Android Studio: a picture is not displaying in the device but it does in the design

Question

I've added a sample picture into my app but it doesn't show on the device. What's wrong ?

Sample data (`tools:srcCompat="@tools:sample/...`) is for development tools, such as Android Studio. — CommonsWare, May 21 '22 at 20:21
@CommonsWare Sorry I didn't quite catch you. What is the right code to show up correctly on my device ? — user2925716, May 21 '22 at 20:28
Use `app:srcCompat` and point to an actual image, such as a drawable resource. Or, use an image-loading library (e.g., Glide, Picasso) and load an image at runtime (e.g., from a URL). — CommonsWare, May 21 '22 at 20:38
@CommonsWare When typing `app:` the whispering doesn't offer anything. BTW, what is the difference between `app:` and `android:` headers ? — user2925716, May 21 '22 at 20:49
@CommonsWare Can I make the picture trasparent so that if it is over a `editarea` the letters are visible ? — user2925716, May 21 '22 at 21:04
@user2925716 you can make any UI transparent as long as it has an alpha attribute. You can use `imageView.setAlpha(0)` in java or ` — ganjaam, May 22 '22 at 07:58
@user2925716 `app:` and `android:` are called namespaces. `android:` namespace is used for attributes of android SDK itself. refer to this link to learn more: https://stackoverflow.com/q/29732512/8192914 — ganjaam, May 22 '22 at 08:07

score 2 · Accepted Answer · answered May 22 '22 at 07:55

To display image, you should use app:srcCompat like the following.

<ImageView
            ...
            ...
            ...
            app:srcCompat="@drawable/resource_name" />

tools:srcCompat is responsible for showing the files in the IDE. It will not show the image in app.

Another approach to load image would be using Glide or Picasso library. You can find how to use them in their respective readme file.

1 Answers1