public class ReleaseMessageActivity extends AppCompatActivity {

 @BindView(R.id.text_cancel)
 TextView textCancel;
 @BindView(R.id.text_release)
 TextView textRelease;
 @BindView(R.id.mRec)
 RecyclerView mRec;
 @BindView(R.id.et_messsage)
 EditText etMesssage;
 private ArrayList<String> listImagePath;
 private ArrayList<String> mList = new ArrayList<>();
 private ReleaseMsgAdapter adapter;

 private ArrayList<String> list = new ArrayList<String>();

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_release_message);
 ButterKnife.bind(this);
 setRecyclerview();
 }

 private void setRecyclerview() {
 if (mList != null) {
  GridLayoutManager gridLayoutManager = new GridLayoutManager(this, 4);
  mRec.setLayoutManager(gridLayoutManager);
  adapter = new ReleaseMsgAdapter(ReleaseMessageActivity.this, mList);
  mRec.setAdapter(adapter);
 }

 }

 @OnClick({R.id.text_cancel, R.id.text_release})
 public void onClick(View view) {
 switch (view.getId()) {
  case R.id.text_cancel:
  ToastUtil.showToast("取消");
  break;
  case R.id.text_release:
  ToastUtil.showToast("發布");
  break;
 }
 }
 //用戶選中圖片后，拿到回掉結果
 @Override
 protected void onActivityResult(int requestCode, int resultCode, Intent data) {
 super.onActivityResult(requestCode, resultCode, data);
 if (requestCode == 0 && resultCode == RESULT_OK) {
  listImagePath = data.getStringArrayListExtra(EXTRA_RESULT);
  compress(listImagePath);
 }
 }
//壓縮 拿到返回選中圖片的集合url，然后轉換成file文件
 public void compress(ArrayList<String> list) {
 for (String imageUrl : list) {
  LogUtils.e(">>>>>>", imageUrl);
  File file = new File(imageUrl);
  compressImage(file);
 }
 adapter.addMoreItem(list);
 }
//壓縮
 private void compressImage(File file) {
 Luban.get(this)//用的第三方的壓縮，開源庫 Luban 大家可以自行百度
  .load(file)   //傳人要壓縮的圖片
  .putGear(Luban.THIRD_GEAR) //設定壓縮檔次，默認三擋
  .setCompressListener(new OnCompressListener() { //設置回調
   @Override
   public void onStart() {
   //TODO 壓縮開始前調用，可以在方法內啟動 loading UI
   }

   @Override
   public void onSuccess(final File file) {
   URI uri = file.toURI();
   String[] split = uri.toString().split(":");
   list.add(split[1]);//壓縮后返回的文件，帶file字樣，所以需要截取
   LogUtils.e(BaseApplication.TAG, uri + "????????????" + split[1]);
   }

   @Override
   public void onError(Throwable e) {
   //TODO 當壓縮過去出現問題時調用
   }
  }).launch();//啟動壓縮
 }
}

public class ReleaseMsgAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
 private Activity context;
 private ArrayList<String> mList;
 private final LayoutInflater inflater;
 private static final int ITEM_TYPE_ONE = 0x00001;
 private static final int ITEM_TYPE_TWO = 0x00002;
 /**
 *這里之所以用多行視圖，因為我們默認的有一張圖片的（那個帶+的圖片，用戶點擊它才會才會讓你去選擇圖片）
 *集合url為空的時候，默認顯示它，當它達到集合9時，這個圖片會自動隱藏。
 */
 public ReleaseMsgAdapter(Activity context, ArrayList<String> mList) {
 this.context = context;
 this.mList = mList;
 inflater = LayoutInflater.from(context);
 }

 @Override
 public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
 parent.setPadding(20, 0, 20, 0);
 switch (viewType) {
  case ITEM_TYPE_ONE:
  return new MyHolder(inflater.inflate(R.layout.release_message_item, parent, false));
  case ITEM_TYPE_TWO:
  return new MyTWOHolder(inflater.inflate(R.layout.release_message_two_item, parent, false));
  default:
  return null;
 }
 }

 @Override
 public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
 if (holder instanceof MyHolder) {
  bindItemMyHolder((MyHolder) holder, position);
 } else if (holder instanceof MyTWOHolder) {
  bindItemTWOMyHolder((MyTWOHolder) holder, position);
 }
 }

 private void bindItemTWOMyHolder(final MyTWOHolder holder, int position) {
 LogUtils.e("Adapter", listSize() + "");
 if (listSize() >= 9) {//集合長度大于等于9張時，隱藏 圖片
  holder.imageview2.setVisibility(View.GONE);
 }
 holder.imageview2.setOnClickListener(new View.OnClickListener() {
  @Override
  public void onClick(View v) {
  //選擇圖片
  CommonUtil.uploadPictures(context, 9 - listSize(), 0);
  }
 });
 }

 private void bindItemMyHolder(MyHolder holder, int position) {
 Glide.with(context)
  .load(mList.get(position))
  .centerCrop()
  .into(holder.imageview);
 }

 @Override
 public int getItemViewType(int position) {
 if (position + 1 == getItemCount()) {
  return ITEM_TYPE_TWO;
 } else {
  return ITEM_TYPE_ONE;
 }
 }

 @Override
 public int getItemCount() {
 LogUtils.e("getItemCount", mList.size() + 1 + "");
 return mList.size() + 1;
 }

 class MyHolder extends RecyclerView.ViewHolder {
 private final ImageView imageview;
 public MyHolder(View itemView) {
  super(itemView);
  imageview = (ImageView) itemView.findViewById(R.id.imageview);
 }
 }

 class MyTWOHolder extends RecyclerView.ViewHolder {
 private final ImageView imageview2;
 public MyTWOHolder(View itemView) {
  super(itemView);
  imageview2 = (ImageView) itemView.findViewById(R.id.imageview2);
 }
 }
 //對外暴露方法 。點擊添加圖片（類似于上啦加載數據）
 public void addMoreItem(ArrayList<String> loarMoreDatas) {
 mList.addAll(loarMoreDatas);
 notifyDataSetChanged();
 }
//得到集合長度
 public int listSize() {
 int size = mList.size();
 return size;
 }
}

/*
* 選擇圖片
* */
 public static Intent uploadPictures(Activity activity, int number,int requestCode){
 //加載圖片
 PhotoPickerIntent intent = new PhotoPickerIntent(activity);
 intent.setSelectModel(SelectModel.MULTI);//多選
 intent.setShowCarema(true); // 是否顯示拍照
 intent.setMaxTotal(number); // 最多選擇照片數量，默認為9
// intent.setSelectedPaths(imagePaths); // 已選中的照片地址， 用于回顯選中狀態
 intent.putExtra("type","photo");//選擇方式；
 activity.startActivityForResult(intent,requestCode);
 return intent;
 }