Question

我有一个recyclelerview在线显示json文件中的项目，recyclelerview在每个列表项中也有一个缩略图。

当我点击某个项目时，它会启动一项新活动，如何将从服务器获取的缩略图图像传递给新活动？

这是我的新活动代码：

public class ItemModal extends AppCompatActivity {

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_item_modal);

        TextView ItemNameV = (TextView) findViewById(R.id.textView);
        TextView ItemDescV = (TextView) findViewById(R.id.textView2);
        TextView ItemPriceV = (TextView) findViewById(R.id.textView3);
        ImageView ItemImageV = (ImageView) findViewById(R.id.imageView);

        String itemName = getIntent().getStringExtra("ItemName");
        String itemDesc = getIntent().getStringExtra("ItemDesc");
        String itemPrice = getIntent().getStringExtra("ItemPrice");
        String itemImage = getIntent().getStringExtra("ItemImage");

        ItemNameV.setText(itemName);
        ItemDescV.setText(itemDesc);
        ItemPriceV.setText(itemPrice);
        ItemImageV.setId(Integer.parseInt(itemImage));
    }



}

以下是适配器代码：

public class AdapterItems extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

    private Context context;
    private LayoutInflater inflater;
    List<DataItems> data= Collections.emptyList();
    DataItems current;
    int currentPos=0;

    // create constructor to innitilize context and data sent from MainActivity
    public AdapterItems(Context context, List<DataItems> data){
        this.context=context;
        inflater= LayoutInflater.from(context);
        this.data=data;
    }

    // Inflate the layout when viewholder created
    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view=inflater.inflate(R.layout.container_items, parent,false);
        MyHolder holder=new MyHolder(view);
        return holder;
    }

    // Bind data
    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {

        // Get current position of item in recyclerview to bind data and assign values from list
        MyHolder myHolder= (MyHolder) holder;
        DataItems current=data.get(position);
        myHolder.textItemName.setText(current.itemName);
        myHolder.textDesc.setText(current.itemDesc);
        myHolder.textPrice.setText("# " + current.price);
        myHolder.textPrice.setTextColor(ContextCompat.getColor(context, R.color.colorAccent));

        // load image into imageview using glide
        Glide.with(context).load(current.itemImage)
                .placeholder(R.drawable.ic_img_error)
                .error(R.drawable.ic_img_error)
                .into(myHolder.ivItem);

    }

    // return total item from List
    @Override
    public int getItemCount() {
        return data.size();
    }


    class MyHolder extends RecyclerView.ViewHolder implements View.OnClickListener{

        TextView textItemName;
        ImageView ivItem;
        TextView textDesc;
        TextView textPrice;

        // create constructor to get widget reference
        public MyHolder(View itemView) {
            super(itemView);
            textItemName = (TextView) itemView.findViewById(R.id.textItemName);
            ivItem = (ImageView) itemView.findViewById(R.id.ivItem);
            textDesc = (TextView) itemView.findViewById(R.id.textDesc);
            textPrice = (TextView) itemView.findViewById(R.id.textPrice);

            itemView.setOnClickListener(this);
        }

        @Override
        public void onClick(View v) {

            Intent intent = new Intent(context, ItemModal.class);
            intent.putExtra("ItemName", textItemName.getText().toString());
            intent.putExtra("ItemImage", ivItem.getId());
            intent.putExtra("ItemDesc", textDesc.getText().toString());
            intent.putExtra("ItemPrice", textPrice.getText().toString());
            Toast.makeText(context, textDesc.getText().toString() , Toast.LENGTH_SHORT ).show();
            context.startActivity(intent);
        }
    }

}

以下是开始新活动的代码：

public void onClick(View v) {

            Intent intent = new Intent(context, ItemModal.class);
            intent.putExtra("ItemName", textItemName.getText().toString());
            intent.putExtra("ItemImage", ivItem.getId());
            intent.putExtra("ItemDesc", textDesc.getText().toString());
            intent.putExtra("ItemPrice", textPrice.getText().toString());
            Toast.makeText(context, textDesc.getText().toString() , Toast.LENGTH_SHORT ).show();
            context.startActivity(intent);
        }

这里我只是传递了没有帮助的图像的ID。

Answer 1

MyHolder课程：

isset

适配器onBindViewHolder：

class MyHolder extends RecyclerView.ViewHolder implements View.OnClickListener{
    String imageUrl;
    // .....

    @Override
    public void onClick(View v) {
        // ...
        intent.putExtra("ItemImage", imageUrl);
        context.startActivity(intent);
    }
}

ItemModal类：

@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {

    // ...
    myHolder.imageUrl = current.itemImage;

}

Answer 2

将视图持有者的点击功能更改为类似于下面的

@Override
        public void onClick(View v) {
DataItems current=data.get(getAdapterPosition());
//getAdapterPosition() will return the clicked position
            Intent intent = new Intent(context, ItemModal.class);
            intent.putExtra("ItemName", current.itemName);
            intent.putExtra("ItemImage", current.itemImage);
            intent.putExtra("ItemDesc", current.itemDesc);
            intent.putExtra("ItemPrice", "# " + current.price);
            Toast.makeText(context, textDesc.getText().toString() , Toast.LENGTH_SHORT ).show();
            context.startActivity(intent);
        }

再次，您可以使用Glide在itemMod.class活动中加载图像在Glide中，您可以定义它可以从缓存加载还是再次从网络重新加载如果您从缓存设置它不会使用网络下载图像，它将重用下载的文件，以回收Recyclerview

如何将图像从网络传递到recyclerview中的另一个活动

2 个答案: