Added Rx module

lazylayout-rx/build.gradle

@@ -0,0 +1,33 @@
+apply plugin: 'com.android.library'
+
+android {
+    compileSdkVersion 28
+
+
+    defaultConfig {
+        minSdkVersion 19
+        targetSdkVersion 28
+        versionCode 1
+        versionName "1.0"
+
+        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
+
+    }
+
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
+        }
+    }
+
+}
+
+dependencies {
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    implementation project(":lazylayout")
+    implementation deps.rxJava
+    implementation deps.rxAndroid
+    implementation deps.androidCore
+    implementation deps.kotlinStdlib
+}

lazylayout-rx/src/main/AndroidManifest.xml

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+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="me.mauricee.lazylayout.rx" />

lazylayout-rx/src/main/java/me/mauricee/lazylayout/rx/RetryObservable.kt

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+@file:JvmName("RxLazyLayout")
+
+package me.mauricee.lazylayout.rx
+
+import androidx.annotation.CheckResult
+import io.reactivex.Observable
+import io.reactivex.Observer
+import io.reactivex.android.MainThreadDisposable
+import me.mauricee.lazylayout.rx.internal.checkMainThread
+import me.mauricee.lazylayout.widget.LazyLayout
+
+@CheckResult
+fun LazyLayout.retries(): Observable<Unit> = RetryObservable(this)
+
+private class RetryObservable(private val lazyLayout: LazyLayout) : Observable<Unit>() {
+
+    override fun subscribeActual(observer: Observer<in Unit>) {
+        if (!checkMainThread(observer)) {
+            return
+        }
+        lazyLayout.retryListener = Listener(lazyLayout, observer).also(observer::onSubscribe)
+    }
+
+    private class Listener(private val lazyLayout: LazyLayout, private val observer: Observer<in Unit>) :
+        MainThreadDisposable(), LazyLayout.RetryListener {
+        override fun onRetry() {
+            if (!isDisposed) {
+                observer.onNext(Unit)
+            }
+        }
+
+        override fun onDispose() {
+            lazyLayout.stateUpdateListener = null
+        }
+
+    }
+}

lazylayout-rx/src/main/java/me/mauricee/lazylayout/rx/StateObservable.kt

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+@file:JvmName("RxLazyLayout")
+
+package me.mauricee.lazylayout.rx
+
+import androidx.annotation.CheckResult
+import io.reactivex.Observable
+import io.reactivex.Observer
+import io.reactivex.android.MainThreadDisposable
+import me.mauricee.lazylayout.rx.internal.checkMainThread
+import me.mauricee.lazylayout.widget.LazyLayout
+
+@CheckResult
+fun LazyLayout.stateChanges(): Observable<Int> = StateObservable(this)
+
+private class StateObservable(private val lazyLayout: LazyLayout) : Observable<Int>() {
+
+    override fun subscribeActual(observer: Observer<in Int>) {
+        if (!checkMainThread(observer)) {
+            return
+        }
+        lazyLayout.stateUpdateListener = Listener(lazyLayout, observer).also(observer::onSubscribe)
+    }
+
+    private class Listener(private val lazyLayout: LazyLayout, private val observer: Observer<in Int>) :
+        MainThreadDisposable(), LazyLayout.StateUpdateListener {
+        override fun onDispose() {
+            lazyLayout.stateUpdateListener = null
+        }
+
+        override fun onStateUpdated(state: Int) {
+            if (!isDisposed) {
+                observer.onNext(state)
+            }
+        }
+
+    }
+}

lazylayout-rx/src/main/java/me/mauricee/lazylayout/rx/internal/MainThread.kt

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+package me.mauricee.lazylayout.rx.internal
+
+import android.os.Looper
+import androidx.annotation.RestrictTo
+import io.reactivex.Observer
+import io.reactivex.disposables.Disposables
+
+@RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
+fun checkMainThread(observer: Observer<*>): Boolean {
+    if (Looper.myLooper() != Looper.getMainLooper()) {
+        observer.onSubscribe(Disposables.empty())
+        observer.onError(IllegalStateException("Expected to be called on the main thread but was " + Thread.currentThread().name))
+        return false
+    }
+    return true
+}

lazylayout-rx/src/main/res/values/strings.xml

@@ -0,0 +1,3 @@
+<resources>
+    <string name="app_name">Rx Lib</string>
+</resources>