如何在 RecyclerView 中突出显示所选项目 [英] How to highlight selected item in RecyclerView
本文介绍了如何在 RecyclerView 中突出显示所选项目的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我使用 RecyclerView 在我的图像编辑应用程序中显示缩略图.它的每个项目都包含一个 ImageView(缩略图)和一个 textView.在我的应用程序中，我想仅突出显示当前选定的缩略图点击.浏览了所有关于 SO 的相关帖子，但找不到任何更好的解决方案.
I have used RecyclerView for showing thumbnails in my Image Editing app.Each item of its comprises of a ImageView(thumbnail) and a textView.In my application I want to highlight only current selected thumbnail when clicked.Gone through all the related posts on SO but couldn't find any better solution.
我的适配器类
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);
}
}
}
片段代码
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) {
}
}));
}
推荐答案
只需在 bindView 中添加以下行
Just add this below line in bindView
holder.itemView.setBackgroundColor(Color.parseColor("#000000"));
会为你工作.
如果您想突出显示所选项目，请执行以下操作
if you want to highlight selected item just do like below
全局设置
int selectedPosition=-1;
内部 onBindViewHolder-
inside onBindViewHolder-
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();
}
});
}
这篇关于如何在 RecyclerView 中突出显示所选项目的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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