Creating API to Retrieve Images in SUSI.AI Server

SUSI Server needed to have an API where users can upload and store images. This images will be useful in setting custom theme for the botbuilder or for chat.susi.ai. User can upload image from their systems instead of pasting the link of an image stored in cloud. Also we need an API to retrieve the stored image given its full path. This blog explains how the SUSI Server returns the image stored upon requesting.

Understanding where the image is stored

The images uploaded to the SUSI Server is stored in its local storage. The local storage is where all the json files and other data are stored. We store the images inside “image_uploads” folder. In the get image API, the client will provide the full path of the image i.e the user UUID and the image’s full name. Then we need to fetch this image from the local storage and return it.

Retrieving the image from local storage

The Retrieving image API has the endpoint “/cms/getImage.png”. The servlet file is “GetImageServlet.java”. The client has to send the full path of the image in the parameter “image”. A sample GET request is “http://127.0.0.1:4000/cms/getImage.png?image=963e84467b92c0916b27d157b1d45328/1529692996805_susi icon.png”.

We need to retrieve the given image from the correct path.

Query post = RemoteAccess.evaluate(request);
String image_path = post.get("image","");
File imageFile = new File(DAO.data_dir  + File.separator + "image_uploads" + File.separator+ image_path);
if (!imageFile.exists()) {response.sendError(503, "image does not exist"); return;}
String file = image_path.substring(image_path.indexOf("/")+1);

 

Writing the image in Byte Stream

Now that we have the image file, we need to write that image in a Byte array output stream. We read the pixels data from the image using “FileInputStream” method.

ByteArrayOutputStream data = new ByteArrayOutputStream();
byte[] b = new byte[2048];
InputStream is = new BufferedInputStream(new FileInputStream(imageFile));
int c;
try {
while ((c = is.read(b)) >  0) {data.write(b, 0, c);}
} catch (IOException e) {}

 

Returning the image to the client

Now that we have the image data in the Byte array, we can send that data to the client. Before that we have to set the response type. We set the response type accordingly if the image is png, gif, or jpg. For other types, we the response type as “octet-stream”. Finally we attach the image in the response object and send it.

if (file.endsWith(".png") || (file.length() == 0 && request.getServletPath().endsWith(".png"))) post.setResponse(response, "image/png");
else if (file.endsWith(".gif") || (file.length() == 0 && request.getServletPath().endsWith(".gif"))) post.setResponse(response, "image/gif");
else if (file.endsWith(".jpg") || file.endsWith(".jpeg") || (file.length() == 0 && request.getServletPath().endsWith(".jpg"))) post.setResponse(response, "image/jpeg");
else post.setResponse(response, "application/octet-stream");

ServletOutputStream sos = response.getOutputStream();
sos.write(data.toByteArray());
post.finalize();

 

Result:

Resources

 

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Creating API to Upload Images in SUSI.AI Server

SUSI Server needed to have an API where users can upload and store images. This images will be useful in setting custom theme for the botbuilder or for chat.susi.ai. User can upload image from their systems instead of pasting the link of an image stored in cloud. This blog explains how the SUSI Server stores the images in its local storage.

Creating Upload Image Service

UploadImageService.java is the file which creates the API to upload image. After creating the UploadImageService class in this file, we need to include the class in SusiServer.java to enable the API:

// add services
  services = new Class[]{
...
UploadImageService.class

Restricting access rights and giving API endpoint name

The Upload Image API should be available only to logged in users and not to anonymous users. Therefore we need to set the base user role to “USER”.  Also we need to set the name of the API endpoint. Lets set it to “/cms/uploadImage.json”.

@Override
public UserRole getMinimalUserRole() {
return UserRole.USER;
}

@Override
public String getAPIPath() {
return "/cms/uploadImage.json";
}

 

Creating API to accept the Post request

We need to accept the image uploaded by the client in a post request. The post request will contain the following parameters:

  • access_token – used to verify identity of the user and get their UUID
  • image_name – the name of the image
  • image (the image file) – the actual image file

To accept the post request on this route, we define the following function:

@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
resp.setHeader("Access-Control-Allow-Origin", "*"); // enable CORS
JSONObject json = new JSONObject();
Part imagePart = req.getPart("image");
if (req.getParameter("access_token") != null) {
if (imagePart == null) {
json.put("accepted", false);
json.put("message", "Image not given");
} else {
// save image

