How to Share Image using Facebook android

Question

I am trying to share Image and Content via Facebook,but what i am trying is if user is not logged in via Facebook,and user click on Share button then first it should ask for

Answer 1

first add 
FacebookSdk.sdkInitialize(getApplicationContext());
callbackManager = CallbackManager.Factory.create();    
permissionNeeds = Arrays.asList("publish_actions");
        manager = LoginManager.getInstance();   
**on onCreate and wirte below code in send button lick event**
 send.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View view) {

                        if (isOnline()) {
                            new WebView(MainActivity.this);

                            manager.logInWithPublishPermissions(MainActivity.this, permissionNeeds);
                            manager.registerCallback(callbackManager, new FacebookCallback() {

                                @Override
                                public void onSuccess(LoginResult loginResult) {
                                    sharePhotoToFacebook();
                                }

                                @Override
                                public void onCancel() {
                                    System.out.println("onCancel");
                                }

                                @Override
                                public void onError(FacebookException exception) {

                                    exception.printStackTrace();
                                }
                            });


                            alertDialog.dismiss();
                        } else {
                            Toast.makeText(getBaseContext(), "Please check internet connection", Toast.LENGTH_SHORT).show();
                        }

                    }
                });


     private void sharePhotoToFacebook() {
            try {
                Log.i("Facebook Image", camera_pathname + "");
                Bitmap image = BitmapFactory.decodeFile(camera_pathname);
                //Bitmap image = decodeFile(camera_pathname);
                image = getResizedBitmap(image);
                //Bitmap image = BitmapFactory.decodeResource(getResources(), R.mipmap.ic_launcher);

                SharePhoto photo = new SharePhoto.Builder()
                        .setBitmap(image)
                        .setCaption(et_hashtag.getText().toString())
                        .build();

                SharePhotoContent content = new SharePhotoContent.Builder()
                        .addPhoto(photo)
                        .build();

                ShareApi.share(content, null);
                Toast.makeText(getBaseContext(), "Shared successfully", Toast.LENGTH_SHORT).show();
            } catch (Exception e) {
                e.printStackTrace();
            }

            // manager.logOut();
        }