Improve the image editor.

A variety of improvements to the image editor, such as:

- New, fullscreen styling
- Smoother lines
- Better text and sticker handling
- Improved color picker with a history pallette
- New highlighter tool

AndroidManifest.xml

@@ -375,7 +375,7 @@
               android:configChanges="touchscreen|keyboard|keyboardHidden|orientation|screenLayout|screenSize"/>
 
     <activity android:name=".scribbles.ScribbleActivity"
-              android:theme="@style/TextSecure.LightNoActionBar"
+              android:theme="@style/TextSecure.ScribbleTheme"
               android:windowSoftInputMode="stateHidden"
               android:configChanges="touchscreen|keyboard|keyboardHidden|orientation|screenLayout|screenSize"/>
 

res/drawable/circle_white.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="oval">
+    <solid android:color="@color/white"/>
+</shape>

res/layout/item_color.xml

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<FrameLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content"
+    android:padding="6dp">
+
+    <ImageView
+        android:layout_width="20dp"
+        android:layout_height="20dp"
+        android:src="@drawable/circle_white"/>
+
+    <ImageView
+        android:id="@+id/palette_item_foreground"
+        android:layout_width="16dp"
+        android:layout_height="16dp"
+        android:src="@drawable/circle_white"
+        android:layout_gravity="center"
+        tools:tint="@color/red"/>
+
+</FrameLayout>

res/layout/scribble_activity.xml

@@ -1,26 +1,13 @@
 <?xml version="1.0" encoding="utf-8"?>
-<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<FrameLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
-              xmlns:app="http://schemas.android.com/apk/res-auto"
     android:id="@+id/activity_main"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-              android:orientation="vertical"
+    android:background="@color/black"
     tools:context="org.thoughtcrime.securesms.scribbles.ScribbleActivity">
 
-    <org.thoughtcrime.securesms.scribbles.ScribbleToolbar
-            android:id="@+id/toolbar"
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:background="@color/white"/>
-
-    <FrameLayout android:layout_weight="1"
-                  android:layout_width="match_parent"
-                  android:layout_height="0dp"
-                  android:layout_gravity="center"
-                 android:background="@color/grey_300"
-                  android:gravity="center">
-
     <org.thoughtcrime.securesms.scribbles.widget.ScribbleView
         android:id="@+id/scribble_view"
         android:layout_width="wrap_content"
@@ -28,17 +15,9 @@
         android:layout_gravity="center"
         android:gravity="center" />
 
-        <org.thoughtcrime.securesms.scribbles.widget.VerticalSlideColorPicker
-                android:id="@+id/scribble_color_picker"
-                android:layout_width="13dp"
-                android:layout_height="300dp"
-                android:layout_gravity="top|right"
-                android:layout_marginRight="25dp"
-                android:layout_marginTop="20dp"
-                app:pickerBorderWidth="1dp"
-                app:pickerBorderColor="@color/grey_600"
-                app:pickerColors="@array/scribble_colors"/>
+    <org.thoughtcrime.securesms.scribbles.ScribbleHud
+        android:id="@+id/scribble_hud"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content" />
 
 </FrameLayout>
-
-</LinearLayout>

res/layout/scribble_hud.xml

@@ -0,0 +1,89 @@
+<?xml version="1.0" encoding="utf-8"?>
+<merge
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto">
+
+    <ImageView
+        android:id="@+id/scribble_save_button"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="top|left"
+        android:src="@drawable/ic_check_white_24dp"
+        android:padding="12dp"
+        android:background="?attr/selectableItemBackgroundBorderless"/>
+
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="match_parent"
+        android:layout_gravity="right|top"
+        android:orientation="vertical"
+        android:animateLayoutChanges="true">
+
+        <ImageView
+            android:id="@+id/scribble_text_button"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:src="@drawable/ic_text_fields_white_24dp"
+            android:padding="12dp"
+            android:background="?attr/selectableItemBackgroundBorderless"/>
+
+        <ImageView
+            android:id="@+id/scribble_draw_button"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:src="@drawable/ic_brush_white_24dp"
+            android:padding="12dp"
+            android:background="?attr/selectableItemBackgroundBorderless"/>
+
+        <ImageView
+            android:id="@+id/scribble_highlight_button"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:src="@drawable/baseline_highlight_white_24"
+            android:padding="12dp"
+            android:background="?attr/selectableItemBackgroundBorderless"/>
+
+        <ImageView
+            android:id="@+id/scribble_sticker_button"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:src="@drawable/ic_tag_faces_white_24dp"
+            android:padding="12dp"
+            android:background="?attr/selectableItemBackgroundBorderless"/>
+
+        <ImageView
+            android:id="@+id/scribble_undo_button"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:src="@drawable/ic_replay_white_24dp"
+            android:padding="12dp"
+            android:background="?attr/selectableItemBackgroundBorderless"/>
+
+        <ImageView
+            android:id="@+id/scribble_delete_button"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:src="@drawable/ic_delete_white_24dp"
+            android:padding="12dp"
+            android:background="?attr/selectableItemBackgroundBorderless"/>
+
+        <org.thoughtcrime.securesms.scribbles.widget.VerticalSlideColorPicker
+            android:id="@+id/scribble_color_picker"
+            android:layout_width="26dp"
+            android:layout_height="170dp"
+            android:layout_gravity="center"
+            android:layout_marginTop="12dp"
+            app:pickerBorderWidth="4dp"
+            app:pickerBorderColor="@color/white"
+            app:pickerColors="@array/scribble_colors"/>
+
+        <android.support.v7.widget.RecyclerView
+            android:id="@+id/scribble_color_palette"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="4dp"
+            android:layout_gravity="center_horizontal"/>
+
+    </LinearLayout>
+
+</merge>

res/layout/scribble_view.xml

@@ -1,9 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <merge tools:parentTag="FrameLayout"
        xmlns:tools="http://schemas.android.com/tools"
-       xmlns:android="http://schemas.android.com/apk/res/android"
-       android:layout_width="wrap_content"
-       android:layout_height="wrap_content">
+       xmlns:android="http://schemas.android.com/apk/res/android">
 
     <ImageView android:id="@+id/image_view"
                android:layout_width="wrap_content"

res/values-v19/themes.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <style name="TextSecure.ScribbleTheme" parent="TextSecure.DarkNoActionBar">
+        <item name="android:windowNoTitle">true</item>
+        <item name="android:windowFullscreen">true</item>
+        <item name="android:windowTranslucentNavigation">true</item>
+    </style>
+</resources>

res/values/arrays.xml

@@ -273,11 +273,15 @@
     </integer-array>
 
     <array name="scribble_colors">
-        <item>#000000</item>
+        <item>#ffffff</item>
         <item>#ff0000</item>
-        <item>#ffff00</item>
-        <item>#00ffff</item>
         <item>#ff00ff</item>
+        <item>#0000ff</item>
+        <item>#00ffff</item>
+        <item>#00ff00</item>
+        <item>#ffff00</item>
+        <item>#ff5500</item>
+        <item>#000000</item>
     </array>
 
     <string-array name="pref_message_font_size_entries">

res/values/colors.xml

@@ -54,7 +54,7 @@
     <color name="import_export_touch_highlight_light">#400099cc</color>
     <color name="import_export_touch_highlight_dark">#40ffffff</color>
 
-    <color name="sticker_selected_color">#8cf437</color>
+    <color name="sticker_selected_color">#99ffffff</color>
     <color name="transparent">#00FFFFFF</color>
 
     <color name="MediaOverview_Media_selected_overlay">#88000000</color>

res/values/dimens.xml

@@ -58,7 +58,7 @@
     <dimen name="onboarding_title_size">34sp</dimen>
     <dimen name="onboarding_subtitle_size">20sp</dimen>
 
-    <dimen name="scribble_stroke_size">3dp</dimen>
+    <dimen name="scribble_stroke_size">2dp</dimen>
 
     <dimen name="floating_action_button_margin">16dp</dimen>
 

res/values/themes.xml

@@ -373,4 +373,7 @@
         <item name="android:windowBackground">@drawable/permission_rationale_dialog_corners</item>
     </style>
 
+    <style name="TextSecure.ScribbleTheme" parent="TextSecure.DarkNoActionBar">
+    </style>
+
 </resources>

src/org/thoughtcrime/securesms/scribbles/ScribbleActivity.java

@@ -5,7 +5,6 @@ import android.annotation.TargetApi;
 import android.content.Intent;
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
-import android.graphics.Color;
 import android.graphics.PointF;
 import android.net.Uri;
 import android.os.AsyncTask;
@@ -18,7 +17,6 @@ import android.view.View;
 
 import org.thoughtcrime.securesms.PassphraseRequiredActionBarActivity;
 import org.thoughtcrime.securesms.R;
-import org.thoughtcrime.securesms.crypto.MasterSecret;
 import org.thoughtcrime.securesms.mms.GlideApp;
 import org.thoughtcrime.securesms.mms.GlideRequests;
 import org.thoughtcrime.securesms.providers.PersistentBlobProvider;
@@ -40,15 +38,14 @@ import java.io.IOException;
 import java.util.concurrent.ExecutionException;
 
 @TargetApi(Build.VERSION_CODES.JELLY_BEAN)
-public class ScribbleActivity extends PassphraseRequiredActionBarActivity implements ScribbleToolbar.ScribbleToolbarListener, VerticalSlideColorPicker.OnColorChangeListener {
+public class ScribbleActivity extends PassphraseRequiredActionBarActivity implements ScribbleHud.EventListener, VerticalSlideColorPicker.OnColorChangeListener {
 
   private static final String TAG = ScribbleActivity.class.getName();
 
   public static final int SELECT_STICKER_REQUEST_CODE = 123;
   public static final int SCRIBBLE_REQUEST_CODE       = 31424;
 
-  private VerticalSlideColorPicker colorPicker;
-  private ScribbleToolbar          toolbar;
+  private ScribbleHud   scribbleHud;
   private ScribbleView  scribbleView;
   private GlideRequests glideRequests;
 
@@ -57,24 +54,21 @@ public class ScribbleActivity extends PassphraseRequiredActionBarActivity implem
     setContentView(R.layout.scribble_activity);
 
     this.glideRequests = GlideApp.with(this);
+    this.scribbleHud   = findViewById(R.id.scribble_hud);
     this.scribbleView  = findViewById(R.id.scribble_view);
-    this.toolbar       = findViewById(R.id.toolbar);
-    this.colorPicker   = findViewById(R.id.scribble_color_picker);
 
-    this.toolbar.setListener(this);
-    this.toolbar.setToolColor(Color.RED);
+    scribbleHud.setEventListener(this);
 
     scribbleView.setMotionViewCallback(motionViewCallback);
+    scribbleView.setDrawingChangedListener(() -> scribbleHud.setColorPalette(scribbleView.getUniqueColors()));
     scribbleView.setDrawingMode(false);
     scribbleView.setImage(glideRequests, getIntent().getData());
 
-    colorPicker.setOnColorChangeListener(this);
-    colorPicker.setVisibility(View.GONE);
-
-    setSupportActionBar(toolbar);
-
-    getSupportActionBar().setDisplayHomeAsUpEnabled(false);
-    getSupportActionBar().setTitle(null);
+    if (Build.VERSION.SDK_INT >= 19) {
+      getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_FULLSCREEN       |
+                                                       View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY |
+                                                       View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION);
+    }
   }
 
   private void addSticker(final Bitmap pica) {
@@ -96,6 +90,7 @@ public class ScribbleActivity extends PassphraseRequiredActionBarActivity implem
     textEntity.getLayer().getFont().setColor(selectedColor);
     textEntity.updateEntity();
     scribbleView.invalidate();
+    scribbleHud.setColorPalette(scribbleView.getUniqueColors());
   }
 
   private void startTextEntityEditing() {
@@ -119,23 +114,21 @@ public class ScribbleActivity extends PassphraseRequiredActionBarActivity implem
     TextEntity textEntity = new TextEntity(textLayer, scribbleView.getWidth(), scribbleView.getHeight());
     scribbleView.addEntityAndPosition(textEntity);
 
-    // move text sticker up so that its not hidden under keyboard
     PointF center = textEntity.absoluteCenter();
     center.y = center.y * 0.5F;
     textEntity.moveCenterTo(center);
 
-    // redraw
     scribbleView.invalidate();
 
     startTextEntityEditing();
-    changeTextEntityColor(toolbar.getToolColor());
+    changeTextEntityColor(scribbleHud.getActiveColor());
   }
 
   private TextLayer createTextLayer() {
     TextLayer textLayer = new TextLayer();
     Font font = new Font();
 
-    font.setColor(TextLayer.Limits.INITIAL_FONT_COLOR);
+    font.setColor(scribbleHud.getActiveColor());
     font.setSize(TextLayer.Limits.INITIAL_FONT_SIZE);
 
     textLayer.setFont(font);
@@ -150,7 +143,6 @@ public class ScribbleActivity extends PassphraseRequiredActionBarActivity implem
     if (resultCode == RESULT_OK) {
       if (requestCode == SELECT_STICKER_REQUEST_CODE) {
         if (data != null) {
-          toolbar.setStickerSelected(true);
           final String stickerFile = data.getStringExtra(StickerSelectActivity.EXTRA_STICKER_FILE);
 
           new AsyncTask<Void, Void, Bitmap>() {
@@ -176,44 +168,52 @@ public class ScribbleActivity extends PassphraseRequiredActionBarActivity implem
   }
 
