Question

我收到错误，W / System.err：java.io.FileNotFoundException：open failed：EACCES（Permission denied）

代码有：

Environment.getExternalStorageDirectory().getAbsolutePath()

AndroidManifest.xml有：

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

build.gradle有：

targetSdkVersion is 23

Answer 1

您可能没有请求权限执行这些操作，您必须要求用户向您的应用授予这些权限。请参阅此相关帖子：Storage permission error in Marshmallow

Answer 2

问题是需要Lollipop的安全许可

public static boolean checkReadStoragePermission(final Context context){
        int currentAPIVersion = Build.VERSION.SDK_INT;

        if(currentAPIVersion>= 23)
        {
            if (ContextCompat.checkSelfPermission(context, Manifest.permission.READ_EXTERNAL_STORAGE)
                    != PackageManager.PERMISSION_GRANTED) {

                if (ActivityCompat.shouldShowRequestPermissionRationale((Activity) context,
                        Manifest.permission.READ_EXTERNAL_STORAGE)) {

                    AlertDialog.Builder alertBuilder = new AlertDialog.Builder(context);
                    alertBuilder.setCancelable(true);
                    alertBuilder.setTitle("Storage Permission Necessary");
                    alertBuilder.setMessage("External storage permission is necessary");
                    alertBuilder.setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {

                        public void onClick(DialogInterface dialog, int which) {
                            ActivityCompat.requestPermissions((Activity) context,
                                    new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},
                                    MY_PERMISSIONS_REQUEST_READ_EXTERNAL_STORAGE);
                        }
                    });
                    AlertDialog alert = alertBuilder.create();
                    alert.show();

                } else {
                    ActivityCompat.requestPermissions((Activity) context,
                            new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},
                            MY_PERMISSIONS_REQUEST_READ_EXTERNAL_STORAGE);
                }
                return false;
            } else {
                return true;
            }
        } else {
            return true;
        }
    }


   public static boolean checkWriteStoragePermission(final Context context){
        int currentAPIVersion = Build.VERSION.SDK_INT;

        if(currentAPIVersion>= 23)
        {
            if (ContextCompat.checkSelfPermission(context, Manifest.permission.WRITE_EXTERNAL_STORAGE)
                    != PackageManager.PERMISSION_GRANTED) {

                if (ActivityCompat.shouldShowRequestPermissionRationale((Activity) context,
                        Manifest.permission.WRITE_EXTERNAL_STORAGE)) {

                    AlertDialog.Builder alertBuilder = new AlertDialog.Builder(context);
                    alertBuilder.setCancelable(true);
                    alertBuilder.setTitle("Storage Permission Necessary");
                    alertBuilder.setMessage("External storage permission is necessary");
                    alertBuilder.setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {

                        public void onClick(DialogInterface dialog, int which) {
                            ActivityCompat.requestPermissions((Activity) context,
                                    new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
                                    MY_PERMISSIONS_REQUEST_WRITE_EXTERNAL_STORAGE);
                        }
                    });
                    AlertDialog alert = alertBuilder.create();
                    alert.show();

                } else {
                    ActivityCompat.requestPermissions((Activity) context,
                            new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
                            MY_PERMISSIONS_REQUEST_WRITE_EXTERNAL_STORAGE);
                }
                return false;
            } else {
                return true;
            }
        } else {
            return true;
        }
    }

AndroidMy 6.0 targetSdkVersion 23打开失败：EACCES（权限被拒绝）

2 个答案: