通过尝试保存位图图像一直获取 "permission denied" 或 "no such file or directory"。我应该怎么办？

Question

我正在尝试通过此代码保存位图图像：

File sdcard = Environment.getExternalStorageDirectory();
            String filename = "test";
            File folder = new File(sdcard, "/Download");
            Log.v("ImageStorage1", "EXiST?: " + folder.exists());
            folder.mkdirs();
            Log.v("ImageStorage2", "EXIST!: " + folder.exists());
            Log.v("ImageStorage", "Folder: " + folder);
            File file = new File(folder, filename + ".jpg");

            try {
                FileOutputStream out = new FileOutputStream(file.getAbsoluteFile());
                result.compress(Bitmap.CompressFormat.JPEG, 90, out);
                out.flush();
                out.close();
            } catch (Exception e) {
                e.printStackTrace();
            }

我也在清单文件中使用：

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

但是我得到了这个：

V/ImageStorage1: EXiST?: true
V/ImageStorage2: EXIST!: true
W/System.err: java.io.FileNotFoundException: 
/storage/emulated/0/Download/test.jpg (Permission denied)
    W/System.err:     at java.io.FileOutputStream.open0(Native Method)
    W/System.err:     at java.io.FileOutputStream.open(FileOutputStream.java:287)
    W/System.err:     at java.io.FileOutputStream.<init>(FileOutputStream.java:223)
    W/System.err:     at java.io.FileOutputStream.<init>(FileOutputStream.java:171)

实际上，我的任务是存储到另一个文件夹，当我使用这个时：

File folder = new File(sdcard, "/kpi/test/a");

我正在

V/ImageStorage1: EXiST?: false
V/ImageStorage2: EXIST!: false
(No such file or directory)

即使有：

folder.mkdirs();

我尝试了很多，也浏览了很多，但没有找到答案:(

Answer 1

runtime permissions letting user to allow or deny any permission at runtime. use this lib Dexter library.also check an working exmple here

在您的 build.gradle

中包含该库

dependencies{
    implementation 'com.karumi:dexter:4.2.0'
}

此示例请求 WRITE_EXTERNAL_STORAGE.

Dexter.withActivity(this)
                .withPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE)
                .withListener(new PermissionListener() {
                    @Override
                    public void onPermissionGranted(PermissionGrantedResponse response) {
                        // permission is granted, open the camera
                    }

                    @Override
                    public void onPermissionDenied(PermissionDeniedResponse response) {
                        // check for permanent denial of permission
                        if (response.isPermanentlyDenied()) {
                            // navigate user to app settings
                        }
                    }

                    @Override
                    public void onPermissionRationaleShouldBeShown(PermissionRequest permission, PermissionToken token) {
                        token.continuePermissionRequest();
                    }
                }).check();

请求多个权限同时请求多个权限，可以使用withPermissions()方式。下面的代码请求 STORAGE 和 LOCATION permissions.

Dexter.withActivity(this)
                .withPermissions(
                        Manifest.permission.READ_EXTERNAL_STORAGE,
                        Manifest.permission.WRITE_EXTERNAL_STORAGE,
                        Manifest.permission.ACCESS_FINE_LOCATION)
                .withListener(new MultiplePermissionsListener() {
                    @Override
                    public void onPermissionsChecked(MultiplePermissionsReport report) {
                        // check if all permissions are granted
                        if (report.areAllPermissionsGranted()) {
                            // do you work now
                        }

                        // check for permanent denial of any permission
                        if (report.isAnyPermissionPermanentlyDenied()) {
                            // permission is denied permenantly, navigate user to app settings
                        }
                    }

                    @Override
                    public void onPermissionRationaleShouldBeShown(List<PermissionRequest> permissions, PermissionToken token) {
                        token.continuePermissionRequest();
                    }
                })
                .onSameThread()
                .check();

通过尝试保存位图图像一直获取 "permission denied" 或 "no such file or directory"。我应该怎么办？

Getting all the time "permission denied" or "no such file or directory" by trying to save Bitmap image. What should i do?

android

filenotfoundexception

permission-denied