before presenter refactor

Author: Patrick Jackson

android/src/main/res/layout/fragment_search.xml

@@ -32,9 +32,10 @@
     <androidx.constraintlayout.widget.ConstraintLayout
         android:id="@+id/loading_spinner"
         android:layout_width="match_parent"
-        android:layout_height="match_parent"
+        android:layout_height="0dp"
         android:visibility="gone"
         app:layout_constraintTop_toBottomOf="@+id/txt_search"
+        app:layout_constraintBottom_toBottomOf="parent"
         android:background="@color/white">
 
         <ProgressBar

common/src/commonMain/kotlin/com/willowtreeapps/common/builders.kt

@@ -0,0 +1,70 @@
+package com.willowtreeapps.common
+
+import com.willowtreeapps.common.ui.ViewUpdater
+import org.reduxkotlin.Store
+import org.reduxkotlin.StoreSubscriber
+
+class SelectorSubscriberBuilder<S : Any, View>(val store: Store) {
+    val state: S
+        get() = store.getState() as S
+
+    var withAnyChangeFun: (() -> Unit)? = null
+
+    fun withAnyChange(f: () -> Unit) {
+        withAnyChangeFun = f
+    }
+
+    val selectorList = mutableMapOf<Selector<S, Any>, (Any) -> Unit>()
+    val updaterList = mutableMapOf<Selector<S, Any>, Any>()
+
+    fun withSingleField(selector: (S) -> Any, action: (Any) -> Unit) {
+        val selBuilder = SelectorBuilder<S>()
+        val sel = selBuilder.withSingleField(selector)
+        selectorList[sel] = action
+    }
+
+    fun withSingleField2(selector: (S) -> Any, action: View.()-> Unit) {
+        val selBuilder = SelectorBuilder<S>()
+        val sel = selBuilder.withSingleField(selector)
+        updaterList[sel] = action
+    }
+
+    infix operator fun SelectorSubscriberBuilder<S, View>.plus(selector: (S) -> Any): AbstractSelector<S, Any> {
+        val selBuilder = SelectorBuilder<S>()
+        val sel = selBuilder.withSingleField(selector)
+        return sel
+    }
+
+    infix operator fun AbstractSelector<S, Any>.plus(action: (Any) -> Unit) {
+        selectorList[this] = action
+    }
+
+    infix operator fun AbstractSelector<S, Any>.invoke(action: (Any) -> Unit) {
+        selectorList[this] = action
+    }
+}
+
+/**
+ * Helper function that creates a DSL for subscribing to changes in specific state fields and actions to take.
+ * Inside the lambda there is access to the current state through the var `state`
+ *
+ * ex:
+ *      SelectorSubscriberFn {
+ *          withSingleField({it.foo}, { actionWhenFooChanges() }
+ *
+ *          withAnyChange {
+ *              //called whenever any change happens to state
+ *              view.setMessage(state.barMsg) //state is current state
+ *          }
+ *      }
+ */
+fun <S : Any, View> SelectorSubscriberFn(store: Store, selectorSubscriberBuilderInit: SelectorSubscriberBuilder<S, View>.() -> Unit): StoreSubscriber {
+    val subBuilder = SelectorSubscriberBuilder<S, View>(store)
+    subBuilder.selectorSubscriberBuilderInit()
+    return {
+        subBuilder.selectorList.forEach { entry ->
+            entry.key.onChangeIn(store.getState() as S) { entry.value(store.getState()) }
+        }
+        subBuilder.withAnyChangeFun?.invoke()
+    }
+}