android draw library

app/build.gradle

@@ -53,6 +53,7 @@ dependencies {
     implementation fileTree(include: ['*.jar'], dir: 'libs')
 
     implementation project(':player')
+    implementation project(':draw')
 
     implementation libraries.kotlin
     implementation libraries.coroutines

app/src/main/java/chat/rocket/android/chatroom/ui/ChatRoomFragment.kt

 package chat.rocket.android.chatroom.ui
 
+import android.Manifest
 import android.app.Activity
 import android.content.ClipData
 import android.content.ClipboardManager
 import android.content.Context
 import android.content.Intent
+import android.graphics.Bitmap
+import android.graphics.BitmapFactory
 import android.net.Uri
 import android.os.Bundle
+import android.os.Environment
 import android.os.Handler
 import android.support.annotation.DrawableRes
 import android.support.v4.app.Fragment
@@ -26,6 +30,8 @@ import chat.rocket.android.chatroom.viewmodel.MessageViewModel
 import chat.rocket.android.chatroom.viewmodel.suggestion.ChatRoomSuggestionViewModel
 import chat.rocket.android.chatroom.viewmodel.suggestion.CommandSuggestionViewModel
 import chat.rocket.android.chatroom.viewmodel.suggestion.PeopleSuggestionViewModel
+import chat.rocket.android.draw.DrawingActivity
+import chat.rocket.android.helper.AndroidPermissionsHelper
 import chat.rocket.android.helper.EndlessRecyclerViewScrollListener
 import chat.rocket.android.helper.KeyboardHelper
 import chat.rocket.android.helper.MessageParser
@@ -40,6 +46,10 @@ import kotlinx.android.synthetic.main.fragment_chat_room.*
 import kotlinx.android.synthetic.main.message_attachment_options.*
 import kotlinx.android.synthetic.main.message_composer.*
 import kotlinx.android.synthetic.main.message_list.*
+import timber.log.Timber
+import java.io.File
+import java.io.FileOutputStream
+import java.util.*
 import java.util.concurrent.TimeUnit
 import java.util.concurrent.atomic.AtomicInteger
 import javax.inject.Inject
@@ -71,6 +81,7 @@ private const val BUNDLE_CHAT_ROOM_NAME = "chat_room_name"
 private const val BUNDLE_CHAT_ROOM_TYPE = "chat_room_type"
 private const val BUNDLE_IS_CHAT_ROOM_READ_ONLY = "is_chat_room_read_only"
 private const val REQUEST_CODE_FOR_PERFORM_SAF = 42
+private const val REQUEST_CODE_FOR_DRAW = 101
 private const val BUNDLE_CHAT_ROOM_LAST_SEEN = "chat_room_last_seen"
 private const val BUNDLE_CHAT_ROOM_IS_SUBSCRIBED = "chat_room_is_subscribed"
 private const val BUNDLE_CHAT_ROOM_IS_OWNER = "chat_room_is_owner"
@@ -180,13 +191,34 @@ class ChatRoomFragment : Fragment(), ChatRoomView, EmojiKeyboardListener, EmojiR
     }
 
     override fun onActivityResult(requestCode: Int, resultCode: Int, resultData: Intent?) {
-        if (requestCode == REQUEST_CODE_FOR_PERFORM_SAF && resultCode == Activity.RESULT_OK) {
-            if (resultData != null) {
-                uploadFile(resultData.data)
+        if (resultData != null && resultCode == Activity.RESULT_OK) {
+            when(requestCode){
+                REQUEST_CODE_FOR_PERFORM_SAF -> {
+                    uploadFile(resultData.data)
+                }
+                REQUEST_CODE_FOR_DRAW -> {
+                    val result= resultData.getByteArrayExtra("bitmap")
+                    val bitmap = BitmapFactory.decodeByteArray(result, 0, result.size)
+                    val uri = saveImage(bitmap)
+                    uploadFile(uri)
+                }
             }
         }
     }
 
+    private fun saveImage(bitmap: Bitmap): Uri {
+        val imageDir = "${Environment.DIRECTORY_PICTURES}/Rocket.Chat Images/"
+        val path = Environment.getExternalStoragePublicDirectory(imageDir)
+        val file = File(path, UUID.randomUUID().toString()+".png")
+        path.mkdirs()
+        file.createNewFile()
+        val outputStream = FileOutputStream(file)
+        bitmap.compress(Bitmap.CompressFormat.PNG,100,outputStream)
+        outputStream.flush()
+        outputStream.close()
+        return Uri.fromFile(file)
+    }
+
     override fun onCreateOptionsMenu(menu: Menu, inflater: MenuInflater) {
         super.onCreateOptionsMenu(menu, inflater)
         inflater.inflate(R.menu.chatroom_actions, menu)
@@ -675,6 +707,18 @@ class ChatRoomFragment : Fragment(), ChatRoomView, EmojiKeyboardListener, EmojiR
             button_add_reaction.setOnClickListener { view ->
                 openEmojiKeyboardPopup()
             }
+
+            button_drawing.setOnClickListener {
+                if (!canWriteToExternalStorage()) {
+                    checkWritingPermission()
+                }else{
+                    val intent = Intent(activity,DrawingActivity::class.java)
+                    startActivityForResult(intent, REQUEST_CODE_FOR_DRAW)
+                }
+                handler.postDelayed({
+                    hideAttachmentOptions()
+                }, 400)
+            }
         }
     }
 
