RecyclerView update last position with continuous data

Question

first of all when i'll get to my computer i will post code.

I'm trying to add and update the RecyclerViews from Speechrecognition data. For SpeechRecognition i'm using Google Cloud Speech I'm making a "Chat - view" every time the Speech is completed is adding the result to RecyclerView. I want to modify it by adding the new item as the onVoice() is recognized and update it as is recognizing the speech ( the result is still not final)

My approach was: as the SpeechRecognition is triggered by voice the new item is added (onVoiceStart) as the recognizers onVoice callback is triggered (new speech data chunk is recognized) i will delete the RecyclerViews last item and add the "chunk" to last position and after that calling adapter.notifyItemChanged(speechResults.size()-1)

Answer 1

Solution I :

     // Step 1: find the holder 
 RecyclerView.ViewHolder holder = recyclerView.findViewHolderForAdapterPosition(speechResults.size() - 1);

     //   Step 2: Check if the holder is not null and if has itemView .
    if (holder != null) {

        if (holder.itemView != null) {
            // from itemview find the TextView  and set the desired text :
            if (holder.getAdapterPosition() == speechResults.size() - 1) {
                ((TextView) holder.itemView.findViewById(R.id.speech_sent_textView))
                        .setText(text);
            }
        }
 // Now update the adapter item also but do not notify the adapter change.

Solution II : Using library LastAdapter

1. Add Dependecy -> follow this

2. in the Layout add new the root tag "< layout"

               //Delte the space after "<"
     < layout xmlns:android="http://schemas.android.com/apk/res/android">
   
   <data>
       <variable name="item" type="com.github.nitrico.lastadapterproject.item.Header"/>
   </data>
   
   <TextView
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
   
       // you use  like thius "@{youritem.speecSent"
       android:text="@{item.text}"/>
       //Delte the space after "< "
    < /layout>
   

   NOTE: for using multiple layouts the data tag must have same variable name.

      <data>   
          // this name has to be same in every xml layout types.
       <variable name="item" type="com.github.nitrico.lastadapterproject.item.Header"/>
       </data>
   

3. Java part: NOTE : listOfItems must be Observable ArrayList

     speechResults = new ObservableArrayList<>();
        ...
       new LastAdapter(speechResults , BR.item)
      .map(SpeechResult.class, R.layout.speech_sent)
      .map(SpeechResult.class, R.layout.speech_received)
      .into(recyclerView);
   

BR.item - > you have to enable the databinding in build Gradle. the .item - > is the name given in the layout for data (that has to be same)

if you want to handle the LayoutType using the same Item type (Class)

            new LastAdapter(speechResults, BR.item )
            .map(SpeechResult.class, R.layout.speech_sent_content)
            .map(SpeechResult.class, R.layout.speech_received_content)
              .handler(new TypeHandler() {
                  @Nullable
                  @Override
                  public BaseType getItemType(Object o, int i) {
                      if(((SpeechResult) o).getSpeechType()==SpeechResult.SPEECH_TYPE_SENT){
                          return new BaseType(R.layout.speech_sent_content);
                      }
                      return new BaseType(R.layout.speech_received_content);
                  }
              })

            .into(recyclerView);

to adding new items in the recyclerView simply add item to your itemlist. LastAdapter will handle the refresh of data.