Add several ui polish for media-send.

feature/media-send/src/main/java/org/signal/mediasend/screens/edit/image/ImageEditor.kt

@@ -14,6 +14,7 @@ import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.text.BasicTextField
 import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.material3.MaterialTheme
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.DisposableEffect
 import androidx.compose.runtime.LaunchedEffect
@@ -28,6 +29,7 @@ import androidx.compose.ui.focus.FocusRequester
 import androidx.compose.ui.focus.focusRequester
 import androidx.compose.ui.geometry.Offset
 import androidx.compose.ui.graphics.nativeCanvas
+import androidx.compose.ui.graphics.toArgb
 import androidx.compose.ui.hapticfeedback.HapticFeedbackType
 import androidx.compose.ui.input.pointer.changedToDown
 import androidx.compose.ui.input.pointer.pointerInput
@@ -53,6 +55,9 @@ internal fun ImageEditor(
   val state = controller.imageEditorState
   val hapticFeedback = LocalHapticFeedback.current
 
+  // Masks everything outside the image, so it has to match the surface the editor is drawn on to read as a background.
+  val blackoutColor = MaterialTheme.colorScheme.surface.toArgb()
+
   DisposableEffect(state) {
     state.attach()
     onDispose { state.detach() }
@@ -76,6 +81,7 @@ internal fun ImageEditor(
 
       val nativeCanvas = drawContext.canvas.nativeCanvas
       val rendererContext = state.getOrCreateRendererContext(context, nativeCanvas)
+      rendererContext.setBlackoutColor(blackoutColor)
       rendererContext.save()
       try {
         rendererContext.canvasMatrix.initial(state.viewMatrix)

feature/media-send/src/main/java/org/signal/mediasend/screens/edit/image/ImageEditorToolbar.kt

@@ -78,13 +78,13 @@ private fun ImageEditorNoneStateToolbar(
 ) {
   MediaEditorToolbar(modifier) {
     MediaEditorToolbarButton(
-      imageVector = SignalIcons.BrushPen.imageVector,
-      onClick = imageEditorController::beginDrawEdit
+      imageVector = SignalIcons.CropRotate.imageVector,
+      onClick = imageEditorController::beginCropAndRotateEdit
     )
 
     MediaEditorToolbarButton(
-      imageVector = SignalIcons.CropRotate.imageVector,
-      onClick = imageEditorController::beginCropAndRotateEdit
+      imageVector = SignalIcons.BrushPen.imageVector,
+      onClick = imageEditorController::beginDrawEdit
     )
 
     MediaEditorToolbarSharedButtons(

lib/image-editor/src/main/java/org/signal/imageeditor/core/RendererContext.java

@@ -2,6 +2,7 @@ package org.signal.imageeditor.core;
 
 import android.content.Context;
 import android.graphics.Canvas;
+import android.graphics.Color;
 import android.graphics.Matrix;
 import android.graphics.Paint;
 import android.graphics.Point;
@@ -9,8 +10,10 @@ import android.graphics.RectF;
 import android.graphics.Typeface;
 import android.os.Build;
 
+import androidx.annotation.ColorInt;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
+import androidx.core.graphics.ColorUtils;
 
 import org.signal.imageeditor.core.model.EditorElement;
 
@@ -50,6 +53,10 @@ public final class RendererContext {
 
   private boolean isEditing = true;
 
+  @ColorInt
+  @Nullable
+  private Integer blackoutColor;
+
   private List<EditorElement> children = Collections.emptyList();
   private Paint               maskPaint;
 
@@ -98,6 +105,24 @@ public final class RendererContext {
     return Math.max(0, Math.min(255, (int) (fade * alpha)));
   }
 
+  /**
+   * Overrides the blackout color the model was created with for this render, so that a caller whose background can
+   * change after the model exists -- a theme switch, for example -- can keep the two in step. Pass null to fall back to
+   * the model's own color.
+   */
+  public void setBlackoutColor(@ColorInt @Nullable Integer blackoutColor) {
+    this.blackoutColor = blackoutColor;
+  }
+
+  /**
+   * Resolves a color derived from the model's blackout color against any override set for this render, preserving the
+   * alpha the caller baked in.
+   */
+  @ColorInt
+  public int resolveBlackoutColor(@ColorInt int modelColor) {
+    return blackoutColor == null ? modelColor : ColorUtils.setAlphaComponent(blackoutColor, Color.alpha(modelColor));
+  }
+
   /**
    * Persist the current state on to a stack, must be complimented by a call to {@link #restore()}.
    */

lib/image-editor/src/main/java/org/signal/imageeditor/core/renderers/CropAreaRenderer.java

@@ -43,7 +43,7 @@ public final class CropAreaRenderer implements Renderer {
     Resources resources = rendererContext.context.getResources();
 
     canvas.clipPath(cropClipPath);
-    canvas.drawColor(color);
+    canvas.drawColor(rendererContext.resolveBlackoutColor(color));
 
     rendererContext.mapRect(dst, Bounds.FULL_BOUNDS);
 

lib/image-editor/src/main/java/org/signal/imageeditor/core/renderers/FillRenderer.java

@@ -35,7 +35,7 @@ public final class FillRenderer implements Renderer {
     path.addRoundRect(dst, DimensionUnit.DP.toPixels(18), DimensionUnit.DP.toPixels(18), Path.Direction.CW);
 
     rendererContext.canvas.clipPath(path);
-    rendererContext.canvas.drawColor(color);
+    rendererContext.canvas.drawColor(rendererContext.resolveBlackoutColor(color));
     rendererContext.canvas.restore();
   }
 

lib/image-editor/src/main/java/org/signal/imageeditor/core/renderers/InverseFillRenderer.java

@@ -35,7 +35,7 @@ public final class InverseFillRenderer implements Renderer {
     path.addRoundRect(dst, DimensionUnit.DP.toPixels(18), DimensionUnit.DP.toPixels(18), Path.Direction.CW);
 
     rendererContext.canvas.clipPath(path);
-    rendererContext.canvas.drawColor(color);
+    rendererContext.canvas.drawColor(rendererContext.resolveBlackoutColor(color));
     rendererContext.canvas.restore();
   }