滑动折叠效果简单实现

绿色为标题，滑动时始终不会被折叠、不会滑动。红色和黑色会在滑动的时候折叠，先折叠红色，在折叠黑色。

activity_shop_search.xml：

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">
    <androidx.coordinatorlayout.widget.CoordinatorLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <com.google.android.material.appbar.AppBarLayout
            android:id="@+id/appbar"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:elevation="0dp">

            <com.google.android.material.appbar.CollapsingToolbarLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                app:layout_scrollFlags="scroll|exitUntilCollapsed">
                <LinearLayout
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:orientation="vertical">
                    <ImageView
                        android:layout_width="match_parent"
                        android:layout_height="200dp"
                        android:background="@color/red" />

                    <ImageView
                        android:layout_width="match_parent"
                        android:layout_height="44dp"
                        android:background="@color/black" />
                </LinearLayout>
                <androidx.appcompat.widget.Toolbar
                    app:layout_collapseMode="pin"
                    android:layout_width="match_parent"
                    android:layout_height="44dp"
                    android:background="@color/ugckit_color_green">
                    <TextView
                        android:layout_width="match_parent"
                        android:layout_height="match_parent"
                        android:gravity="center"
                        android:textColor="@color/white"
                        android:text="aaaaaaaaaaaaaaaa" />
                </androidx.appcompat.widget.Toolbar>



            </com.google.android.material.appbar.CollapsingToolbarLayout>

        </com.google.android.material.appbar.AppBarLayout>

    </androidx.coordinatorlayout.widget.CoordinatorLayout>


</layout>

ShopSearchActivity.java：

package com.example.supermarket.activity;

import androidx.lifecycle.ViewModelProvider;
import com.alibaba.android.arouter.facade.annotation.Route;
import com.example.common.util.CCRouterTable;
import com.example.supermarket.R;
import com.example.supermarket.databinding.ActivityShopSearchBinding;
import com.example.supermarket.model.SearchActivityModel;
import com.example.view.base.BaseJavaActivity;

@Route(path = CCRouterTable.SUPERMARKET_SHOP_SEARCH)
public class ShopSearchActivity extends BaseJavaActivity<ActivityShopSearchBinding, SearchActivityModel> {

    @Override
    protected void initListener() {
    }

    @Override
    protected SearchActivityModel initViewModel() {
        return new ViewModelProvider(this, ViewModelProvider.AndroidViewModelFactory.getInstance(getApplication())).get(SearchActivityModel.class);
    }

    @Override
    protected boolean isARouterInject() {
        return false;
    }

    @Override
    protected boolean useEventBus() {
        return false;
    }

    @Override
    public int getLayoutId() {
        return R.layout.activity_shop_search;
    }

    @Override
    public void initData() {
    }
}