Implement overflow:visible/hidden attribute (defaults to visible)

Summary:
Prior to this patch DrawCommands weren't get clipped by parent DrawCommands at all. For example, a <View> element with size 200x200 with overflow:hidden should clip its child which is 400x400, but this didn't happen. However, if parent <View> would mount to an Android View, it would clip the child regardless of the overflow attribute value (because Android Views always clip whatever is drawing inside that View against its boundaries).

This diff is fixing these issue, implementing overflow attribute support and making clipping behavior consistent between nodes that mount to View and nodes that don't.

Reviewed By: ahmedre

Differential Revision: D2768643

ReactAndroid/src/main/java/com/facebook/react/flat/AbstractDrawCommand.java

@@ -9,6 +9,8 @@
 
 package com.facebook.react.flat;
 
+import android.graphics.Canvas;
+
 /**
  * Base class for all DrawCommands. Becomes immutable once it has its bounds set. Until then, a
  * subclass is able to mutate any of its properties (e.g. updating Layout in DrawTextLayout).
@@ -22,8 +24,24 @@ package com.facebook.react.flat;
   private float mTop;
   private float mRight;
   private float mBottom;
+  private float mClipLeft;
+  private float mClipTop;
+  private float mClipRight;
+  private float mClipBottom;
   private boolean mFrozen;
 
+  @Override
+  public final void draw(FlatViewGroup parent, Canvas canvas) {
+    if (shouldClip()) {
+      canvas.save();
+      canvas.clipRect(mClipLeft, mClipTop, mClipRight, mClipBottom);
+      onDraw(canvas);
+      canvas.restore();
+    } else {
+      onDraw(canvas);
+    }
+  }
+
   /**
    * Updates boundaries of the AbstractDrawCommand and freezes it.
    * Will return a frozen copy if the current AbstractDrawCommand cannot be mutated.
@@ -32,16 +50,27 @@ package com.facebook.react.flat;
       float left,
       float top,
       float right,
-      float bottom) {
+      float bottom,
+      float clipLeft,
+      float clipTop,
+      float clipRight,
+      float clipBottom) {
     if (mFrozen) {
       // see if we can reuse it
-      if (boundsMatch(left, top, right, bottom)) {
+      boolean boundsMatch = boundsMatch(left, top, right, bottom);
+      boolean clipBoundsMatch = clipBoundsMatch(clipLeft, clipTop, clipRight, clipBottom);
+      if (boundsMatch && clipBoundsMatch) {
         return this;
       }
 
       try {
         AbstractDrawCommand copy = (AbstractDrawCommand) clone();
+        if (!boundsMatch) {
           copy.setBounds(left, top, right, bottom);
+        }
+        if (!clipBoundsMatch) {
+          copy.setClipBounds(clipLeft, clipTop, clipRight, clipBottom);
+        }
         return copy;
       } catch (CloneNotSupportedException e) {
         // This should not happen since AbstractDrawCommand implements Cloneable
@@ -50,6 +79,7 @@ package com.facebook.react.flat;
     }
 
     setBounds(left, top, right, bottom);
+    setClipBounds(clipLeft, clipTop, clipRight, clipBottom);
     mFrozen = true;
     return this;
   }
@@ -103,6 +133,12 @@ package com.facebook.react.flat;
     return mBottom;
   }
 
+  protected abstract void onDraw(Canvas canvas);
+
+  protected boolean shouldClip() {
+    return mLeft != mClipLeft || mTop != mClipTop || mRight != mClipRight || mBottom != mClipBottom;
+  }
+
   protected void onBoundsChanged() {
   }
 
@@ -118,10 +154,26 @@ package com.facebook.react.flat;
     onBoundsChanged();
   }
 
+  private void setClipBounds(float clipLeft, float clipTop, float clipRight, float clipBottom) {
+    mClipLeft = clipLeft;
+    mClipTop = clipTop;
+    mClipRight = clipRight;
+    mClipBottom = clipBottom;
+  }
+
   /**
    * Returns true if boundaries match and don't need to be updated. False otherwise.
    */
   private boolean boundsMatch(float left, float top, float right, float bottom) {
     return mLeft == left && mTop == top && mRight == right && mBottom == bottom;
   }
+
+  private boolean clipBoundsMatch(
+      float clipLeft,
+      float clipTop,
+      float clipRight,
+      float clipBottom) {
+    return mClipLeft == clipLeft && mClipTop == clipTop &&
+        mClipRight == clipRight && mClipBottom == clipBottom;
+  }
 }