   @Override
-  public void onBrushSelected(boolean enabled) {
-    scribbleView.setDrawingMode(enabled);
-    colorPicker.setVisibility(enabled ? View.VISIBLE : View.GONE);
-  }
+  public void onModeStarted(@NonNull ScribbleHud.Mode mode) {
+    switch (mode) {
+      case DRAW:
+        scribbleView.setDrawingMode(true);
+        scribbleView.setDrawingBrushWidth(ScribbleView.DEFAULT_BRUSH_WIDTH);
+        break;
 
-  @Override
-  public void onPaintUndo() {
-    scribbleView.undoDrawing();
-  }
+      case HIGHLIGHT:
+        scribbleView.setDrawingMode(true);
+        scribbleView.setDrawingBrushWidth(ScribbleView.DEFAULT_BRUSH_WIDTH * 3);
+        break;
 
-  @Override
-  public void onTextSelected(boolean enabled) {
-    if (enabled) {
-      addTextSticker();
+      case TEXT:
         scribbleView.setDrawingMode(false);
-      colorPicker.setVisibility(View.VISIBLE);
-    } else {
-      scribbleView.clearSelection();
-      colorPicker.setVisibility(View.GONE);
-    }
-  }
+        addTextSticker();
+        break;
 
-  @Override
-  public void onStickerSelected(boolean enabled) {
-    colorPicker.setVisibility(View.GONE);
-
-    if (!enabled) {
-      scribbleView.clearSelection();
-    } else {
+      case STICKER:
         scribbleView.setDrawingMode(false);
         Intent intent = new Intent(this, StickerSelectActivity.class);
         startActivityForResult(intent, SELECT_STICKER_REQUEST_CODE);
+        break;
+
+      case NONE:
+        scribbleView.clearSelection();
+        scribbleView.setDrawingMode(false);
+        break;
     }
   }
 
-  public void onDeleteSelected() {
+  @Override
+  public void onColorChange(int color) {
+    scribbleView.setDrawingBrushColor(color);
+    changeTextEntityColor(color);
+  }
+
+  @Override
+  public void onUndo() {
+    scribbleView.undoDrawing();
+    scribbleHud.setColorPalette(scribbleView.getUniqueColors());
+  }
+
+  @Override
+  public void onDelete() {
     scribbleView.deleteSelected();
-    colorPicker.setVisibility(View.GONE);
+    scribbleHud.setColorPalette(scribbleView.getUniqueColors());
   }
 
   @Override
@@ -250,14 +250,14 @@ public class ScribbleActivity extends PassphraseRequiredActionBarActivity implem
     @Override
     public void onEntitySelected(@Nullable MotionEntity entity) {
       if (entity == null) {
-        toolbar.setNoneSelected();
-        colorPicker.setVisibility(View.GONE);
+        scribbleHud.enterMode(ScribbleHud.Mode.NONE);
       } else if (entity instanceof TextEntity) {
-        toolbar.setTextSelected(true);
-        colorPicker.setVisibility(View.VISIBLE);
+        int textColor = ((TextEntity) entity).getLayer().getFont().getColor();
+
+        scribbleHud.enterMode(ScribbleHud.Mode.TEXT);
+        scribbleHud.setActiveColor(textColor);
       } else {
-        toolbar.setStickerSelected(true);
-        colorPicker.setVisibility(View.GONE);
+        scribbleHud.enterMode(ScribbleHud.Mode.STICKER);
       }
     }
 
@@ -266,14 +266,4 @@ public class ScribbleActivity extends PassphraseRequiredActionBarActivity implem
       startTextEntityEditing();
     }
   };
-
-  @Override
-  public void onColorChange(int color) {
-    if (color == 0) color = Color.RED;
-
-    toolbar.setToolColor(color);
-    scribbleView.setDrawingBrushColor(color);
-
-    changeTextEntityColor(color);
-  }
 }

