Style Element with android:id Crashes AAPT

ID

java.android_aapt_crash

Severity

low

Remediation Complexity

trivial

Remediation Risk

low

Remediation Effort

low

Resource

Reliability

Language

Java

Tags

android, reliability

Description

Reports <style> elements in Android layout XML files that declare an android:id attribute. Assigning an android:id="@+id/…​" on a <style> element causes the Android Asset Packaging Tool (AAPT) to crash at build time with an obscure error, preventing the APK from being assembled.

Rationale

The <style> element is a resource container, not a UI widget. It has no visual representation in the view hierarchy and therefore cannot be referenced by ID at runtime. When AAPT encounters an android:id on a <style>, it enters an unsupported code path and crashes with an internal error.

<!-- Bad: style with android:id crashes AAPT -->
<style android:id="@+id/my_style"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">
</style>

This typically happens when a developer copies a widget element and changes its tag to <style> without removing the android:id attribute.

Remediation

Remove the android:id attribute from the <style> element. If you need a named style, define it in res/values/styles.xml with a name attribute instead.

<!-- Good: style without android:id -->
<style
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">
</style>

<!-- Or define the style properly in res/values/styles.xml -->
<!-- <style name="MyStyle"> ... </style> -->

References