android.os.FileUriExposedException: file:///storage/emulated/0/test.txt exposed beyond app through Intent.getData()

问题

The app is crashing when I'm trying to open a file. It works below Android Nougat, but on Android Nougat it crashes. It only crashes when I try to open a file from the SD card, not from the system partition. Some permission problem?

Sample code:

File file = new File("/storage/emulated/0/test.txt");
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(file), "text/*");
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent); // Crashes on this line

Log:

android.os.FileUriExposedException: file:///storage/emulated/0/test.txt exposed beyond app through Intent.getData()

Edit:

When targeting Android Nougat, file:// URIs are not allowed anymore. We should use content:// URIs instead. However, my app needs to open files in root directories. Any ideas?

回答1:

If your targetSdkVersion >= 24, then we have to use FileProvider class to give access to the particular file or folder to make them accessible for other apps. We create our own class inheriting FileProvider in order to make sure our FileProvider doesn't conflict with FileProviders declared in imported dependencies as described here.

Steps to replace file:// URI with content:// URI:

• Add a class extending FileProvider

  public class GenericFileProvider extends FileProvider {}
  

• Add a FileProvider <provider> tag in AndroidManifest.xml under <application> tag. Specify a unique authority for the android:authorities attribute to avoid conflicts, imported dependencies might specify ${applicationId}.provider and other commonly used authorities.

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    ...
    <application
        ...
        <provider
            android:name=".GenericFileProvider"
            android:authorities="${applicationId}.provider"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/provider_paths"/>
        </provider>
    </application>
</manifest>

• Then create a provider_paths.xml file in res/xml folder. Folder may be needed to created if it doesn't exist. The content of the file is shown below. It describes that we would like to share access to the External Storage at root folder (path=".") with the name external_files.

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path name="external_files" path="."/>
</paths>

• The final step is to change the line of code below in

  Uri photoURI = Uri.fromFile(createImageFile());
  

  to

  Uri photoURI = FileProvider.getUriForFile(context, context.getApplicationContext().getPackageName() + ".provider", createImageFile());
  

• Edit: If you're using an intent to make the system open your file, you may need to add the following line of code:

  intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
  

Please refer, full code and solution has been explained here.

回答2:

Besides the solution using the FileProvider, there is another way to work around this. Simply put

StrictMode.VmPolicy.Builder builder = new StrictMode.VmPolicy.Builder();
StrictMode.setVmPolicy(builder.build());

in Application.onCreate(). In this way the VM ignores the file URI exposure.

Method

builder.detectFileUriExposure()

enables the file exposure check, which is also the default behavior if we don't setup a VmPolicy.

I encountered a problem that if I use a content:// URI to send something, some apps just can't understand it. And downgrading the target SDK version is not allowed. In this case my solution is useful.

Update:

As mentioned in the comment, StrictMode is diagnostic tool, and is not supposed to be used for this problem. When I posted this answer a year ago, many apps can only receive File uris. They just crash when I tried to send a FileProvider uri to them. This is fixed in most apps now, so we should go with the FileProvider solution.

回答3:

If your app targets API 24+, and you still want/need to use file:// intents, you can use hacky way to disable the runtime check:

if(Build.VERSION.SDK_INT>=24){
   try{
      Method m = StrictMode.class.getMethod("disableDeathOnFileUriExposure");
      m.invoke(null);
   }catch(Exception e){
      e.printStackTrace();
   }
}

Method StrictMode.disableDeathOnFileUriExposure is hidden and documented as:

/**
* Used by lame internal apps that haven't done the hard work to get
* themselves off file:// Uris yet.
*/

Problem is that my app is not lame, but rather doesn't want to be crippled by using content:// intents which are not understood by many apps out there. For example, opening mp3 file with content:// scheme offers much fewer apps than when opening same over file:// scheme. I don't want to pay for Google's design faults by limiting my app's functionality.

Google wants developers to use content scheme, but the system is not prepared for this, for years apps were made to use Files not "content", files can be edited and saved back, while files served over content scheme can't be (can they?).

回答4:

If targetSdkVersion is higher than 24, then FileProvider is used to grant access.

Create an xml file(Path: res\xml) provider_paths.xml

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path name="external_files" path="."/>
</paths>

Add a Provider in AndroidManifest.xml

    <provider
        android:name="android.support.v4.content.FileProvider"
        android:authorities="${applicationId}.provider"
        android:exported="false"
        android:grantUriPermissions="true">
        <meta-data
            android:name="android.support.FILE_PROVIDER_PATHS"
            android:resource="@xml/provider_paths"/>
    </provider>

If you are using androidx, the FileProvider path should be:

 android:name="androidx.core.content.FileProvider"

and replace

Uri uri = Uri.fromFile(fileImagePath);

to

Uri uri = FileProvider.getUriForFile(MainActivity.this, BuildConfig.APPLICATION_ID + ".provider",fileImagePath);

Edit: While you're including the URI with an Intent make sure to add below line:

intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);

and you are good to go. Hope it helps.

回答5:

If your targetSdkVersion is 24 or higher, you can not use file: Uri values in Intents on Android 7.0+ devices.

Your choices are:

1. Drop your targetSdkVersion to 23 or lower, or

2. Put your content on internal storage, then use FileProvider to make it available selectively to other apps

For example:

Intent i=new Intent(Intent.ACTION_VIEW, FileProvider.getUriForFile(this, AUTHORITY, f));

i.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
startActivity(i);

(from this sample project)

回答6:

First you need to add a provider to your AndroidManifest

  <application
    ...>
    <activity>
    .... 
    </activity>
    <provider
        android:name="android.support.v4.content.FileProvider"
        android:authorities="com.your.package.fileProvider"
        android:grantUriPermissions="true"
        android:exported="false">
        <meta-data
            android:name="android.support.FILE_PROVIDER_PATHS"
            android:resource="@xml/file_paths" />
    </provider>
  </application>

now create a file in xml resource folder (if using android studio you can hit Alt + Enter after highlighting file_paths and select create a xml resource option)

Next in the file_paths file enter

<?xml version="1.0" encoding="utf-8"?>
<paths>
  <external-path path="Android/data/com.your.package/" name="files_root" />
  <external-path path="." name="external_storage_root" />
</paths>

This example is for external-path you can refere here for more options. This will allow you to share files which are in that folder and its sub-folder.

Now all that's left is to create the intent as follows:

    MimeTypeMap mime = MimeTypeMap.getSingleton();
    String ext = newFile.getName().substring(newFile.getName().lastIndexOf(".") + 1);
    String type = mime.getMimeTypeFromExtension(ext);
    try {
        Intent intent = new Intent();
        intent.setAction(Intent.ACTION_VIEW);
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
            intent.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
            Uri contentUri = FileProvider.getUriForFile(getContext(), "com.your.package.fileProvider", newFile);
            intent.setDataAndType(contentUri, type);
        } else {
            intent.setDataAndType(Uri.fromFile(newFile), type);
        }
        startActivityForResult(intent, ACTIVITY_VIEW_ATTACHMENT);
    } catch (ActivityNotFoundException anfe) {
        Toast.makeText(getContext(), "No activity found to open this attachment.", Toast.LENGTH_LONG).show();
    }

EDIT: I added the root folder of the sd card in the file_paths. I have tested this code and it does work.

回答7:

@palash k answer is correct and worked for internal storage files, but in my case I want to open files from external storage also, my app crashed when open file from external storage like sdcard and usb, but I manage to solve the issue by modifying provider_paths.xml from the accepted answer

change the provider_paths.xml like below

<?xml version="1.0" encoding="utf-8"?>
 <paths xmlns:android="http://schemas.android.com/apk/res/android">

<external-path path="Android/data/${applicationId}/" name="files_root" />

<root-path
    name="root"
    path="/" />

</paths>

and in java class(No change as the accepted answer just a small edit)

Uri uri=FileProvider.getUriForFile(getActivity(), BuildConfig.APPLICATION_ID+".provider", File)

This help me to fix the crash for files from external storages, Hope this will help some one having same issue as mine :)

回答8:

Just paste the below code in activity onCreate()

StrictMode.VmPolicy.Builder builder = new StrictMode.VmPolicy.Builder(); StrictMode.setVmPolicy(builder.build());

It will ignore URI exposure

回答9:

My Solution was to 'Uri.parse' the File Path as String, instead of using Uri.fromFile().