src/org/thoughtcrime/securesms/scribbles/ScribbleHud.java

@@ -0,0 +1,250 @@
+package org.thoughtcrime.securesms.scribbles;
+
+import android.content.Context;
+import android.graphics.Color;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+import android.support.v7.widget.LinearLayoutManager;
+import android.support.v7.widget.RecyclerView;
+import android.util.AttributeSet;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.FrameLayout;
+
+import org.thoughtcrime.securesms.R;
+import org.thoughtcrime.securesms.scribbles.widget.ColorPaletteAdapter;
+import org.thoughtcrime.securesms.scribbles.widget.VerticalSlideColorPicker;
+
+import java.util.Set;
+
+/**
+ * The HUD (heads-up display) that contains all of the tools for interacting with
+ * {@link org.thoughtcrime.securesms.scribbles.widget.ScribbleView}
+ */
+public class ScribbleHud extends FrameLayout {
+
+  private View                     drawButton;
+  private View                     highlightButton;
+  private View                     textButton;
+  private View                     stickerButton;
+  private View                     undoButton;
+  private View                     deleteButton;
+  private View                     saveButton;
+  private VerticalSlideColorPicker colorPicker;
+  private RecyclerView             colorPalette;
+
+  private EventListener       eventListener;
+  private ColorPaletteAdapter colorPaletteAdapter;
+
+  public ScribbleHud(@NonNull Context context) {
+    super(context);
+    initialize();
+  }
+
+  public ScribbleHud(@NonNull Context context, @Nullable AttributeSet attrs) {
+    super(context, attrs);
+    initialize();
+  }
+
+  public ScribbleHud(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
+    super(context, attrs, defStyleAttr);
+    initialize();
+  }
+
+  private void initialize() {
+    inflate(getContext(), R.layout.scribble_hud, this);
+
+    drawButton      = findViewById(R.id.scribble_draw_button);
+    highlightButton = findViewById(R.id.scribble_highlight_button);
+    textButton      = findViewById(R.id.scribble_text_button);
+    stickerButton   = findViewById(R.id.scribble_sticker_button);
+    undoButton      = findViewById(R.id.scribble_undo_button);
+    deleteButton    = findViewById(R.id.scribble_delete_button);
+    saveButton      = findViewById(R.id.scribble_save_button);
+    colorPicker     = findViewById(R.id.scribble_color_picker);
+    colorPalette    = findViewById(R.id.scribble_color_palette);
+
+    undoButton.setOnClickListener(v -> {
+      if (eventListener != null) {
+        eventListener.onUndo();
+      }
+    });
+
+    deleteButton.setOnClickListener(v -> {
+      if (eventListener != null) {
+        eventListener.onDelete();
+      }
+      setMode(Mode.NONE);
+    });
+
+    saveButton.setOnClickListener(v -> {
+      if (eventListener != null) {
+        eventListener.onSave();
+      }
+      setMode(Mode.NONE);
+    });
+
+    colorPaletteAdapter = new ColorPaletteAdapter();
+    colorPaletteAdapter.setEventListener(colorPicker::setActiveColor);
+
+    colorPalette.setLayoutManager(new LinearLayoutManager(getContext()));
+    colorPalette.setAdapter(colorPaletteAdapter);
+
+    setMode(Mode.NONE);
+  }
+
+  public void setColorPalette(@NonNull Set<Integer> colors) {
+    colorPaletteAdapter.setColors(colors);
+  }
+
+  public void enterMode(@NonNull Mode mode) {
+    setMode(mode, false);
+  }
+
+  private void setMode(@NonNull Mode mode) {
+    setMode(mode, true);
+  }
+
+  private void setMode(@NonNull Mode mode, boolean notify) {
+    switch (mode) {
+      case NONE:      presentModeNone();      break;
+      case DRAW:      presentModeDraw();      break;
+      case HIGHLIGHT: presentModeHighlight(); break;
+      case TEXT:      presentModeText();      break;
+      case STICKER:   presentModeSticker();   break;
+    }
+
+    if (notify && eventListener != null) {
+      eventListener.onModeStarted(mode);
+    }
+  }
+
+  private void presentModeNone() {
+    drawButton.setVisibility(VISIBLE);
+    highlightButton.setVisibility(VISIBLE);
+    textButton.setVisibility(VISIBLE);
+    stickerButton.setVisibility(VISIBLE);
+
+    undoButton.setVisibility(GONE);
+    deleteButton.setVisibility(GONE);
+    colorPicker.setVisibility(GONE);
+    colorPalette.setVisibility(GONE);
+
+    drawButton.setOnClickListener(v -> setMode(Mode.DRAW));
+    highlightButton.setOnClickListener(v -> setMode(Mode.HIGHLIGHT));
+    textButton.setOnClickListener(v -> setMode(Mode.TEXT));
+    stickerButton.setOnClickListener(v -> setMode(Mode.STICKER));
+  }
+
+  private void presentModeDraw() {
+    drawButton.setVisibility(VISIBLE);
+    undoButton.setVisibility(VISIBLE);
+    colorPicker.setVisibility(VISIBLE);
+    colorPalette.setVisibility(VISIBLE);
+
+    highlightButton.setVisibility(GONE);
+    textButton.setVisibility(GONE);
+    stickerButton.setVisibility(GONE);
+    deleteButton.setVisibility(GONE);
+
+    drawButton.setOnClickListener(v -> setMode(Mode.NONE));
+
+    colorPicker.setOnColorChangeListener(standardOnColorChangeListener);
+    colorPicker.setActiveColor(Color.RED);
+  }
+
+  private void presentModeHighlight() {
+    highlightButton.setVisibility(VISIBLE);
+    undoButton.setVisibility(VISIBLE);
+    colorPicker.setVisibility(VISIBLE);
+    colorPalette.setVisibility(VISIBLE);
+
+    drawButton.setVisibility(GONE);
+    textButton.setVisibility(GONE);
+    stickerButton.setVisibility(GONE);
+    deleteButton.setVisibility(GONE);
+
+    highlightButton.setOnClickListener(v -> setMode(Mode.NONE));
+
+    colorPicker.setOnColorChangeListener(highlightOnColorChangeListener);
+    colorPicker.setActiveColor(Color.YELLOW);
+  }
+
+  private void presentModeText() {
+    textButton.setVisibility(VISIBLE);
+    deleteButton.setVisibility(VISIBLE);
+    colorPicker.setVisibility(VISIBLE);
+    colorPalette.setVisibility(VISIBLE);
+
+    drawButton.setVisibility(GONE);
+    highlightButton.setVisibility(GONE);
+    stickerButton.setVisibility(GONE);
+    undoButton.setVisibility(GONE);
+
+    textButton.setOnClickListener(v -> setMode(Mode.NONE));
+
+    colorPicker.setOnColorChangeListener(standardOnColorChangeListener);
+    colorPicker.setActiveColor(Color.WHITE);
+  }
+
+  private void presentModeSticker() {
+    stickerButton.setVisibility(VISIBLE);
+    deleteButton.setVisibility(VISIBLE);
+
+    drawButton.setVisibility(GONE);
+    highlightButton.setVisibility(GONE);
+    textButton.setVisibility(GONE);
+    undoButton.setVisibility(GONE);
+    colorPicker.setVisibility(GONE);
+    colorPalette.setVisibility(GONE);
+
+    stickerButton.setOnClickListener(v -> setMode(Mode.NONE));
+  }
+
+  public int getActiveColor() {
+    return colorPicker.getActiveColor();
+  }
+
+  public void setActiveColor(int color) {
+    colorPicker.setActiveColor(color);
+  }
+
+  public void setEventListener(@Nullable EventListener eventListener) {
+    this.eventListener = eventListener;
+  }
+
+  private final VerticalSlideColorPicker.OnColorChangeListener standardOnColorChangeListener = new VerticalSlideColorPicker.OnColorChangeListener() {
+    @Override
+    public void onColorChange(int selectedColor) {
+      if (eventListener != null) {
+        eventListener.onColorChange(selectedColor);
+      }
+    }
+  };
+
+  private final VerticalSlideColorPicker.OnColorChangeListener highlightOnColorChangeListener = new VerticalSlideColorPicker.OnColorChangeListener() {
+    @Override
+    public void onColorChange(int selectedColor) {
+      if (eventListener != null) {
+        int r = Color.red(selectedColor);
+        int g = Color.green(selectedColor);
+        int b = Color.blue(selectedColor);
+        int a = 128;
+
+        eventListener.onColorChange(Color.argb(a, r, g, b));
+      }
+    }
+  };
+
+  public enum Mode {
+    NONE, DRAW, HIGHLIGHT, TEXT, STICKER
+  }
+
+  public interface EventListener {
+    void onModeStarted(@NonNull Mode mode);
+    void onColorChange(int color);
+    void onUndo();
+    void onDelete();
+    void onSave();
+  }
+}

