recyclerview notifyItemInserted notifyItemRemoved随机行为

Question

我被困了好几个小时。我有一个带有recyclerview的活动。要添加到列表中，用户转到另一个活动，在那里他从一个字符串列表中进行选择。第二个活动将字符串返回给第一个活动，并将字符串添加到recyclerview的末尾。

如果用户点击了Recyclerview中项目的长按，则会出现一个对话框，他可以在该对话框中删除该项目。但是，一旦项目被删除，事情就会非常错误。有时列表会更改，有时当您从第二个活动添加另一个项目时，旧项目会返回。它如此随意，很难准确解释。在日志中，我看到正确的字符串已从第二个活动返回，但回收器视图无法正确显示。怎么回事？

即使列表“搞砸了”，当我重新进入活动时，我也会从列表中调用我的SharedPreferences，这一切都显示正常。所以ArrayList是正确的，只是在删除某些东西后它才能在recyclerview中正确显示。我希望它清楚。

以下是我在活动中的代码：

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_off_limits);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    offLimitsItemsList = new ArrayList<>();

    offLimitsItemsList = SharedPreferencesManager.getOffLimitsItemsList(this);


    getSupportActionBar().setTitle("Off limits (This week)");

    getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    getSupportActionBar().setDisplayShowHomeEnabled(true);


    offLimitsRecyclerView = findViewById(R.id.off_limits_recycler_view);
    offLimitsAdapter = new OffLimitsAdapter(offLimitsItemsList);


    offLimitsAdapter.setOnItemClickListener(new OffLimitsAdapter.ClickListener() {

        @Override
        public void onItemLongClick(final int position, View v) {
            Log.d(TAG, "onItemClick pos = " + position);


            AlertDialog.Builder builder = new AlertDialog.Builder(OffLimitsActivity.this);
            builder.setMessage(R.string.dialog_delete)
                    .setPositiveButton(R.string.yes, new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int id) {

                            Log.d(TAG, offLimitsItemsList.get(position) + " removed");

                            offLimitsItemsList.remove(position);

                            offLimitsAdapter.notifyItemRemoved(position);

                            SharedPreferencesManager.setOffLimitsItemsList(OffLimitsActivity.this, offLimitsItemsList);
                        }
                    })
                    .setNegativeButton(R.string.cancel, new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int id) {
                            // User cancelled the dialog
                        }
                    });
            // Create the AlertDialog object and return it
            builder.create();
            builder.show();

        }

    });


    offLimitsRecyclerView.setAdapter(offLimitsAdapter);
    offLimitsRecyclerView.setLayoutManager(new LinearLayoutManager(this));

}

@Override
public boolean onSupportNavigateUp() {
    onBackPressed();
    return true;
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (resultCode == RESULT_OK){
        Log.d(TAG, "onActivityResult");
        String itemEaten= data.getStringExtra(OFF_LIMITS_ITEM_EATEN);
        offLimitsItemsList.add(itemEaten);
        Log.d(TAG, "Item eaten: " + itemEaten);

        offLimitsAdapter.notifyItemInserted(offLimitsItemsList.size()-1);

        SharedPreferencesManager.setOffLimitsItemsList(OffLimitsActivity.this, offLimitsItemsList);

    }


}


@Override
public boolean onCreateOptionsMenu(Menu menu) {

    getMenuInflater().inflate(R.menu.off_limits_menu_add_item, menu);


    return super.onCreateOptionsMenu(menu);
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case R.id.action_add_off_limits:

            Log.d(TAG, "Add clicked");

            Intent intent = new Intent(OffLimitsActivity.this, SearchOffLimitsItemActivity.class);
            startActivityForResult(intent, SEARCH_OFF_LIMIT_RESULT_CODE);

            return true;
        default:
            return super.onOptionsItemSelected(item);
    }


}

这是适配器：

public class OffLimitsAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {


private static ClickListener clickListener;

public TextView offLimitsTextViewItem;
ArrayList<String> offLimitsItemsList = new ArrayList<>();

public OffLimitsAdapter(ArrayList<String> offLimitsItemsList) {

    this.offLimitsItemsList = offLimitsItemsList;

}


public interface ClickListener {

    void onItemLongClick(int position, View v);
}


class OffLimitsViewHolder extends RecyclerView.ViewHolder implements View.OnLongClickListener{

    public OffLimitsViewHolder(View view) {
        super(view);

        view.setOnLongClickListener(this);

        offLimitsTextViewItem = (TextView)view.findViewById(R.id.off_limits_item_text_view);
    }


    @Override
    public boolean onLongClick(View v) {
        clickListener.onItemLongClick(getAdapterPosition(), v);
        return false;
    }


}

public void setOnItemClickListener(ClickListener clickListener) {
    OffLimitsAdapter.clickListener = clickListener;
}

    @Override
    public int getItemViewType(int position) {
        return position;
    }

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

@Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        View itemView = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.off_limts_item_row, parent, false);




        return new OffLimitsViewHolder(itemView);
    }


    @Override
    public void onBindViewHolder(final RecyclerView.ViewHolder holder, final int position) {


                offLimitsTextViewItem.setText("" + holder.getAdapterPosition() + ". " + offLimitsItemsList.get(position));

        }
    }