@@ -793,4 +837,16 @@ class ChatRoomFragment : Fragment(), ChatRoomView, EmojiKeyboardListener, EmojiR
     private fun setupToolbar(toolbarTitle: String) {
         (activity as ChatRoomActivity).setupToolbarTitle(toolbarTitle)
     }
+
+    private fun canWriteToExternalStorage(): Boolean {
+        return context?.let { AndroidPermissionsHelper.checkPermission(it, Manifest.permission.WRITE_EXTERNAL_STORAGE) }!!
+    }
+
+    private fun checkWritingPermission() {
+        activity?.let {
+            AndroidPermissionsHelper.requestPermission(it,
+                    Manifest.permission.WRITE_EXTERNAL_STORAGE,
+                    AndroidPermissionsHelper.WRITE_EXTERNAL_STORAGE_CODE)
+        }
+    }
 }
\ No newline at end of file

app/src/main/res/drawable/ic_gesture_black_24dp.xml

+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+        android:width="24dp"
+        android:height="24dp"
+        android:viewportWidth="24.0"
+        android:viewportHeight="24.0">
+    <path
+        android:fillColor="#FF1D74F5"
+        android:pathData="M4.59,6.89c0.7,-0.71 1.4,-1.35 1.71,-1.22 0.5,0.2 0,1.03 -0.3,1.52 -0.25,0.42 -2.86,3.89 -2.86,6.31 0,1.28 0.48,2.34 1.34,2.98 0.75,0.56 1.74,0.73 2.64,0.46 1.07,-0.31 1.95,-1.4 3.06,-2.77 1.21,-1.49 2.83,-3.44 4.08,-3.44 1.63,0 1.65,1.01 1.76,1.79 -3.78,0.64 -5.38,3.67 -5.38,5.37 0,1.7 1.44,3.09 3.21,3.09 1.63,0 4.29,-1.33 4.69,-6.1L21,14.88v-2.5h-2.47c-0.15,-1.65 -1.09,-4.2 -4.03,-4.2 -2.25,0 -4.18,1.91 -4.94,2.84 -0.58,0.73 -2.06,2.48 -2.29,2.72 -0.25,0.3 -0.68,0.84 -1.11,0.84 -0.45,0 -0.72,-0.83 -0.36,-1.92 0.35,-1.09 1.4,-2.86 1.85,-3.52 0.78,-1.14 1.3,-1.92 1.3,-3.28C8.95,3.69 7.31,3 6.44,3 5.12,3 3.97,4 3.72,4.25c-0.36,0.36 -0.66,0.66 -0.88,0.93l1.75,1.71zM13.88,18.55c-0.31,0 -0.74,-0.26 -0.74,-0.72 0,-0.6 0.73,-2.2 2.87,-2.76 -0.3,2.69 -1.43,3.48 -2.13,3.48z"/>
+</vector>

app/src/main/res/layout/message_attachment_options.xml

@@ -15,4 +15,14 @@
         android:gravity="start|center"
         android:text="@string/action_files" />
 
+    <Button
+        android:id="@+id/button_drawing"
+        style="?android:attr/borderlessButtonStyle"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:drawablePadding="20dp"
+        android:drawableStart="@drawable/ic_gesture_black_24dp"
+        android:gravity="start|center"
+        android:text="Drawing" />
+
 </LinearLayout>
\ No newline at end of file

app/src/main/res/values-es/strings.xml

@@ -34,6 +34,7 @@
     <string name="action_away">Ausente</string>
     <string name="action_busy">Ocupado</string>
     <string name="action_invisible">Invisible</string>
+    <string name="action_drawing">Dibujo</string>
 
     <!-- Settings List -->
     <string-array name="settings_actions">

app/src/main/res/values-fr/strings.xml

@@ -34,6 +34,7 @@
     <string name="action_away">Loin</string>
     <string name="action_busy">Occupé</string>
     <string name="action_invisible">Invisible</string>
+    <string name="action_drawing">Dessin</string>
 
     <!-- Settings List -->
     <string-array name="settings_actions">

app/src/main/res/values-hi-rIN/strings.xml

@@ -35,6 +35,7 @@
     <string name="action_away">दूर</string>
     <string name="action_busy">व्यस्त</string>
     <string name="action_invisible">अदृश्य</string>
+    <string name="action_drawing">चित्रकारी</string>
 
     <!-- Settings List -->
     <string-array name="settings_actions">

app/src/main/res/values-pt-rBR/strings.xml

@@ -34,6 +34,7 @@
     <string name="action_away">Ausente</string>
     <string name="action_busy">Ocupado</string>
     <string name="action_invisible">Invisível</string>
+    <string name="action_drawing">Desenhando</string>
 
     <!-- Settings List -->
     <string-array name="settings_actions">

app/src/main/res/values-uk-rUA/strings.xml

@@ -36,6 +36,7 @@
     <string name="action_away">Away</string>
     <string name="action_busy">Busy</string>
     <string name="action_invisible">Invisible</string>
+    <string name="action_drawing">Drawing</string>
 
     <!-- Settings List -->
     <string-array name="settings_actions">

app/src/main/res/values/strings.xml

@@ -35,6 +35,7 @@
     <string name="action_away">Away</string>
     <string name="action_busy">Busy</string>
     <string name="action_invisible">Invisible</string>
+    <string name="action_drawing">Drawing</string>
 
     <!-- Settings List -->
     <string-array name="settings_actions">

build.gradle

 // Top-level build file where you can add configuration options common to all sub-projects/modules.
-buildscript {
+buildscript { 
+    ext.kotlin_version = '1.2.31'
+
     apply from: rootProject.file('dependencies.gradle')
 
     repositories {
@@ -19,7 +21,7 @@ buildscript {
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
-    }
+    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version" }
 }
 
 allprojects {
@@ -35,4 +37,4 @@ allprojects {
 
 task clean(type: Delete) {
     delete rootProject.buildDir
-}
+}
\ No newline at end of file

draw/.gitignore

+/build

draw/build.gradle

+apply plugin: 'com.android.library'
+
+android {
+    compileSdkVersion 27
+
+
+
+    defaultConfig {
+        minSdkVersion 21
+        targetSdkVersion 27
+        versionCode 1
+        versionName "1.0"
+
+        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+
+    }
+
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+        }
+    }
+
+}
+
+dependencies {
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+
+    implementation libraries.appCompat
+    implementation libraries.constraintLayout
+    implementation libraries.kotlin
+    implementation libraries.androidKtx
+
+
+    testImplementation 'junit:junit:4.12'
+    androidTestImplementation 'com.android.support.test:runner:1.0.2'
+    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
+}
+
+apply plugin: 'kotlin-android'
+apply plugin: 'kotlin-android-extensions'

draw/proguard-rules.pro

+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile

draw/src/androidTest/java/chat/rocket/android/draw/ExampleInstrumentedTest.java

+package chat.rocket.android.draw;
+
+import android.content.Context;
+import android.support.test.InstrumentationRegistry;
+import android.support.test.runner.AndroidJUnit4;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import static org.junit.Assert.*;
+
+/**
+ * Instrumented test, which will execute on an Android device.
+ *
+ * @see <a href="http://d.android.com/tools/testing">Testing documentation</a>
+ */
+@RunWith(AndroidJUnit4.class)
+public class ExampleInstrumentedTest {
+    @Test
+    public void useAppContext() {
+        // Context of the app under test.
+        Context appContext = InstrumentationRegistry.getTargetContext();
+
+        assertEquals("chat.rocket.android.draw.test", appContext.getPackageName());
+    }
+}

draw/src/main/AndroidManifest.xml

+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="chat.rocket.android.draw">
+
+    <application>
+        <activity
+            android:name=".DrawingActivity"
+            android:theme="@style/Theme.AppCompat.Light.NoActionBar" />
+    </application>
+
+</manifest>
\ No newline at end of file

draw/src/main/java/chat/rocket/android/draw/DrawingActivity.kt

+package chat.rocket.android.draw
+
+import android.content.res.Resources
+import android.support.v7.app.AppCompatActivity
+import android.os.Bundle
+import android.support.v4.content.res.ResourcesCompat
+import android.view.View
+import android.widget.SeekBar
+import androidx.core.view.isVisible
+import kotlinx.android.synthetic.main.activity_drawing.*
+import kotlinx.android.synthetic.main.color_palette_view.*
+import android.content.Intent
+import android.graphics.Bitmap
+import android.app.Activity
+import java.io.ByteArrayOutputStream
+
+
+class DrawingActivity : AppCompatActivity() {
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_drawing)
+
+        image_close_drawing.setOnClickListener {
+            finish()
+        }
+        image_send_drawing.setOnClickListener {
+            val bStream = ByteArrayOutputStream()
+            val bitmap = custom_draw_view.getBitmap()
+            bitmap.compress(Bitmap.CompressFormat.PNG, 100, bStream)
+            val byteArray = bStream.toByteArray()
+            val returnIntent = Intent()
+            returnIntent.putExtra("bitmap", byteArray)
+            setResult(Activity.RESULT_OK,returnIntent)
+            finish()
+        }
+
+        setUpDrawTools()
+
+        colorSelector()
+
+        setPaintAlpha()
+
+        setPaintWidth()
+    }
+
+    private fun setUpDrawTools() {
+        image_draw_eraser.setOnClickListener {
+            custom_draw_view.clearCanvas()
+            toggleDrawTools(draw_tools,false)
+        }
+        image_draw_width.setOnClickListener {
+            if (draw_tools.translationY == (56).toPx){
+                toggleDrawTools(draw_tools,true)
+            }else if (draw_tools.translationY == (0).toPx && seekBar_width.isVisible){
+                toggleDrawTools(draw_tools,false)
+            }
+            seekBar_width.isVisible = true
+            seekBar_opacity.isVisible = false
