将图片保存到外部存储< smartphone>中的图库

Question

我不能用相机拍照，而且它不能保存在外部目录中，也不能在imageView中显示。

在activity_main:有拍照按钮，有显示图像的imageView按钮。

在AndroidManifest.xml：

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

class MainActivity{    
      private Uri mImgFileUri;
       void onCreate(){ ...

        Button button = (Button)findViewById(R.id.button);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                imageCapture();
            }
        });

    }

    private void imageCapture() {
        File extDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM);

        File myPicDir = new File(extDir.getAbsolutePath()+"/MyPictures");
        if(!myPicDir.exists()){
            myPicDir.mkdirs();
        }
        Date dt = new Date();
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyMMdd-HHmmss");

        String fileName = dateFormat.format(dt)+".jpg";
        File imgFile = new File(myPicDir+"/"+fileName);
        mImgFileUri = Uri.fromFile(imgFile);
        Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        intent.putExtra(MediaStore.EXTRA_OUTPUT,mImgFileUri);
        startActivityForResult(intent,555);
    }

    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        if(requestCode == 555 && resultCode == RESULT_OK){
            String path = mImgFileUri.getPath();
            Bitmap bitmap = BitmapFactory.decodeFile(path);
            ImageView imageView = (ImageView)findViewById(R.id.imageView);
            imageView.setImageBitmap(bitmap);
        }
    }
}

得到了这个错误

Error :

Process: com.example.cameraimagecapture, PID: 22554
    android.os.FileUriExposedException: file:///storage/emulated/0/DCIM/MyPictures/20190630-165910.jpg exposed beyond app through ClipData.Item.getUri()
...MainActivity.imageCapture(MainActivity.java:57) >> startActivityForResult(intent,555);
...MainActivity.access$000(MainActivity.java:23) >> class MainActivity extends AppCompatActivity {} 
...MainActivity$1.onClick(MainActivity.java:36) >> imageCapture();

Answer 1

用于将图像放到屏幕上。

@Override
        protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
            super.onActivityResult(requestCode, resultCode, data);


            if (resultCode != RESULT_CANCELED) {
                if (requestCode == CAMERA_REQUEST) {
                    Bitmap photo = (Bitmap) data.getExtras().get("data");
                    imageView.setImageBitmap(photo);
                }


            }
    }

使用屏幕截图将照片保存到外部存储：

1)在活动中配置布局。示例: RelativeLayout

RelativeLayout RelativeLayout;

 RelativeLayout = (RelativeLayout) findViewById(R.id.RelativeLayout);

2)检测Bitmap格式的视图，如以下代码所示。

 private Bitmap getscreenshot(View view) {
        View v = view;
        v.setDrawingCacheEnabled(true);
        Bitmap bitmap = Bitmap.createBitmap(v.getDrawingCache());
        return bitmap;
    } 

3)设置此代码用于保存您的图像。

private void SaveImage(Bitmap finalBitmap) {

        String root = Environment.getExternalStoragePublicDirectory(
                Environment.DIRECTORY_PICTURES).toString();
        File myDir = new File(root + "/saved_images");
        myDir.mkdirs();
        Random generator = new Random();

        int n = 10000;
        n = generator.nextInt(n);
        String fname = "Image-" + n + ".jpg";
        File file = new File(myDir, fname);
        if (file.exists()) file.delete();
        try {
            FileOutputStream out = new FileOutputStream(file);
            finalBitmap.compress(Bitmap.CompressFormat.JPEG, 90, out);
            // sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED,
            //     Uri.parse("file://"+ Environment.getExternalStorageDirectory())));
            out.flush();
            out.close();

        } catch (Exception e) {
            e.printStackTrace();
        }

        MediaScannerConnection.scanFile(this, new String[]{file.toString()}, null,
                new MediaScannerConnection.OnScanCompletedListener() {
                    public void onScanCompleted(String path, Uri uri) {
                        Log.i("ExternalStorage", "Scanned " + path + ":");
                        Log.i("ExternalStorage", "-> uri=" + uri);
                    }
                });
    }

4)最后，使用所有这些代码来实现您的意图：

 Bitmap screenshota = getscreenshot(RelativeLayout);
     SaveImage(screenshota);