research and add an APK or AndroidManifest.xml validator

[silbinarywolf]

Edited (2024-10-01)

aapt2 add error checking for AndroidManifest.xml so the following PR changes this build SDK to use that.
#10

See:

• https://developer.android.com/tools/aapt2#aapt2_element_hierarchy
• Backup: http://web.archive.org/web/20241001070128/https://developer.android.com/tools/aapt2#aapt2_element_hierarchy

Original Post

If you slightly mess up the XML in your AndroidManifest.xml file, you should ideally get an obvious compilation error.
For example, OpenXR wasn't working for me because I had failed to put a category within the intent filter.

Todo

Look into the apkanalyzer command line tool and invoke it testing the broken and then fixed version.
See: https://developer.android.com/studio/debug/apk-analyzer

Alternatively we could look at using the lint command here: https://developer.android.com/studio/write/lint.

Both of these commands exist in Android\Sdk\tools\bin

Broken/invalid XML

<activity android:name="HelloVRSDLActivity"
            android:label="@string/app_name"
            android:alwaysRetainTaskState="true"
            android:launchMode="singleInstance"
            android:configChanges="layoutDirection|locale|orientation|uiMode|screenLayout|screenSize|smallestScreenSize|keyboard|keyboardHidden|navigation"
            android:preferMinimalPostProcessing="true"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
                <category android:name="org.khronos.openxr.intent.category.IMMERSIVE_HMD" />
            </intent-filter>

Correct valid XML

<activity android:name="HelloVRSDLActivity"
            android:label="@string/app_name"
            android:alwaysRetainTaskState="true"
            android:launchMode="singleInstance"
            android:configChanges="layoutDirection|locale|orientation|uiMode|screenLayout|screenSize|smallestScreenSize|keyboard|keyboardHidden|navigation"
            android:preferMinimalPostProcessing="true"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
            <category android:name="org.khronos.openxr.intent.category.IMMERSIVE_HMD" />

[silbinarywolf]

I looked into lint yesterday and while it does tell you about unused fields and whatnot, it won't inform you of errors.

However it looks like aapt2 is capable of doing this kind of error checking:
https://developer.android.com/tools/aapt2#aapt2_element_hierarchy