+            draw_color_palette.isVisible = false
+        }
+        image_draw_opacity.setOnClickListener {
+            if (draw_tools.translationY == (56).toPx){
+                toggleDrawTools(draw_tools,true)
+            }else if (draw_tools.translationY == (0).toPx && seekBar_opacity.isVisible){
+                toggleDrawTools(draw_tools,false)
+            }
+            seekBar_width.isVisible = false
+            seekBar_opacity.isVisible = true
+            draw_color_palette.isVisible = false
+        }
+        image_draw_color.setOnClickListener {
+            if (draw_tools.translationY == (56).toPx){
+                toggleDrawTools(draw_tools,true)
+            }else if (draw_tools.translationY == (0).toPx && draw_color_palette.isVisible){
+                toggleDrawTools(draw_tools,false)
+            }
+            seekBar_width.isVisible = false
+            seekBar_opacity.isVisible = false
+            draw_color_palette.isVisible = true
+        }
+        image_draw_undo.setOnClickListener {
+            custom_draw_view.undo()
+            toggleDrawTools(draw_tools,false)
+        }
+        image_draw_redo.setOnClickListener {
+            custom_draw_view.redo()
+            toggleDrawTools(draw_tools,false)
+        }
+    }
+
+    private fun toggleDrawTools(view: View, showView: Boolean = true) {
+        if (showView){
+            view.animate().translationY((0).toPx)
+        }else{
+            view.animate().translationY((56).toPx)
+        }
+    }
+
+    private fun colorSelector() {
+        image_color_black.setOnClickListener {
+            custom_draw_view.setColor(ResourcesCompat.getColor(resources, R.color.color_black,null))
+            scaleColorView(image_color_black)
+        }
+        image_color_red.setOnClickListener {
+            custom_draw_view.setColor(ResourcesCompat.getColor(resources, R.color.color_red,null))
+            scaleColorView(image_color_red)
+        }
+        image_color_yellow.setOnClickListener {
+            custom_draw_view.setColor(ResourcesCompat.getColor(resources, R.color.color_yellow,null))
+            scaleColorView(image_color_yellow)
+        }
+        image_color_green.setOnClickListener {
+            custom_draw_view.setColor(ResourcesCompat.getColor(resources, R.color.color_green,null))
+            scaleColorView(image_color_green)
+        }
+        image_color_blue.setOnClickListener {
+            custom_draw_view.setColor(ResourcesCompat.getColor(resources, R.color.color_blue,null))
+            scaleColorView(image_color_blue)
+        }
+        image_color_pink.setOnClickListener {
+            custom_draw_view.setColor(ResourcesCompat.getColor(resources, R.color.color_pink,null))
+            scaleColorView(image_color_pink)
+        }
+        image_color_brown.setOnClickListener {
+            custom_draw_view.setColor(ResourcesCompat.getColor(resources, R.color.color_brown,null))
+            scaleColorView(image_color_brown)
+        }
+    }
+
+    private fun scaleColorView(view: View) {
+        //reset scale of all views
+        image_color_black.scaleX = 1f
+        image_color_black.scaleY = 1f
+
+        image_color_red.scaleX = 1f
+        image_color_red.scaleY = 1f
+
+        image_color_yellow.scaleX = 1f
+        image_color_yellow.scaleY = 1f
+
+        image_color_green.scaleX = 1f
+        image_color_green.scaleY = 1f
+
+        image_color_blue.scaleX = 1f
+        image_color_blue.scaleY = 1f
+
+        image_color_pink.scaleX = 1f
+        image_color_pink.scaleY = 1f
+
+        image_color_brown.scaleX = 1f
+        image_color_brown.scaleY = 1f
+
+        //set scale of selected view
+        view.scaleX = 1.5f
+        view.scaleY = 1.5f
+    }
+
+    private fun setPaintWidth() {
+        seekBar_width.setOnSeekBarChangeListener(object: SeekBar.OnSeekBarChangeListener{
+            override fun onProgressChanged(seekBar: SeekBar?, progress: Int, fromUser: Boolean) {
+                custom_draw_view.setStrokeWidth(progress.toFloat())
+            }
+
+            override fun onStartTrackingTouch(seekBar: SeekBar?) {}
+
+            override fun onStopTrackingTouch(seekBar: SeekBar?) {}
+        })
+    }
+
+    private fun setPaintAlpha() {
+        seekBar_opacity.setOnSeekBarChangeListener(object: SeekBar.OnSeekBarChangeListener{
+            override fun onProgressChanged(seekBar: SeekBar?, progress: Int, fromUser: Boolean) {
+                custom_draw_view.setAlpha(progress)
+            }
+
+            override fun onStartTrackingTouch(seekBar: SeekBar?) {}
+
+            override fun onStopTrackingTouch(seekBar: SeekBar?) {}
+        })
+    }
+
+    private val Int.toPx: Float
+        get() = (this * Resources.getSystem().displayMetrics.density)
+}

