Author: anantprsd5

The share feature in the Android application is really important for the growth of your Android application and to increase the user base. In the Phimpme Android application, we have made use of the Firebase deep link to share the application as it is the most recommended way to do it. In this tutorial, I am discussing two ways to share your Android application with the help of code snippets below. The following are:

Generate the APK and share:

Sharing the APK of the application directly can be achieved very easily but it is the least recommended way to do this. To share the APK of the application via bluetooth or other applications, we can make use of the package manager to generate the apk and pass it to the share intent to get things done smoothly. The following code snippet will be used to generate the apk and to pass it on to the share intent.

PackageManager pm = getPackageManager();
ApplicationInfo ai = pm.getApplicationInfo(getPackageName(), 0);
File srcFile = new File(ai.publicSourceDir);
Intent share = new Intent();
share.setAction(Intent.ACTION_SEND);
share.setType("application/vnd.android.package-archive");
share.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(srcFile));
startActivity(Intent.createChooser(share, "APK"));

Sharing the application’s apk directly is not the most recommended way to do it as sometimes the apk generated by the PackageManager might not install properly in another device.

Using the Firebase Deep links:

The best thing about this is that it can behave differently when clicked on different devices. For example, you have Phimpme Android application installed in your mobile phone and someone else might send you the invitation link to download it again. So when you click on the deep link, rather than opening play store or any other storage from where you can download the apk, it will open up the Phimpme Application directly.

Due to these advantages, in the Phimpme Application, we have made use of this service to share the application. In this tutorial, I will discuss on how to achieve this step by step:

Step 1:

Sign in to your google account and go the Firebase console then click on the Add project button and fill in the Project name and your country and press Create Project button to proceed.

Step 2:

Click on Add firebase to your Android application button and fill in the your Android application’s package name and the SHA-1 key. You can generate this key very easily with the help of Android studio.

For this, import and open your Android application in Android studio and then press the Gradle button at the right hand side of your screen. It will open up the screen like that mentioned in the screenshot below:

Go to app>android> and double click on the signingReport and wait for the build to complete. On successful completion of the build, the SHA-1 key will be displayed on the Gradle console below.

Step 3:

Click on the register application button below to proceed. It will provide an option to download googleServices.json file but you can skip that as it is not necessary for sharing the application.

Step 4:

Click on the Dynamic links section and add create a new dynamic link. Fill in the link to locate your application and select the behaviour of how you want the link to behave on different devices. For example, in Android if the application is installed I want to directly open the application so I have made the configuration as seen from the screenshot below:

After doing this, click on the option to Create dynamic link from below and copy the generated link.

Step 5:

After generating the URL, you can simply create a share button in your android application and can share the application with the help of code snippet provided below:

Intent sendIntent = new Intent();
sendIntent.setAction(Intent.ACTION_SEND);
sendIntent.putExtra(Intent.EXTRA_TEXT, getString(R.string.install_phimpme) + "\n "+ getString(R.string.invitation_deep_link));
sendIntent.setType("text/plain");
startActivity(sendIntent);

Now go to your String.xml and create a new String resource with name invitation_deep_link and copy the dynamic link you generated using the steps mentioned above.

Resources:

https://github.com/fossasia/phimpme-android

https://console.firebase.google.com/

https://github.com/fossasia/phimpme-android/pull/545

The Phimpme app comes with a lot of image editing functionalities. One such fascinating feature Phimpme provides is to combine two or more multiple images into one with just a button click. To do this in the Phimpme Application, long click two or more medias and click the affix button to combine them into one from the menu options. This is how two images when affixed looks like:

In this post, I will talk about how to achieve this functionality in any Android application with some code snippets. Here is the step by step tutorial on how to achieve this:

Step 1:

The first step is to reduce the bitmap of the selected images to a smaller size to avoid the OutOFMemory Exception while affixing images. As by affixing the images we will be making the images smaller, we don’t need the high quality bitmaps for it. To reduce the bitmaps use the function provided below:

private Bitmap getBitmap(String path) {

       Uri uri = Uri.fromFile(new File(path));
       InputStream in = null;
       try {
       final int IMAGE_MAX_SIZE = 1200000; // 1.2MP
       in = getContentResolver().openInputStream(uri);

       // Decode image size
       BitmapFactory.Options o = new BitmapFactory.Options();
       o.inJustDecodeBounds = true;
       BitmapFactory.decodeStream(in, null, o);
       in.close();

       int scale = 1;
           while ((o.outWidth * o.outHeight) * (1 / Math.pow(scale, 2)) >
               IMAGE_MAX_SIZE) {
                   scale++;
       }

