RecyclerView Cardview项目背景颜色更改单击其项目时

Question

我点击RecylerView项目时,我试图更改RecyclerView CardView背景的颜色(绿色),当我点击RecyclerView的下一个项目时,之前的项目必须更改/来到其原始颜色(粉红色),并选择项目颜色将变化,那就是绿色.有人能为我提供适当的解决方案.

Plss看到图像

我的课-:

public class RecylerAdapter extends  RecyclerView.Adapter<RecylerAdapter.ViewHolder>
{   private boolean isSelected;
    private final static int FADE_DURATION = 500;// milliseconds
    private int lastPosition = -1;
    Context cont;
  private  String[] strname;
    private int[] icon;
    public RecylerAdapter(Context con, String[] androidNames, int[] androidIcon)
    {   cont=con;
        strname=androidNames;
        icon=androidIcon;
    }
    class ViewHolder extends RecyclerView.ViewHolder
    {   private ImageView imgView;
        private TextView txtView;
        private CardView cardView;
        private SparseBooleanArray selectedItems = new SparseBooleanArray();

        public ViewHolder(final View itemView)
        {
            super(itemView);

            imgView = (ImageView) itemView.findViewById(R.id.imageView);
            txtView = (TextView) itemView.findViewById(R.id.txt);
            cardView = (CardView) itemView.findViewById(R.id.cv12);


            itemView.setOnClickListener(new View.OnClickListener()
            {
                @Override
                public void onClick(View v)
                {
                    cardView.isSelected = !cardView.isSelected;
                    notifyDataSetChanged();
                }
            });
        }
    }
    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)
    {
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.card_layout,parent,false);
        ViewHolder viewHolder = new ViewHolder(v);

        return viewHolder;
    }

    @TargetApi(Build.VERSION_CODES.JELLY_BEAN)
    @Override
    public void onBindViewHolder(ViewHolder holder, int i)
    {
        if(ViewHolder.isSelected)
        {
            holder.cardView.setBackground(Color.Green);
        }
        else{
            holder.cardView.setBackground(Color.Pink);
        }
        holder.txtView.setText(strname[i]);
        holder.imgView.setImageResource(icon[i]);
        setAnimation(holder.cardView, i);
    }
    @TargetApi(Build.VERSION_CODES.JELLY_BEAN)
    private void setAnimation(View viewToAnimate, int position)
    {
        // If the bound view wasn't previously displayed on screen, it's animated
        if (position > lastPosition)
        {
            //animation 1
            AlphaAnimation anim = new AlphaAnimation(0.0f, 1.0f);
            anim.setDuration(FADE_DURATION);
            viewToAnimate.startAnimation(anim);

            //animation 2
            Animation animation = AnimationUtils.loadAnimation(cont, android.R.anim.slide_in_left);
            viewToAnimate.startAnimation(animation);
            lastPosition = position;
        }
        else
        {
            Animation animation = AnimationUtils.loadAnimation(cont, android.R.anim.slide_in_left);
            viewToAnimate.startAnimation(animation);
            lastPosition = position;
        }
    }
    @Override
    public int getItemCount()
    {
        return strname.length;
    }
    public void setSelected(boolean selection){
        this.isSelected = selection;
    }
    public boolean isSelected(){
        return isSelected;
    }
}

Answer 1

这是关于使用模型类进行项目选择管理的全部内容:

MyModel.class:这是用于显示回收器视图的数据列表的类.添加一个布尔变量以进行选择和取消选择.

private boolean isSelected;

public void setSelected(boolean selection){
this.isSelected = selection;
}

public boolean isSelected(){
return isSelected;
}

现在点击你的适配器中的回收站视图:

myModel = list.get(position);
myModel.isSelected = !myModel.isSelected;
notifyDataSetChanged();

在适配器的onBindViewHolder方法中

    myModel = list.get(position);
    if(myModel.isSelected){
       itemView.setBackground(Color.Green);
    }else{
       itemView.setBackground(Color.Pink);
    }

使用此逻辑并检查,如果您发现任何困难,请告诉我.

您更新的代码,因为您没有使用模型类列表,因此您无法使用模型变量选择进行管理,请查看以下内容:

    public class RecylerAdapter extends RecyclerView.Adapter<RecylerAdapter.ViewHolder> {
    private boolean isSelected;
    private final static int FADE_DURATION = 500;// milliseconds
    private int lastPosition = -1;
    Context cont;
    private String[] strname;
    private int[] icon;
    private int selectedPosition = -1;

    public RecylerAdapter(Context con, String[] androidNames, int[] androidIcon) {
        cont = con;
        strname = androidNames;
        icon = androidIcon;
    }

    class ViewHolder extends RecyclerView.ViewHolder {
        private ImageView imgView;
        private TextView txtView;
        private CardView cardView;
        private SparseBooleanArray selectedItems = new SparseBooleanArray();

        public ViewHolder(final View itemView) {
            super(itemView);
            imgView = (ImageView) itemView.findViewById(R.id.imageView);
            txtView = (TextView) itemView.findViewById(R.id.txt);
            cardView = (CardView) itemView.findViewById(R.id.cv12);

            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    selectedPosition = getAdapterPosition();
                    notifyDataSetChanged();
                }
            });
        }
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.card_layout, parent, false);
        ViewHolder viewHolder = new ViewHolder(v);

        return viewHolder;
    }

    @TargetApi(Build.VERSION_CODES.JELLY_BEAN)
    @Override
    public void onBindViewHolder(ViewHolder holder, int i) {
        if (selectedPosition == i) {
            holder.cardView.setBackground(Color.Green);
        } else {
            holder.cardView.setBackground(Color.Pink);
        }
        holder.txtView.setText(strname[i]);
        holder.imgView.setImageResource(icon[i]);
        setAnimation(holder.cardView, i);
    }

    @TargetApi(Build.VERSION_CODES.JELLY_BEAN)
    private void setAnimation(View viewToAnimate, int position) {
        // If the bound view wasn't previously displayed on screen, it's animated
        if (position > lastPosition) {
            //animation 1
            AlphaAnimation anim = new AlphaAnimation(0.0f, 1.0f);
            anim.setDuration(FADE_DURATION);
            viewToAnimate.startAnimation(anim);

            //animation 2
            Animation animation = AnimationUtils.loadAnimation(cont, android.R.anim.slide_in_left);
            viewToAnimate.startAnimation(animation);
            lastPosition = position;
        } else {
            Animation animation = AnimationUtils.loadAnimation(cont, android.R.anim.slide_in_left);
            viewToAnimate.startAnimation(animation);
            lastPosition = position;
        }
    }

    @Override
    public int getItemCount() {
        return strname.length;
    }
}