├── .github ├── ISSUE_TEMPLATE └── android_basics_preference_datastore.md ├── .gitignore ├── CONTRIBUTING.md ├── LICENSE ├── README.md ├── app ├── build.gradle ├── proguard-rules.pro └── src │ └── main │ ├── AndroidManifest.xml │ ├── ic_launcher-playstore.png │ ├── java │ └── com │ │ └── example │ │ └── wordsapp │ │ ├── LetterAdapter.kt │ │ ├── LetterListFragment.kt │ │ ├── MainActivity.kt │ │ ├── WordAdapter.kt │ │ └── WordListFragment.kt │ └── res │ ├── drawable │ ├── ic_grid_layout.xml │ ├── ic_launcher_background.xml │ ├── ic_launcher_foreground.xml │ └── ic_linear_layout.xml │ ├── layout │ ├── activity_main.xml │ ├── fragment_letter_list.xml │ ├── fragment_word_list.xml │ └── item_view.xml │ ├── menu │ └── layout_menu.xml │ ├── mipmap-anydpi-v26 │ ├── ic_launcher.xml │ └── ic_launcher_round.xml │ ├── mipmap-hdpi │ ├── ic_launcher.png │ └── ic_launcher_round.png │ ├── mipmap-mdpi │ ├── ic_launcher.png │ └── ic_launcher_round.png │ ├── mipmap-xhdpi │ ├── ic_launcher.png │ └── ic_launcher_round.png │ ├── mipmap-xxhdpi │ ├── ic_launcher.png │ └── ic_launcher_round.png │ ├── mipmap-xxxhdpi │ ├── ic_launcher.png │ └── ic_launcher_round.png │ ├── navigation │ └── nav_graph.xml │ ├── values-night │ └── themes.xml │ └── values │ ├── arrays.xml │ ├── colors.xml │ ├── strings.xml │ ├── styles.xml │ └── themes.xml ├── build.gradle ├── code-of-conduct.md ├── gradle.properties ├── gradle └── wrapper │ ├── gradle-wrapper.jar │ └── gradle-wrapper.properties ├── gradlew ├── gradlew.bat └── settings.gradle /.github/ISSUE_TEMPLATE: -------------------------------------------------------------------------------- 1 | --- 2 | name: Android Basics Unit 3 issue 3 | about: Report problems with the Android Basics Unit 3 codelabs 4 | title: 'Android Basics Unit 3 issue:' 5 | labels: '' 6 | assignees: '' 7 | 8 | --- 9 | 10 | **URL of codelab** 11 | 12 | 13 | **In which task and step of the codelab can this issue be found?** 14 | 15 | 16 | **Describe the problem** 17 | 18 | 19 | 20 | 21 | **Steps to reproduce?** 22 | 1. Go to... 23 | 2. Click on... 24 | 3. See error... 25 | 26 | **Versions** 27 | _Android Studio version:_ 28 | _API version of the emulator:_ 29 | 30 | 31 | **Additional information** 32 | _Include screenshots if they would be useful in clarifying the problem._ 33 | -------------------------------------------------------------------------------- /.github/android_basics_preference_datastore.md: -------------------------------------------------------------------------------- 1 | --- 2 | name: Android Basics: Preference Datastore 3 | about: Report problems with the Android Basics Unit 3 codelabs 4 | title: 'Android Basics: Preference Datastore' 5 | labels: '' 6 | assignees: '' 7 | 8 | --- 9 | 10 | **URL of codelab** 11 | 12 | 13 | **In which task and step of the codelab can this issue be found?** 14 | 15 | 16 | **Describe the problem** 17 | 18 | 19 | 20 | 21 | **Steps to reproduce?** 22 | 1. Go to... 23 | 2. Click on... 24 | 3. See error... 25 | 26 | **Versions** 27 | _Android Studio version:_ 28 | _API version of the emulator:_ 29 | 30 | 31 | **Additional information** 32 | _Include screenshots if they would be useful in clarifying the problem._ 33 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | */.gitignore 2 | .gradle 3 | .DS_Store 4 | 5 | # built application files 6 | *.apk 7 | *.ap_ 8 | 9 | # files for the dex VM 10 | *.dex 11 | 12 | # Java class files 13 | *.class 14 | 15 | # generated files 16 | bin/ 17 | out/ 18 | gen/ 19 | 20 | # Libraries used by the app 21 | /libs 22 | 23 | # Build stuff (auto-generated by android update project ...) 24 | build.xml 25 | ant.properties 26 | local.properties 27 | project.properties 28 | 29 | # Eclipse project files 30 | .classpath 31 | .project 32 | 33 | # idea project files 34 | .idea/ 35 | .idea/.name 36 | *.iml 37 | *.ipr 38 | *.iws 39 | 40 | # Gradle-based build 41 | build/ 42 | -------------------------------------------------------------------------------- /CONTRIBUTING.md: -------------------------------------------------------------------------------- 1 | # How to Contribute 2 | 3 | We'd love to accept your patches and contributions to this project. 