       Bitmap bitmap = null;
       in = getContentResolver().openInputStream(uri);
       if (scale > 1) {
           scale--;
           // scale to max possible inSampleSize that still yields an image
           // larger than target
           o = new BitmapFactory.Options();
           o.inSampleSize = scale;
           bitmap = BitmapFactory.decodeStream(in, null, o);

           // resize to desired dimensions
           int height = bitmap.getHeight();
           int width = bitmap.getWidth();

           double y = Math.sqrt(IMAGE_MAX_SIZE
                   / (((double) width) / height));
           double x = (y / height) * width;

           Bitmap scaledBitmap = Bitmap.createScaledBitmap(bitmap, (int) x,
                   (int) y, true);
           bitmap.recycle();
           bitmap = scaledBitmap;

           System.gc();
       } else {
           bitmap = BitmapFactory.decodeStream(in);
       }
       in.close();

       Log.d(TAG, "bitmap size - width: " +bitmap.getWidth() + ", height: " +
               bitmap.getHeight());
       return bitmap;
   } catch (IOException e) {
       Log.e(TAG, e.getMessage(),e);
       return null;
   }
}

Step 2:

Create a bitmap array of the selected images using the following snippet:

for (int i = 0; i < selectedMedias.size(); i++) {
    bitmapArray.add(getBitmap(selectedMedias.get(i).getPath()));
}

Here the selectedMedias is the ArrayList<Media> files which is used to create a bitmap array of reduced pixels using the function getBitmap we created in the first step.

Step 3:

Create a union bitmap of the two images of particular width and height and then draw your bitmaps into a canvas using the Android Canvas class :

unionBitmap = Bitmap.createBitmap(getBitmapsWidth(bitmapArray), getMaxBitmapHeight(bitmapArray), Bitmap.Config.ARGB_8888);
Canvas comboImage = new Canvas(unionBitmap);

Step 4:

The last step is to combine the two images and get the affixed Canvas as the result. This can be done using the function given below which takes the Canvas and ArrayList of bitmaps as a parameter and returns a Canvas of images.

private static Canvas combineBitmap(Canvas cs, ArrayList bpmList){
       int width = bpmList.get(0).getWidth();
       cs.drawBitmap(bpmList.get(0), 0f, 0f, null);

       for (int i = 1; i < bpmList.size(); i++) {
           cs.drawBitmap(bpmList.get(i), width, 0f, null);
           width += bpmList.get(i).getWidth();
       }
       return cs;
   }

This is how we achieved the affixing images feature in our phimpme Android application. For the complete working source code. Refer to the Affix.java class in Phimpme Android project source code.

Resources:

1. https://developer.android.com/guide/topics/graphics/2d-graphics.html
2. https://github.com/fossasia/phimpme-android/
3. https://github.com/HoraApps/LeafPic
4. https://stackoverflow.com/questions/11740362/merge-two-bitmaps-in-android

What is Travis CI? It’s importance in Android Testing.

Travis CI is continuous integration service which is hosted online and makes it easy for developers to automate any kinds of test on their Github projects. In an open source project, there are many developers from around the world working together and the repository experiences many new commits in a single day. Their might be a chance that while making the changes, they have broken something in the application. In the first blog, I discussed how to add Espresso UI tests. After this the question arises is how to use these tests to check the stability at each push or a pull request.

How I ran Espresso Tests in Phimpme using Travis?

After adding the Espresso Tests in the application, we  need to configure .travis.yml file to run the tests on each push in the repository. This can be achieved by following the steps below:

Step 1:

In the .travis.yml file of the repository, check whether the existing configuration exists to check for gradle build of the application. Create one in case it is not their and add the configurations to do a build check. You can take help from the official site of Travis or from the .travis.yml file in the Phimpme repository.

Step 2:

Now in the before script part of the file add the following codes which will start the emulator in the Travis to run the Espresso Tests.

    Before_script:

    – echo no | android create avd —force –n test –t android–19 – –abi armeabi–v7a

    – emulator –avd test –no–audio –no–window &

     – sleep 300

     – adb shell input keyevent 82 &

The sleep 300 is used to wait for a specified time so that the emulator starts perfectly before running the test.

Step 3:

In the script part of the file, run the Espresso test written in the application by adding the following line of codes.

Script:

./gradlew connectedAndroidTest

After adding these, make a test commit on your repository. Login to your Travis account to check the status of the test.

For the complete code of how to implement Travis test, refer to this Pull request in the Phimpme Android repository. In this Pull request, I did not make use of the sleep 300, due to which sometimes the test was failing without any broken UI. Hence, make sure to add this line of script for better results.

Resources:

https://docs.travis-ci.com/user/languages/android/

https://github.com/fossasia/phimpme-android