android - 在 Android Nougat 上拍摄照片后，BitmapFactory 无法从 Uri 解码位图

Question

我尝试拍照，然后使用照片。这是我所做的。

我的设备是 Nexus 6P (Android 7.1.1)。

首先，我创建了一个Uri:

Uri mPicPath = UriUtil.fromFile(this, UriUtil.createTmpFileForPic());
//Uri mPicPath = UriUtil.fromFile(this, UriUtil.createFileForPic());

然后，我开始Intent:

Intent intent = ActivityUtils.getTakePicIntent(mPicPath);
if (intent.resolveActivity(getPackageManager()) != null) {
    startActivityForResult(intent, RequestCode.TAKE_PIC);
}

最后，我在 onActivityResult 上处理了这个 Uri:

if (requestCode == RequestCode.TAKE_PIC) {
    if (resultCode == RESULT_OK && mPicPath != null) {
        Bitmap requireBitmap = BitmapFactory.decodeFile(mPicPath.getPath());
        //path is like this: /Download/Android/data/{@applicationId}/files/Pictures/JPEG_20170216_173121268719051242.jpg
        requireBitmap.recycle();//Here NPE was thrown.
    }
}

同时，这里有UriUtil:

public class UriUtil {

    public static File createFileForPic() throws IOException {
        String fileName = "JPEG_" + new SimpleDateFormat("yyyyMMdd_HHmmssSSS", Locale.getDefault()).format(new Date()) + ".jpg";
        File storageDic = SPApplication.getInstance().getExternalFilesDir(Environment.DIRECTORY_PICTURES);
        return new File(storageDic, fileName);
    }

    public static File createTmpFileForPic() throws IOException {
        String fileName = "JPEG_" + new SimpleDateFormat("yyyyMMdd_HHmmssSSS", Locale.getDefault()).format(new Date());
        File storageDic = SPApplication.getInstance().getExternalFilesDir(Environment.DIRECTORY_PICTURES);
        return File.createTempFile(fileName, ".jpg", storageDic);
    }

    public static Uri fromFile(@NonNull Context context, @NonNull File file) {
        if (context == null || file == null) {
            throw new RuntimeException("context or file can't be null");
        }
        if (ActivityUtils.requireSDKInt(Build.VERSION_CODES.N)) {
            return FileProvider.getUriForFile(context, BuildConfig.APPLICATION_ID + ".file_provider", file);
        } else {
            return Uri.fromFile(file);
        }
    }
}

和getTakePicIntent(Uri):

public static Intent getTakePicIntent(Uri mPicPath) {
    Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    intent.putExtra(MediaStore.EXTRA_OUTPUT, mPicPath);
    if (!ActivityUtils.requireSDKInt(Build.VERSION_CODES.KITKAT_WATCH)) {//in pre-KitKat devices, manually grant uri permission.
        List<ResolveInfo> resInfoList = SPApplication.getInstance().getPackageManager().queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY);
        for (ResolveInfo resolveInfo : resInfoList) {
            String packageName = resolveInfo.activityInfo.packageName;
            SPApplication.getInstance().grantUriPermission(packageName, mPicPath, Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION);
        }
    } else {
        intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
        intent.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
    }
    return intent;
}

和requireSDKInt:

public static boolean requireSDKInt(int sdkInt) {
    return Build.VERSION.SDK_INT >= sdkInt;
}

除 Android Nougat(7.x.x) 外，一切都适用于不同的 Android API。即使提供了“FileProvider”，“requireBitmap”也总是返回为“null”。

读取日志后，BitmapFactory 抛出了 FileNotFoundException。就像:

BitmapFactory: Unable to decode stream: java.io.FileNotFoundException: /Download/Android/data/{@applicationId}/files/Pictures/JPEG_20170216_1744551601425984925.jpg (No such file or directory)

看起来一切都清楚了，但我还是不明白。

怎么可能呢？显然我创建了一个 File!我该如何解决？有什么想法吗？

Answer 1

我试过你的代码。这是我的尝试示例。 https://github.com/raghunandankavi2010/SamplesAndroid/tree/master/StackOverFlowTest .

看看这个博客 https://commonsware.com/blog/2016/03/15/how-consume-content-uri.html

在博客 commonsware 中提到你不应该做 new File (mPicPath.getPath())。

相反，您应该在 onActivityResult 中使用以下内容

try {
       InputStream ims = getContentResolver().openInputStream(mPicPath);
       // just display image in imageview
       imageView.setImageBitmap(BitmapFactory.decodeStream(ims));
    } catch (FileNotFoundException e) {
            e.printStackTrace();
    }

还有xml

 <external-files-path name="external_files" path="path" />

注意:它是您拥有的内容 uri。在我的手机上，我得到如下 uri。仅在 Nexus6p 上测试。

content://com.example.raghu.stackoverflowtest.fileProvider/external_files/Pictures/JPEG_20170424_161429691143693160.jpg

有关文件提供程序的更多信息 https://developer.android.com/reference/android/support/v4/content/FileProvider.html