我想在数据库中存储一些图像,稍后恢复它们并在自定义 ListView
上显示它们。我该怎么做?
这是我到目前为止所做的:
//here, we are making a folder named picFolder to store pics taken by the camera using this application
dir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).getPath() + "/picFolder/";
File newdir = new File(dir);
if(!newdir.exists()){
newdir.mkdirs();
}
//Switch cases are
案例 R.id.btnPhotoGallary2:
Intent gallaryIntent = new Intent(Intent.ACTION_PICK,
android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(gallaryIntent , TAKE_GALLARY_CODE);//one can be replced with any action code
break;
case R.id.btnPhotoCamera1:
count++;
String file = dir+count+".jpg";
File newfile = new File(file);
try {
newfile.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
capturedPhotoUri = Uri.fromFile(newfile);
Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, capturedPhotoUri);
startActivityForResult(cameraIntent, TAKE_CAMERA_CODE);
break;
//将照片设置为 Button/ImageView
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
super.onActivityResult(requestCode, resultCode, data);
switch (requestCode) {
case 0://Captured photo from Camera
if(resultCode == RESULT_OK){
String pathNamePhoto = capturedPhotoUri.getPath().toString();
System.out.println("Photo Path Is :"+pathNamePhoto);
d = BitmapDrawable.createFromPath(pathNamePhoto);
ivProfile.setImageDrawable(d);
Log.d("CameraDemo", "Pic saved");
Log.v("CapturedPhoto PATH ==>> ",pathNamePhoto);
pd.setProfImagepath(pathNamePhoto);
}
dialog.dismiss();
break;
case 1://Select Image from Gallery
if(resultCode == RESULT_OK){
Uri selImageUri = data.getData();
String pathNameImage = getPath(selImageUri);
System.out.println("Image Path Is :"+pathNameImage);
ivProfile.setImageURI(selImageUri);
Log.d("GallaryDemo", "Get Pic ");
Log.v("IMAGE PATH ==>> ",pathNameImage);
pd.setProfImagepath(pathNameImage);
}
dialog.dismiss();
break;
}
}
//获取图片真实路径
@SuppressWarnings("deprecation")
public String getPath(Uri uri) {
String[] projection = { MediaStore.Images.Media.DATA };
Cursor cursor = managedQuery(uri, projection, null, null, null);
int column_index = cursor
.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
}
最佳答案
嗯,我对在数据库中存储图像的建议是:不要。 效果不佳,最好使用路径存储。这在 this question 上讨论过.
但是。如果你真的出于任何原因存储它。尝试将图像编码为 Base64 String
,并将其存储在您的数据库中。
Android 有 Base64 class
为了这。尝试使用以下代码 fragment 进行编码:
Bitmap bitmap = BitmapFactory.decodeFile("image.jpg");
ByteArrayOutputStream baos = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos); // Could be Bitmap.CompressFormat.PNG or Bitmap.CompressFormat.WEBP
byte[] bai = baos.toByteArray();
String base64Image = Base64.encodeToString(bai, Base64.DEFAULT);
// Call your method to save this string on the DB here.
并且您必须尝试以下操作对其进行解码:
byte[] data = Base64.decode(base64Image, Base64.DEFAULT);
Bitmap bm;
BitmapFactory.Options opt = new BitmapFactory.Options();
opt.inMutable = true;
bm = BitmapFactory.decodeByteArray(data, 0, data.length, opt);
// Now do whatever you want with the Bitmap.
您可以查看 Bitmap
类的文档 here .
关于android - 如何将图像存储在数据库中并在 ListView 中显示,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/30987876/