draw/src/main/java/chat/rocket/android/draw/widget/Action.kt

+package chat.rocket.android.draw.widget
+
+import android.graphics.Path
+import java.io.Serializable
+import java.io.Writer
+
+interface Action : Serializable {
+    fun perform(path: Path)
+
+    fun perform(writer: Writer)
+}

draw/src/main/java/chat/rocket/android/draw/widget/CustomDrawView.kt

+package chat.rocket.android.draw.widget
+
+import android.content.Context
+import android.graphics.*
+import android.util.AttributeSet
+import android.view.MotionEvent
+import android.view.View
+import java.util.*
+import android.support.v4.graphics.ColorUtils
+import android.support.annotation.ColorInt
+
+class CustomDrawView(context: Context, attrs: AttributeSet) : View(context, attrs) {
+    var mPaths = LinkedHashMap<MyPath, PaintOptions>()
+
+    private var mLastPaths = LinkedHashMap<MyPath, PaintOptions>()
+    private var mUndonePaths = LinkedHashMap<MyPath, PaintOptions>()
+
+    private var mPaint = Paint()
+    private var mPath = MyPath()
+    private var mPaintOptions = PaintOptions()
+
+    private var mCurX = 0f
+    private var mCurY = 0f
+    private var mStartX = 0f
+    private var mStartY = 0f
+    private var mIsSaving = false
+    private var mIsStrokeWidthBarEnabled = false
+
+    init {
+        mPaint.apply {
+            color = mPaintOptions.color
+            style = Paint.Style.STROKE
+            strokeJoin = Paint.Join.ROUND
+            strokeCap = Paint.Cap.ROUND
+            strokeWidth = mPaintOptions.strokeWidth
+            isAntiAlias = true
+        }
+    }
+
+    fun undo() {
+        if (mPaths.isEmpty() && mLastPaths.isNotEmpty()) {
+            mPaths = mLastPaths.clone() as LinkedHashMap<MyPath, PaintOptions>
+            mLastPaths.clear()
+            invalidate()
+            return
+        }
+        if (mPaths.isEmpty()) {
+            return
+        }
+        val lastPath = mPaths.values.lastOrNull()
+        val lastKey = mPaths.keys.lastOrNull()
+
+        mPaths.remove(lastKey)
+        if (lastPath != null && lastKey != null) {
+            mUndonePaths[lastKey] = lastPath
+        }
+        invalidate()
+    }
+
+    fun redo() {
+        if (mUndonePaths.keys.isEmpty()) {
+            return
+        }
+
+        val lastKey = mUndonePaths.keys.last()
+        addPath(lastKey, mUndonePaths.values.last())
+        mUndonePaths.remove(lastKey)
+        invalidate()
+    }
+
+    fun setColor(newColor: Int) {
+        @ColorInt
+        val alphaColor = ColorUtils.setAlphaComponent(newColor, mPaintOptions.alpha)
+        mPaintOptions.color = alphaColor
+        if (mIsStrokeWidthBarEnabled) {
+            invalidate()
+        }
+    }
+
+    fun setAlpha(newAlpha: Int) {
+        val alpha = (newAlpha*255)/100
+        mPaintOptions.alpha = alpha
+        setColor(mPaintOptions.color)
+    }
+
+    fun setStrokeWidth(newStrokeWidth: Float) {
+        mPaintOptions.strokeWidth = newStrokeWidth
+        if (mIsStrokeWidthBarEnabled) {
+            invalidate()
+        }
+    }
+
+    fun getBitmap(): Bitmap {
+        val bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888)
+        val canvas = Canvas(bitmap)
+        canvas.drawColor(Color.WHITE)
+        mIsSaving = true
+        draw(canvas)
+        mIsSaving = false
+        return bitmap
+    }
+
+    fun addPath(path: MyPath, options: PaintOptions) {
+        mPaths[path] = options
+    }
+
+    override fun onDraw(canvas: Canvas) {
+        super.onDraw(canvas)
+
+        for ((key, value) in mPaths) {
+            changePaint(value)
+            canvas.drawPath(key, mPaint)
+        }
+
+        changePaint(mPaintOptions)
+        canvas.drawPath(mPath, mPaint)
+    }
+
+    private fun changePaint(paintOptions: PaintOptions) {
+        mPaint.color = paintOptions.color
+        mPaint.strokeWidth = paintOptions.strokeWidth
+    }
+
+    fun clearCanvas() {
+        mLastPaths = mPaths.clone() as LinkedHashMap<MyPath, PaintOptions>
+        mPath.reset()
+        mPaths.clear()
+        invalidate()
+    }
+
+    private fun actionDown(x: Float, y: Float) {
+        mPath.reset()
+        mPath.moveTo(x, y)
+        mCurX = x
+        mCurY = y
+    }
+
+    private fun actionMove(x: Float, y: Float) {
+        mPath.quadTo(mCurX, mCurY, (x + mCurX) / 2, (y + mCurY) / 2)
+        mCurX = x
+        mCurY = y
+    }
+
+    private fun actionUp() {
+        mPath.lineTo(mCurX, mCurY)
+
+        // draw a dot on click
+        if (mStartX == mCurX && mStartY == mCurY) {
+            mPath.lineTo(mCurX, mCurY + 2)
+            mPath.lineTo(mCurX + 1, mCurY + 2)
+            mPath.lineTo(mCurX + 1, mCurY)
+        }
+
+        mPaths.put(mPath, mPaintOptions)
+        mPath = MyPath()
+        mPaintOptions = PaintOptions(mPaintOptions.color, mPaintOptions.strokeWidth, mPaintOptions.alpha)
+    }
+
+    override fun onTouchEvent(event: MotionEvent): Boolean {
+        val x = event.x
+        val y = event.y
+
+        when (event.action) {
+            MotionEvent.ACTION_DOWN -> {
+                mStartX = x
+                mStartY = y
+                actionDown(x, y)
+                mUndonePaths.clear()
+            }
+            MotionEvent.ACTION_MOVE -> actionMove(x, y)
+            MotionEvent.ACTION_UP -> actionUp()
+        }
+
+        invalidate()
+        return true
+    }
+}
\ No newline at end of file

draw/src/main/java/chat/rocket/android/draw/widget/Line.kt

+package chat.rocket.android.draw.widget
+
+import android.graphics.Path
+import java.io.Writer
+import java.security.InvalidParameterException
+
+class Line(val x: Float, val y: Float) : Action {
+
+    override fun perform(path: Path) {
+        path.lineTo(x, y)
+    }
+
+    override fun perform(writer: Writer) {
+        writer.write("L$x,$y")
+    }
+}
\ No newline at end of file

draw/src/main/java/chat/rocket/android/draw/widget/Move.kt

+package chat.rocket.android.draw.widget
+
+import android.graphics.Path
+import java.io.Writer
+import java.security.InvalidParameterException
+
+class Move(val x: Float, val y: Float) : Action {
+
+    override fun perform(path: Path) {
+        path.moveTo(x, y)
+    }
+
+    override fun perform(writer: Writer) {
+        writer.write("M$x,$y")
+    }
+}
\ No newline at end of file

draw/src/main/java/chat/rocket/android/draw/widget/MyPath.kt

+package chat.rocket.android.draw.widget
+
+import android.graphics.Path
+import java.io.ObjectInputStream
+import java.io.Serializable
+import java.util.*
+
+class MyPath : Path(), Serializable {
+    val actions = LinkedList<Action>()
+
+    private fun readObject(inputStream: ObjectInputStream) {
+        inputStream.defaultReadObject()
+
+        val copiedActions = actions.map { it }
+        copiedActions.forEach {
+            it.perform(this)
+        }
+    }
+
+    override fun reset() {
+        actions.clear()
+        super.reset()
+    }
+
+    override fun moveTo(x: Float, y: Float) {
+        actions.add(Move(x, y))
+        super.moveTo(x, y)
+    }
+
+    override fun lineTo(x: Float, y: Float) {
+        actions.add(Line(x, y))
+        super.lineTo(x, y)
+    }
+
+    override fun quadTo(x1: Float, y1: Float, x2: Float, y2: Float) {
+        actions.add(Quad(x1, y1, x2, y2))
+        super.quadTo(x1, y1, x2, y2)
+    }
+}
\ No newline at end of file

