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安卓recyclerview的基本使用

配置 ide adpter .com ner man throw pub divider

1.先在布局文件中寫

 <android.support.v7.widget.RecyclerView
        android:id="@+id/my_recycler_view"
        android:scrollbars="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

2.mainactivity

public class MainActivity extends AppCompatActivity {
    
private RecyclerView mRecyclerView; private ArrayList<String> mDatas=new ArrayList<>(); private MyAdapter myAdapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mRecyclerView
= findViewById(R.id.my_recycler_view); initDatas(); myAdapter =new MyAdapter(mDatas); mRecyclerView.setAdapter(myAdapter); mRecyclerView.setLayoutManager(new LinearLayoutManager(this)); //mRecyclerView.setLayoutManager(new GridLayoutManager(this,4)); // mRecyclerView.setLayoutManager(new StaggeredGridLayoutManager(4,StaggeredGridLayoutManager.HORIZONTAL));
//配置分割線 mRecyclerView.addItemDecoration(new DividerItemDecoration(this,DividerItemDecoration.VERTICAL_LIST)); //事件監聽 myAdapter.setOnItemClickListener(new MyAdapter.OnItemClickListener() { @Override public void onClick(View v, int position, String city) { Toast.makeText(MainActivity.this,city,Toast.LENGTH_SHORT).show(); } }); int size =mDatas.size(); //添加數據到頭部 myAdapter.addData(size,"adddddddddd"); //刪除數據 myAdapter.removeData(0); } private static final String TAG = "MainActivity"; private void initDatas(){ mDatas.add("aa"); mDatas.add("cv"); mDatas.add("cv1"); mDatas.add("cv112"); mDatas.add("cv112"); mDatas.add("cv112"); mDatas.add("cv112"); mDatas.add("cv112"); mDatas.add("cv112"); mDatas.add("cv112"); mDatas.add("cv112"); mDatas.add("cv112"); mDatas.add("cv112"); mDatas.add("cv112"); } }

3.adpter

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
    private static List<String> mData;
    private static OnItemClickListener mListener;
    public void setOnItemClickListener (OnItemClickListener listener){
        mListener=listener;
    }


    public MyAdapter(List<String> data) {
        mData = data;
    }



    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        // 實例化展示的view
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.view_rv_item, parent, false);
        // 實例化viewholder
        ViewHolder viewHolder = new ViewHolder(v);
        return viewHolder;
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        // 綁定數據
        holder.mTv.setText(mData.get(position));
    }

    @Override
    public int getItemCount() {
        return mData == null ? 0 : mData.size();
    }

    public static class ViewHolder extends RecyclerView.ViewHolder {

        TextView mTv;

        public ViewHolder(View itemView) {
            super(itemView);
            mTv = (TextView) itemView.findViewById(R.id.item_tv);

            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    if(mListener!=null){
                        mListener.onClick(view,getLayoutPosition(),mData.get(getLayoutPosition()));
                    }
                }
            });
        }
    }


    interface OnItemClickListener{
        void onClick(View v,int position,String city);

    }


    /*
    *  @param 添加的位置
    *  @param 添加的數據
    * */
    public void addData(int position,String city){
        mData.add(position,city);
        notifyItemInserted(position);
    }


    public void removeData(int position){
        mData.remove(position);
        notifyItemRemoved(position);
    }
}

單獨創建item的布局,view_rv_item.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="45dp">

    <TextView
        android:id="@+id/item_tv"
        android:gravity="center"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        />
</LinearLayout>

item的下劃線,要自己寫一個類,有點麻煩,直接抄了網上

public class DividerItemDecoration extends RecyclerView.ItemDecoration {

    private static final int[] ATTRS = new int[]{
            android.R.attr.listDivider
    };

    public static final int HORIZONTAL_LIST = LinearLayoutManager.HORIZONTAL;

    public static final int VERTICAL_LIST = LinearLayoutManager.VERTICAL;

    private Drawable mDivider;

    private int mOrientation;

    public DividerItemDecoration(Context context, int orientation) {
        final TypedArray a = context.obtainStyledAttributes(ATTRS);
        mDivider = a.getDrawable(0);
        a.recycle();
        setOrientation(orientation);
    }

    public void setOrientation(int orientation) {
        if (orientation != HORIZONTAL_LIST && orientation != VERTICAL_LIST) {
            throw new IllegalArgumentException("invalid orientation");
        }
        mOrientation = orientation;
    }

    @Override
    public void onDraw(Canvas c, RecyclerView parent) {
//        Log.v("recyclerview - itemdecoration", "onDraw()");

        if (mOrientation == VERTICAL_LIST) {
            drawVertical(c, parent);
        } else {
            drawHorizontal(c, parent);
        }

    }

    public void drawVertical(Canvas c, RecyclerView parent) {
        final int left = parent.getPaddingLeft();
        final int right = parent.getWidth() - parent.getPaddingRight();

        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = parent.getChildAt(i);
            android.support.v7.widget.RecyclerView v = new android.support.v7.widget.RecyclerView(parent.getContext());
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child
                    .getLayoutParams();
            final int top = child.getBottom() + params.bottomMargin;
            final int bottom = top + mDivider.getIntrinsicHeight();
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }

    public void drawHorizontal(Canvas c, RecyclerView parent) {
        final int top = parent.getPaddingTop();
        final int bottom = parent.getHeight() - parent.getPaddingBottom();

        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = parent.getChildAt(i);
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child
                    .getLayoutParams();
            final int left = child.getRight() + params.rightMargin;
            final int right = left + mDivider.getIntrinsicHeight();
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }

    @Override
    public void getItemOffsets(Rect outRect, int itemPosition, RecyclerView parent) {
        if (mOrientation == VERTICAL_LIST) {
            outRect.set(0, 0, 0, mDivider.getIntrinsicHeight());
        } else {
            outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0);
        }
    }
}

對了,使用之前要配置先的

   api com.android.support:recyclerview-v7:26.1.0

這裏寫了展示和點擊事件,比較簡單,

安卓recyclerview的基本使用