我有两个布局文件,如下所示。使用RecyclerView适配器更改运行时布局屏幕
如果数据存在于列表中,则显示此布局。
,当列表为空,然后我告诉这个布局。
现在,我想在运行时更改布局。当用户从列表中删除最后一个项目时,我想将布局更改为第二个图像中显示的“清空购物车布局”。
在RecyclerView适配器getItemCount()
方法,如果列表为空或null,则我回算不算1
否则我回到list.size()
这是我的适配器代码。
public class CheckOutAdapter extends RecyclerView.Adapter<CheckOutAdapter.ViewHolder> {
public ArrayList<Design> designList;
private Context context;
private LayoutInflater layoutInflater;
public CheckOutAdapter(Context context, ArrayList<Design> designList) {
this.designList = designList;
this.context = context;
this.layoutInflater = LayoutInflater.from(context);
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if(designList.isEmpty() || designList == null || designList.size() == 0) {
View view = layoutInflater.inflate(R.layout.empty_cart, parent, false);
return new ViewHolder(view);
} else {
View view = layoutInflater.inflate(R.layout.checkout_single_design, parent, false);
return new ViewHolder(view);
}
}
@Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
final Design design = designList.get(position);
holder.tvQuality.setText(design.qualityName);
holder.tvDesign.setText(design.designName);
holder.tvShade.setText(design.name);
holder.tvAmount.setText("₹ " + design.amount);
Picasso.with(context).load(design.image).into(holder.ivDesign);
if (design.pcs != 0) {
holder.btPcsCount.setText(Integer.toString(design.pcs));
}
holder.ivDelete.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
openDialog(design);
}
});
//other ClickListeners.
}
@Override
public int getItemCount() {
if (designList == null || designList.isEmpty() || designList.size() == 0) {
return 1;
} else {
return designList.size();
}
}
public static class ViewHolder extends RecyclerView.ViewHolder {
public LinearLayout llPer;
public Button btPlus, btMinus, btPcsCount, btAddCart;
public ImageView ivDesign, ivDelete;
public TextView tvDesign, tvQuality, tvShade, tvAmount, tvDiscAmt, tvDisPer;
public ViewHolder(View itemView) {
super(itemView);
llPer = (LinearLayout) itemView.findViewById(R.id.llPer);
btPlus = (Button) itemView.findViewById(R.id.btPlus);
//other findViewByIds
}
}
public void openDialog(final Design design) {
AlertDialog.Builder builder = new AlertDialog.Builder(context);
builder.setTitle("Confirm");
builder.setMessage("Remove item from cart?");
builder.setPositiveButton("YES", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
designList.remove(design);
notifyDataSetChanged();
saveSharedPref(context, "cart", new Gson().toJson(designList));
Toast.makeText(context, "deleted", Toast.LENGTH_SHORT).show();
dialog.dismiss();
}
});
builder.setNegativeButton("NO", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
}
});
AlertDialog alert = builder.create();
alert.show();
}
}
我得到NullPointerException接近onBindViewHolder
。我不知道它为什么会坠毁。请提出建议。
您需要重写getItemViewType来设置运行时布局 –