Android id naming convention: lower case with underscore vs. camel case

Question

I'm currently programming an application for the Android. Now what I found out is that you cannot place resource objects, say, an image in the drawable folder and name it like "myTestImage.jpg". This will give you a compiler error since camel case syntax is not allowed, so you'd have to rename it like "my_test_image.jpg". But what about ids you define in the XML file. Say you have the following definition ``` <TextView android:id="@+id/myTextViewFirstname" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Firstname" /> ``` This is a valid definition, compiles and works just fine on my Android emulator although - as you see - I'm specifying the id in camel case syntax. Now, the Android samples always use lower case and underscore. Is this just a naming convention to use lower case with underscore for the id's or may it cause problems on the real device? Thx

Accepted Answer

The device will not complain if you use camel-case id names. For my first application I wrote all the ids in camel-case because I think it appears better in the Java code that way, and it works just fine.

I am slowly changing my mind on camel-case, though, because you end up with two different naming conventions - for example:

```
// This must be undescored due to naming constrictions
setContentView(R.layout.my_long_layout_name);

// Now this looks a little out of place
findViewById(R.id.myLongSpecificId);
```

I, too, wonder about the standards here. Google is inconsistent in their examples; sometimes they use all lowercase, sometimes they insert underscores, and sometimes they use camel-case.

Android id naming convention: lower case with underscore vs. camel case

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