/**
* Copyright (c) Facebook, Inc. and its affiliates.
*
*
This source code is licensed under the MIT license found in the LICENSE file in the root
* directory of this source tree.
*/
package com.facebook.react.uimanager;
import android.view.View;
import android.view.ViewGroup;
import java.util.List;
import java.util.WeakHashMap;
import javax.annotation.Nullable;
/** Class providing children management API for view managers of classes extending ViewGroup. */
public abstract class ViewGroupManager
extends BaseViewManager implements IViewManagerWithChildren {
private static WeakHashMap mZIndexHash = new WeakHashMap<>();
@Override
public LayoutShadowNode createShadowNodeInstance() {
return new LayoutShadowNode();
}
@Override
public Class extends LayoutShadowNode> getShadowNodeClass() {
return LayoutShadowNode.class;
}
@Override
public void updateExtraData(T root, Object extraData) {}
public void addView(T parent, View child, int index) {
parent.addView(child, index);
}
/**
* Convenience method for batching a set of addView calls Note that this adds the views to the
* beginning of the ViewGroup
*
* @param parent the parent ViewGroup
* @param views the set of views to add
*/
public void addViews(T parent, List views) {
for (int i = 0, size = views.size(); i < size; i++) {
addView(parent, views.get(i), i);
}
}
public static void setViewZIndex(View view, int zIndex) {
mZIndexHash.put(view, zIndex);
}
public static @Nullable Integer getViewZIndex(View view) {
return mZIndexHash.get(view);
}
public int getChildCount(T parent) {
return parent.getChildCount();
}
public View getChildAt(T parent, int index) {
return parent.getChildAt(index);
}
public void removeViewAt(T parent, int index) {
parent.removeViewAt(index);
}
public void removeView(T parent, View view) {
for (int i = 0; i < getChildCount(parent); i++) {
if (getChildAt(parent, i) == view) {
removeViewAt(parent, i);
break;
}
}
}
public void removeAllViews(T parent) {
for (int i = getChildCount(parent) - 1; i >= 0; i--) {
removeViewAt(parent, i);
}
}
/**
* Returns whether this View type needs to handle laying out its own children instead of deferring
* to the standard css-layout algorithm. Returns true for the layout to *not* be automatically
* invoked. Instead onLayout will be invoked as normal and it is the View instance's
* responsibility to properly call layout on its children. Returns false for the default behavior
* of automatically laying out children without going through the ViewGroup's onLayout method. In
* that case, onLayout for this View type must *not* call layout on its children.
*/
@Override
public boolean needsCustomLayoutForChildren() {
return false;
}
/**
* Returns whether or not this View type should promote its grandchildren as Views. This is an
* optimization for Scrollable containers when using Nodes, where instead of having one ViewGroup
* containing a large number of draw commands (and thus being more expensive in the case of an
* invalidate or re-draw), we split them up into several draw commands.
*/
public boolean shouldPromoteGrandchildren() {
return false;
}
}