 

Getting the correct storage location

We are saving the image in the local storage of the server, i.e inside the “data” folder. Inside it, we store inside the “image_uploads” folder. The image path and name has three parts:

  • User’s UUID as the sub folder’s name
  • System time in milliseconds as the first part of the image’s name
  • The image’s name given by the user as the second part of the image’s name

String image_name = req.getParameter("image_name");
ClientCredential credential = new ClientCredential(ClientCredential.Type.access_token, req.getParameter("access_token"));
Authentication authentication = DAO.getAuthentication(credential);
ClientIdentity identity = authentication.getIdentity();
String userId = identity.getUuid();
String imagePath = DAO.data_dir  + File.separator + "image_uploads" + File.separator + userId;

 

Saving the image

After we have formed the location of the image to be stored, we need to actually write that file to the local storage. Here is the code snippet which does that:

// Reading content for image
Image image = ImageIO.read(imagePartContent);
BufferedImage bi = this.toBufferedImage(image);
// Checks if images directory exists or not. If not then create one
if (!Files.exists(Paths.get(imagePath))) new File(imagePath).mkdirs();
String new_image_name = System.currentTimeMillis() + "_" + image_name;
File p = new File(imagePath + File.separator + new_image_name);
if (p.exists()) p.delete();
ImageIO.write(bi, "jpg", new File(imagePath + File.separator + new_image_name));

 

Thus the image gets stored in the local storage inside of the folder named by user’s UUID

Here, the number 963e84467b92c0916b27d157b1d45328 is the user UUID of the user and 1529692996805 is generated by getting the System time in milliseconds. This helps to differentiate between images of same name uploaded by the same user.

Resources

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Adding Support for Displaying Images in SUSI iOS

SUSI provided exciting features in the chat screen. The user can ask a different type of queries and SUSI respond according to the user query. If the user wants to get news, the user can just ask news and SUSI respond with the news. Like news, SUSI can respond to so many queries. Even user can ask SUSI for the image of anything. In response, SUSI displays the image that the user asked. Exciting? Let’s see how displaying images in the chat screen of SUSI iOS is implemented.

Getting image URL from server side –

When we ask susi for the image of anything, it returns the URL of image source in response with answer action type. We get the URL of the image in the expression key of actions object as below:

actions:
[
{
language: "en",
type: "answer",
expression:
"https://pixabay.com/get/e835b60f2cf6033ed1584d05fb1d4790e076e7d610ac104496f1c279a0e8b0ba_640.jpg"
}
]

 

Implementation in App –

In the app, we check if the response coming from server is image URL or not by following two methods.

One – Check if the expression is a valid URL:

func isValidURL() -> Bool {
if let url = URL(string: self) {
return UIApplication.shared.canOpenURL(url)
}
return false
}

The method above return boolean value if the expression is valid or not.

Two – Check if the expression contains image source in URL:

func isImage() -> Bool {
let imageFormats = ["jpg", "jpeg", "png", "gif"]

if let ext = self.getExtension() {
return imageFormats.contains(ext)
}

return false
}

The method above returns the boolean value if the URL string is image source of not by checking its extension.

If both the methods return true, the expression is a valid URL and contain image source, then we consider it as an Image and proceed further.

In collectionView of the chat screen, we register ImageCell and present the cell if the response is the image as below.

Registering the Cell –

register(_:forCellWithReuseIdentifier:) method registers a class for use in creating new collection view cells.

collectionView?.register(ImageCell.self, forCellWithReuseIdentifier: ControllerConstants.imageCell)

Presenting the Cell using cellForItemAt method of UICollectionView

The implementation of cellForItemAt method is responsible for creating, configuring, and returning the appropriate cell for the given item. We do this by calling the dequeueReusableCell(withReuseIdentifier:for:) method of the collection view and passing the reuse identifier that corresponds to the cell type we want. That method always returns a valid cell object. Upon receiving the cell, we set any properties that correspond to the data of the corresponding item, perform any additional needed configuration, and return the cell.

if let expression = message.answerData?.expression, expression.isValidURL(), expression.isImage() {
if let cell = collectionView.dequeueReusableCell(withReuseIdentifier: ControllerConstants.imageCell, for: indexPath) as? ImageCell {
cell.message = message
return cell
}
}

In ImageCell, we present a UIImageView that display the image. When cell the message var, it call downloadImage method to catch and display image from server URL using Kingfisher method.

