Android RecyclerView的使用（四）——点击事件

淡淡的烟草味﹌ 2022-06-03 04:07 676阅读 0赞

## Android RecyclerView的使用（四）——点击事件 ##

**前言：** RecyclerView提供了一种插拔式的体验，高度的解耦，异常的灵活，通过设置它提供的不同LayoutManager，ItemDecoration , ItemAnimator实现绚丽的效果。

*  通过布局管理器LayoutManager，可以控制其显示的方式；
 *  通过ItemDecoration，可以控制Item间的间隔（可定制）；
 *  通过ItemAnimator，可以控制Item增删的动画；
 *  至于点击、长按事件，RecyclerView并没有给我们提供相应的方法接口，需要我们自己实现。

上一节我们了解了如何通过RecyclerView 实现瀑布流，本节我们将学习如何为我们的Item添加点击事件。

**效果图：**

![这里写图片描述][SouthEast]

**1、布局文件**

<?xml version="1.0" encoding="utf-8"?>
    <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
    
        <android.support.v7.widget.RecyclerView
            android:id="@+id/recyclerView"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>
    
    </android.support.constraint.ConstraintLayout>

**2、定义item的样式**

<?xml version="1.0" encoding="utf-8"?>
    <LinearLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:background="@drawable/item_bg"
        android:layout_margin="3dp"
        android:layout_height="72dp">
    
        <ImageView
            android:id="@+id/imageView"
            android:layout_margin="20dp"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />
    
        <TextView
            android:id="@+id/textView"
            android:layout_gravity="center_vertical"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />
    
    </LinearLayout>

**3、自定义的Adapter适配器，添加item click接口，设置item的点击事件。**

public class MyAdapter extends RecyclerView.Adapter<MyViewHolder> {
    
        private LayoutInflater mInflater;
        private Context mContext;
        private List<String> mDatas;
        private int[] imgIds;
    
        private OnItemClickListener mOnItemClickListener;
    
        public MyAdapter(Context context, List<String> datas, int[] imgIds) {
            this.mContext = context;
            this.mDatas = datas;
            this.imgIds = imgIds;
            mInflater = LayoutInflater.from(context);
        }
    
        @Override
        public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            View view = mInflater.inflate(R.layout.item_single_textview, parent, false);
            MyViewHolder viewHolder = new MyViewHolder(view);
            return viewHolder;
        }
    
        @Override
        public void onBindViewHolder(final MyViewHolder holder, final int position) {
            holder.textView.setText(mDatas.get(position));
            holder.imageView.setBackgroundResource(imgIds[ position % imgIds.length]);
    
            // item click
            if (mOnItemClickListener != null) {
                holder.itemView.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View view) {
                        mOnItemClickListener.onItemClick(holder.itemView, position);
                    }
                });
            }
    
            // item long click
            holder.itemView.setOnLongClickListener(new View.OnLongClickListener() {
                @Override
                public boolean onLongClick(View view) {
                    mOnItemClickListener.onItemLongClick(holder.itemView, position);
                    return true;
                }
            });
        }
    
        @Override
        public int getItemCount() {
            return mDatas.size();
        }
    
        public void setOnItemClickListener(OnItemClickListener listener) {
            this.mOnItemClickListener = listener;
        }
    
        public void addData(int pos) {
            mDatas.add(pos, "Add one");
            notifyItemInserted(pos);
        }
    
        public void deleteData(int pos) {
            mDatas.remove(pos);
            notifyItemRemoved(pos);
        }
    
        public interface OnItemClickListener {
            void onItemClick(View view, int position);
            void onItemLongClick(View view, int position);
        }
    }
    class MyViewHolder extends RecyclerView.ViewHolder {
    
        ImageView imageView;
        TextView textView;
    
        public MyViewHolder(View itemView) {
            super(itemView);
            textView = itemView.findViewById(R.id.textView);
            imageView = itemView.findViewById(R.id.imageView);
        }
    }