src/org/thoughtcrime/securesms/scribbles/ScribbleToolbar.java

@@ -1,240 +0,0 @@
-/**
- * Copyright (C) 2016 Open Whisper Systems
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-package org.thoughtcrime.securesms.scribbles;
-
-import android.animation.LayoutTransition;
-import android.annotation.TargetApi;
-import android.content.Context;
-import android.graphics.Color;
-import android.graphics.PorterDuff;
-import android.graphics.PorterDuffColorFilter;
-import android.graphics.drawable.Drawable;
-import android.os.Build;
-import android.support.annotation.Nullable;
-import android.support.v7.widget.Toolbar;
-import android.util.AttributeSet;
-import android.util.Log;
-import android.view.View;
-import android.widget.ImageView;
-import android.widget.LinearLayout;
-
-import org.thoughtcrime.securesms.R;
-
-@TargetApi(Build.VERSION_CODES.JELLY_BEAN)
-public class ScribbleToolbar extends Toolbar implements View.OnClickListener {
-
-  private enum Selected {
-    NONE,
-    STICKER,
-    TEXT,
-    BRUSH
-  }
-
-  private int foregroundSelectedTint;
-  private int foregroundUnselectedTint;
-
-  private LinearLayout toolsView;
-
-  private ImageView saveView;
-  private ImageView brushView;
-  private ImageView textView;
-  private ImageView stickerView;
-
-  private ImageView separatorView;
-
-  private ImageView undoView;
-  private ImageView deleteView;
-
-  private Drawable background;
-
-  @Nullable
-  private ScribbleToolbarListener listener;
-
-  private int      toolColor = Color.RED;
-  private Selected selected  = Selected.NONE;
-
-  public ScribbleToolbar(Context context) {
-    super(context);
-    init(context);
-  }
-
-  public ScribbleToolbar(Context context, @Nullable AttributeSet attrs) {
-    super(context, attrs);
-    init(context);
-  }
-
-  public ScribbleToolbar(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
-    super(context, attrs, defStyleAttr);
-    init(context);
-  }
-
-  private void init(Context context) {
-    inflate(context, R.layout.scribble_toolbar, this);
-
-    this.toolsView     = (LinearLayout) findViewById(R.id.tools_view);
-    this.brushView     = (ImageView) findViewById(R.id.brush_button);
-    this.textView      = (ImageView) findViewById(R.id.text_button);
-    this.stickerView   = (ImageView) findViewById(R.id.sticker_button);
-    this.separatorView = (ImageView) findViewById(R.id.separator);
-    this.saveView      = (ImageView) findViewById(R.id.save);
-
-    this.undoView   = (ImageView) findViewById(R.id.undo);
-    this.deleteView = (ImageView) findViewById(R.id.delete);
-
-    this.background               = getResources().getDrawable(R.drawable.circle_tintable);
-    this.foregroundSelectedTint   = getResources().getColor(R.color.white);
-    this.foregroundUnselectedTint = getResources().getColor(R.color.grey_800);
-
-    this.undoView.setOnClickListener(this);
-    this.brushView.setOnClickListener(this);
-    this.textView.setOnClickListener(this);
-    this.stickerView.setOnClickListener(this);
-    this.separatorView.setOnClickListener(this);
-    this.deleteView.setOnClickListener(this);
-    this.saveView.setOnClickListener(this);
-  }
-
-  public void setListener(@Nullable ScribbleToolbarListener listener) {
-    this.listener = listener;
-  }
-
-  public void setToolColor(int toolColor) {
-    this.toolColor = toolColor;
-    this.background.setColorFilter(new PorterDuffColorFilter(toolColor, PorterDuff.Mode.MULTIPLY));
-  }
-
-  public int getToolColor() {
-    return this.toolColor;
-  }
-
-  @Override
-  public void onClick(View v) {
-    this.toolsView.getLayoutTransition().enableTransitionType(LayoutTransition.CHANGING);
-
-    if (v == this.brushView) {
-      boolean enabled = selected != Selected.BRUSH;
-      setBrushSelected(enabled);
-      if (listener != null) listener.onBrushSelected(enabled);
-    } else if (v == this.stickerView) {
-      setNoneSelected();
-      if (listener != null) listener.onStickerSelected(true);
-    } else if (v == this.textView) {
-      boolean enabled = selected != Selected.TEXT;
-      setTextSelected(enabled);
-      if (listener != null) listener.onTextSelected(enabled);
-    } else if (v == this.deleteView) {
-      setNoneSelected();
-      if (listener != null) listener.onDeleteSelected();
-    } else if (v == this.undoView) {
-      if (listener != null) listener.onPaintUndo();
-    } else if (v == this.saveView) {
-      if (listener != null) listener.onSave();
-    }
-  }
-
-  private void setBrushSelected(boolean enabled) {
-    if (enabled) {
-
-      this.textView.setBackground(null);
-      this.textView.setColorFilter(new PorterDuffColorFilter(foregroundUnselectedTint, PorterDuff.Mode.MULTIPLY));
-
-      this.brushView.setBackground(background);
-      this.brushView.setColorFilter(new PorterDuffColorFilter(foregroundSelectedTint, PorterDuff.Mode.MULTIPLY));
-
-      this.stickerView.setBackground(null);
-      this.stickerView.setColorFilter(new PorterDuffColorFilter(foregroundUnselectedTint, PorterDuff.Mode.MULTIPLY));
-
-      this.separatorView.setVisibility(View.VISIBLE);
-      this.undoView.setVisibility(View.VISIBLE);
-      this.deleteView.setVisibility(View.GONE);
-
-      this.selected = Selected.BRUSH;
-    } else {
-      this.brushView.setBackground(null);
-      this.brushView.setColorFilter(new PorterDuffColorFilter(foregroundUnselectedTint, PorterDuff.Mode.MULTIPLY));
-      this.separatorView.setVisibility(View.GONE);
-      this.undoView.setVisibility(View.GONE);
-
-      this.selected = Selected.NONE;
-    }
-  }
-
-  public void setTextSelected(boolean enabled) {
-    if (enabled) {
-      this.brushView.setBackground(null);
-      this.brushView.setColorFilter(new PorterDuffColorFilter(foregroundUnselectedTint, PorterDuff.Mode.MULTIPLY));
-
-      this.textView.setBackground(background);
-      this.textView.setColorFilter(new PorterDuffColorFilter(foregroundSelectedTint, PorterDuff.Mode.MULTIPLY));
-
-      this.stickerView.setBackground(null);
-      this.stickerView.setColorFilter(new PorterDuffColorFilter(foregroundUnselectedTint, PorterDuff.Mode.MULTIPLY));
-
-      this.separatorView.setVisibility(View.VISIBLE);
-      this.undoView.setVisibility(View.GONE);
-      this.deleteView.setVisibility(View.VISIBLE);
-
-      this.selected = Selected.TEXT;
-    } else {
-      this.textView.setBackground(null);
-      this.textView.setColorFilter(new PorterDuffColorFilter(foregroundUnselectedTint, PorterDuff.Mode.MULTIPLY));
-
-      this.separatorView.setVisibility(View.GONE);
-      this.deleteView.setVisibility(View.GONE);
-
-      this.selected = Selected.NONE;
-    }
-  }
-
-  public void setStickerSelected(boolean enabled) {
-    if (enabled) {
-      this.brushView.setBackground(null);
-      this.brushView.setColorFilter(new PorterDuffColorFilter(foregroundUnselectedTint, PorterDuff.Mode.MULTIPLY));
-
-      this.textView.setBackground(null);
-      this.textView.setColorFilter(new PorterDuffColorFilter(foregroundUnselectedTint, PorterDuff.Mode.MULTIPLY));
-
-      this.separatorView.setVisibility(View.VISIBLE);
-      this.undoView.setVisibility(View.GONE);
-      this.deleteView.setVisibility(View.VISIBLE);
-
-      this.selected = Selected.STICKER;
-    } else {
-      this.separatorView.setVisibility(View.GONE);
-      this.deleteView.setVisibility(View.GONE);
-
-      this.selected = Selected.NONE;
-    }
-  }
-
-  public void setNoneSelected() {
-    setBrushSelected(false);
-    setStickerSelected(false);
-    setTextSelected(false);
-
-    this.selected = Selected.NONE;
-  }
-
-  public interface ScribbleToolbarListener {
-    public void onBrushSelected(boolean enabled);
-    public void onPaintUndo();
-    public void onTextSelected(boolean enabled);
-    public void onStickerSelected(boolean enabled);
-    public void onDeleteSelected();
-    public void onSave();
-  }
-}