In method below –

  1. Get image URL string and check if it is image URL
  2. Convert image string to image URL
  3. Set image to the imageView
func downloadImage() {
if let imageString = message?.answerData?.expression, imageString.isImage() {
if let url = URL(string: imageString) {
imageView.kf.setImage(with: url, placeholder: ControllerConstants.Images.placeholder, options: nil, progressBlock: nil, completionHandler: nil)
}
}
}

We have added a tap gesture to the imageView so that when the user taps the image, it opens the full image in the browser by using the method below:

@objc func openImage() {
if let imageURL = message?.answerData?.expression {
if let url = URL(string: imageURL) {
UIApplication.shared.open(url, options: [:], completionHandler: nil)
}
}
}

 

Final Output –

Resources –

  1. Apple’s Documentations on collectionView(_:cellForItemAt:) method
  2. Apple’s Documentations on register(_:forCellWithReuseIdentifier:) method
  3. SUSI iOS Link: https://github.com/fossasia/susi_iOS
  4. SUSI API Link: http://api.susi.ai/
  5. Kingfisher – A lightweight, pure-Swift library for downloading and caching images from the web
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Creating Sajuno Filter in Editor of Phimpme Android

What is Sajuno filter?

Sajuno filter is an image filter which we used in the editor of Phimpme Android application for brightening the skin region of a portrait photo.

How to perform?

Generally in a portrait photo, the dark regions formed due to shadows or low lightning conditions or even due to tanning of skin contains more darker reds than the greens and blues. So, for fixing this darkness of picture, we need to find out the area where reds are more dominant than the greens and blues. After finding the region of interest, we need to brighten that area corresponding to the difference of the reds and other colors.

How we implemented in Phimpme Android?

In Phimpme Android application, first we created a mask satisfying the above conditions. It can be created by subtracting blues and greens from red. The intensity can be varied by adjusting the intensity of reds. The condition mentioned here in programmatical way is shown below.


bright = saturate_cast<uchar>((intensity * r - g * 0.4 - b * 0.4));

In the above statement, r,g,b are the reds, greens and blues of the pixels respectively. The coefficients can be tweaked a little. But these are the values which we used in Phimpme Android application. After the above operation, a mask is generated as below.

 

This mask has the values that correspond to the difference of reds and greens and difference of reds and blues. So, we used this mask directly to increase the brightness of the dark toned skin of the original image. We simply need to add the mask and the original image. This results the required output image shown below.

 

As you can see the resultant image has less darker shades on the face than the original image. The way of implementation which we used in Phimpme Android editor is shown below.


double intensity = 0.5 + 0.35 * val;     // 0 < val < 1
dst = Mat::zeros(src.size(), src.type());
uchar r, g, b;
int bright;

for (y = 0; y < src.rows; y++) {
   for (x = 0; x < src.cols; x++) {
       r = src.at<Vec3b>(y, x)[0];
       g = src.at<Vec3b>(y, x)[1];
       b = src.at<Vec3b>(y, x)[2];

       bright = saturate_cast<uchar>((intensity * r - g * 0.4 - b * 0.4));
       dst.at<Vec3b>(y, x)[0] =
               saturate_cast<uchar>(r + bright);
       dst.at<Vec3b>(y, x)[1] =
               saturate_cast<uchar>(g + bright);
       dst.at<Vec3b>(y, x)[2] =
               saturate_cast<uchar>(b + bright);
   }
}

Resources:

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Handle Large Size Images in Phimpme

Phimpme is an image app which provides custom camera, sharing features along with a well-featured gallery section. In gallery, it allows users to view local images. Right now we are using Glide to load images in the gallery, it is working fine for small size images it lags a bit when it comes to handling the high quality large images in the app. So in this post, I will explaining how to handle large size  images without lagging or without taking much time. To solve this problem I am using android universal image loader library which is very light when compared to glide.

Step – 1

First step is to include the dependency in the phimpme project and it can be done by the following way

dependencies {
compile 'com.nostra13.universalimageloader:universal-image-loader:1.9.4'
}

Step-2

After this create an Android universal image loader instance. We can create imageloader instance in our application class if we want to use the image loader globally.

ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(
       this).memoryCacheExtraOptions(480, 800).defaultDisplayImageOptions(defaultOptions)
       .diskCacheExtraOptions(480, 800, null).threadPoolSize(3)
       .threadPriority(Thread.NORM_PRIORITY - 2)
       .tasksProcessingOrder(QueueProcessingType.FIFO)
       .denyCacheImageMultipleSizesInMemory()
       .memoryCache(new LruMemoryCache(MAXMEMONRY / 5))
       .diskCache(new UnlimitedDiskCache(cacheDir))
       .diskCacheFileNameGenerator(new HashCodeFileNameGenerator()) // default
       .imageDownloader(new BaseImageDownloader(this)) // default
       .imageDecoder(new BaseImageDecoder(false)) // default
       .defaultDisplayImageOptions(DisplayImageOptions.createSimple()).build();
 
 this.imageLoader = ImageLoader.getInstance();
 imageLoader.init(config);

Add the above code in the application class.


Step-3

Now our image loader instance is created now we can load an image easily. But to avoid the out of memory error and large image size error we can set many options to an image loader. In options we can set maximum memory allowed to image loader, maximum resolution and set particular architecture, it can be done in following ways.


Step-4

File cacheDir = com.nostra13.universalimageloader.utils.StorageUtils.getCacheDirectory(this);
 int MAXMEMONRY = (int) (Runtime.getRuntime().maxMemory());

To load an image using universal image loader just pass the URI of an image and to load write the below code.
Now the time is to load an image from local storage. We can load images from local storage, drawable, assets easily.

ImageLoader imageLoader = ((MyApplication)getApplicationContext()).getImageLoader();
 imageLoader.displayImage(imageUri, imageView);

This is how I handled large size image in Phimpme.

Large Image in Phimpme


References :

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Uploading Images to SUSI Server

SUSI Skill CMS is a web app to create and modify SUSI Skills. It needs API Endpoints to function and SUSI Server makes it possible. In this blogpost, we will see how to add a servlet to SUSI Server to upload images and files.

The CreateSkillService.java file is the servlet which handles the process of creating new Skills. It requires different user roles to be implemented and hence it extends the AbstractAPIHandler.

Image upload is only possible via a POST request so we will first override the doPost method in this servlet.

  @Override
  protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  resp.setHeader("Access-Control-Allow-Origin", "*"); // enable CORS

resp.setHeader enables the CORS for the servlet. This is required as POST requests must have CORS enables from the server. This is an important security feature that is provided by the browser.

        Part file = req.getPart("image");
        if (file == null) {
            json.put("accepted", false);
            json.put("message", "Image not given");
        }

Image upload to servers is usually a Multipart Request. So we get the part which is named as “image” in the form data.

When we receive the image file, then we check if the image with the same name exists on the server or not.

Path p = Paths.get(language + File.separator + “images/” + image_name);

        if (image_name == null || Files.exists(p)) {
                json.put("accepted", false);
                json.put("message", "The Image name not given or Image with same name is already present ");
            }

If the same file is present on the server then we return an error to the user requesting to give a unique filename to upload.

Image image = ImageIO.read(filecontent);
BufferedImage bi = this.createResizedCopy(image, 512, 512, true);
if(!Files.exists(Paths.get(language.getPath() + File.separator + "images"))){
   new File(language.getPath() + File.separator + "images").mkdirs();
           }
ImageIO.write(bi, "jpg", new File(language.getPath() + File.separator + "images/" + image_name));

Then we read the content for the image in an Image object. Then we check if images directory exists or not. If there is no image directory in the skill path specified then create a folder named “images”.

We usually prefer square images at the Skill CMS. So we create a resized copy of the image of 512×512 dimensions and save that copy to the directory we created above.

BufferedImage createResizedCopy(Image originalImage, int scaledWidth, int scaledHeight, boolean preserveAlpha) {
        int imageType = preserveAlpha ? BufferedImage.TYPE_INT_RGB : BufferedImage.TYPE_INT_ARGB;
        BufferedImage scaledBI = new BufferedImage(scaledWidth, scaledHeight, imageType);
        Graphics2D g = scaledBI.createGraphics();
        if (preserveAlpha) {
            g.setComposite(AlphaComposite.Src);
        }
        g.drawImage(originalImage, 0, 0, scaledWidth, scaledHeight, null);
        g.dispose();
        return scaledBI;
    }

The function above is used to create a  resized copy of the image of specified dimensions. If the image was a PNG then it also preserves the transparency of the image while creating a copy.