**4、MainActivity.java**

public class MainActivity extends AppCompatActivity {
    
        private RecyclerView recyclerView;
    
        private List<String> mDatas;
        private int[] imgIds;
        private MyAdapter mAdapter;
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
    
            initDatas();
    
            recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
    
            mAdapter = new MyAdapter(this, mDatas, imgIds);
            recyclerView.setAdapter(mAdapter);
    
            //设置RecyclerView的布局管理
            LinearLayoutManager manager = new LinearLayoutManager(this,
                    LinearLayoutManager.VERTICAL, false);
            recyclerView.setLayoutManager(manager);
    
            recyclerView.setItemAnimator(new DefaultItemAnimator());
    
            mAdapter.setOnItemClickListener(new MyAdapter.OnItemClickListener() {
                @Override
                public void onItemClick(View view, int position) {
                    Toast.makeText(MainActivity.this, "clicked " + position,
                            Toast.LENGTH_SHORT).show();
                }
    
                @Override
                public void onItemLongClick(View view, int position) {
                    Toast.makeText(MainActivity.this, "long clicked " + position,
                            Toast.LENGTH_SHORT).show();
                }
            });
        }
    
        @Override
        public boolean onCreateOptionsMenu(Menu menu) {
            getMenuInflater().inflate(R.menu.menu, menu);
            return true;
        }
    
        @Override
        public boolean onOptionsItemSelected(MenuItem item) {
            switch (item.getItemId()) {
                case R.id.add:
                    mAdapter.addData(1);
                    break;
                case R.id.delete:
                    mAdapter.deleteData(1);
                    break;
                case R.id.listView:
                    recyclerView.setLayoutManager(new LinearLayoutManager(MainActivity.this));
                    break;
                case R.id.gridView:
                    recyclerView.setLayoutManager(new GridLayoutManager(MainActivity.this, 2));
                    break;
                case R.id.gridView_hor:
                    recyclerView.setLayoutManager(new StaggeredGridLayoutManager(5,
                            StaggeredGridLayoutManager.HORIZONTAL));
                    break;
                case R.id.staggered:
                    Intent intent = new Intent(this, StaggeredActivity.class);
                    startActivity(intent);
                    break;
                default:
                    break;
            }
            return super.onOptionsItemSelected(item);
        }
    
        private void initDatas() {
            imgIds = new int[]{R.mipmap.pic01, R.mipmap.pic02, R.mipmap.pic03, R.mipmap.pic04,
                    R.mipmap.pic05, R.mipmap.pic06, R.mipmap.pic07};
            mDatas = new ArrayList<>();
            mDatas.add("亳州"); 
            mDatas.add("大娃");
            mDatas.add("二娃");
            mDatas.add("三娃");
            mDatas.add("四娃");
            mDatas.add("五娃");
            mDatas.add("六娃");
            mDatas.add("七娃");
            mDatas.add("喜羊羊");
            mDatas.add("美羊羊");
            mDatas.add("懒羊羊");
            mDatas.add("沸羊羊");
            mDatas.add("暖羊羊");
            mDatas.add("慢羊羊");
            mDatas.add("灰太狼");
            mDatas.add("红太狼");
            mDatas.add("孙悟空");
            mDatas.add("黑猫警长");
            mDatas.add("舒克");
            mDatas.add("贝塔");
            mDatas.add("海尔");
            mDatas.add("阿凡提");
            mDatas.add("邋遢大王");
            mDatas.add("哪吒");
            mDatas.add("没头脑");
            mDatas.add("不高兴");
            mDatas.add("蓝皮鼠");
            mDatas.add("大脸猫");
            mDatas.add("大头儿子");
            mDatas.add("小头爸爸");
            mDatas.add("蓝猫");
            mDatas.add("淘气");
            mDatas.add("叶峰");
            mDatas.add("楚天歌");
            mDatas.add("江流儿");
            mDatas.add("Tom");
            mDatas.add("Jerry");
            mDatas.add("12345");
            mDatas.add("54321");
            mDatas.add("_(:з」∠)_");
            mDatas.add("……%￥#￥%#");
        }
    }

[SouthEast]: /images/20220603/ddeb171a9fb44608b5ff07c55cd2acb4.png