draw/src/main/java/chat/rocket/android/draw/widget/PaintOptions.kt

+package chat.rocket.android.draw.widget
+
+import android.graphics.Color
+
+data class PaintOptions(var color: Int = Color.BLACK, var strokeWidth: Float = 8f, var alpha: Int = 255)

draw/src/main/java/chat/rocket/android/draw/widget/Quad.kt

+package chat.rocket.android.draw.widget
+
+import android.graphics.Path
+import java.io.Writer
+
+class Quad(private val x1: Float, private val y1: Float, private val x2: Float, private val y2: Float) : Action {
+
+    override fun perform(path: Path) {
+        path.quadTo(x1, y1, x2, y2)
+    }
+
+    override fun perform(writer: Writer) {
+        writer.write("Q$x1,$y1 $x2,$y2")
+    }
+}
\ No newline at end of file

draw/src/main/res/drawable/circle_black.xml

+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="oval">
+
+    <solid android:color="@color/color_black" />
+    <corners android:radius="50dp" />
+
+</shape>
\ No newline at end of file

draw/src/main/res/drawable/circle_blue.xml

+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="oval">
+
+    <solid android:color="@color/color_blue" />
+    <corners android:radius="50dp" />
+
+</shape>
\ No newline at end of file

draw/src/main/res/drawable/circle_brown.xml

+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="oval">
+
+    <solid android:color="@color/color_brown" />
+    <corners android:radius="50dp" />
+
+</shape>
\ No newline at end of file

draw/src/main/res/drawable/circle_green.xml

+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="oval">
+
+    <solid android:color="@color/color_green" />
+        <corners android:radius="50dp" />
+
+</shape>
\ No newline at end of file

draw/src/main/res/drawable/circle_pink.xml

+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="oval">
+
+    <solid android:color="@color/color_pink" />
+    <corners android:radius="50dp" />
+
+</shape>
\ No newline at end of file

draw/src/main/res/drawable/circle_red.xml

+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="oval">
+
+    <solid android:color="@color/color_red" />
+    <corners android:radius="50dp" />
+
+</shape>
\ No newline at end of file

draw/src/main/res/drawable/circle_yellow.xml

+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="oval">
+
+    <solid android:color="@color/color_yellow" />
+    <corners android:radius="50dp" />
+
+</shape>
\ No newline at end of file

draw/src/main/res/drawable/ic_adjust_black_24dp.xml

+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24.0"
+    android:viewportHeight="24.0">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M12,2C6.49,2 2,6.49 2,12s4.49,10 10,10 10,-4.49 10,-10S17.51,2 12,2zM12,20c-4.41,0 -8,-3.59 -8,-8s3.59,-8 8,-8 8,3.59 8,8 -3.59,8 -8,8zM15,12c0,1.66 -1.34,3 -3,3s-3,-1.34 -3,-3 1.34,-3 3,-3 3,1.34 3,3z"/>
+</vector>
\ No newline at end of file

draw/src/main/res/drawable/ic_close_black_24dp.xml

+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+        android:width="24dp"
+        android:height="24dp"
+        android:viewportWidth="24.0"
+        android:viewportHeight="24.0">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M19,6.41L17.59,5 12,10.59 6.41,5 5,6.41 10.59,12 5,17.59 6.41,19 12,13.41 17.59,19 19,17.59 13.41,12z"/>
+</vector>

draw/src/main/res/drawable/ic_color_lens_black_24dp.xml

+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24.0"
+    android:viewportHeight="24.0">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M12,3c-4.97,0 -9,4.03 -9,9s4.03,9 9,9c0.83,0 1.5,-0.67 1.5,-1.5 0,-0.39 -0.15,-0.74 -0.39,-1.01 -0.23,-0.26 -0.38,-0.61 -0.38,-0.99 0,-0.83 0.67,-1.5 1.5,-1.5L16,16c2.76,0 5,-2.24 5,-5 0,-4.42 -4.03,-8 -9,-8zM6.5,12c-0.83,0 -1.5,-0.67 -1.5,-1.5S5.67,9 6.5,9 8,9.67 8,10.5 7.33,12 6.5,12zM9.5,8C8.67,8 8,7.33 8,6.5S8.67,5 9.5,5s1.5,0.67 1.5,1.5S10.33,8 9.5,8zM14.5,8c-0.83,0 -1.5,-0.67 -1.5,-1.5S13.67,5 14.5,5s1.5,0.67 1.5,1.5S15.33,8 14.5,8zM17.5,12c-0.83,0 -1.5,-0.67 -1.5,-1.5S16.67,9 17.5,9s1.5,0.67 1.5,1.5 -0.67,1.5 -1.5,1.5z"/>
+</vector>
\ No newline at end of file

draw/src/main/res/drawable/ic_eraser_black_24dp.xml

+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24.0"
+    android:viewportHeight="24.0">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M15.14,3C14.63,3 14.12,3.2 13.73,3.59L2.59,14.73C1.81,15.5 1.81,16.77 2.59,17.56L5.03,20H12.69L21.41,11.27C22.2,10.5 22.2,9.23 21.41,8.44L16.56,3.59C16.17,3.2 15.65,3 15.14,3M17,18L15,20H22V18"/>
+</vector>
\ No newline at end of file