Since the SUSI server follows an API centric approach, all servlets respond in JSON.

       resp.setContentType("application/json");
       resp.setCharacterEncoding("UTF-8");
       resp.getWriter().write(json.toString());’

At last, we set the character encoding and the character set of the output. This helps the clients to parse the data easily.

To see this endpoint in live send a POST request at http://api.susi.ai/cms/createSkill.json.

Resources

Apache Docs: https://commons.apache.org/proper/commons-fileupload/using.html

Multipart POST Request Tutorial: http://www.codejava.net/java-se/networking/upload-files-by-sending-multipart-request-programmatically

Java File Upload tutorial: https://ursaj.com/upload-files-in-java-with-servlet-api

Jetty Project: https://github.com/jetty-project/

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Displaying an Animated Image in Splash Screen of Phimpme Android

A splash screen is the welcome page of the application. It gives the first impression of the application to the user. So, it is very important to make this page a better-looking one. In Phimpme Android, we had a normal page with a static image which is very common in all applications. So, in order to make it different from the most applications, we created an animation of the logo and added it to the splash screen.

As the splash screen is the first page/activity of the Phimpme Android application, most of the initialization functions are called in this activity. These initializations might take a little time giving us the time to display the logo animation.

Creating the animation of the Phimpme logo

For creating the animation of the Phimpme Android application’s logo, we used Adobe After Effects software. There are many free tools available on the web for creating the animation but due to the sophistic features present in After Effects, we used that software. We created the Phimpme Android application’s logo animation like any other normal video but with a lower frame rate. We used 12 FPS for the animation and it was fine as it was for a logo. Finally, we exported the animation as a transparent PNG formatted image sequence.

How to display the animation?

In Phimpme Android, we could’ve directly used the sequence of resultant images for displaying the animation. We could’ve done that by using a handler to change the image resource of an imageview. But this approach is very crude. So, we planned to create a GIF with the image sequence first and then display the GIF in the image view.

Creating a GIF from the image sequence

There are many tools on the web which create a GIF image from the given image sequence but most of the tools don’t support transparent images. This tool which we used to create the transparent GIF image supports both transparent and normal images. The frame rate and loop count can also be adjusted using this free tool. Below is the GIF image created using that tool.

Displaying the GIF in Phimpme

GIF image can be displayed in Phimpme Android application very easily using the famous Glide image caching and displaying library. But glide library doesn’t fulfill the need of the current scenario. Here, in Phimpme Android, we are displaying the GIF in the splash screen i.e. the next page should get displayed automatically. As we are showing an intro animation, the next activity/page should get opened only after the animation is completed. For achieving this we need a listener which triggers on the loop completion of the GIF image. Glide doesn’t provide any listener of this kind so we cannot Glide here.

There is a library named android-gif-drawable, which has the support for a GIF completion listener and many other methods. So, we used this for displaying the Phimpme Android application’s logo animation GIF image in the splash screen. When the GIF completed function gets triggered, we started the next activity if all the tasks which had to get completed in this activity itself are finished. Otherwise, we added a flag that the animation is done so that when the task gets completed, it just navigates to next page.

The way of the implementation described above is performed in Phimpme Android in the following manner.

First of all, we imported the library by adding it to the dependencies of build.gradle file.

compile 'pl.droidsonroids.gif:android-gif-drawable:1.2.7'

Then we added a normal imageview widget in the layout of the SplashScreen activity.

<ImageView
   android:id="@+id/imgLogo"
   android:layout_width="match_parent"
   android:layout_height="wrap_content"
   android:scaleType="fitCenter"
   android:layout_centerInParent="true"
   />

Finally, in the SplashScreen.java, we created a GifDrawable object using the GIF image of Phimpme Android logo animation, which we copied in the assets folder of the Phimpme application. We added a listener to the GifDrawble and added function calls inside that function. It is shown below.