ReactAndroid/src/main/java/com/facebook/react/flat/DrawBackgroundColor.java

@@ -26,7 +26,7 @@ import android.graphics.Paint;
   }
 
   @Override
-  public void draw(FlatViewGroup parent, Canvas canvas) {
+  public void onDraw(Canvas canvas) {
     PAINT.setColor(mBackgroundColor);
     canvas.drawRect(getLeft(), getTop(), getRight(), getBottom(), PAINT);
   }

ReactAndroid/src/main/java/com/facebook/react/flat/DrawBorder.java

@@ -169,7 +169,7 @@ import com.facebook.csslayout.Spacing;
   }
 
   @Override
-  public void draw(FlatViewGroup parent, Canvas canvas) {
+  protected void onDraw(Canvas canvas) {
     if (getBorderRadius() >= 0.5f) {
       drawRoundedBorders(canvas);
     } else {

ReactAndroid/src/main/java/com/facebook/react/flat/DrawImageWithPipeline.java

@@ -80,7 +80,7 @@ import com.facebook.react.views.image.ImageResizeMode;
   }
 
   @Override
-  public void draw(FlatViewGroup parent, Canvas canvas) {
+  protected void onDraw(Canvas canvas) {
     Bitmap bitmap = Assertions.assumeNotNull(mBitmapRequestHelper).getBitmap();
     if (bitmap == null) {
       return;
@@ -88,11 +88,6 @@ import com.facebook.react.views.image.ImageResizeMode;
 
     PAINT.setColorFilter(mColorFilter);
 
-    if (mForceClip) {
-      canvas.save();
-      canvas.clipRect(getLeft(), getTop(), getRight(), getBottom());
-    }
-
     if (getBorderRadius() < 0.5f) {
       canvas.drawBitmap(bitmap, mTransform, PAINT);
     } else {
@@ -105,10 +100,11 @@ import com.facebook.react.views.image.ImageResizeMode;
     }
 
     drawBorders(canvas);
-
-    if (mForceClip) {
-      canvas.restore();
   }
+
+  @Override
+  protected boolean shouldClip() {
+    return mForceClip || super.shouldClip();
   }
 
   @Override

ReactAndroid/src/main/java/com/facebook/react/flat/DrawTextLayout.java

@@ -35,7 +35,7 @@ import android.text.Layout;
   }
 
   @Override
-  public void draw(FlatViewGroup parent, Canvas canvas) {
+  protected void onDraw(Canvas canvas) {
     float left = getLeft();
     float top = getTop();
 

ReactAndroid/src/main/java/com/facebook/react/flat/FlatShadowNode.java

@@ -47,6 +47,7 @@ import com.facebook.react.uimanager.ViewProps;
   private boolean mBackingViewIsCreated;
   private @Nullable DrawBackgroundColor mDrawBackground;
   private int mMoveToIndexInParent;
+  private boolean mIsOverflowVisible = true;
 
   /* package */ void handleUpdateProperties(CatalystStylesDiffMap styles) {
     if (!mountsToView()) {
@@ -72,13 +73,21 @@ import com.facebook.react.uimanager.ViewProps;
       float left,
       float top,
       float right,
-      float bottom) {
+      float bottom,
+      float clipLeft,
+      float clipTop,
+      float clipRight,
+      float clipBottom) {
     if (mDrawBackground != null) {
       mDrawBackground = (DrawBackgroundColor) mDrawBackground.updateBoundsAndFreeze(
           left,
           top,
           right,
-          bottom);
+          bottom,
+          clipLeft,
+          clipTop,
+          clipRight,
+          clipBottom);
       stateBuilder.addDrawCommand(mDrawBackground);
     }
   }
@@ -89,6 +98,16 @@ import com.facebook.react.uimanager.ViewProps;
     invalidate();
   }
 
+  @ReactProp(name = "overflow")
+  public void setOverflow(String overflow) {
+    mIsOverflowVisible = "visible".equals(overflow);
+    invalidate();
+  }
+
+  public final boolean isOverflowVisible() {
+    return mIsOverflowVisible;
+  }
+
   @Override
   public final int getScreenX() {
     return mViewLeft;

ReactAndroid/src/main/java/com/facebook/react/flat/FlatViewGroup.java

@@ -62,6 +62,7 @@ import com.facebook.react.uimanager.ReactCompoundView;
 
   /* package */ FlatViewGroup(Context context) {
     super(context);
+    setClipChildren(false);
   }
 
   @Override

ReactAndroid/src/main/java/com/facebook/react/flat/RCTImageView.java

@@ -54,15 +54,32 @@ import com.facebook.react.views.image.ImageResizeMode;
       float left,
       float top,
       float right,
-      float bottom) {
-    super.collectState(stateBuilder, left, top, right, bottom);
+      float bottom,
+      float clipLeft,
+      float clipTop,
+      float clipRight,
+      float clipBottom) {
+    super.collectState(
+        stateBuilder,
+        left,
+        top,
+        right,
+        bottom,
+        clipLeft,
+        clipTop,
+        clipRight,
+        clipBottom);
 
     if (mDrawImage.hasImageRequest()) {
       mDrawImage = (T) mDrawImage.updateBoundsAndFreeze(
           left,
           top,
           right,
-          bottom);
+          bottom,
+          clipLeft,
+          clipTop,
+          clipRight,
+          clipBottom);
       stateBuilder.addDrawCommand(mDrawImage);
       stateBuilder.addAttachDetachListener(mDrawImage);
     }

ReactAndroid/src/main/java/com/facebook/react/flat/RCTText.java

@@ -137,8 +137,22 @@ import com.facebook.react.uimanager.ViewProps;
       float left,
       float top,
       float right,
-      float bottom) {
-    super.collectState(stateBuilder, left, top, right, bottom);
+      float bottom,
+      float clipLeft,
+      float clipTop,
+      float clipRight,
+      float clipBottom) {
+
+    super.collectState(
+        stateBuilder,
+        left,
+        top,
+        right,
+        bottom,
+        clipLeft,
+        clipRight,
+        clipTop,
+        clipBottom);
 
     if (mText == null) {
       // nothing to draw (empty text).
@@ -158,7 +172,15 @@ import com.facebook.react.uimanager.ViewProps;
           INCLUDE_PADDING));
     }
 
-    mDrawCommand = (DrawTextLayout) mDrawCommand.updateBoundsAndFreeze(left, top, right, bottom);
+    mDrawCommand = (DrawTextLayout) mDrawCommand.updateBoundsAndFreeze(
+        left,
+        top,
+        right,
+        bottom,
+        clipLeft,
+        clipTop,
+        clipRight,
+        clipBottom);
     stateBuilder.addDrawCommand(mDrawCommand);
   }
 

ReactAndroid/src/main/java/com/facebook/react/flat/RCTView.java

@@ -27,11 +27,32 @@ import com.facebook.react.uimanager.ViewProps;
       float left,
       float top,
       float right,
-      float bottom) {
-    super.collectState(stateBuilder, left, top, right, bottom);
+      float bottom,
+      float clipLeft,
+      float clipTop,
+      float clipRight,
+      float clipBottom) {
+    super.collectState(
+        stateBuilder,
+        left,
+        top,
+        right,
+        bottom,
+        clipLeft,
+        clipTop,
+        clipRight,
+        clipBottom);
 
     if (mDrawBorder != null) {
-      mDrawBorder = (DrawBorder) mDrawBorder.updateBoundsAndFreeze(left, top, right, bottom);
+      mDrawBorder = (DrawBorder) mDrawBorder.updateBoundsAndFreeze(
+          left,
+          top,
+          right,
+          bottom,
+          clipLeft,
+          clipTop,
+          clipRight,
+          clipBottom);
       stateBuilder.addDrawCommand(mDrawBorder);
     }
   }

ReactAndroid/src/main/java/com/facebook/react/flat/StateBuilder.java

@@ -61,12 +61,23 @@ import com.facebook.react.uimanager.events.EventDispatcher;
 
     float width = node.getLayoutWidth();
     float height = node.getLayoutHeight();
-    collectStateForMountableNode(node, tag, width, height);
-
     float left = node.getLayoutX();
     float top = node.getLayoutY();
     float right = left + width;
     float bottom = top + height;
+
+    collectStateForMountableNode(
+        node,
+        tag,
+        left,
+        top,
+        right,
+        bottom,
+        Float.NEGATIVE_INFINITY,
+        Float.NEGATIVE_INFINITY,
+        Float.POSITIVE_INFINITY,
+        Float.POSITIVE_INFINITY);
+
     node.updateNodeRegion(left, top, right, bottom);
 
     mViewsToUpdateBounds.add(node);
@@ -166,8 +177,14 @@ import com.facebook.react.uimanager.events.EventDispatcher;
   private void collectStateForMountableNode(
       FlatShadowNode node,
       int tag,
-      float width,
-      float height) {
+      float left,
+      float top,
+      float right,
+      float bottom,
+      float clipLeft,
+      float clipTop,
+      float clipRight,
+      float clipBottom) {
     mDrawCommands.start(node.getDrawCommands());
     mAttachDetachListeners.start(node.getAttachDetachListeners());
     mNodeRegions.start(node.getNodeRegions());
@@ -181,6 +198,14 @@ import com.facebook.react.uimanager.events.EventDispatcher;
 