src/org/thoughtcrime/securesms/scribbles/viewmodel/TextLayer.java

@@ -88,7 +88,7 @@ public class TextLayer extends Layer {
 
     float FONT_SIZE_STEP = 0.008F;
 
-    float INITIAL_FONT_SIZE = 0.075F;
+    float INITIAL_FONT_SIZE = 0.1F;
     int INITIAL_FONT_COLOR = 0xff000000;
 
     float INITIAL_SCALE = 0.8F; // set the same to avoid text scaling

src/org/thoughtcrime/securesms/scribbles/widget/CanvasView.java

@@ -20,15 +20,16 @@ import android.graphics.Path;
 import android.graphics.PorterDuff;
 import android.graphics.PorterDuffXfermode;
 import android.graphics.RectF;
-import android.graphics.Typeface;
+import android.support.annotation.NonNull;
 import android.util.AttributeSet;
-import android.util.Log;
 import android.view.MotionEvent;
 import android.view.View;
 
 import java.io.ByteArrayOutputStream;
 import java.util.ArrayList;
+import java.util.LinkedHashSet;
 import java.util.List;
+import java.util.Set;
 
 /**
  * This class defines fields and methods for drawing.
@@ -37,6 +38,8 @@ public class CanvasView extends View {
 
   private static final String TAG = CanvasView.class.getSimpleName();
 
+  public static final int DEFAULT_STROKE_WIDTH = 15;
+
   // Enumeration for Mode
   public enum Mode {
     DRAW,
@@ -78,7 +81,7 @@ public class CanvasView extends View {
   private Paint.Style paintStyle = Paint.Style.STROKE;
   private int paintStrokeColor   = Color.BLACK;
   private int paintFillColor     = Color.BLACK;
-  private float paintStrokeWidth = 15F;
+  private float paintStrokeWidth = DEFAULT_STROKE_WIDTH;
   private int opacity            = 255;
   private float blur             = 0F;
   private Paint.Cap lineCap      = Paint.Cap.ROUND;
@@ -143,7 +146,7 @@ public class CanvasView extends View {
     paint.setStyle(this.paintStyle);
     paint.setStrokeWidth(this.paintStrokeWidth);
     paint.setStrokeCap(this.lineCap);
-    paint.setStrokeJoin(Paint.Join.MITER);  // fixed
+    paint.setStrokeJoin(Paint.Join.ROUND);  // fixed
 
     if (this.mode == Mode.ERASER) {
       // Eraser
@@ -275,7 +278,9 @@ public class CanvasView extends View {
 
           switch (this.drawer) {
             case PEN :
-              path.lineTo(x, y);
+              for (int i = 0; i < event.getHistorySize(); i++) {
+                path.lineTo(event.getHistoricalX(i), event.getHistoricalY(i));
+              }
               break;
             case LINE :
               path.reset();
@@ -770,4 +775,14 @@ public class CanvasView extends View {
     return this.getBitmapAsByteArray(CompressFormat.PNG, 100);
   }
 
+  public @NonNull Set<Integer> getUniqueColors() {
+    Set<Integer> colors = new LinkedHashSet<>();
+
+    for (int i = 1; i < paintLists.size() && i < historyPointer; i++) {
+      int color = paintLists.get(i).getColor();
+      colors.add(Color.rgb(Color.red(color), Color.green(color), Color.blue(color)));
+    }
+
+    return colors;
+  }
 }

src/org/thoughtcrime/securesms/scribbles/widget/ColorPaletteAdapter.java

@@ -0,0 +1,73 @@
+package org.thoughtcrime.securesms.scribbles.widget;
+
+import android.graphics.PorterDuff;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+import android.support.v7.widget.RecyclerView;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.ImageView;
+
+import org.thoughtcrime.securesms.R;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+public class ColorPaletteAdapter extends RecyclerView.Adapter<ColorPaletteAdapter.ColorViewHolder> {
+
+  private final List<Integer> colors = new ArrayList<>();
+
+  private EventListener eventListener;
+
+  @Override
+  public ColorViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
+    return new ColorViewHolder(LayoutInflater.from(parent.getContext()).inflate(R.layout.item_color, parent, false));
+  }
+
+  @Override
+  public void onBindViewHolder(ColorViewHolder holder, int position) {
+    holder.bind(colors.get(position), eventListener);
+  }
+
+  @Override
+  public int getItemCount() {
+    return colors.size();
+  }
+
+  public void setColors(@NonNull Collection<Integer> colors) {
+    this.colors.clear();
+    this.colors.addAll(colors);
+
+    notifyDataSetChanged();
+  }
+
+  public void setEventListener(@Nullable EventListener eventListener) {
+    this.eventListener = eventListener;
+
+    notifyDataSetChanged();
+  }
+
+  public interface EventListener {
+    void onColorSelected(int color);
+  }
+
+  static class ColorViewHolder extends RecyclerView.ViewHolder {
+
+    ImageView foreground;
+
+    ColorViewHolder(View itemView) {
+      super(itemView);
+      foreground = itemView.findViewById(R.id.palette_item_foreground);
+    }
+
+    void bind(int color, @Nullable EventListener eventListener) {
+      foreground.setColorFilter(color, PorterDuff.Mode.SRC_IN);
+
+      if (eventListener != null) {
+        itemView.setOnClickListener(v -> eventListener.onColorSelected(color));
+      }
+    }
+  }
+}

