Image from Android expansion file appears too small

Issue

I am in the process of implementing expansion files for my Android app.

So far, I've placed several images and audio files into the main expansion file (I am not using the patch expansion file). None of the files have been compressed.

Through the app, I am able to download the expansion file, and play the audio files without any problems. At the same time an audio file in the expansion file is played, I am also displaying an image from the expansion file. However, the image is considerably smaller than I expected.

The image is 320x400px. Before implementing the expansion files, it was displayed as expected in my app. However, after implementation, it looks like the image shrank to about 50px wide (the height shrank in proportion).

I then tried the solution offered in How to create a drawable from a stream without resizing it. While the image does appear slightly larger, it is still much smaller than what I want it to be (looks like it's about 100x125 px now). Currently, my code for displaying the image looks like this:

public void displayImageFromExpansionFile(){
    Bitmap b = BitmapFactory.decodeStream(fileStream);
    b.setDensity(Bitmap.DENSITY_NONE);
    Drawable d = new BitmapDrawable(this.getResources(), b);
    imageToDisplay.setImageDrawable(d);
}

public void showImg(int imgNum){
    switch(imgNum){
        case(1):
            try{
                if((getResources().getConfiguration().screenLayout & 
                        Configuration.SCREENLAYOUT_SIZE_MASK) == Configuration.SCREENLAYOUT_SIZE_SMALL){
                    fileStream = expansionFile.getInputStream("filepath inside expansion file for small image");
                }
                else if((getResources().getConfiguration().screenLayout & 
                        Configuration.SCREENLAYOUT_SIZE_MASK) == Configuration.SCREENLAYOUT_SIZE_NORMAL){                       
                    fileStream = expansionFile.getInputStream("filepath inside expansion file for normal image");
                }
                else if((getResources().getConfiguration().screenLayout & 
                        Configuration.SCREENLAYOUT_SIZE_MASK) == Configuration.SCREENLAYOUT_SIZE_LARGE){
                    fileStream = expansionFile.getInputStream("filepath inside expansion file for large image");
                }
                else{
                    fileStream = expansionFile.getInputStream("filepath inside expansion file for xlarge image");
                }
                displayImageFromExpansionFile();
            } catch (Exception e) {
                e.printStackTrace();
            }           
            break;
        // more cases here
}

It still seems as if the image is not being displayed at its actual size. When I examine the image inside the expansion file, I can see that it is still at 320x400px. However, the app is not displaying the image at these dimensions.

What could I do to get the app to display the image at its correct dimensions?

Thanks!

---UPDATE---

I've also tried the code below, with no difference in results. It still looks to be about 100x125px, instead of 320x400px, like its original size.

public void displayImageFromExpansionFile(int bWidth, int bHeight){
    BitmapFactory.Options bfo = new BitmapFactory.Options();
    bfo.inPreferredConfig = Bitmap.Config.ARGB_8888;
    Bitmap b = BitmapFactory.decodeStream(fileStream, null, bfo);
    b.setDensity(Bitmap.DENSITY_NONE);
    imageToDisplay.setImageBitmap(b);
}

The only thing that's worked so far is Bitmap.createScaledBitmap(b, bWidth, bHeight, true);

On my phone, doubling the image's original dimensions (to 640x800 px) using the above method brings the image up to its expected size, but I would imagine that the image might appear at different sizes on different phones (probably because of screen density/size). When I tried doubling the xlarge image dimensions and viewed it on my tablet, the image appears larger than it should.

Solution

In the end, I fiddled around with the layout XML file that was displaying the shrunken image. I changed the attributes of the imageView like so:

• Width / Height: fill_parent (both)

• Scale Type: fitCenter

Now, the images are slightly bigger than I initially expected, but I think it looks better this way. And now the images are of a consistent size. Problem solved!

If anyone else is having trouble with what I've been experiencing, hope this helps.

Answered By - Null_In_The_Skull