       isAndroidView = true;
       needsCustomLayoutForChildren = androidView.needsCustomLayoutForChildren();
+
+      // AndroidView might scroll (e.g. ScrollView) so we need to reset clip bounds here
+      // Otherwise, we might scroll clipped content. If AndroidView doesn't scroll, this is still
+      // harmless, because AndroidView will do its own clipping anyway.
+      clipLeft = Float.NEGATIVE_INFINITY;
+      clipTop = Float.NEGATIVE_INFINITY;
+      clipRight = Float.POSITIVE_INFINITY;
+      clipBottom = Float.POSITIVE_INFINITY;
     } else if (node.isVirtualAnchor()) {
       // If RCTText is mounted to View, virtual children will not receive any touch events
       // because they don't get added to nodeRegions, so nodeRegions will be empty and
@@ -190,7 +215,18 @@ import com.facebook.react.uimanager.events.EventDispatcher;
       addNodeRegion(node.getNodeRegion());
     }
 
-    collectStateRecursively(node, 0, 0, width, height, isAndroidView, needsCustomLayoutForChildren);
+    collectStateRecursively(
+        node,
+        left,
+        top,
+        right,
+        bottom,
+        clipLeft,
+        clipTop,
+        clipRight,
+        clipBottom,
+        isAndroidView,
+        needsCustomLayoutForChildren);
 
     boolean shouldUpdateMountState = false;
     final DrawCommand[] drawCommands = mDrawCommands.finish();
@@ -290,6 +326,10 @@ import com.facebook.react.uimanager.events.EventDispatcher;
       float top,
       float right,
       float bottom,
+      float parentClipLeft,
+      float parentClipTop,
+      float parentClipRight,
+      float parentClipBottom,
       boolean isAndroidView,
       boolean needsCustomLayoutForChildren) {
     if (node.hasNewLayout()) {
@@ -307,7 +347,19 @@ import com.facebook.react.uimanager.events.EventDispatcher;
               Math.round(bottom - top)));
     }
 
-    node.collectState(this, left, top, right, bottom);
+    float clipLeft = Math.max(left, parentClipLeft);
+    float clipTop = Math.max(top, parentClipTop);
+    float clipRight = Math.min(right, parentClipRight);
+    float clipBottom = Math.min(bottom, parentClipBottom);
+
+    node.collectState(this, left, top, right, bottom, clipLeft, clipTop, clipRight, clipBottom);
+
+    if (node.isOverflowVisible()) {
+      clipLeft = parentClipLeft;
+      clipTop = parentClipTop;
+      clipRight = parentClipRight;
+      clipBottom = parentClipBottom;
+    }
 
     for (int i = 0, childCount = node.getChildCount(); i != childCount; ++i) {
       FlatShadowNode child = (FlatShadowNode) node.getChildAt(i);
@@ -316,7 +368,16 @@ import com.facebook.react.uimanager.events.EventDispatcher;
         continue;
       }
 
-      processNodeAndCollectState(child, left, top, isAndroidView, needsCustomLayoutForChildren);
+      processNodeAndCollectState(
+          child,
+          left,
+          top,
+          clipLeft,
+          clipTop,
+          clipRight,
+          clipBottom,
+          isAndroidView,
+          needsCustomLayoutForChildren);
     }
   }
 
@@ -337,6 +398,10 @@ import com.facebook.react.uimanager.events.EventDispatcher;
       FlatShadowNode node,
       float parentLeft,
       float parentTop,
+      float parentClipLeft,
+      float parentClipTop,
+      float parentClipRight,
+      float parentClipBottom,
       boolean parentIsAndroidView,
       boolean needsCustomLayout) {
     int tag = node.getReactTag();
@@ -359,13 +424,34 @@ import com.facebook.react.uimanager.events.EventDispatcher;
         mDrawCommands.add(DrawView.INSTANCE);
       }
 
-      collectStateForMountableNode(node, tag, width, height);
+      collectStateForMountableNode(
+          node,
+          tag,
+          left - left,
+          top - top,
+          right - left,
+          bottom - top,
+          parentClipLeft - left,
+          parentClipTop - top,
+          parentClipRight - left,
+          parentClipBottom - top);
 
       if (!needsCustomLayout) {
         mViewsToUpdateBounds.add(node);
       }
     } else {
-      collectStateRecursively(node, left, top, right, bottom, false, false);
+      collectStateRecursively(
+          node,
+          left,
+          top,
+          right,
+          bottom,
+          parentClipLeft,
+          parentClipTop,
+          parentClipRight,
+          parentClipBottom,
+          false,
+          false);
       addNodeRegion(node.getNodeRegion());
     }
   }