android - make - Cómo resaltar el elemento seleccionado en RecyclerView

recyclerview android studio

Question

He usado RecyclerView para mostrar miniaturas en mi aplicación de edición de imágenes. Cada elemento se compone de una vista de imagen (miniatura) y una vista de texto. En mi aplicación, quiero resaltar solo la miniatura seleccionada actualmente al hacer clic. Ir a través de todas las publicaciones relacionadas en SO pero no pudo encontrar una mejor solución.

Mi clase de adaptador

 public class FiltersAdapter extends RecyclerView.Adapter<FiltersAdapter.ViewHolder> {
private Context mContext;
private List<Type> mDataSet;
private Uri selectedPhoto;
public enum Type {
Original,
Grayscale,
Sepia,
Contrast,
Invert,
Pixel,
Sketch,
Swirl,
Brightness,
Vignette
}
public FiltersAdapter(Context context, List<Type> dataSet, Uri selectedPhoto) {
mContext = context;
mDataSet = dataSet;
this.selectedPhoto = selectedPhoto;
}
@Override
public FiltersAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(mContext).inflate(R.layout.list_item_layout, parent, false);
return new ViewHolder(v);
}
@Override
public void onBindViewHolder(FiltersAdapter.ViewHolder holder, int position) {
switch (mDataSet.get(position)) {
case Original:
holder.image.setImageResource(R.drawable.no_filter);
break;
case Grayscale:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new GrayscaleTransformation())
.into(holder.image);
break;
case Sepia:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new SepiaFilterTransformation(mContext))
.into(holder.image);
break;
case Contrast:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new ContrastFilterTransformation(mContext, 2.0f))
.into(holder.image);
break;
case Invert:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new InvertFilterTransformation(mContext))
.into(holder.image);
break;
case Pixel:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new PixelationFilterTransformation(mContext, 20))
.into(holder.image);
break;
case Sketch:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new SketchFilterTransformation(mContext))
.into(holder.image);
break;
case Swirl:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new SwirlFilterTransformation(mContext, 0.5f, 1.0f, new PointF(0.5f, 0.5f)))
.into(holder.image);
break;
case Brightness:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new BrightnessFilterTransformation(mContext, 0.5f))
.into(holder.image);
break;
case Vignette:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new VignetteFilterTransformation(mContext, new PointF(0.5f, 0.5f),
new float[]{0.0f, 0.0f, 0.0f}, 0f, 0.75f))
.into(holder.image);
break;
default:
holder.image.setImageResource(R.drawable.no_filter);
break;
}
holder.title.setText(mDataSet.get(position).name());
}
@Override
public void onViewAttachedToWindow(ViewHolder holder) {
super.onViewAttachedToWindow(holder);
}
@Override
public int getItemCount() {
return mDataSet.size();
}
@Override
public int getItemViewType(int position) {
return position;
}
static class ViewHolder extends RecyclerView.ViewHolder {
public ImageView image;
public TextView title;
ViewHolder(View itemView) {
super(itemView);
image = (ImageView) itemView.findViewById(R.id.thumbnailImage);
title = (TextView) itemView.findViewById(R.id.title);
}
}
}

Código de fragmento

horizontalFilters = (RecyclerView) mView.findViewById(R.id.rvHorizontal);
LinearLayoutManager horizontalLayoutManagaer
= new LinearLayoutManager(getContext(), LinearLayoutManager.HORIZONTAL, false);
horizontalFilters.setLayoutManager(horizontalLayoutManagaer);
List<Type> dataSet = new ArrayList<>();
dataSet.add(Type.Original);
dataSet.add(Type.Grayscale);
dataSet.add(Type.Sepia);
dataSet.add(Type.Contrast);
dataSet.add(Type.Invert);
dataSet.add(Type.Pixel);
dataSet.add(Type.Sketch);
dataSet.add(Type.Swirl);
dataSet.add(Type.Brightness);
dataSet.add(Type.Vignette);
horizontalFilters.setAdapter(new FiltersAdapter(act, dataSet, selectedPhotoUri));
horizontalFilters.addOnItemTouchListener(new RecyclerClick(act, horizontalFilters, new RecyclerClickListener() {
@Override
public void onClick(View view, int position) {
switch (position){
case 0:
photo.setImageDrawable(drawable);
break;
case 1:
Picasso.with(act)
.load(selectedPhotoUri)
.transform(new GrayscaleTransformation())
.into(photo);
break;
case 2:
Picasso.with(act)
.load(selectedPhotoUri)
.transform(new SepiaFilterTransformation(act))
.into(photo);
break;
case 3:
Picasso.with(act)
.load(selectedPhotoUri)
.transform(new ContrastFilterTransformation(act, 2.0f))
.into(photo);
break;
case 4:
Picasso.with(act)
.load(selectedPhotoUri)
.transform(new InvertFilterTransformation(act))
.into(photo);
break;
case 5:
Picasso.with(act)
.load(selectedPhotoUri)
.transform(new PixelationFilterTransformation(act, 20))
.into(photo);
break;
case 6:
Picasso.with(act)
.load(selectedPhotoUri)
.transform(new SketchFilterTransformation(act))
.into(photo);
break;
case 7:
Picasso.with(act)
.load(selectedPhotoUri)
.transform(new SwirlFilterTransformation(act, 0.5f, 1.0f, new PointF(0.5f, 0.5f)))
.into(photo);
break;
case 8:
Picasso.with(act)
.load(selectedPhotoUri)
.transform(new BrightnessFilterTransformation(act, 0.5f))
.into(photo);
break;
case 9:
Picasso.with(act)
.load(selectedPhotoUri)
.transform(new VignetteFilterTransformation(act, new PointF(0.5f, 0.5f),
new float[]{0.0f, 0.0f, 0.0f}, 0f, 0.75f))
.into(photo);
break;
default:
photo.setImageDrawable(drawable);
break;
}
}
@Override
public void onLongClick(View view, int position) {
}
}));
}

