Question

我遵循了Saving an image from ImageView into internal storage的回答，但仍然无法保存任何内容。我的代码在这里：

// Icon names in the order of icons to be display.
List<Map<String,String>> iconNames = [
  {'unselected': 'home', 'selected': 'home-selected'},
  {'unselected': 'community', 'selected': 'community-selected'},
  {'unselected': 'post', 'selected': 'post-selected'},
  {'unselected': 'notification', 'selected': 'notification-selected'},
  {'unselected': 'settings', 'selected': 'settings-selected'},
]; 

int _currentIndex = 0;

@override
  Widget build(BuildContext context) {
    return Scaffold(
      bottomNavigationBar: ClipRRect(
        borderRadius: BorderRadius.vertical(top: Radius.circular(15)),
        child: BottomNavigationBar(
            type: BottomNavigationBarType.fixed, // add this
            currentIndex: _currentIndex,
            onTap: (index) {
              setState(() {
                _currentIndex = index;
              });
            },
            items: [
              for(int i = 0; i < iconNames.length; ++i)
                BottomNavigationBarItem(
                  icon: SvgPicture.asset(
                    // icon name based on selection
                    iconNames[i][i == _currentIndex ? 'selected' : 'unselected'],
                  ),
                  title: Text(''),
                )
            ],
        ),
      ),
    );
  }

使用这种方法，我得到带有messae的IOExeception：public void buttonPickImage(View view) { FileOutputStream fos; bitmap = ((BitmapDrawable)imageView.getDrawable()).getBitmap(); Random rng = new Random(); int n = rng.nextInt(1000); try { File sdCard = Environment.getExternalStorageDirectory(); File dir = new File(sdCard.getAbsolutePath() + "/BAC"); bool = dir.mkdir(); File file = new File(dir, "BAC_"+n+".jpg"); fos = new FileOutputStream(file); bitmap.compress(Bitmap.CompressFormat.JPEG,100,fos); fos.flush(); fos.close(); Toast.makeText(getApplicationContext(),"Image sauvegardée"+bool,Toast.LENGTH_SHORT).show(); }catch (java.io.IOException e){ e.printStackTrace(); Toast.makeText(getApplicationContext(),"IOException: " + e.getMessage(),Toast.LENGTH_SHORT).show(); } }

我也尝试过将其保存到内部存储中，但对我不起作用： https://www.tutorialspoint.com/how-to-write-an-image-file-in-internal-storage-in-android 使用这种方法，程序可以运行，但是布尔型mkdir给我错误。

感谢您的帮助

Answer 1

最后使用 Media Store 代替getExternalStorageDirectory作为

此方法在API级别29中已弃用。为了提高用户隐私，不建议直接访问共享/外部存储设备。当应用程序定位到Build.VERSION_CODES.Q时，此方法返回的路径不再可供应用程序直接访问。通过迁移到Context＃getExternalFilesDir（String），MediaStore或Intent＃ACTION_OPEN_DOCUMENT之类的替代方案，应用程序可以继续访问共享/外部存储中存储的内容。

MediaStore也很有用，因为它允许您在Android Gallery应用中获取图像。

所以我的解决方法是：

ImageView imageView = findViewById(R.id.image);
        Bitmap bitmap = ((BitmapDrawable)imageView.getDrawable()).getBitmap();

        ContentValues values = new ContentValues();
        values.put(MediaStore.Images.Media.TITLE, "any_picture_name");
        values.put(MediaStore.Images.Media.BUCKET_ID, "test");
        values.put(MediaStore.Images.Media.DESCRIPTION, "test Image taken");
        values.put(MediaStore.Images.Media.MIME_TYPE, "image/jpeg");
        Uri uri = getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
        OutputStream outstream;
        try {
            outstream = getContentResolver().openOutputStream(uri);
            bitmap.compress(Bitmap.CompressFormat.JPEG, 70, outstream);
            outstream.close();
            Toast.makeText(getApplicationContext(),"Success",Toast.LENGTH_LONG).show();
        } catch (IOException e) {
            e.printStackTrace();
            Toast.makeText(getApplicationContext(),e.getMessage(),Toast.LENGTH_LONG).show();
        }

仍然感谢@blackapps向我解释了有关IOexception，mkdir和Toast的一些基本知识。反正还是有用的。

将图像从ImageView保存到存储

1 个答案: