折叠布局下方布局显示不全问题

在折叠布局AppBarLayout下方布局外层需要嵌套

  app:layout_behavior="@string/appbar_scrolling_view_behavior"

这个属性使得下方布局在顶部toolbar下方。但是如果下方的RecyclerView或者其他控件取消联动效果

  recyclerView.setNestedScrollingEnabled(false)

或者因某些其他原因在顶部不折叠的情况下需要显示到最底部布局，换句话说，在顶部toolbar未折叠情况下，下方RecyclerView或者其他布局无法显示到最后一项。
如果想要在未折叠情况下显示到最后一项，需要使用自定义的behavior，代码如下

import android.content.Context;
import android.support.design.widget.AppBarLayout;
import android.support.design.widget.CoordinatorLayout;
import android.util.AttributeSet;
import android.view.View;

/**
 * Created by Administrator on 2016/7/1.
 */
public class FixScrollingFooterBehavior extends AppBarLayout.ScrollingViewBehavior {

    private AppBarLayout appBarLayout;

    public FixScrollingFooterBehavior() {
        super();
    }

    public FixScrollingFooterBehavior(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    public boolean onDependentViewChanged(CoordinatorLayout parent, View child, View dependency) {

        if (appBarLayout == null) {
            appBarLayout = (AppBarLayout) dependency;
        }

        final boolean result = super.onDependentViewChanged(parent, child, dependency);
        final int bottomPadding = calculateBottomPadding(appBarLayout);
        final boolean paddingChanged = bottomPadding != child.getPaddingBottom();
        if (paddingChanged) {
            child.setPadding(
                    child.getPaddingLeft(),
                    child.getPaddingTop(),
                    child.getPaddingRight(),
                    bottomPadding);
            child.requestLayout();
        }
        return paddingChanged || result;
    }

    private int calculateBottomPadding(AppBarLayout dependency) {
        final int totalScrollRange = dependency.getTotalScrollRange();
        return totalScrollRange + dependency.getTop();
    }
}

然后在xml中替换app:layout_behavior="@string/appbar_scrolling_view_behavior"属性为如下

  app:layout_behavior="com.news.detail.FixScrollingFooterBehavior"

就行了...