Answer 1

Use el selector de fondo y configúrelo en Android: propiedad de fondo en el diseño xml para el elemento recyclerview

background_selector.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="false" android:state_selected="true">
<shape>
<solid android:color="@color/lightPrimaryColor" />
</shape>
</item>
<item android:state_selected="false">
<shape>
<solid android:color="@android:color/transparent" />
</shape>
</item>
</selector>

recyclerview_item.xml (background_selector se establece en android: propiedad de fondo)

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@drawable/background_selector"
android:orientation="vertical"
android:paddingBottom="8dp"
android:paddingLeft="16dp"
android:paddingRight="16dp"
android:paddingTop="8dp">

Y luego, en el lugar donde obtienes el evento click, puedes establecerlo como seleccionado con la función Ver

view.setSelected (true)

Tendría que implementar la lógica para cuando desea deseleccionar / seleccionar el elemento almacenando la posición de los elementos seleccionados

Answer 2

actualiza tu enumeración a la clase primero para la bandera

public class Type {
public int type; // 0-Original,1-Grayscale,2-Sepia.... same as enum
public int selected;
}

ahora en adaptador

@Override
public void onBindViewHolder(FiltersAdapter.ViewHolder holder, int position) {
int typeOfItem = mDataSet.get(position).type
switch (mDataSet.get(position)) {
case 0:
holder.image.setImageResource(R.drawable.no_filter);
break;
case 1:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new GrayscaleTransformation())
.into(holder.image);
break;
case 2:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new SepiaFilterTransformation(mContext))
.into(holder.image);
break;
case 3:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new ContrastFilterTransformation(mContext, 2.0f))
.into(holder.image);
break;
case 4:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new InvertFilterTransformation(mContext))
.into(holder.image);
break;
case 5:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new PixelationFilterTransformation(mContext, 20))
.into(holder.image);
break;
case 6:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new SketchFilterTransformation(mContext))
.into(holder.image);
break;
case 7:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new SwirlFilterTransformation(mContext, 0.5f, 1.0f, new PointF(0.5f, 0.5f)))
.into(holder.image);
break;
case 8:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new BrightnessFilterTransformation(mContext, 0.5f))
.into(holder.image);
break;
case 9:
Picasso.with(mContext)
.load(R.drawable.no_filter)
.transform(new VignetteFilterTransformation(mContext, new PointF(0.5f, 0.5f),
new float[]{0.0f, 0.0f, 0.0f}, 0f, 0.75f))
.into(holder.image);
break;
default:
holder.image.setImageResource(R.drawable.no_filter);
break;
}
holder.title.setText(mDataSet.get(position).name());
if(mDataSet.get(position).selected == 0){
holder.title.setTypeface(null, Typeface.BOLD);
} else {
holder.title.setTypeface(null,Typeface.NORMAL);
}
}

no en cada clic o seleccione actualizar su lista, luego llame a notifydatasetChanged () del adaptador

Answer 3

Simplemente agregue esta línea debajo en bindView

holder.itemView.setBackgroundColor(Color.parseColor("#000000"));

funcionará para ti.

si desea resaltar el elemento seleccionado simplemente haga lo siguiente

establecerlo global

int selectedPosition=-1;

dentro deBindViewHolder-

public void onBindViewHolder(FiltersAdapter.ViewHolder holder, int position) {
if(selectedPosition==position)
holder.itemView.setBackgroundColor(Color.parseColor("#000000"));
else
holder.itemView.setBackgroundColor(Color.parseColor("#ffffff"));
holder.itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
selectedPosition=position;
notifyDataSetChanged();
}
});
}