String storage = Environment.getExternalStorageDirectory().toString() + "/test.txt";
File file = new File(storage);
Uri uri;
if (Build.VERSION.SDK_INT < 24) {
    uri = Uri.fromFile(file);
} else {
    uri = Uri.parse(file.getPath()); // My work-around for new SDKs, doesn't work in Android 10.
}
Intent viewFile = new Intent(Intent.ACTION_VIEW);
viewFile.setDataAndType(uri, "text/plain");
startActivity(viewFile);

Seems that fromFile() uses A file pointer, which I suppose could be insecure when memory addresses are exposed to all apps. But A file path String never hurt anybody, so it works without throwing FileUriExposedException.

Tested on API levels 9 to 27! Successfully opens the text file for editing in another app. Does not require FileProvider, nor the Android Support Library at all.

回答10:

Just paste the below code in activity onCreate().

StrictMode.VmPolicy.Builder builder = new StrictMode.VmPolicy.Builder(); 
StrictMode.setVmPolicy(builder.build());

It will ignore URI exposure.

Happy coding :-)

回答11:

Using the fileProvider is the way to go. But you can use this simple workaround:

WARNING: It will be fixed in next Android release - https://issuetracker.google.com/issues/37122890#comment4

replace:

startActivity(intent);

by

startActivity(Intent.createChooser(intent, "Your title"));

回答12:

I used Palash's answer given above but it was somewhat incomplete, I had to provide permission like this

Intent intent = new Intent(Intent.ACTION_VIEW);
    Uri uri;
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
        uri = FileProvider.getUriForFile(this, getPackageName() + ".provider", new File(path));

        List<ResolveInfo> resInfoList = getPackageManager().queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY);
        for (ResolveInfo resolveInfo : resInfoList) {
            String packageName = resolveInfo.activityInfo.packageName;
            grantUriPermission(packageName, uri, Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION);
        }
    }else {
        uri = Uri.fromFile(new File(path));
    }

    intent.setDataAndType(uri, "application/vnd.android.package-archive");

    intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

    startActivity(intent);

回答13:

Just paste the below code in activity onCreate()

StrictMode.VmPolicy.Builder builder = new StrictMode.VmPolicy.Builder(); StrictMode.setVmPolicy(builder.build());

It will ignore URI exposure

回答14:

add this two line in onCreate

StrictMode.VmPolicy.Builder builder = new StrictMode.VmPolicy.Builder();
    StrictMode.setVmPolicy(builder.build());

Share method

File dir = new File(Environment.getExternalStorageDirectory(), "ColorStory");
File imgFile = new File(dir, "0.png");
Intent sendIntent = new Intent(Intent.ACTION_VIEW);
sendIntent.setType("image/*");
sendIntent.setAction(Intent.ACTION_SEND);
sendIntent.putExtra(Intent.EXTRA_STREAM, Uri.parse("file://" + imgFile));
sendIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
startActivity(Intent.createChooser(sendIntent, "Share images..."));

回答15:

Here my solution:

in Manifest.xml

<application
            android:name=".main.MainApp"
            android:allowBackup="true"
            android:icon="@drawable/ic_app"
            android:label="@string/application_name"
            android:logo="@drawable/ic_app_logo"
            android:theme="@style/MainAppBaseTheme">

        <provider
                android:name="androidx.core.content.FileProvider"
                android:authorities="${applicationId}.provider"
                android:exported="false"
                android:grantUriPermissions="true">
            <meta-data
                    android:name="android.support.FILE_PROVIDER_PATHS"
                    android:resource="@xml/provider_paths"/>
        </provider>

in res/xml/provider_paths.xml

   <?xml version="1.0" encoding="utf-8"?>
    <paths xmlns:android="http://schemas.android.com/apk/res/android">
        <external-path name="external_files" path="."/>
    </paths>

in my fragment I has the next code:

 Uri myPhotoFileUri = FileProvider.getUriForFile(getActivity(), getActivity().getApplicationContext().getPackageName() + ".provider", myPhotoFile);               
    intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
    intent.putExtra(MediaStore.EXTRA_OUTPUT, myPhotoFileUri);

Тhat's all you need.

