content: /**
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package org.apache.weex.ui.flat;
  
  
  import android.support.annotation.RestrictTo;
  import android.support.annotation.RestrictTo.Scope;
  import android.util.Pair;
  import android.view.ViewGroup;
  
  import org.apache.weex.WXSDKInstance;
  import org.apache.weex.ui.action.BasicComponentData;
  import org.apache.weex.ui.component.WXComponent;
  import org.apache.weex.ui.component.WXVContainer;
  import org.apache.weex.ui.flat.widget.AndroidViewWidget;
  import org.apache.weex.ui.flat.widget.Widget;
  
  import java.util.LinkedList;
  import java.util.List;
  
  @RestrictTo(Scope.LIBRARY)
  public abstract class WidgetContainer<T extends ViewGroup> extends WXVContainer<T> {
  
    protected List<Widget> widgets;
  
    public WidgetContainer(WXSDKInstance instance, WXVContainer parent, BasicComponentData basicComponentData) {
      super(instance, parent, basicComponentData);
    }
  
    protected abstract void mountFlatGUI();
  
    protected abstract void unmountFlatGUI();
  
    public boolean intendToBeFlatContainer() {
      return false;
    }
  
    @Override
    public void createChildViewAt(int index) {
      if (intendToBeFlatContainer()) {
        Pair<WXComponent, Integer> ret = rearrangeIndexAndGetChild(index);
        if (ret.first != null) {
          WXComponent child = ret.first;
          Widget flatChild;
          FlatGUIContext uiImp = getInstance().getFlatUIContext();
          WidgetContainer parent = uiImp.getFlatComponentAncestor(this);
          if (parent == null || uiImp.getAndroidViewWidget(this) != null) {
            parent = this;
          }
          uiImp.register(child, parent);
  
          if (child instanceof FlatComponent && !((FlatComponent) child).promoteToView(false)) {
            flatChild = ((FlatComponent) child).getOrCreateFlatWidget();
          } else {
            flatChild = new AndroidViewWidget(uiImp);
            uiImp.register(child, (AndroidViewWidget) flatChild);
            child.createView();
            ((AndroidViewWidget) flatChild).setContentView(child.getHostView());
            //TODO Use a sort algorithm to decide the childIndex of AndroidViewWidget
            parent.addSubView(child.getHostView(), -1);
          }
          uiImp.register(flatChild, child);
          addFlatChild(flatChild, ret.second);
        }
      } else {
        super.createChildViewAt(index);
      }
    }
  
    private void addFlatChild(Widget widget, int index) {
      if(widgets == null){
        widgets = new LinkedList<>();
      }
      if (index >= widgets.size()) {
        widgets.add(widget);
      } else {
        widgets.add(index, widget);
      }
      //TODO do a partial update, not mount the whole flatContainer.
      mountFlatGUI();
    }
  }
  