使用Android Studio

Question

我是Android Studio新手。我使用Retrofit作为服务器请求。我想在数据库中发送图像，并希望在同一图像中显示。我该怎么办？

Answer 1

1. 将图像转换为字节数组并使用db query

   应用它

   public static byte[] getBytes(Bitmap bitmap) {
       ByteArrayOutputStream stream = new ByteArrayOutputStream();
       bitmap.compress(CompressFormat.PNG, 0, stream);
       return stream.toByteArray();
   }
   

2. 从db获取字节数组后，您应该将其转换为图像

   public static Bitmap getImage(byte[] image) {
       return BitmapFactory.decodeByteArray(image, 0, image.length);
   }
   

3. 创建对象的类并声明列表视图的自定义适配器：

   //your object's class
   public class Book {
       String mName;
       long mPrice;
       Bitmap mPhoto;
   }
   
   //custom adapter
   public class CustomAdapter extends ArrayAdapter<Book> {
       public CustomAdapter(Context context, List<Book> books) {
           super(context, 0, books);
       }
   
       @Override
       public View getView(int position, View convertView, ViewGroup parent) {
           View row = convertView;
           if(row == null) {
               // inflate row layout and assign to 'row'
           }
           final thisBook = getItem(position);
           final ImageView photo = row.findViewById(R.id.photo);
           photo.setImageBitmap(thisBook.mPhoto);
   
           return row;
       }
   }
   

另请尝试tutorial