Common flow host and API

Refs: #11

Author: motorro

.idea/deploymentTargetSelector.xml

@@ -0,0 +1,23 @@
+package com.motorro.commonstatemachine.flow
+
+import com.motorro.commonstatemachine.CommonMachineState
+
+/**
+ * Common flow data API
+ */
+interface CommonFlowDataApi<G: Any, U: Any, I, R, F : CommonFlowHost<R>> {
+    /**
+     * Creates flow
+     */
+    fun init(flowHost: F, input: I? = null): CommonMachineState<G, U>
+
+    /**
+     * Returns default UI state
+     */
+    fun getDefaultUiState(): U
+
+    /**
+     * Returns back gesture mapping
+     */
+    fun getBackGesture(): G? = null
+}

.idea/gradle.xml

@@ -0,0 +1,11 @@
+package com.motorro.commonstatemachine.flow
+
+/**
+ * Common flow host
+ */
+interface CommonFlowHost<in R> {
+    /**
+     * Completes common flow
+     */
+    fun onComplete(result: R? = null)
+}

.idea/inspectionProfiles/Project_Default.xml

@@ -66,6 +66,7 @@ dependencies {
     implementation(platform(libs.compose.bom))
 
     implementation(libs.bundles.compose.core)
+    implementation(libs.compose.material.icons)
     implementation(libs.compose.activity)
     implementation(libs.compose.foundation)
     implementation(libs.compose.foundation.layouts)

commonstatemachine/src/commonMain/kotlin/com/motorro/commonstatemachine/flow/CommonFlowApi.kt

@@ -0,0 +1,84 @@
+/*
+ * Copyright 2022 Nikolai Kotchetkov.
+ * 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
+ *    http://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.motorro.statemachine.androidcore.compose
+
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.rounded.Warning
+import androidx.compose.material3.Button
+import androidx.compose.material3.Card
+import androidx.compose.material3.Icon
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.unit.dp
+import com.motorro.statemachine.androidcore.ui.theme.CommonStateMachineTheme
+import java.io.IOException
+
+@Composable
+fun Error(error: Throwable, onDismiss: () -> Unit, modifier: Modifier = Modifier) {
+    Column(
+        modifier = modifier.fillMaxSize(),
+        horizontalAlignment = Alignment.CenterHorizontally,
+        verticalArrangement = Arrangement.Center,
+        content = {
+            Icon(
+                modifier = Modifier.size(255.dp),
+                imageVector = Icons.Rounded.Warning,
+                tint = MaterialTheme.colorScheme.error,
+                contentDescription = "Error",
+            )
+
+            Card(modifier = Modifier
+                .fillMaxWidth()
+                .padding(16.dp)
+                .background(MaterialTheme.colorScheme.errorContainer)
+            ) {
+                Text(
+                    modifier = Modifier
+                        .padding(16.dp)
+                        .align(Alignment.CenterHorizontally),
+                    text = error.message ?: "Unknown error"
+                )
+            }
+            Button(modifier = Modifier
+                .fillMaxWidth()
+                .padding(16.dp),
+                onClick = onDismiss
+            ) {
+                Text("Dismiss")
+            }
+        }
+    )
+}
+
+@Preview
+@Composable
+fun ErrorPreview() {
+    CommonStateMachineTheme {
+        Error(
+            error = IOException("Network error"),
+            onDismiss = {}
+        )
+    }
+}

commonstatemachine/src/commonMain/kotlin/com/motorro/commonstatemachine/flow/CommonFlowHost.kt

@@ -25,9 +25,9 @@ import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 
 @Composable
-fun Loading() {
+fun Loading(modifier: Modifier = Modifier) {
     Column(
-        modifier = Modifier.fillMaxSize(),
+        modifier = modifier.fillMaxSize(),
         horizontalAlignment = Alignment.CenterHorizontally,
         verticalArrangement = Arrangement.Center,
         content = {

examples/androidcore/build.gradle.kts

@@ -0,0 +1 @@
+/build

examples/androidcore/src/main/java/com/motorro/statemachine/androidcore/compose/Error.kt

@@ -0,0 +1,71 @@
+import org.jetbrains.kotlin.gradle.dsl.JvmTarget
+
+/*
+ * Copyright 2026 Nikolai Kotchetkov.
+ * 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
+ *    http://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.
+ */
+
+plugins {
+    alias(libs.plugins.android.lib)
+    alias(libs.plugins.compose)
+}
+
+val androidMinSdkVersion: Int by project.extra
+val androidCompileSdkVersion: Int by project.extra
+
+android {
+    compileSdk = androidCompileSdkVersion
+
+    defaultConfig {
+        minSdk = androidMinSdkVersion
+
+        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
+        consumerProguardFiles("consumer-rules.pro")
+    }
+
+    buildTypes {
+        release {
+            isMinifyEnabled = false
+            proguardFiles(
+                    getDefaultProguardFile("proguard-android-optimize.txt"),
+                    "proguard-rules.pro"
+            )
+        }
+    }
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_17
+        targetCompatibility = JavaVersion.VERSION_17
+        isCoreLibraryDesugaringEnabled = true
+    }
+    kotlin {
+        compilerOptions {
+            jvmTarget.set(JvmTarget.JVM_17)
+        }
+    }
+    buildFeatures {
+        compose = true
+    }
+    namespace = "com.motorro.statemachine.di.api"
+}
+
+dependencies {
+    api(libs.timber)
+
+    api(project(":commonstatemachine"))
+
+    coreLibraryDesugaring(libs.desugaring)
+
+    implementation(libs.kotlin.coroutines.core)
+
+    implementation(platform(libs.compose.bom))
+
+    implementation(libs.bundles.compose.core)
+}