android最基本-自定义回调

仅以此篇记录最最基本的接口回调的处理，常见的使用是:recyclerview的条目点击事件...

以recylerview的条目点击事件为例，步骤：
1.在Adapter中定义MyOnItemClickListener接口, 在接口中定义抽象方法

 public interface MyOnItemClickListener{
        void onItemClick(int position);
    }

2. 声明成员变量private MyOnItemClickListener mMyOnItemClickListener;
3. 提供set方法,将别人传入的监听器保存为成员变量 this.mOnBtnClickListener = onBtnClickListener;

   public void setMyOnItemClickListener(MyOnItemClickListener myOnItemClickListener){
        this.mMyOnItemClickListener = myOnItemClickListener;
    }

4. 在onBindViewHolder中调用Listener.onItemClick()方法

 public void onBindViewHolder(MyViewHolder holder, final int position) {
        int resId = resIdList.get(position);
        holder.mImageView.setImageResource(resId);
        holder.itemView.setOnClickListener(new View.OnClickListener() {  给整个条目绑定点击事件
            @Override
            public void onClick(View v) {
                if (mMyOnItemClickListener!=null){
                    mMyOnItemClickListener.onItemClick(position);
                }
            }
        });

    }

5. 在adapter外部即可调用这个接口回调即可

    recyclerAdapter1.setMyOnItemClickListener(new RecyclerAdapter.MyOnItemClickListener(){
                    public void onItemClick(int position){
                        Toast.makeText(RecyclerViewActivity.this, "点击了："+position, Toast.LENGTH_SHORT).show();
                    }
                });