draw/src/main/res/drawable/ic_opacity_black_24dp.xml

+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24.0"
+    android:viewportHeight="24.0">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M17.66,8L12,2.35 6.34,8C4.78,9.56 4,11.64 4,13.64s0.78,4.11 2.34,5.67 3.61,2.35 5.66,2.35 4.1,-0.79 5.66,-2.35S20,15.64 20,13.64 19.22,9.56 17.66,8zM6,14c0.01,-2 0.62,-3.27 1.76,-4.4L12,5.27l4.24,4.38C17.38,10.77 17.99,12 18,14H6z"/>
+</vector>
\ No newline at end of file

draw/src/main/res/drawable/ic_redo_black_24dp.xml

+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24.0"
+    android:viewportHeight="24.0">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M18.4,10.6C16.55,8.99 14.15,8 11.5,8c-4.65,0 -8.58,3.03 -9.96,7.22L3.9,16c1.05,-3.19 4.05,-5.5 7.6,-5.5 1.95,0 3.73,0.72 5.12,1.88L13,16h9V7l-3.6,3.6z"/>
+</vector>
\ No newline at end of file

draw/src/main/res/drawable/ic_send_black_24dp.xml

+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+        android:width="24dp"
+        android:height="24dp"
+        android:viewportWidth="24.0"
+        android:viewportHeight="24.0">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M2.01,21L23,12 2.01,3 2,10l15,2 -15,2z"/>
+</vector>

draw/src/main/res/drawable/ic_undo_black_24dp.xml

+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24.0"
+    android:viewportHeight="24.0">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M12.5,8c-2.65,0 -5.05,0.99 -6.9,2.6L2,7v9h9l-3.62,-3.62c1.39,-1.16 3.16,-1.88 5.12,-1.88 3.54,0 6.55,2.31 7.6,5.5l2.37,-0.78C21.08,11.03 17.15,8 12.5,8z"/>
+</vector>
\ No newline at end of file

draw/src/main/res/layout/activity_drawing.xml

+<?xml version="1.0" encoding="utf-8"?>
+<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".DrawingActivity">
+
+    <chat.rocket.android.draw.widget.CustomDrawView
+        android:id="@+id/custom_draw_view"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:background="@color/color_white" />
+
+    <ImageView
+        android:id="@+id/image_close_drawing"
+        android:layout_width="56dp"
+        android:layout_height="56dp"
+        android:src="@drawable/ic_close_black_24dp"
+        android:tint="@color/icon_color"
+        android:padding="16dp"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent"
+        android:background="@color/color_white"
+        android:foreground="?selectableItemBackgroundBorderless" />
+
+    <ImageView
+        android:id="@+id/image_send_drawing"
+        android:layout_width="56dp"
+        android:layout_height="56dp"
+        android:src="@drawable/ic_send_black_24dp"
+        android:padding="16dp"
+        android:tint="@color/colorAccent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintTop_toTopOf="parent"
+        android:background="@color/color_white"
+        android:foreground="?selectableItemBackgroundBorderless" />
+
+    <android.support.constraint.ConstraintLayout
+        android:id="@+id/draw_tools"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintBottom_toBottomOf="parent"
+        android:background="@color/color_white"
+        android:elevation="4dp"
+        android:translationY="56dp" >
+
+        <ImageView
+            android:id="@+id/image_draw_eraser"
+            android:layout_width="56dp"
+            android:layout_height="56dp"
+            android:src="@drawable/ic_eraser_black_24dp"
+            android:padding="16dp"
+            android:tint="@color/icon_color"
+            android:foreground="?selectableItemBackground"
+            app:layout_constraintHorizontal_chainStyle="packed"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintEnd_toStartOf="@id/image_draw_width"
+            app:layout_constraintTop_toTopOf="parent"/>
+
+        <ImageView
+            android:id="@+id/image_draw_width"
+            android:layout_width="56dp"
+            android:layout_height="56dp"
+            android:src="@drawable/ic_adjust_black_24dp"
+            android:padding="16dp"
+            android:tint="@color/icon_color"
+            android:foreground="?selectableItemBackground"
+            app:layout_constraintStart_toEndOf="@id/image_draw_eraser"
+            app:layout_constraintEnd_toStartOf="@id/image_draw_color"
+            app:layout_constraintTop_toTopOf="parent"/>
+
+        <ImageView
+            android:id="@+id/image_draw_color"
+            android:layout_width="56dp"
+            android:layout_height="56dp"
+            android:src="@drawable/ic_color_lens_black_24dp"
+            android:padding="16dp"
+            android:tint="@color/icon_color"
+            android:foreground="?selectableItemBackground"
+            app:layout_constraintStart_toEndOf="@id/image_draw_width"
+            app:layout_constraintEnd_toStartOf="@id/image_draw_opacity"
+            app:layout_constraintTop_toTopOf="parent"/>
+
+        <ImageView
+            android:id="@+id/image_draw_opacity"
+            android:layout_width="56dp"
+            android:layout_height="56dp"
+            android:src="@drawable/ic_opacity_black_24dp"
+            android:padding="16dp"
+            android:tint="@color/icon_color"
+            android:foreground="?selectableItemBackground"
+            app:layout_constraintStart_toEndOf="@id/image_draw_color"
+            app:layout_constraintEnd_toStartOf="@id/image_draw_undo"
+            app:layout_constraintTop_toTopOf="parent"/>
+
+        <ImageView
+            android:id="@+id/image_draw_undo"
+            android:layout_width="56dp"
+            android:layout_height="56dp"
+            android:src="@drawable/ic_undo_black_24dp"
+            android:padding="16dp"
+            android:tint="@color/icon_color"
+            android:foreground="?selectableItemBackground"
+            app:layout_constraintStart_toEndOf="@id/image_draw_opacity"
+            app:layout_constraintEnd_toStartOf="@id/image_draw_redo"
+            app:layout_constraintTop_toTopOf="parent" />
+
+        <ImageView
+            android:id="@+id/image_draw_redo"
+            android:layout_width="56dp"
+            android:layout_height="56dp"
+            android:src="@drawable/ic_redo_black_24dp"
+            android:padding="16dp"
+            android:tint="@color/icon_color"
+            android:foreground="?selectableItemBackground"
+            app:layout_constraintStart_toEndOf="@id/image_draw_undo"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintTop_toTopOf="parent" />
+
+        <SeekBar
+            android:id="@+id/seekBar_width"
+            android:layout_width="0dp"
+            android:layout_height="56dp"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintTop_toBottomOf="@id/image_draw_eraser"
+            android:progressTint="@color/colorAccent"
+            android:thumbTint="@color/colorAccent"
+            android:progress="8"
+            android:paddingStart="16dp"
+            android:paddingEnd="16dp" />
+
+        <SeekBar
+            android:id="@+id/seekBar_opacity"
+            android:layout_width="0dp"
+            android:layout_height="56dp"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintTop_toBottomOf="@id/image_draw_eraser"
+            android:progress="100"
+            android:progressTint="@color/colorAccent"
+            android:thumbTint="@color/colorAccent"
+            android:paddingStart="16dp"
+            android:paddingEnd="16dp" />
+
+        <include
+            android:id="@+id/draw_color_palette"
+            layout="@layout/color_palette_view"
+            android:layout_width="0dp"
+            android:layout_height="56dp"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintTop_toBottomOf="@id/image_draw_eraser" />
+
+    </android.support.constraint.ConstraintLayout>
+
+</android.support.constraint.ConstraintLayout>
\ No newline at end of file

