Miscellaneous improvements

client/src/main/kotlin/io/spine/chords/client/EntityChooser.kt

@@ -70,7 +70,7 @@ public abstract class EntityChooser<
         > : DropdownSelector<I>() {
 
     /**
-     * An enumeration of class's type parameters.
+     * An enumeration of the class's type parameters.
      */
     @Suppress("unused" /* All type parameters are listed for
     completeness despite only a part of them might be used via this enum. */)
@@ -92,10 +92,8 @@ public abstract class EntityChooser<
     private val entityStatesByIds: HashMap<I, E> = hashMapOf()
 
     /**
-     * A function which has to be implemented to provide a value of
-     * type `Class[E]` for the component which is being implemented.
-     *
-     * E.g., if [E] is a `User` class, it would just specify `User::class.java`.
+     * Identifies a type specified for the [E] type parameter by the
+     * implementation of the actual component's instance.
      */
     @OptIn(ExperimentalStdlibApi::class)
     private val entityStateClass: Class<E> get() {
@@ -108,11 +106,13 @@ public abstract class EntityChooser<
             "The V type parameter (entity value type) cannot be a star <*> projection. "
         }
 
-        // We only have the entity state type as an abstract `Type` value at
-        // runtime, so we have no other choice than to explicitly cast it to
-        // Class<E> here (it's safe as long as `TypeParameters` enum is kept
-        // up to date).
-        @Suppress("UNCHECKED_CAST")
+        @Suppress(
+            // We only have the entity state type as an abstract `Type` value at
+            // runtime, so we have no other choice than to explicitly cast it to
+            // Class<E> here (it's safe as long as `TypeParameters` enum is kept
+            // up to date).
+            "UNCHECKED_CAST"
+        )
         return entityStateType.javaType as Class<E>
     }
 

core/build.gradle.kts

@@ -25,6 +25,7 @@
  */
 
 import io.spine.internal.dependency.Kotest
+import io.spine.internal.dependency.Kotlin
 import io.spine.internal.dependency.Material3
 import io.spine.internal.dependency.Voyager
 
@@ -34,7 +35,7 @@ plugins {
 
 dependencies {
     api(Voyager.navigator)
-    implementation(project(":runtime"))
+    implementation(Kotlin.reflect)
     implementation(compose.desktop.currentOs)
     implementation(Material3.Desktop.lib)
     testImplementation(Kotest.runnerJUnit5)

core/src/main/kotlin/io/spine/chords/core/Component.kt

@@ -34,6 +34,8 @@ import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberCoroutineScope
 import io.spine.chords.core.appshell.Props
+import kotlin.reflect.javaType
+import kotlin.reflect.full.allSupertypes
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.isActive
 import kotlinx.coroutines.launch
@@ -180,14 +182,12 @@ import kotlinx.coroutines.launch
  *   perspective this would just be a `someProp` property that can be configured
  *   with any `String` value.
  *
- * Here's an example of creating an input component that allows entering
+ * Here's an example of creating an input component that displays
  * a string value:
  *
  * ```kotlin
  *     public class HelloComponent : Component() {
- *         public companion object : ComponentSetup<HelloComponent>({
- *             HelloComponent()
- *         })
+ *         public companion object : ComponentSetup<HelloComponent>()
  *
  *         public var name: String by mutableStateOf("")
  *
@@ -234,9 +234,8 @@ import kotlinx.coroutines.launch
  *
  * ```kotlin
  *     public class StyledHelloComponent : Component() {
- *         public companion object : ComponentSetup<StyledHelloComponent>({
- *             StyledHelloComponent() // <-- Note child class name. ^^^
- *         })
+ *         public companion object : ComponentSetup<StyledHelloComponent>()
+ *         //                  Note child class name here   ^^^
  *
  *         // Add some more component customization properties...
  *         public var style: TextStyle by mutableStateOf(MaterialTheme.typography.bodyMedium)
@@ -345,7 +344,7 @@ import kotlinx.coroutines.launch
  * Here's an example:
  * ```
  *     public class HelloComponent : Component() {
- *         public companion object : ComponentSetup<HelloComponent>({ HelloComponent() })
+ *         public companion object : ComponentSetup<HelloComponent>()
  *
  *         public lateinit var name: String
  *
@@ -838,7 +837,7 @@ public abstract class Component : DefaultPropsOwnerBase() {
  * @see ComponentSetup
  */
 public abstract class AbstractComponentSetup(
-    protected val createInstance: (() -> Component)? = null
+    protected var createInstance: (() -> Component)? = null
 ) {
 
     /**
@@ -946,14 +945,75 @@ public abstract class AbstractComponentSetup(
  *   should be instantiated and rendered via this companion object).
  *
  * @constructor Creates a companion object for a component of type [C].
- * @param createInstance A lambda that should create a component's instance of
- *   type [C] with the given properties configuration callback.
+ * @param createInstance An optional lambda that should create a component's
+ *   instance of type [C]. In most cases (when a component has the recommended
+ *   no-args constructor), there's no need to specify this parameter.
  * @see AbstractComponentSetup
  */
-public open class ComponentSetup<C: Component>(
-    createInstance: () -> C
+public abstract class ComponentSetup<
+        C : Component // Keep the list of type parameters in sync with the `TypeParameters` enum!
+        >(
+    createInstance: (() -> C)? = null
 ) : AbstractComponentSetup(createInstance) {
 
+    /**
+     * An enumeration of the class's type parameters.
+     */
+    private enum class TypeParameters(val index: Int) {
+
+        /**
+         * The component type parameter (the class's `C` parameter).
+         */
+        COMPONENT_TYPE(0),
+    }
+
+     init {
+         if (this.createInstance == null) {
+             this.createInstance = {
+                 createInstanceByTypeParameter()
+             }
+         }
+     }
+
+    /**
+     * Creates an instance of a component by its type parameter [C], which is
+     * detected automatically from the class instance's implementation.
+     */
+    private fun createInstanceByTypeParameter(): C {
+        val cls = componentClass
+        val defaultConstructor = cls.declaredConstructors.find { it.parameters.isEmpty() }
+        checkNotNull(defaultConstructor) {
+            "A component must have a no-args constructor: $cls"
+        }
+        @Suppress("UNCHECKED_CAST")
+        return defaultConstructor.newInstance() as C
+    }
+
+    /**
+     * Identifies a type specified for the [C] type parameter by the companion
+     * object that implements this class.
+     */
+    @OptIn(ExperimentalStdlibApi::class)
+    private val componentClass: Class<C> get() {
+        val parameterizedEntityChooserType = this::class.allSupertypes.first {
+            it.classifier == ComponentSetup::class
+        }
+        val entityStateType =
+            parameterizedEntityChooserType.arguments[TypeParameters.COMPONENT_TYPE.index].type
+        checkNotNull(entityStateType) {
+            "The C type parameter (component type) cannot be a star <*> projection."
+        }
+
+        @Suppress(
+            // We only have the component type as an abstract `Type` value at
+            // runtime, so we have no other choice than to explicitly cast it to
+            // Class<E> here (it's safe as long as `TypeParameters` enum is kept
+            // up to date).
+            "UNCHECKED_CAST"
+        )
+        return entityStateType.javaType as Class<C>
+    }
+
     /**
      * Declares an instance of component of type [C] with the respective
      * property value specifications.
@@ -965,7 +1025,7 @@ public open class ComponentSetup<C: Component>(
      * Once an instance is created, it is saved using [remember] and is reused
      * for subsequent recompositions.
      *
-     * @param props A lambda that is invoked in context of the component's
+     * @param props A lambda that is invoked in the context of the component's
      *   instance, which should configure its properties in a way that is needed
      *   for this component's instance. It is invoked before each recomposition
      *   of the component.

core/src/main/kotlin/io/spine/chords/core/DropdownSelector.kt

@@ -40,6 +40,8 @@ import androidx.compose.material3.LocalTextStyle
 import androidx.compose.material3.MaterialTheme.colorScheme
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextField
+import androidx.compose.material3.TextFieldColors
+import androidx.compose.material3.TextFieldDefaults
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.SideEffect