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We also recommend that a 186 | file or class name and description of purpose be included on the 187 | same "printed page" as the copyright notice for easier 188 | identification within third-party archives. 189 | 190 | Copyright [yyyy] [name of copyright owner] 191 | 192 | Licensed under the Apache License, Version 2.0 (the "License"); 193 | you may not use this file except in compliance with the License. 194 | You may obtain a copy of the License at 195 | 196 | http://www.apache.org/licenses/LICENSE-2.0 197 | 198 | Unless required by applicable law or agreed to in writing, software 199 | distributed under the License is distributed on an "AS IS" BASIS, 200 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 201 | See the License for the specific language governing permissions and 202 | limitations under the License. -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # Words App 2 | 3 | This folder contains the source code for the Words app codelab. 4 | 5 | 6 | # Introduction 7 | Words app allows you to select a letter and use Intents to navigate to an Activity that 8 | presents a number of words starting with that letter. Each word can be looked up via a web search. 9 | 10 | Words app contains a scrollable list of 26 letters A to Z in a RecyclerView. The orientation 11 | of the RecyclerView can be changed between a vertical list or a grid of items. 12 | 13 | The app demonstrates the use of Intents in two ways: 14 | * to navigate inside an app by specifying an explicit destination, and, 15 | * allowing Android to service the Intent using the apps and resources present on the device. 16 | 17 | # Pre-requisites 18 | * Experience with Kotlin syntax. 19 | * Able to create an Activity. 20 | * Able to create a RecyclerView and supply it with data. 21 | 22 | # Getting Started 23 | 1. Install Android Studio, if you don't already have it. 24 | 2. Download the sample. 25 | 3. Import the sample into Android Studio. 26 | 4. Build and run the sample. 27 | -------------------------------------------------------------------------------- /app/build.gradle: -------------------------------------------------------------------------------- 1 | /* 2 | * Copyright (C) 2020 The Android Open Source Project 3 | * 4 | * Licensed under the Apache License, Version 2.0 (the "License"); 5 | * you may not use this file except in compliance with the License. 6 | * You may obtain a copy of the License at 7 | * 8 | * http://www.apache.org/licenses/LICENSE-2.0 9 | * 10 | * Unless required by applicable law or agreed to in writing, software 11 | * distributed under the License is distributed on an "AS IS" BASIS, 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 | * See the License for the specific language governing permissions and 14 | * limitations under the License. 15 | */ 16 | plugins { 17 | id 'com.android.application' 18 | id 'kotlin-android' 19 | id 'kotlin-kapt' 20 | id 'androidx.navigation.safeargs.kotlin' 21 | } 22 | 23 | android { 24 | compileSdkVersion 33 25 | 26 | defaultConfig { 27 | applicationId "com.example.wordsapp" 28 | minSdkVersion 19 29 | targetSdkVersion 33 30 | versionCode 1 31 | versionName "1.0" 32 | 33 | testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner" 34 | } 35 | 36 | buildTypes { 37 | release { 38 | minifyEnabled false 39 | proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro' 40 | } 41 | } 42 | compileOptions { 43 | sourceCompatibility JavaVersion.VERSION_1_8 44 | targetCompatibility JavaVersion.VERSION_1_8 45 | } 46 | 47 | kotlinOptions { 48 | jvmTarget = '1.8' 49 | } 50 | 51 | buildFeatures { 52 | viewBinding = true 53 | } 54 | } 55 | 56 | dependencies { 57 | implementation "androidx.core:core-ktx:$core_ktx_version" 58 | implementation "androidx.appcompat:appcompat:$appcompat_version" 59 | implementation "com.google.android.material:material:$material_version" 60 | implementation "androidx.constraintlayout:constraintlayout:$constraintlayout_version" 61 | implementation "androidx.navigation:navigation-fragment-ktx:$nav_version" 62 | implementation "androidx.navigation:navigation-ui-ktx:$nav_version" 63 | } -------------------------------------------------------------------------------- /app/proguard-rules.pro: -------------------------------------------------------------------------------- 1 | # Add project specific ProGuard rules here. 2 | # You can control the set of applied configuration files using the 3 | # proguardFiles setting in build.gradle. 4 | # 5 | # For more details, see 6 | # http://developer.android.com/guide/developing/tools/proguard.html 7 | 8 | # If your project uses WebView with JS, uncomment the following 9 | # and specify the fully qualified class name to the JavaScript interface 10 | # class: 11 | #-keepclassmembers class fqcn.of.javascript.interface.for.webview { 12 | # public *; 13 | #} 14 | 15 | # Uncomment this to preserve the line number information for 16 | # debugging stack traces. 17 | #-keepattributes SourceFile,LineNumberTable 18 | 19 | # If you keep the line number information, uncomment this to 20 | # hide the original source file name. 21 | #-renamesourcefileattribute SourceFile -------------------------------------------------------------------------------- /app/src/main/AndroidManifest.xml: -------------------------------------------------------------------------------- 1 | 2 | 17 | 19 | 20 | 27 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | -------------------------------------------------------------------------------- /app/src/main/ic_launcher-playstore.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/google-developer-training/android-basics-kotlin-words-app/4e65a2d83d10ac8f11b40b0253f2f3924095afeb/app/src/main/ic_launcher-playstore.png -------------------------------------------------------------------------------- /app/src/main/java/com/example/wordsapp/LetterAdapter.kt: -------------------------------------------------------------------------------- 1 | /* 2 | * Copyright (C) 2020 The Android Open Source Project 3 | * 4 | * Licensed under the Apache License, Version 2.0 (the "License"); 5 | * you may not use this file except in compliance with the License. 6 | * You may obtain a copy of the License at 7 | * 8 | * http://www.apache.org/licenses/LICENSE-2.0 9 | * 10 | * Unless required by applicable law or agreed to in writing, software 11 | * distributed under the License is distributed on an "AS IS" BASIS, 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 | * See the License for the specific language governing permissions and 14 | * limitations under the License. 15 | */ 16 | package com.example.wordsapp 17 | 18 | import android.os.Build 19 | import android.view.LayoutInflater 20 | import android.view.View 21 | import android.view.ViewGroup 22 | import android.view.accessibility.AccessibilityNodeInfo 23 | import android.widget.Button 24 | import androidx.annotation.RequiresApi 25 | import androidx.navigation.findNavController 26 | import androidx.recyclerview.widget.RecyclerView 27 | 28 | /** 29 | * Adapter for the [RecyclerView] in [MainActivity]. 30 | */ 31 | class LetterAdapter : 32 | RecyclerView.Adapter() { 33 | 34 | // Generates a [CharRange] from 'A' to 'Z' and converts it to a list 35 | private val list = ('A').rangeTo('Z').toList() 36 | 37 | /** 38 | * Provides a reference for the views needed to display items in your list. 39 | */ 40 | class LetterViewHolder(val view: View) : RecyclerView.ViewHolder(view) { 41 | val button = view.findViewById