Also not need to create

public class GenericFileProvider extends FileProvider {}

I test on Android 5.0, 6.0 and Android 9.0 and it's success work.

回答16:

For downloading pdf from server , add below code in your service class. Hope this is helpful for you.

File file = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS), fileName + ".pdf");
    intent = new Intent(Intent.ACTION_VIEW);
    //Log.e("pathOpen", file.getPath());

    Uri contentUri;
    contentUri = Uri.fromFile(file);
    intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_NEW_TASK);

    if (Build.VERSION.SDK_INT >= 24) {

        Uri apkURI = FileProvider.getUriForFile(context, context.getApplicationContext().getPackageName() + ".provider", file);
        intent.setDataAndType(apkURI, "application/pdf");
        intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);

    } else {

        intent.setDataAndType(contentUri, "application/pdf");
    }

And yes , don't forget to add permissions and provider in your manifest.

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

<application

<provider
        android:name="android.support.v4.content.FileProvider"
        android:authorities="${applicationId}.provider"
        android:exported="false"
        android:grantUriPermissions="true">
        <meta-data
            android:name="android.support.FILE_PROVIDER_PATHS"
            android:resource="@xml/provider_paths" />
    </provider>

</application>

回答17:

I don't know why, I did everything exactly the same as Pkosta (https://stackoverflow.com/a/38858040 ) but kept getting error:

java.lang.SecurityException: Permission Denial: opening provider redacted from ProcessRecord{redacted} (redacted) that is not exported from uid redacted

I wasted hours on this issue. The culprit? Kotlin.

val playIntent = Intent(Intent.ACTION_VIEW, uri)
intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)

intent was actually setting getIntent().addFlags instead of operating on my newly declared playIntent.

回答18:

i put this method so imageuri path easily get in content.

enter code here
public Uri getImageUri(Context context, Bitmap inImage)
{
    ByteArrayOutputStream bytes = new ByteArrayOutputStream();
    inImage.compress(Bitmap.CompressFormat.PNG, 100, bytes);
    String path = MediaStore.Images.Media.insertImage(context.getContentResolver(), 
    inImage, "Title", null);
    return Uri.parse(path);
}

回答19:

I know this is a pretty old question but this answer is for future viewers. So I've encountered a similar problem and after researching, I've found an alternative to this approach.

Your Intent here for eg: To view your image from your path in Kotlin

 val intent = Intent()
 intent.setAction(Intent.ACTION_VIEW)
 val file = File(currentUri)
 intent.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
 val contentURI = getContentUri(context!!, file.absolutePath)
 intent.setDataAndType(contentURI,"image/*")
 startActivity(intent)

Main Function below

private fun getContentUri(context:Context, absPath:String):Uri? {
        val cursor = context.getContentResolver().query(
            MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
            arrayOf<String>(MediaStore.Images.Media._ID),
            MediaStore.Images.Media.DATA + "=? ",
            arrayOf<String>(absPath), null)
        if (cursor != null && cursor.moveToFirst())
        {
            val id = cursor.getInt(cursor.getColumnIndex(MediaStore.MediaColumns._ID))
            return Uri.withAppendedPath(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, Integer.toString(id))
        }
        else if (!absPath.isEmpty())
        {
            val values = ContentValues()
            values.put(MediaStore.Images.Media.DATA, absPath)
            return context.getContentResolver().insert(
                MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values)
        }
        else
        {
            return null
        }
    }

Likewise, instead of an image, you can use any other file format like pdf and in my case, it worked just fine

回答20:

https://stackoverflow.com/a/38858040/395097 this answer is complete.

This answer is for - you already have an app which was targeting below 24, and now you are upgrading to targetSDKVersion >= 24.

