在安卓中实现CoordinatorLayout+AppBarLayout+TabLayout+RecycleView 悬停效果 滑动rv列表tablayout定位效果

效果图

在开发中要用到 写个demo 记录一下，有这个需求的同志也可以做个参考

Xml

<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    >

    <android.support.design.widget.CoordinatorLayout
        android:id="@+id/map"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        tools:context=".MainActivity">

        <android.support.design.widget.AppBarLayout
            android:id="@+id/app_bar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
            <TextView
                android:layout_width="match_parent"
                android:layout_height="50dp"
                android:gravity="center"
                android:text="哈哈哈哈哈"
                app:layout_scrollFlags="scroll"
                />
            <ImageView
                android:id="@+id/iv_tag"
                android:layout_width="match_parent"
                android:layout_height="200dp"
                android:background="?attr/colorPrimary"
                android:scaleType="fitXY"
                app:layout_collapseMode="parallax"
                android:src="@drawable/ic_launcher_background"
                app:layout_scrollFlags="scroll|exitUntilCollapsed" />

            <android.support.design.widget.TabLayout
                android:id="@+id/main_tab"
                android:layout_width="match_parent"
                android:layout_height="50dp"
                android:visibility="gone"
                />
            <TextView
                android:id="@+id/tv_test"
                android:layout_width="match_parent"
                android:layout_height="50dp"
                android:text="哈哈哈哈哈"
                android:visibility="visible"
                />

        </android.support.design.widget.AppBarLayout>


        <android.support.v7.widget.RecyclerView
            android:id="@+id/mian_recy"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:layout_behavior="@string/appbar_scrolling_view_behavior"
           />


    </android.support.design.widget.CoordinatorLayout>


</FrameLayout>

View

 private List<MainBean> list;
    private MainAdapter adapter;
    private RecyclerView recyclerView;

    private LinearLayoutManager manager;
    private TabLayout tabLayout;
    /**
     *关于bug问题，可以在adapter 中给最后一个item 填充一个空视图把整个布局顶上去完成滑动
     *demo中就给到一个思路了
    **/
    
    private  int pos=0;
    private TextView tv_test;
    private AppBarLayout appBarLayout;
    private String[] str = {"测试1", "测试2", "测试3", "测试4", "测试5", "测试6", "测试7", "测试8", "测试9", "测试10"};
    private ImageView iv_tag;
    private int[] str1 = {0, 11, 22, 33, 44, 55, 66, 77, 88, 99};
    private boolean isScrolled = false;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initData();
        init();
        initTab();
        //因为需求原因这里先放置点击收缩appbar的占位视图
        tv_test.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (pos<250){//这里可以根据实际情况来做出appbar的收缩判断 高度可以通过自己计算
                    appBarLayout.setExpanded(false);
                }
            }
        });



    }

    private void initTab() {
        for (int i = 0; i < str.length; i++) {
            tabLayout.addTab(tabLayout.newTab().setText(str[i]));
        }
        //标签页可以滑动
        tabLayout.setTabMode(TabLayout.MODE_SCROLLABLE);
        tabLayout.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
            @Override
            public void onTabSelected(TabLayout.Tab tab) {
                int pos = tab.getPosition();
                if (!isScrolled) {
                    manager.scrollToPositionWithOffset(str1[pos], 0);
                }
            }

            @Override
            public void onTabUnselected(TabLayout.Tab tab) {

            }

            @Override
            public void onTabReselected(TabLayout.Tab tab) {

            }
        });

    }

    private void init() {
        recyclerView = findViewById(R.id.mian_recy);
        tabLayout = findViewById(R.id.main_tab);
        appBarLayout=findViewById(R.id.app_bar);
        tv_test=findViewById(R.id.tv_test);
        iv_tag=findViewById(R.id.iv_tag);
        manager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(manager);
        adapter = new MainAdapter(list);
        recyclerView.setAdapter(adapter);
        adapter.setOnItemClickListener(new BaseQuickAdapter.OnItemClickListener() {
            @Override
            public void onItemClick(BaseQuickAdapter adapter, View view, int position) {
                //处理自己的事件
                Toast.makeText(MainActivity.this, "点击的item=" + position, Toast.LENGTH_SHORT).show();
            }
        });


        recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(@NonNull RecyclerView recyclerView, int newState) {
                super.onScrollStateChanged(recyclerView, newState);
                //重写该方法主要是判断recyclerview是否在滑动
                //0停止 ，12都是滑动

                if (newState == 0) {
                    isScrolled = false;
                } else {
                    isScrolled = true;
                }
                setMsg("isScrolled" + isScrolled + "--newState=" + newState);
            }

            @Override
            public void onScrolled(@NonNull RecyclerView recyclerView, int dx, int dy) {
                super.onScrolled(recyclerView, dx, dy);
                /**
                 * 关于滑动rv 定位tab的实现逻辑  可根据自己的项目需要进行修改
                 * **/
                if (isScrolled) {
                    int top = manager.findFirstVisibleItemPosition();
                    int bottom = manager.findLastVisibleItemPosition();

                    int pos = 0;
                    if (bottom == list.size() - 1) {
                        //先判断滑到底部，tab定位到最后一个
                        pos = str1.length - 1;
                    } else if (top == str1[str1.length - 1]) {
                        //如果top等于指定的位置，对应到tab即可，
                        pos = str1[str1.length - 1];
                    } else {
                        //循环遍历，需要比较i+1的位置，所以循环长度要减1，
                        //  如果 i<top<i+1,  那么tab应该定位到i位置的字符，不管是向上还是向下滑动
                        for (int i = 0; i < str1.length - 1; i++) {
                            if (top == str1[i]) {
                                pos = i;
                                break;
                            } else if (top > str1[i] && top < str1[i + 1]) {
                                pos = i;
                                break;
                            }
                        }
                    }

                    //设置tab滑动到第pos个
                    tabLayout.setScrollPosition(pos, 0f, true);
                }

            }
        });

        appBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
            @Override
            public void onOffsetChanged(AppBarLayout appBarLayout, int i) {
                Log.e(MainActivity.class.getSimpleName(), "onOffsetChanged: "+i);
                if (Math.abs(i)==iv_tag.getBottom()){
                    pos=Math.abs(i);
                    tv_test.setVisibility(View.GONE);
                    tabLayout.setVisibility(View.VISIBLE);
                }else {
                    pos=0;
                    tabLayout.setVisibility(View.GONE);
                    tv_test.setVisibility(View.VISIBLE);
                }
            }
        });


    }

    public static void setMsg(String str) {
        Log.i("tab", str);
    }

    private void initData() {
        list = new ArrayList<>();
        for (int i = 0; i < 100; i++) {
            list.add(new MainBean("title--" + i));
        }

    }
}

思路就是这些了，也非常的简单。

附上码云链接