Add playground files for flow terminal operators

Author: LukasLechnerDev

app/src/main/java/com/lukaslechner/coroutineusecasesonandroid/playground/flow/terminal_operators/1_flows_vs_lists.kt

@@ -1,7 +1,28 @@
 package com.lukaslechner.coroutineusecasesonandroid.playground.flow.terminal_operators
 
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.flow
+
 fun main() {
 
+    val flow = flow {
+        delay(100)
+
+        println("Emitting first value")
+        emit(1)
+
+        delay(100)
+
+        println("Emitting second value")
+        emit(2)
+    }
+
+    val list = buildList {
+        add(1)
+        println("add 1 to list")
 
+        add(2)
+        println("add 2 to list")
+    }
 
 }

app/src/main/java/com/lukaslechner/coroutineusecasesonandroid/playground/flow/terminal_operators/2_collect.kt

@@ -0,0 +1,26 @@
+package com.lukaslechner.coroutineusecasesonandroid.playground.flow.terminal_operators
+
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.flow
+import kotlinx.coroutines.runBlocking
+
+fun main() {
+
+    val flow = flow {
+        delay(100)
+
+        println("Emitting first value")
+        emit(1)
+
+        delay(100)
+
+        println("Emitting second value")
+        emit(2)
+    }
+
+    runBlocking {
+        flow.collect { receivedValue ->
+            println("Received value $receivedValue")
+        }
+    }
+}

app/src/main/java/com/lukaslechner/coroutineusecasesonandroid/playground/flow/terminal_operators/3_first.kt

@@ -0,0 +1,26 @@
+package com.lukaslechner.coroutineusecasesonandroid.playground.flow.terminal_operators
+
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.flow.flow
+import kotlinx.coroutines.runBlocking
+
+fun main() {
+
+    val flow = flow {
+        delay(100)
+
+        println("Emitting first value")
+        emit(1)
+
+        delay(100)
+
+        println("Emitting second value")
+        emit(2)
+    }
+
+    runBlocking {
+        val item = flow.first { it > 1 }
+        println("Received $item")
+    }
+}

app/src/main/java/com/lukaslechner/coroutineusecasesonandroid/playground/flow/terminal_operators/4_last.kt

@@ -0,0 +1,26 @@
+package com.lukaslechner.coroutineusecasesonandroid.playground.flow.terminal_operators
+
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.flow
+import kotlinx.coroutines.flow.last
+import kotlinx.coroutines.runBlocking
+
+fun main() {
+
+    val flow = flow {
+        delay(100)
+
+        println("Emitting first value")
+        emit(1)
+
+        delay(100)
+
+        println("Emitting second value")
+        emit(2)
+    }
+
+    runBlocking {
+        val item = flow.last()
+        println("Received $item")
+    }
+}

app/src/main/java/com/lukaslechner/coroutineusecasesonandroid/playground/flow/terminal_operators/5_single.kt

@@ -0,0 +1,26 @@
+package com.lukaslechner.coroutineusecasesonandroid.playground.flow.terminal_operators
+
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.flow
+import kotlinx.coroutines.flow.single
+import kotlinx.coroutines.runBlocking
+
+fun main() {
+
+    val flow = flow {
+        delay(100)
+
+        println("Emitting first value")
+        emit(1)
+
+        delay(100)
+
+        println("Emitting second value")
+        // emit(2)
+    }
+
+    runBlocking {
+        val item = flow.single()
+        println("Received $item")
+    }
+}

app/src/main/java/com/lukaslechner/coroutineusecasesonandroid/playground/flow/terminal_operators/6_toList_toSet.kt

@@ -0,0 +1,32 @@
+package com.lukaslechner.coroutineusecasesonandroid.playground.flow.terminal_operators
+
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.flow
+import kotlinx.coroutines.flow.toList
+import kotlinx.coroutines.flow.toSet
+import kotlinx.coroutines.runBlocking
+
+fun main() {
+
+    val flow = flow {
+        delay(100)
+
+        println("Emitting first value")
+        emit(1)
+
+        delay(100)
+
+        println("Emitting second value")
+        emit(2)
+    }
+
+    runBlocking {
+        val item = flow.toSet()
+        println("Received $item")
+    }
+
+    runBlocking {
+        val item = flow.toList()
+        println("Received $item")
+    }
+}

app/src/main/java/com/lukaslechner/coroutineusecasesonandroid/playground/flow/terminal_operators/7_fold.kt

@@ -0,0 +1,28 @@
+package com.lukaslechner.coroutineusecasesonandroid.playground.flow.terminal_operators
+
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.flow
+import kotlinx.coroutines.flow.fold
+import kotlinx.coroutines.runBlocking
+
+fun main() {
+
+    val flow = flow {
+        delay(100)
+
+        println("Emitting first value")
+        emit(1)
+
+        delay(100)
+
+        println("Emitting second value")
+        emit(2)
+    }
+
+    runBlocking {
+        val item = flow.fold(5) { accumulator, emittedItem ->
+            accumulator + emittedItem
+        }
+        println("Received $item")
+    }
+}