RecycleView的学习使用

RecyclerView出来很长时间了，一直没有去尝试学习，想想很是忏愧！今天整理了一点关于RecyclerView的简单使用方法，算作学习笔记了。

RecyclerView的使用，有三个是必须的Adapter,ViewHolder,LayoutManager,而ItemDecoration和ItemAnimator是可选的。

以下是简单的代码示例：
首先是VIewHoder的：

class TestRecycleHolder extends RecyclerView.ViewHolder{
        protected TextView textView;
        public TestRecycleHolder(View itemView) {
            super(itemView);
            textView= (TextView)   itemView.findViewById(R.id.item_text);

        }

    }

该类必需继承extends RecyclerView.ViewHolder。
适配器Adapter部分：

 class RecycleAdapter extends RecyclerView.Adapter<TestRecycleHolder>
    {

        @Override
        public long getItemId(int position) {
            return super.getItemId(position);
        }


        @Override
        public TestRecycleHolder onCreateViewHolder(ViewGroup parent, int viewType)
        {
            View view= LayoutInflater.from(context).inflate(R.layout.item_view,null);
            return new TestRecycleHolder(view);
        }

        @Override
        public void onBindViewHolder(TestRecycleHolder holder, int position)
        {
           final String name=dataArrayList.get(position);
            holder.textView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Toast.makeText(context, "You clickd TextView at index of "+name,
                                            Toast.LENGTH_SHORT).show();
                }
            });
            holder.textView.setText(name);
        }

        @Override
        public int getItemCount()
        {
            return dataArrayList.size();
        }


    }

该类必需继承RecyclerView.Adapter类。
至于LayoutManager,可以使用系统提供的LinearLayoutManager类，代码如下：

LinearLayoutManager layoutManager = new LinearLayoutManager(this,
                            LinearLayout.VERTICAL, false);
        recyclerView.setLayoutManager(layoutManager);

也可以自己继承RecyclerView.LayoutManager的类，实现该类

   class MyDefineLayoutManager extends RecyclerView.LayoutManager {
        private final MyDefineLayoutManager myff=this;

        @Override
        public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state)
        {
            super.onLayoutChildren(recycler, state);

            if (state.isPreLayout())
            {
                return;
            }
            if (getItemCount() == 0)
                return;

        }

        @Override
        public RecyclerView.LayoutParams generateDefaultLayoutParams()
        {
            return new RecyclerView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,
                ViewGroup.LayoutParams.MATCH_PARENT);
        }
    }

如果想知道如何写自己的LayoutManager，请参阅http://wiresareobsolete.com/2014/09/building-a-recyclerview-layoutmanager-part-1/文章

ItemDecoration，是对Item进行装饰的，比如给Item加个边距等。比如，下面的代码仅仅加了个上边距：

    class SpacesItemDecoration extends RecyclerView.ItemDecoration{
        public SpacesItemDecoration() {
            super();
        }

        @Override
        public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
            super.onDraw(c, parent, state);
        }

        @Override
        public void onDrawOver(Canvas c, RecyclerView parent, RecyclerView.State state) {
            super.onDrawOver(c, parent, state);
        }

        @Override
        public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
            super.getItemOffsets(outRect, view, parent, state);
            outRect.top=10;
        }
    }

文章写得比较粗糙，仅做为一个笔记参考。敬请见谅
参考文献：http://www.tuicool.com/articles/URvIB32
https://www.javacodegeeks.com/2014/11/a-guide-to-android-recyclerview-and-cardview.html
http://www.cnblogs.com/littlepanpc/p/3859983.html
https://github.com/vilyever/HowToCustomLayoutManager
http://www.jianshu.com/p/de31cce8e62f
http://wiresareobsolete.com/2014/09/building-a-recyclerview-layoutmanager-part-1/

http://blog.csdn.net/wyyl1/article/details/48112141