在 RecyclerView 上突出显示所选项目

Question

我的应用包含两个片段（我们称它们为 A 和 B）。 Fragment A 显示 RecyclerView，Fragment B 显示该 Recycler 上所选项目的内容。在小屏幕和普通屏幕上，每个片段都显示在其 Activity 上，但在大屏幕上，两个片段同时显示，所以我希望当用户点击一个时，在多窗格 activity RecyclerView 中的项目会突出显示。我在 Whosebug 上发现了很多这样的问题，但它们不适用于我的适配器。

final FragmentCallback activity;
final FragmentA fragment; //The fragment with the RecyclerView

Cursor cursor;
int idColumnIndex;
int titleColumnIndex;
int balanceColumnIndex;

public MoneyboxesAdapter(FragmentCallback activity, FragmentA frag){
    this.activity = activity;
    this.fragment = frag;
}

public void swapCursor(Cursor c){
    // Method called whenever the data stored on the DB has changed
    this.cursor = c; //Updates the current cursor
    if(cursor!=null){
        cursor.moveToFirst();
        idColumnIndex = cursor.getColumnIndex(MoneyboxProvider.COLUMN_MONEYBOX_ID);
        titleColumnIndex = cursor.getColumnIndex(MoneyboxProvider.COLUMN_MONEYBOX_TITLE);
        balanceColumnIndex = cursor.getColumnIndex(MoneyboxProvider.COLUMN_MONEYBOX_BALANCE);
    }
    notifyDataSetChanged();
}

@Override
public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
    CardView v = (CardView) LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.moneybox_item, viewGroup, false);
    return new ViewHolder(v);
}

@Override
public void onBindViewHolder(final ViewHolder viewHolder, final int i) {

    // Sets up the views
    cursor.moveToPosition(i);
    final long id = getItemId(i);
    final String moneyboxTitle = cursor.getString(titleColumnIndex);
    final float balance = cursor.getFloat(balanceColumnIndex);
    viewHolder.title.setText(moneyboxTitle);
    viewHolder.balance.setText(balance);


    viewHolder.cardView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            activity.onLoadMoneybox(id);
            //TODO: Show selected on multipane
        }

    });


}

@Override
public int getItemCount() {
    return cursor!=null?cursor.getCount():0;
}

public long getItemId(int position){
    // Gets the ID in the DB of a moneybox
    cursor.moveToPosition(position);
    return cursor.getLong(idColumnIndex);
}


static class ViewHolder extends RecyclerView.ViewHolder{

    CardView cardView;
    TextView title;
    TextView balance;
    ImageView threeDots;

    public ViewHolder(CardView itemView) {
        super(itemView);
        cardView = itemView;
        title = (TextView) itemView.findViewById(R.id.moneybox_item_title);
        balance = (TextView) itemView.findViewById(R.id.moneybox_item_balance);
        threeDots = (ImageView)itemView.findViewById(R.id.three_dots_moneybox);
    }


}

Answer 1

为列表项创建一个选择器并设置 view.setSelected(true)；对于已选择的特定位置，并跟踪最后选择的视图，如果用户单击新行项目，则将其设置为 false。

Answer 2

您可以按照下面的代码片段进行操作。

            class ViewHolder extends RecyclerView.ViewHolder implements OnClickListener {

                public ViewHolder(View view) {
                    // your code
                    view.setOnClickListener(this)
                }

                @Override
                public void onClick(View v) {
                    int position = getPosition();
                    // your changes for changing color
                    notifyDataSetChanged();
                }
            }

在 RecyclerView 上突出显示所选项目

Highlight selected item on a RecyclerView

android

android-sqlite

android-recyclerview