In Android N, only the file uri exposed to 3rd party app is changed. (Not the way we were using it before). So change only the places where you are sharing the path with 3rd party app (Camera in my case)

In our app we were sending uri to Camera app, in that location we are expecting the camera app to store the captured image.

1. For android N, we generate new Content:// uri based url pointing to file.
2. We generate usual File api based path for the same (using older method).

Now we have 2 different uri for same file. #1 is shared with Camera app. If the camera intent is success, we can access the image from #2.

Hope this helps.

回答21:

Xamarin.Android

Note: The path xml/provider_paths.xml (.axml) couldn't be resolved, even after making the xml folder under Resources (maybe it can be put in an existing location like Values, didn't try), so I resorted to this which works for now. Testing showed that it only needs to be called once per application run (which makes sense being that it changes the operational state of the host VM).

Note: xml needs to be capitalized, so Resources/Xml/provider_paths.xml

Java.Lang.ClassLoader cl = _this.Context.ClassLoader;
Java.Lang.Class strictMode = cl.LoadClass("android.os.StrictMode");                
System.IntPtr ptrStrictMode = JNIEnv.FindClass("android/os/StrictMode");
var method = JNIEnv.GetStaticMethodID(ptrStrictMode, "disableDeathOnFileUriExposure", "()V");                
JNIEnv.CallStaticVoidMethod(strictMode.Handle, method);

回答22:

@Pkosta 's answer is one way of doing this.

Besides using FileProvider, you can also insert the file into MediaStore (especially for image and video files), because files in MediaStore are accessible to every app:

The MediaStore is primarily aimed at video, audio and image MIME types, however beginning with Android 3.0 (API level 11) it can also store non-media types (see MediaStore.Files for more info). Files can be inserted into the MediaStore using scanFile() after which a content:// style Uri suitable for sharing is passed to the provided onScanCompleted() callback. Note that once added to the system MediaStore the content is accessible to any app on the device.

For example, you can insert a video file to MediaStore like this:

ContentValues values = new ContentValues();
values.put(MediaStore.Video.Media.DATA, videoFilePath);
Uri contentUri = context.getContentResolver().insert(
      MediaStore.Video.Media.EXTERNAL_CONTENT_URI, values);

contentUri is like content://media/external/video/media/183473, which can be passed directly to Intent.putExtra:

intent.setType("video/*");
intent.putExtra(Intent.EXTRA_STREAM, contentUri);
intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
activity.startActivity(intent);

This works for me, and save the hassles of using FileProvider.

回答23:

Simply let it ignore the URI Exposure... Add it after on create

StrictMode.VmPolicy.Builder builder = new StrictMode.VmPolicy.Builder(); StrictMode.setVmPolicy(builder.build()); 

回答24:

Try this solution

PUT THESE PERMISSIONS IN MANIFEST

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

INTENT TO CAPTURE IMAGE

Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
                    startActivityForResult(takePictureIntent, REQUEST_IMAGE_CAPTURE);
                }

GET CAPTURED IMAGE IN ONACTIVITYRESULT

@Override
            protected void onActivityResult(int requestCode, int resultCode, Intent data) {
                super.onActivityResult(requestCode, resultCode, data);
                if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
                    Bundle extras = data.getExtras();
                    Bitmap imageBitmap = (Bitmap) extras.get("data");
                    // CALL THIS METHOD TO GET THE URI FROM THE BITMAP
                    Uri tempUri = getImageUri(getApplicationContext(), imageBitmap);
                    //DO SOMETHING WITH URI
                }
            } 

METHOD TO GET IMAGE URI

public Uri getImageUri(Context inContext, Bitmap inImage) {
        ByteArrayOutputStream bytes = new ByteArrayOutputStream();
        inImage.compress(Bitmap.CompressFormat.JPEG, 100, bytes);
        String path = MediaStore.Images.Media.insertImage(inContext.getContentResolver(), inImage, "Title", null);
        return Uri.parse(path);
    }

回答25:

In my case I got rid of the exception by replacing SetDataAndType with just SetData.

来源：https://stackoverflow.com/questions/54510186/delphi-use-android-fileprovider-to-send-intent-to-open-and-image-file-with-the-d