GifDrawable gifDrawable = null;
try {
   gifDrawable = new GifDrawable( getAssets(), "splash_logo_anim.gif" );
} catch (IOException e) {
   e.printStackTrace();
}
if (gifDrawable != null) {
   gifDrawable.addAnimationListener(new AnimationListener() {
       @Override
       public void onAnimationCompleted(int loopNumber) {
           Log.d("splashscreen","Gif animation completed");
           if (can_be_finished && nextIntent != null){
               startActivity(nextIntent);
               finish();
           }else {
               can_be_finished = true;
           }
       }
   });
}
logoView.setImageDrawable(gifDrawable);

Resources:

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Binding Images Dynamically in Open Event Orga App

In Open Event Orga App (Github Repo), we used Picasso to load images from URLs and display in ImageViews. Picasso is easy to use, lightweight, and extremely configurable but there has been no new release of the library since 2015. We were using Picasso in binding adapters in order to dynamically load images using POJO properties in the layout XML itself using Android Data Binding. But this configuration was a little buggy.

The first time the app was opened, Picasso fetched the image but it was not applied to the ImageView. When the device was rotated or the activity was resumed, it loaded just fine. This was a critical issue and we tried many things to fix it but none of it quite fit our needs. We considered moving on to other Image Loading libraries like Glide, etc but it was too heavy on the size and functionality for our needs. The last resort was to update the library to develop version using Sonatype’s snapshots Repository. Now, the Picasso v2.6.0-SNAPSHOT is very stable but not released to the maven central repository, and a newer develop version v3.0.0-SNAPSHOT was launched too. So we figured we should use that. This blog will outline the steps to include the develop version of Picasso, configuring it for our needs and making it work with Android Data Binding.

Setting up Dependencies

Firstly, we need to include the sonatype repository in the repositories block of our app/build.gradle

repositories {
   ...
   maven { url 'https://oss.sonatype.org/content/repositories/snapshots/' }
}

 

Then we need to replace the Picasso dependency entry to this:

compile 'com.squareup.picasso:picasso:3.0.0-SNAPSHOT'

 

Note that if you used Jake Wharton’s OkHttp3 Downloader for Picasso, you won’t need it now, so you need to remove it from the dependency block

And you need to use this to import the downloader

import com.squareup.picasso.OkHttp3Downloader;

 

Next, we set up our Picasso DI this way

Picasso providesPicasso(Context context, OkHttpClient client) {
   Picasso picasso = new Picasso.Builder(context)
       .downloader(new OkHttp3Downloader(client))
       .build();
   picasso.setLoggingEnabled(true);
   return picasso;
}

 

Set the singleton instance in our application:

Picasso.setSingletonInstance(picasso);

 

And we are ready to use it.

Creating Adapters

Circular Image Adapter

We show event logos as circular images, so we needed to create a binding adapter for that:

@BindingAdapter("circleImageUrl")
public static void bindCircularImage(ImageView imageView, String url) {
   if(TextUtils.isEmpty(url)) {
       imageView.setImageResource(R.drawable.ic_photo_shutter);
       return;
   }

   Picasso.with()
       .load(Uri.parse(url))
       .error(R.drawable.ic_photo_shutter)
       .placeholder(R.drawable.ic_photo_shutter)
       .transform(new CircleTransform())
       .tag(MainActivity.class)
       .into(imageView);
}

 

If the URL is empty, we just show the default photo, and otherwise we load the image into the view using standard CircleTransform

Note that there is no context argument in the with method. This was implemented in Picasso recently where they removed the need for context for loading images. Now, they use a Dummy ContentProvider to get application context, which is inspired by how Firebase does it.

Now, we can just normally use this binding in layout to load the event thumbnail like this

<ImageView
   android:layout_width="@dimen/image_small"
   android:layout_height="@dimen/image_small"
   android:contentDescription="@string/event_thumbnail"
   app:circleImageUrl="@{event.thumbnailImageUrl}" />

 

This gives us a layout like this:

Next we need to load the header image with a deafult image.