src/org/thoughtcrime/securesms/scribbles/widget/MotionView.java

@@ -36,6 +36,7 @@ import android.support.v4.view.ViewCompat;
 import android.text.Editable;
 import android.text.InputType;
 import android.text.Selection;
+import android.text.TextUtils;
 import android.text.TextWatcher;
 import android.util.AttributeSet;
 import android.util.Log;
@@ -56,7 +57,9 @@ import org.thoughtcrime.securesms.scribbles.widget.entity.MotionEntity;
 import org.thoughtcrime.securesms.scribbles.widget.entity.TextEntity;
 
 import java.util.ArrayList;
+import java.util.LinkedHashSet;
 import java.util.List;
+import java.util.Set;
 
 public class MotionView  extends FrameLayout implements TextWatcher {
 
@@ -182,6 +185,18 @@ public class MotionView  extends FrameLayout implements TextWatcher {
     }
   }
 
+  public @NonNull Set<Integer> getUniqueColors() {
+    Set<Integer> colors = new LinkedHashSet<>();
+
+    for (MotionEntity entity : entities) {
+      if (entity instanceof TextEntity) {
+        colors.add(((TextEntity) entity).getLayer().getFont().getColor());
+      }
+    }
+
+    return colors;
+  }
+
   private void initEntityBorder(@NonNull MotionEntity entity ) {
     // init stroke
     int strokeSize = getResources().getDimensionPixelSize(R.dimen.scribble_stroke_size);
@@ -274,13 +289,16 @@ public class MotionView  extends FrameLayout implements TextWatcher {
   }
 
   private void selectEntity(@Nullable MotionEntity entity, boolean updateCallback) {
-    if (selectedEntity != null) {
+    if (selectedEntity != null && entity != selectedEntity) {
       selectedEntity.setIsSelected(false);
 
       if (selectedEntity instanceof TextEntity) {
+        if (TextUtils.isEmpty(((TextEntity) selectedEntity).getLayer().getText())) {
+          deletedSelectedEntity();
+        } else {
           editText.clearComposingText();
           editText.clearFocus();
-
+        }
         InputMethodManager imm = (InputMethodManager) getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
         imm.hideSoftInputFromWindow(editText.getWindowToken(), 0);
       }
@@ -413,6 +431,12 @@ public class MotionView  extends FrameLayout implements TextWatcher {
       updateSelectionOnTap(e);
       return true;
     }
+
+    @Override
+    public boolean onDown(MotionEvent e) {
+      updateSelectionOnTap(e);
+      return false;
+    }
   }
 
   private class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener {

src/org/thoughtcrime/securesms/scribbles/widget/ScribbleView.java

@@ -21,18 +21,22 @@ import android.annotation.TargetApi;
 import android.content.Context;
 import android.graphics.Bitmap;
 import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.drawable.Drawable;
 import android.net.Uri;
-import android.os.AsyncTask;
 import android.os.Build;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.util.AttributeSet;
-import android.util.Log;
+import android.view.MotionEvent;
+import android.view.View;
 import android.widget.FrameLayout;
 import android.widget.ImageView;
 
 import com.bumptech.glide.load.engine.DiskCacheStrategy;
+import com.bumptech.glide.request.target.SimpleTarget;
 import com.bumptech.glide.request.target.Target;
+import com.bumptech.glide.request.transition.Transition;
 
 import org.thoughtcrime.securesms.R;
 import org.thoughtcrime.securesms.mms.DecryptableStreamUriLoader.DecryptableUri;
@@ -43,12 +47,15 @@ import org.thoughtcrime.securesms.util.Util;
 import org.thoughtcrime.securesms.util.concurrent.ListenableFuture;
 import org.thoughtcrime.securesms.util.concurrent.SettableFuture;
 
-import java.util.concurrent.ExecutionException;
+import java.util.LinkedHashSet;
+import java.util.Set;
 
 public class ScribbleView extends FrameLayout {
 
   private static final String TAG = ScribbleView.class.getSimpleName();
 
+  public static final int DEFAULT_BRUSH_WIDTH = CanvasView.DEFAULT_STROKE_WIDTH;
+
   private ImageView imageView;
   private MotionView motionView;
   private CanvasView canvasView;
@@ -85,7 +92,6 @@ public class ScribbleView extends FrameLayout {
                  .into(imageView);
   }
 
-  @SuppressLint("StaticFieldLeak")
   public @NonNull ListenableFuture<Bitmap> getRenderedImage(@NonNull GlideRequests glideRequests) {
     final SettableFuture<Bitmap> future      = new SettableFuture<>();
     final Context                context     = getContext();
@@ -96,10 +102,6 @@ public class ScribbleView extends FrameLayout {
       return future;
     }
 
-    new AsyncTask<Void, Void, Bitmap>() {
-      @Override
-      protected @Nullable Bitmap doInBackground(Void... params) {
-        try {
     int width  = Target.SIZE_ORIGINAL;
     int height = Target.SIZE_ORIGINAL;
 
@@ -108,31 +110,25 @@ public class ScribbleView extends FrameLayout {
       height = 768;
     }
 
-          return glideRequests.asBitmap()
+    glideRequests.asBitmap()
                  .load(new DecryptableUri(imageUri))
                  .diskCacheStrategy(DiskCacheStrategy.NONE)
                  .skipMemoryCache(true)
-                              .into(width, height)
-                              .get();
-        } catch (InterruptedException | ExecutionException e) {
-          Log.w(TAG, e);
-          return null;
-        }
-      }
-
+                 .override(width, height)
+                 .into(new SimpleTarget<Bitmap>() {
                    @Override
-      protected void onPostExecute(@Nullable Bitmap bitmap) {
-        if (bitmap == null) {
-          future.set(null);
-          return;
-        }
-
+                   public void onResourceReady(@NonNull Bitmap bitmap, @Nullable Transition<? super Bitmap> transition) {
                      Canvas canvas = new Canvas(bitmap);
                      motionView.render(canvas);
                      canvasView.render(canvas);
                      future.set(bitmap);
                    }
-    }.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
+
+                   @Override
+                   public void onLoadFailed(@Nullable Drawable errorDrawable) {
+                     future.set(null);
+                   }
+               });
 
     return future;
   }
@@ -149,6 +145,18 @@ public class ScribbleView extends FrameLayout {
     this.motionView.setMotionViewCallback(callback);
   }
 
