Ars

Мне нужно решить такую проблему: хочу, чтобы из моего приложения я мог передавать любой файл в другое приложение, которое сможет его открыть

Uri fileUri = Uri.fromFile(new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES) + "/alpha_stmoritz_train.jpg"));
Intent intent = new Intent(Intent.ACTION_SEND);
intent.putExtra(Intent.EXTRA_STREAM, fileUri);
intent.setType("image/*");
intent.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION);
startActivity(Intent.createChooser(intent, "Share Image:"));

К примеру, открыть фото в галерее. Как это сделать?

Uri fileUri = Uri.fromFile(new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES) +
                "/alpha_stmoritz_train.jpg"));
Intent intent = new Intent();
intent.setAction(Intent.ACTION_VIEW);
intent.setDataAndType(fileUri, "image/*");
intent.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION);
startActivity(intent);

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

<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>

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

String localUri = "/storage/emulated/0/Pictures/alpha_stmoritz_train.jpg"; //тут уже как хотите так и формируйте путь, хоть через Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES) + имя файла
File file = new File(localUri);        
Uri contentUri = FileProvider.getUriForFile(this, this.getApplicationContext().getPackageName() + ".provider", file);
Intent openFileIntent = new Intent(Intent.ACTION_VIEW);
openFileIntent.setDataAndTypeAndNormalize(contentUri, "image/*");
openFileIntent.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION);
startActivity(openFileIntent);

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
      ...
} else {
      ...
}

public interface APIv1 {

    @Multipart
    @POST("/api/v1/order/create")
    Call<ResponseBody> SendOrder(@PartMap Map<String, RequestBody> params);

}

RequestBody rb;
        LinkedHashMap<String, RequestBody> mp= new LinkedHashMap<>();

        rb = RequestBody.create(MediaType.parse("text/plain"), String.valueOf((int)OrderProducts.getBoxSumm()));
        mp.put("price", rb);

        rb = RequestBody.create(MediaType.parse("text/plain"), "1");
        mp.put("number_person", rb);

        rb = RequestBody.create(MediaType.parse("text/plain"), "cash");
        mp.put("payment_type", rb);

        rb = RequestBody.create(MediaType.parse("text/plain"), "yes");
        mp.put("delivery", rb);

        rb = RequestBody.create(MediaType.parse("text/plain"), this.clientname);
        mp.put("client[name]", rb);

        rb = RequestBody.create(MediaType.parse("text/plain"), this.clientphone);
        mp.put("client[phone]", rb);

        rb = RequestBody.create(MediaType.parse("text/plain"), this.clientaddress);
        mp.put("client[address]", rb);

        List<OrderProducts> orderProducts = OrderProducts.getOrderProductsNew();
        for (int i = 0; i < orderProducts.size(); i++) {
            OrderProducts p = orderProducts.get(i);

            Product product = Product.getProductById(p.productid);
            if (product != null) {

                rb = RequestBody.create(MediaType.parse("text/plain"), String.valueOf(product.extid));
                mp.put("products["+ String.valueOf(i)+"][product_id]", rb);

                rb = RequestBody.create(MediaType.parse("text/plain"), String.valueOf(p.amount));
                mp.put("products["+ String.valueOf(i)+"][amount]", rb);

            }
        }

Call<ResponseBody> call = intface.SendOrder(mp);

        call.enqueue(new Callback<ResponseBody>() {
            @Override
            public void onResponse(Call<ResponseBody> call, retrofit2.Response<ResponseBody> response) {
                Log.v("Upload", "success");
            }

            @Override
            public void onFailure(Call<ResponseBody> call, Throwable t) {
                Log.e("Upload error:", t.getMessage());
            }
        });