.05.01"
 activityCompose = "1.7.2"
+liveData = "1.4.3"
 # plugings -------
 androidGradlePlugin = "8.0.2"
 
@@ -24,9 +25,11 @@ kotlinx-coroutines-android = { module = "org.jetbrains.kotlinx:kotlinx-coroutine
 android-core-ktx = { module = "androidx.core:core-ktx", version.ref = "ktx" }
 android-appcompat = { module = "androidx.appcompat:appcompat", version.ref = "appCompat" }
 androidx-compose-bom = { module = "androidx.compose:compose-bom", version.ref = "composeBom" }
+androidx-compose-runtime-livedata = { module = "androidx.compose.runtime:runtime-livedata", version.ref = "liveData" }
 androidx-compose-material3 = { module = "androidx.compose.material3:material3", version.ref = "materialDesign" }
 androidx-compose-material3-window-size = { module = "androidx.compose.material3:material3-window-size-class", version.ref = "materialDesign" }
 androidx-activty-compose = { module = "androidx.activity:activity-compose", version.ref = "activityCompose" }
+
 # tooling --------
 androidx-compose-ui-tooling-preview = { module = "androidx.compose.ui:ui-tooling-preview" }
 androidx-compose-ui-tooling = { module = "androidx.compose.ui:ui-tooling" }