draw/src/main/res/layout/color_palette_view.xml

+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="56dp"
+    android:orientation="horizontal">
+
+    <ImageView
+        android:id="@+id/image_color_black"
+        android:layout_width="48dp"
+        android:layout_height="match_parent"
+        android:src="@drawable/circle_black"
+        android:paddingTop="16dp"
+        android:paddingBottom="16dp"
+        android:paddingStart="12dp"
+        android:paddingEnd="12dp"
+        android:scaleY="1.5"
+        android:scaleX="1.5"/>
+
+    <ImageView
+        android:id="@+id/image_color_red"
+        android:layout_width="48dp"
+        android:layout_height="match_parent"
+        android:src="@drawable/circle_red"
+        android:paddingTop="16dp"
+        android:paddingBottom="16dp"
+        android:paddingStart="12dp"
+        android:paddingEnd="12dp" />
+
+    <ImageView
+        android:id="@+id/image_color_yellow"
+        android:layout_width="48dp"
+        android:layout_height="match_parent"
+        android:src="@drawable/circle_yellow"
+        android:paddingTop="16dp"
+        android:paddingBottom="16dp"
+        android:paddingStart="12dp"
+        android:paddingEnd="12dp" />
+
+    <ImageView
+        android:id="@+id/image_color_green"
+        android:layout_width="48dp"
+        android:layout_height="match_parent"
+        android:src="@drawable/circle_green"
+        android:paddingTop="16dp"
+        android:paddingBottom="16dp"
+        android:paddingStart="12dp"
+        android:paddingEnd="12dp" />
+
+    <ImageView
+        android:id="@+id/image_color_blue"
+        android:layout_width="48dp"
+        android:layout_height="match_parent"
+        android:src="@drawable/circle_blue"
+        android:paddingTop="16dp"
+        android:paddingBottom="16dp"
+        android:paddingStart="12dp"
+        android:paddingEnd="12dp" />
+
+    <ImageView
+        android:id="@+id/image_color_pink"
+        android:layout_width="48dp"
+        android:layout_height="match_parent"
+        android:src="@drawable/circle_pink"
+        android:paddingTop="16dp"
+        android:paddingBottom="16dp"
+        android:paddingStart="12dp"
+        android:paddingEnd="12dp" />
+
+    <ImageView
+        android:id="@+id/image_color_brown"
+        android:layout_width="48dp"
+        android:layout_height="match_parent"
+        android:src="@drawable/circle_brown"
+        android:paddingTop="16dp"
+        android:paddingBottom="16dp"
+        android:paddingStart="12dp"
+        android:paddingEnd="12dp" />
+</LinearLayout>
\ No newline at end of file

draw/src/main/res/values/colors.xml

+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="colorAccent">FF1976D2</color>
+    <color name="icon_color">#C2C2C2</color>
+    <color name="color_white">#FFFFFF</color>
+    <color name="color_black">#000</color>
+    <color name="color_red">#FF5252</color>
+    <color name="color_yellow">#FFEB3B</color>
+    <color name="color_green">#00C853</color>
+    <color name="color_blue">#00B0FF</color>
+    <color name="color_pink">#D500F9</color>
+    <color name="color_brown">#8D6E63</color>
+</resources>
\ No newline at end of file

draw/src/main/res/values/strings.xml

+<resources>
+    <string name="app_name">Draw</string>
+</resources>

draw/src/test/java/chat/rocket/android/draw/ExampleUnitTest.java

+package chat.rocket.android.draw;
+
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+/**
+ * Example local unit test, which will execute on the development machine (host).
+ *
+ * @see <a href="http://d.android.com/tools/testing">Testing documentation</a>
+ */
+public class ExampleUnitTest {
+    @Test
+    public void addition_isCorrect() {
+        assertEquals(4, 2 + 2);
+    }
+}
\ No newline at end of file

settings.gradle

-include ':app', ':player'
+include ':app', ':player', ':draw'
\ No newline at end of file