 import androidx.compose.runtime.Stable
@@ -125,6 +127,12 @@ public abstract class DropdownSelector<I> : InputComponent<I>() {
      */
     public var modifier: Modifier by mutableStateOf(Modifier)
 
+    /**
+     * A [TextFieldColors] instance, which defines the color scheme for
+     * the selector's field.
+     */
+    public lateinit var fieldColors: TextFieldColors
+
     /**
      * Indicates whether the drop-down menu is expanded or not.
      */
@@ -193,6 +201,9 @@ public abstract class DropdownSelector<I> : InputComponent<I>() {
 
     @Composable
     override fun content() {
+        if (!::fieldColors.isInitialized) {
+            fieldColors = TextFieldDefaults.colors()
+        }
         val fieldText = getFieldText(searchString)
 
         SideEffect {
@@ -236,6 +247,7 @@ public abstract class DropdownSelector<I> : InputComponent<I>() {
                 }
             },
             textStyle = fieldTextStyle,
+            colors = fieldColors,
             modifier = modifier
                 .focusRequester(this@DropdownSelector.focusRequester)
                 .moveFocusOnTab()

core/src/main/kotlin/io/spine/chords/core/InputComponent.kt

@@ -236,15 +236,15 @@ public abstract class InputComponent<V> : FocusableComponent() {
      * implementation to ensure that the value specified in this property is
      * displayed as needed.
      */
-    public open var externalValidationMessage: State<String?>? = null
+    public var externalValidationMessage: State<String?>? = null
 
     /**
      * A callback, which is invoked every time when a component transitions
      * between an empty and dirty state (in any direction). A callback has
      * an argument of `true`, when the new state is dirty, and `false` when it
      * becomes empty.
      */
-    public open var onDirtyStateChange: ((Boolean) -> Unit)? = null
+    public var onDirtyStateChange: ((Boolean) -> Unit)? = null
 
     /**
      * A context that contains any data that affects input components that

core/src/main/kotlin/io/spine/chords/core/InputField.kt

@@ -32,6 +32,8 @@ import androidx.compose.material3.LocalTextStyle
 import androidx.compose.material3.MaterialTheme.colorScheme
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextField
+import androidx.compose.material3.TextFieldColors
+import androidx.compose.material3.TextFieldDefaults
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.MutableState
 import androidx.compose.runtime.Stable
@@ -50,6 +52,7 @@ import androidx.compose.ui.text.input.TextFieldValue
 import androidx.compose.ui.text.input.TransformedText
 import androidx.compose.ui.text.input.VisualTransformation
 import androidx.compose.ui.text.input.VisualTransformation.Companion.None
+import io.spine.chords.core.InputReviser.Companion.maxLength
 import io.spine.chords.core.keyboard.KeyRange.Companion.Digit
 import io.spine.chords.core.keyboard.KeyRange.Companion.Whitespace
 import io.spine.chords.core.keyboard.matches
@@ -306,6 +309,12 @@ public open class InputField<V> : InputComponent<V>() {
      */
     public var textStyle: TextStyle? by mutableStateOf(null)
 
+    /**
+     * A [TextFieldColors] instance, which defines the color scheme for
+     * this field.
+     */
+    public lateinit var colors: TextFieldColors
+
     /**
      * An [InputReviser] that can be specified to modify the user's input before
      * it is applied to the input field.
@@ -367,13 +376,13 @@ public open class InputField<V> : InputComponent<V>() {
     protected open var multiline: Boolean by mutableStateOf(false)
 
     /**
-     * Minimum number of visible lines
+     * Minimum number of visible lines of text
      * (applicable only if [multiline] == `true`).
      */
     protected open var minLines: Int by mutableStateOf(1)
 
     /**
-     * Maximum number of visible lines
+     * Maximum number of visible lines of text
      * (applicable only if [multiline] == `true`).
      */
     protected open var maxLines: Int by mutableStateOf(MAX_VALUE)
@@ -443,6 +452,9 @@ public open class InputField<V> : InputComponent<V>() {
 
     @Composable
     override fun content(): Unit = recompositionWorkaround {
+        if (!::colors.isInitialized) {
+            colors = TextFieldDefaults.colors()
+        }
         val textStyle = textStyle ?: LocalTextStyle.current
         val rawTextContent = getRawTextContent()
 
@@ -477,6 +489,7 @@ public open class InputField<V> : InputComponent<V>() {
             maxLines = if (multiline) maxLines else 1,
             enabled = enabled,
             textStyle = textStyle,
+            colors = colors,
             modifier = modifier(modifier)
                 .focusRequester(focusRequester)
                 .preventWidthAutogrowing()

core/src/main/kotlin/io/spine/chords/core/appshell/MainScreen.kt

@@ -30,7 +30,6 @@ import androidx.compose.material3.Scaffold
 import androidx.compose.runtime.Composable
 import cafe.adriel.voyager.core.screen.Screen
 import cafe.adriel.voyager.navigator.Navigator
-import io.spine.chords.runtime.safeCast
 
 /**
  * The main screen of the application.
@@ -88,5 +87,5 @@ public class MainScreen(
      * Returns the currently selected view.
      */
     internal val currentView: AppView
-        get() = viewNavigator.lastItem.safeCast<AppView>()
+        get() = viewNavigator.lastItem as AppView
 }

core/src/main/kotlin/io/spine/chords/core/layout/Wizard.kt

@@ -207,7 +207,7 @@ public abstract class Wizard : Component() {
                     onFinishClick = {
                         handleFinishClick(currentPage)
                     },
-                    onCancelClick = { onCloseRequest?.invoke() },
+                    onCancelClick = { close() },
                     isOnFirstPage = isOnFirstPage(),
                     isOnLastPage = isOnLastPage(),
                     submitting

core/src/main/kotlin/io/spine/chords/core/primitive/StringField.kt

@@ -36,7 +36,7 @@ import io.spine.chords.core.InputReviser
  * An [InputField] implementation that allows entering `String` values.
  */
 public class StringField : InputField<String>() {
-    public companion object : ComponentSetup<StringField>({ StringField() })
+    public companion object : ComponentSetup<StringField>()
 
     public override var inputReviser: InputReviser?
         get() = super.inputReviser