+  @SuppressLint("ClickableViewAccessibility")
+  public void setDrawingChangedListener(@Nullable DrawingChangedListener listener) {
+    this.canvasView.setOnTouchListener((v, event) -> {
+      if (event.getAction() == MotionEvent.ACTION_UP || event.getAction() == MotionEvent.ACTION_CANCEL) {
+        if (listener != null) {
+          listener.onDrawingChanged();
+        }
+      }
+      return false;
+    });
+  }
+
   public void setDrawingMode(boolean enabled) {
     this.canvasView.setActive(enabled);
     if (enabled) this.motionView.unselectEntity();
@@ -157,6 +165,11 @@ public class ScribbleView extends FrameLayout {
   public void setDrawingBrushColor(int color) {
     this.canvasView.setPaintFillColor(color);
     this.canvasView.setPaintStrokeColor(color);
+    this.canvasView.setOpacity(Color.alpha(color));
+  }
+
+  public void setDrawingBrushWidth(int width) {
+    this.canvasView.setPaintStrokeWidth(width);
   }
 
   public void addEntityAndPosition(MotionEntity entity) {
@@ -183,6 +196,15 @@ public class ScribbleView extends FrameLayout {
     this.motionView.startEditing(entity);
   }
 
+  public @NonNull Set<Integer> getUniqueColors() {
+    Set<Integer> colors = new LinkedHashSet<>();
+
+    colors.addAll(motionView.getUniqueColors());
+    colors.addAll(canvasView.getUniqueColors());
+
+    return colors;
+  }
+
   @Override
   public void onMeasure(int width, int height) {
     super.onMeasure(width, height);
@@ -196,4 +218,7 @@ public class ScribbleView extends FrameLayout {
                        MeasureSpec.makeMeasureSpec(imageView.getMeasuredHeight(), MeasureSpec.EXACTLY));
   }
 
+  public interface DrawingChangedListener {
+    void onDrawingChanged();
+  }
 }

src/org/thoughtcrime/securesms/scribbles/widget/VerticalSlideColorPicker.java

@@ -43,8 +43,12 @@ import org.thoughtcrime.securesms.R;
 
 public class VerticalSlideColorPicker extends View {
 
+  private static final float INDICATOR_TO_BAR_WIDTH_RATIO = 0.8f;
+
   private Paint  paint;
   private Paint  strokePaint;
+  private Paint  indicatorStrokePaint;
+  private Paint  indicatorFillPaint;
   private Path   path;
   private Bitmap bitmap;
   private Canvas bitmapCanvas;
@@ -59,8 +63,12 @@ public class VerticalSlideColorPicker extends View {
 
   private int     borderColor;
   private float   borderWidth;
+  private float   indicatorRadius;
   private int[]   colors;
 
+  private int     touchY;
+  private int     activeColor;
+
   public VerticalSlideColorPicker(Context context) {
     super(context);
     init();
@@ -110,6 +118,13 @@ public class VerticalSlideColorPicker extends View {
     strokePaint.setColor(borderColor);
     strokePaint.setAntiAlias(true);
     strokePaint.setStrokeWidth(borderWidth);
+
+    indicatorStrokePaint = new Paint(strokePaint);
+    indicatorStrokePaint.setStrokeWidth(borderWidth / 2);
+
+    indicatorFillPaint = new Paint();
+    indicatorFillPaint.setStyle(Paint.Style.FILL);
+    indicatorFillPaint.setAntiAlias(true);
   }
 
   @Override
@@ -126,20 +141,27 @@ public class VerticalSlideColorPicker extends View {
     bitmapCanvas.drawPath(path, paint);
 
     canvas.drawBitmap(bitmap, 0, 0, null);
+
+    touchY = Math.max((int) colorPickerBody.top, touchY);
+
+    indicatorFillPaint.setColor(activeColor);
+    canvas.drawCircle(centerX, touchY, indicatorRadius, indicatorFillPaint);
+    canvas.drawCircle(centerX, touchY, indicatorRadius, indicatorStrokePaint);
   }
 
   @Override
   public boolean onTouchEvent(MotionEvent event) {
+    touchY = (int) Math.min(event.getY(), colorPickerBody.bottom);
+    touchY = (int) Math.max(colorPickerBody.top, touchY);
 
-    float yPos = Math.min(event.getY(), colorPickerBody.bottom);
-    yPos = Math.max(colorPickerBody.top, yPos);
-
-    int selectedColor = bitmap.getPixel(viewWidth/2, (int) yPos);
+    activeColor = bitmap.getPixel(viewWidth/2, touchY);
 
     if (onColorChangeListener != null) {
-      onColorChangeListener.onColorChange(selectedColor);
+      onColorChangeListener.onColorChange(activeColor);
     }
 
+    invalidate();
+
     return true;
   }
 
@@ -150,8 +172,11 @@ public class VerticalSlideColorPicker extends View {
     viewWidth  = w;
     viewHeight = h;
 
+    int barWidth = (int) (viewWidth * INDICATOR_TO_BAR_WIDTH_RATIO);
+
     centerX           = viewWidth / 2;
-    colorPickerRadius = (viewWidth / 2) - borderWidth;
+    indicatorRadius   = (viewWidth / 2) - borderWidth;
+    colorPickerRadius = (barWidth / 2) - borderWidth;
 
     colorPickerBody   = new RectF(centerX - colorPickerRadius, borderWidth + colorPickerRadius, centerX + colorPickerRadius, viewHeight - (borderWidth + colorPickerRadius));
 
@@ -164,8 +189,6 @@ public class VerticalSlideColorPicker extends View {
 
     bitmap       = Bitmap.createBitmap(viewWidth, viewHeight, Bitmap.Config.ARGB_8888);
     bitmapCanvas = new Canvas(bitmap);
-
-    resetToDefault();
   }
 
   public void setBorderColor(int borderColor) {
@@ -183,20 +206,29 @@ public class VerticalSlideColorPicker extends View {
     invalidate();
   }
 
-  public void resetToDefault() {
+  public void setActiveColor(int color) {
+    activeColor = color;
+
+    if (colorPickerBody != null) {
+      touchY = (int) colorPickerBody.top;
+    }
+
     if (onColorChangeListener != null) {
-      onColorChangeListener.onColorChange(Color.RED);
+      onColorChangeListener.onColorChange(color);
     }
 
     invalidate();
   }
 
+  public int getActiveColor() {
+    return activeColor;
+  }
+
   public void setOnColorChangeListener(OnColorChangeListener onColorChangeListener) {
     this.onColorChangeListener = onColorChangeListener;
   }
 
   public interface OnColorChangeListener {
-
     void onColorChange(int selectedColor);
   }
 }