Default Image Adapter

For this, we write a very simple adapter without CircleTransform

@BindingAdapter(value = { "imageUrl", "placeholder" }, requireAll = false)
public static void bindDefaultImage(ImageView imageView, String url, Drawable drawable) {
   if(TextUtils.isEmpty(url)) {
       if (drawable != null)
           imageView.setImageDrawable(drawable);
       return;
   }

   RequestCreator requestCreator = Picasso.with().load(Uri.parse(url));

   if (drawable != null) {
       requestCreator
           .placeholder(drawable)
           .error(drawable);
   }

   requestCreator
       .tag(MainActivity.class)
       .into(imageView);
}

 

As imageUrl or placeholder can be null, we check for both, and setting correct images if they are not. We use this in our header layout with both the url and default image we need to show:

<ImageView
   android:scaleType="centerCrop"
   app:imageUrl="@{ event.largeImageUrl }"
   app:placeholder="@{ @drawable/header }"
   android:contentDescription="@string/event_background" />

 

And this gives us a nice dynamic header like this:

This wraps up the blog on Picasso’s latest develop version and Binding Adapters. If you want to know more about Picasso and Android Data Binding, check these links:

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Aligning Images to Same Height Maintaining Ratio in Susper

In this blog, I’ll be sharing the idea how we have perfectly aligned images to the same height in Susper without disturbing their ratio. When it comes to aligning images perfectly, they should have:

  • Same height.
  • A proper ratio to maintain the image quality. Many developers apply same width and height without keeping in mind about image ratio which results in:
    • Blurred image,
    • Image with a lot of pixels,
    • Cropping of an image.

Earlier Susper was having image layout like this:

In the screenshot, images are not properly aligned.  They are also not having the same height. We wanted to improve the layout of images just like market leaders Google and DuckDuckGo.

  • How we implemented a better layout for images?

<div class=“container”>
  <div class=“grid” *ngIf=“Display(‘images’)”>
    <div class=“cell” *ngFor=“let item of item$ | async”>
      <a class=“image-pointer” href=“{{item.link}}”>
        <img class=“responsive-image” src=“{{item.link}}”></a>
    </div>
  </div>
</div>
I have created a container, in which images will be loaded from yacy server. Then I have created a grid with an equal number of rows and column. I have adjusted the height and width of rows and columns to obtain a grid which contains each division as a cell. The image will load inside the cell. Each cell consists of one image.
.grid {
  paddingleft: 80px;
}
.container {
  width: 100%;
  margin: 0;
  top: 0;
  bottom: 0;
  padding: 0;
}

After implementing it, we were facing issues like cropping of the image inside a cell. So, to avoid cropping and maintain the image ratio we introduced .responsive-image class which will avoid cropping of images inside cell.

.responsiveimage {
  maxwidth: 100%;
  height: 200px;
  paddingtop: 20px;
  padding: 0.6%;
  display: inlineblock;
  float: left;
}

This is how Susper’s image section looks now:

It took some time to align images, but somehow we succeeded in creating a perfect layout for the images.

We are facing some issues regarding images. Some of them don’t appear due to broken link. This issue will be resolved soon on the server.

Resources

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Share Images on Pinterest from Phimpme Android Application

After successfully establishing Pinterest authentication in Phimpme our next goal was to share the image on the Pinterest website directly from Phimpme, without using any native Android application.

Adding Pinterest Sharing option in Sharing Activity in Phimpme

To add various sharing options in Sharing Activity in the Phimpme project, I have applied a ScrollView for the list of the different sharing options which include: Facebook, Twitter, Pinterest, Imgur, Flickr and Instagram. All the App icons with the name are arranged in a TableLayout in the activity_share.xml file. Table rows consist of two columns. In this way, it is easier to add more app icons for future development.

<ScrollView
   android:layout_width="wrap_content"
   android:layout_height="@dimen/scroll_view_height"
   android:layout_above="@+id/share_done"
   android:id="@+id/bottom_view">
   <LinearLayout
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:orientation="vertical">
       <TableLayout

Adding Pinterest app icon on the icons_drawable array. This array is then used to inflate the icon on the list view.

private int[] icons_drawables = {R.drawable.ic_facebook_black, R.drawable.ic_twitter_black,R.drawable.ic_instagram_black, R.drawable.ic_wordpress_black, R.drawable.ic_pinterest_black);

Adding Pinterest text on the titles_text array. This array is then used to inflate the names of the various sharing activity.

private int[] titles_text = {R.string.facebook, R.string.twitter, R.string.instagram,
       R.string.wordpress, R.string.pinterest);

