Camera not working/saving when using Cache Uri as

问题:

I am trying to get the full image after taking a picture from a Fragment.

If I use the Uri from the file (Uri.fromFile(file)), the camera won't exit after taking the photo and tapping on the 'ok' button (looks like can't write to the Uri or who knows what).

Using the File String, in the form of '/data/data/com.package.bla/cache/img198346262jpg', it's not working as well (The file is there, but it's empty because the camera is not saving anything on it).

What I tried so far:

• Deleting the file after creating it, as this example does. However, the file doesn't exist after the camera exits.
• Added External Storage READ permission, just in case

So I have no idea why the image is not being saved and already spent/wasted a lot of time testing and figuring why it's not working.

Fragment:

private void launchCamera() {
    Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
    File outputDir = getActivity().getCacheDir();
    File file = null;
    try {
        file = File.createTempFile("img", "jpg", outputDir);
    } catch (IOException e) {
        e.printStackTrace();
    }
    if (file != null) {
        mImageUri = Uri.fromFile(file);   //using Uri is not even exiting the camera
        //mImageUri = File.toString();    //If I use String instead of an Uri, it works better (ie, can accept camera photo)
        cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, mImageUri);
        startActivityForResult(cameraIntent, RESULT_TAKE_IMAGE);
    }
}


public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (resultCode == Activity.RESULT_OK) {
        Bitmap original = BitmapFactory.decodeFile(mImageUri.toString(), bounds);
    }
}

Edited code, mImageUri. As explained, if I use Uri I can't even accept the photo in the camera app. Using a String will let me accept the photo, though the photo is not actually saved (ie the file has 0 bytes inside it).

EXPLANATION: The problem was related to saving into the cache directory. Maybe it's a bug, I am missing a permission or the camera app just can't save into your application private data directory. Adding Permission FLAG_GRANT_WRITE_URI_PERMISSION didn't solve it. Related posts: Store image from camera into private app cache directory AND Saving camera data to cache when launched via intent

UPDATE From Android 2.2 onwards getExternalCacheDir() method can be used instead of getCacheDir()

回答1:

Why not saving it in a new File

    final File root = new File(Environment.getExternalStorageDirectory() + File.separator + "MyDir" + File.separator);
    root.mkdirs();
    final String fname = "img_"+ System.currentTimeMillis() + ".jpg";
    final File sdImageMainDirectory = new File(root, fname);
    mImageUri = Uri.fromFile(sdImageMainDirectory);

And then pass that uri to the intent

    cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, mImageUri);

回答2:

from android 26+ Uri.fromFile will not work, you should use File provider instead.

AndroidManifest.xml

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

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

res/xml/file_paths.xml

<?xml version="1.0" encoding="utf-8"?>
<paths>
    <external-path
        name="external"
        path="." />
</paths>

finally

final Intent takeVideoIntent = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);

// output file
File path = new File(Environment.getExternalStorageDirectory(), "tmp.mp4");

// com.mydomain.fileprovider is authorities (manifest)
// getUri from file
Uri uri = FileProvider.getUriForFile(this, "com.mydomain.fileprovider", path);

takeVideoIntent.putExtra(MediaStore.EXTRA_OUTPUT, uri);
startActivityForResult(takeVideoIntent, 99);

tested on android 8.0 and 5.1.1

Update: on some device built-in camera would not support for EXTRA_OUTPUT, so if you want to work on all devices, build your own camera module.

回答3:

Try this is working like charm with me

private String selectedImagePath = "";
    final private int PICK_IMAGE = 1;
    final private int CAPTURE_IMAGE = 2;

public Uri setImageUri() {
        // Store image in dcim
        File file = new File(Environment.getExternalStorageDirectory() + "/DCIM/", "image" + new Date().getTime() + ".png");
        Uri imgUri = Uri.fromFile(file);
        this.imgPath = file.getAbsolutePath();
        return imgUri;
    }


    public String getImagePath() {
        return imgPath;
    }

btnGallery.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                Intent intent = new Intent();
                intent.setType("image/*");
                intent.setAction(Intent.ACTION_GET_CONTENT);
                startActivityForResult(Intent.createChooser(intent, ""), PICK_IMAGE);

            }
        });

        btnCapture.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                final Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                intent.putExtra(MediaStore.EXTRA_OUTPUT, setImageUri());
                startActivityForResult(intent, CAPTURE_IMAGE);
            }
        });

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (resultCode != Activity.RESULT_CANCELED) {
            if (requestCode == PICK_IMAGE) {
                selectedImagePath = getAbsolutePath(data.getData());
                imgUser.setImageBitmap(decodeFile(selectedImagePath));
            } else if (requestCode == CAPTURE_IMAGE) {
                selectedImagePath = getImagePath();
                imgUser.setImageBitmap(decodeFile(selectedImagePath));
            } else {
                super.onActivityResult(requestCode, resultCode, data);
            }
        }

    }


public Bitmap decodeFile(String path) {
        try {
            // Decode image size
            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;
            BitmapFactory.decodeFile(path, o);
            // The new size we want to scale to
            final int REQUIRED_SIZE = 70;

            // Find the correct scale value. It should be the power of 2.
            int scale = 1;
            while (o.outWidth / scale / 2 >= REQUIRED_SIZE && o.outHeight / scale / 2 >= REQUIRED_SIZE)
                scale *= 2;

            // Decode with inSampleSize
            BitmapFactory.Options o2 = new BitmapFactory.Options();
            o2.inSampleSize = scale;
            return BitmapFactory.decodeFile(path, o2);
        } catch (Throwable e) {
            e.printStackTrace();
        }
        return null;

    }

public String getAbsolutePath(Uri uri) {
        String[] projection = { MediaColumns.DATA };
        @SuppressWarnings("deprecation")
        Cursor cursor = managedQuery(uri, projection, null, null, null);
        if (cursor != null) {
            int column_index = cursor.getColumnIndexOrThrow(MediaColumns.DATA);
            cursor.moveToFirst();
            return cursor.getString(column_index);
        } else
            return null;
    }