android - FileProvider 不使用相机

Question

我正在尝试让 Camera App 将输出存储到我的内部存储中。我还了解第三方应用程序无法访问我的应用程序的内部存储但是我们可以通过 FileProvider 公开内部目录来做到这一点。我已按照此处的指南进行操作:

• Camera Intent not saving photo
• https://developer.android.com/reference/android/support/v4/content/FileProvider.html

我通过以下方式指定我的 AndroidManifest.xml:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.stackoverflow.test.camerawithfileprovider" >

    <application>
        <activity
            ...
        </activity>

        <provider
            android:name="android.support.v4.content.FileProvider"
            android:authorities="com.stackoverflow.test.camerawithfileprovider.fileprovider"
            android:exported="false"
            android:grantUriPermissions="true" >
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/file_provider_path" />
        </provider>
    </application>

</manifest>

我在/res/xml/中创建了一个名为file_provider_path.xml的xml文件:

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

这就是我创建和调用相机 Intent 的方式:

private static final int CAMERA_REQUEST_CODE = 5000;
private static final String CAMERA_FP_AUTHORITY = "com.stackoverflow.test.camerawithfileprovider.fileprovider";

Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);

Context context = MainActivity.this;
File imagePath = new File(context.getFilesDir(), "public");
if (!imagePath.exists()) imagePath.mkdirs();
File newFile = new File(imagePath, "tmp.jpg");

Uri imageUri = FileProvider.getUriForFile(context, CAMERA_FP_AUTHORITY, newFile);
//context.grantUriPermission("com.google.android.GoogleCamera", imageUri, Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION);
Log.d("YouQi", "Image URI Passing to Camera: " + imageUri.toString());

intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
startActivityForResult(intent, CAMERA_REQUEST_CODE);

当我运行应用程序时，我可以得到以下 Logcat 结果:

    11-11 20:07:39.581 18303-18303/com.stackoverflow.test.camerawithfileprovider D/YouQi: Image URI Passing to Camera: content://com.stackoverflow.test.camerawithfileprovider.fileprovider/image_capture/tmp.jpg

就在相机关闭的那一刻，我遇到了以下异常:

com.google.android.GoogleCamera E/AndroidRuntime: FATAL EXCEPTION: main
com.google.android.GoogleCamera E/AndroidRuntime: Process: com.google.android.GoogleCamera, PID: 19420
com.google.android.GoogleCamera E/AndroidRuntime: java.lang.SecurityException: Permission Denial: opening provider android.support.v4.content.FileProvider from ProcessRecord{42e44f70 19420:com.google.android.GoogleCamera/u0a83} (pid=19420, uid=10083) that is not exported from uid 10312
com.google.android.GoogleCamera E/AndroidRuntime:     at android.os.Parcel.readException(Parcel.java:1465)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.os.Parcel.readException(Parcel.java:1419)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.app.ActivityManagerProxy.getContentProvider(ActivityManagerNative.java:2882)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.app.ActivityThread.acquireProvider(ActivityThread.java:4544)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.app.ContextImpl$ApplicationContentResolver.acquireUnstableProvider(ContextImpl.java:2274)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.content.ContentResolver.acquireUnstableProvider(ContentResolver.java:1425)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.content.ContentResolver.openAssetFileDescriptor(ContentResolver.java:906)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.content.ContentResolver.openOutputStream(ContentResolver.java:669)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.content.ContentResolver.openOutputStream(ContentResolver.java:645)
com.google.android.GoogleCamera E/AndroidRuntime:     at com.android.camera.PhotoModule.onCaptureDone(PhotoModule.java:1281)
com.google.android.GoogleCamera E/AndroidRuntime:     at com.android.camera.PhotoModule$8.onClick(PhotoModule.java:593)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.view.View.performClick(View.java:4445)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.view.View$PerformClick.run(View.java:18446)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.os.Handler.handleCallback(Handler.java:733)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:95)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.os.Looper.loop(Looper.java:136)
com.google.android.GoogleCamera E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:5146)
com.google.android.GoogleCamera E/AndroidRuntime:     at java.lang.reflect.Method.invokeNative(Native Method)
com.google.android.GoogleCamera E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:515)
com.google.android.GoogleCamera E/AndroidRuntime:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:732)
com.google.android.GoogleCamera E/AndroidRuntime:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:566)
com.google.android.GoogleCamera E/AndroidRuntime:     at dalvik.system.NativeStart.main(Native Method)

谁能帮忙解释一下为什么会出现这个问题？我已经为我的问题创建了一个示例项目:http://www.axzae.com/downloads/CameraWithFileProvider.zip

无论如何，如果我明确指定，该应用程序将运行:

context.grantUriPermission(
    "com.google.android.GoogleCamera",
    imageUri,
    Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION
);

但这仅适用于 nexus/cyanogen 设备。三星相机应用可能使用不同的包名称。

Answer 1

1. 请不要尝试像 pskink 指出的那样输入 exported="true"，您的应用会在加载时崩溃。 FileProvider 不适合在这种状态下工作。

2. 尝试了 CommonsWare 的 intent.addFlags 解决方案。不工作。可能只适用于 ACTION_SEND 类型的 Intent 。

3. 我找到了答案in this post .显然，手动授予方式是唯一的解决方案。但我们总是可以循环遍历候选包列表并授予所有这些包。

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