Prerequisites to share Image on Pinterest

To share an Image on Pinterest a user has to add a caption and Board ID. Our first milestone was to get the input of the Board ID  by the user. I have achieved this by taking the input in a Dialog Box. When the user clicks on the Pinterest option, a dialog box pops and then the user can add their Board ID.

private void openPinterestDialogBox() {
   AlertDialog.Builder captionDialogBuilder = new AlertDialog.Builder(SharingActivity.this, getDialogStyle());
   final EditText captionEditText = getCaptionDialog(this, captionDialogBuilder);

   captionEditText.setHint(R.string.hint_boardID);

   captionDialogBuilder.setNegativeButton(getString(R.string.cancel).toUpperCase(), null);
   captionDialogBuilder.setPositiveButton(getString(R.string.post_action).toUpperCase(), new DialogInterface.OnClickListener() {
       @Override
       public void onClick(DialogInterface dialog, int which) {
           //This should be empty it will be overwrite later
           //to avoid dismiss of the dialog on the wrong password
       }
   });

   final AlertDialog passwordDialog = captionDialogBuilder.create();
   passwordDialog.show();

   passwordDialog.getButton(AlertDialog.BUTTON_POSITIVE).setOnClickListener(new View.OnClickListener() {
       @Override
       public void onClick(View v) {
           String captionText = captionEditText.getText().toString();
           boardID =captionText;
           shareToPinterest(boardID);
           passwordDialog.dismiss();
       }
   });
}

A user can fetch the Board ID by following the steps:

Board ID is necessary because it specifies where the image needs to be posted.

Creating custom post function for Phimpme

The image is posted using a function in PDKClient class. PDKClient is found in the PDK module which we get after importing Pinterest SDK. Every image is posted on Pinterest is called a Pin. So we will call createPin function. I have made my custom createPin function so that it also accepts Bitmaps as a parameter. In the Pinterest SDK it only accepts image URL to share, The image should already be on the internet to be shared. For this reason, we to add a custom create Pin function to accept Bitmaps as an option.

public void createPin(String note, String boardId, Bitmap image, String link, PDKCallback callback) {
   if (Utils.isEmpty(note) || Utils.isEmpty(boardId) || image == null) {
       if (callback != null) callback.onFailure(new PDKException("Board Id, note, Image cannot be empty"));
       return;
   }

   HashMap<String, String> params = new HashMap<String, String>();
   params.put("board", boardId);
   params.put("note", note);
   params.put("image_base64", Utils.base64String(image));
   if (!Utils.isEmpty(link)) params.put("link", link);
   postPath(PINS, params, callback);
}

Compressing Bitmaps

Since Pinterest SDK cannot accept Bitmap I have added a function to compress the Bitmap and encode it to strings.

public static String base64String(Bitmap bitmap) {
   ByteArrayOutputStream baos = new ByteArrayOutputStream();
   bitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos);
   String b64Str = Base64.encodeToString(baos.toByteArray(), Base64.NO_WRAP);
   return b64Str;
}

Calling createPin function from the sharingActivity

From the sharingActivity we will call createPin activity. We will pass caption of the image, Board ID, Image bitmap and link(which is optional) as parameters.

PDKClient
       .getInstance().createPin(caption, boardID, image, null, new PDKCallback() {

If the image is posted successfully then onSuccess function is called which pops a snackbar and shows the success message. Otherwise, onFailure function is called which displays failure message on a snackbar.

@Override
public void onSuccess(PDKResponse response) {
   Log.d(getClass().getName(), response.getData().toString());
   Snackbar.make(parent, R.string.pinterest_post, Snackbar.LENGTH_LONG).show();
   //Toast.makeText(SharingActivity.this,message,Toast.LENGTH_SHORT).show();

}

@Override
public void onFailure(PDKException exception) {
   Log.e(getClass().getName(), exception.getDetailMessage());
   Snackbar.make(parent, R.string.Pinterest_fail, Snackbar.LENGTH_LONG).show();
   //Toast.makeText(SharingActivity.this, boardID + caption, Toast.LENGTH_SHORT).show();

}

Conclusion

In Phimpme user can now send Image on Pinterest directly from the application. This is done without the use of the native Pinterest application.

Github

Resources

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