Android Release Build Fails with Multiple Gradle Compatibility Issues

**Problem**

THIS REPORT WAS MOSTLY WRITTEN BY THE AI I WAS TROUBLESHOOTING WITH

Beyond that, the docs on android are way out of date and there is nearly no relevant info on anything to do with production build and config params.

Oh, and icon attachment doesn't work. Generally, any assets declared outside a .rs file are never read. And I only started problem-solving this when I FINALLY got the builder to read the Dioxus.toml file somewhat.

## Summary

`dx build --android --release` generates Gradle build files with **obsolete Java 8 configuration** that is incompatible with modern Android tooling (AGP 8.8+, Gradle 9.1+). Additionally, the build process fails due to:

1. **Java version mismatch** - Generated Gradle files use deprecated Java 8 (`VERSION_1_8`, `jvmTarget = "1.8"`)
2. **Lint validator crash** - `lintVitalAnalyzeRelease` task crashes with cryptic error "25.0.2"
3. **Deprecated manifest attributes** - Generated `AndroidManifest.xml` includes obsolete `android:extractNativeLibs="false"`

These issues **block Android release builds entirely** and require manual post-generation patching to succeed.

**Steps To Reproduce**

Steps to reproduce the behavior:

## Environment

- **Dioxus Version:** 0.7.3
- **Platform:** Android (Linux development environment, Arch-based)
- **Java Version:** OpenJDK 21.0.6
- **Gradle Version:** 9.1.0 (generated by dx)
- **Android Gradle Plugin:** 8.8.0
- **Target SDK:** 36 (Android 16 preview)
- **Min SDK:** 21

### Steps to Reproduce

1. Create a Dioxus mobile project with Android release configuration:

```toml
# Dioxus.toml
[application]
name = "amp"
version = "1.0.0"
default_platform = "mobile"
asset_dir = "assets"

[bundle.android]
min_sdk_version = 21
target_sdk_version = 36
orientation = "portrait"
jks_password = "${PASSWORD}"
key_password = "${PASSWORD}"
key_alias = "upload-key"
jks_file = "release.jks"

[bundle.android.permissions]
android.permission.LOCATION_FINE = true
android.permission.NOTIFICATIONS = true

[profile.android-release]
inherits = "release"
opt-level = 3
strip = false
```

2. Run Android release build:

```bash
dx build --android --release --device
```

**Expected behavior**

Build completes successfully and generates a signed APK compatible with modern Android tooling.

### Actual Behavior

Build fails with **three cascading errors**:

#### Error 1: Obsolete Java 8 Target

```
warning: [options] source value 8 is obsolete and will be removed in a future release
warning: [options] target value 8 is obsolete and will be removed in a future release
```

**Root Cause:** Generated `build.gradle.kts` contains:

```kotlin
compileOptions {
sourceCompatibility = JavaVersion.VERSION_1_8
targetCompatibility = JavaVersion.VERSION_1_8
}

kotlinOptions {
jvmTarget = "1.8"
}
```

#### Error 2: Lint Validator Crash

```
FAILURE: Build completed with 2 failures.

1: Task failed with an exception.
-----------
* What went wrong:
Execution failed for task ':app:lintVitalAnalyzeRelease'.
> A failure occurred while executing com.android.build.gradle.internal.lint.AndroidLintWorkAction
> 25.0.2
```

**Root Cause:** AGP 8.8 lint validator is incompatible with the generated Gradle configuration. The error message "25.0.2" provides no actionable information.

#### Error 3: Deprecated Manifest Attribute

```
> Task :app:packageRelease
PackagingOptions.jniLibs.useLegacyPackaging should be set to true because
android:extractNativeLibs is set to "true" in AndroidManifest.xml.
```

**Root Cause:** Generated `AndroidManifest.xml` includes deprecated `android:extractNativeLibs="false"` attribute.

## Workaround

A **post-generation patch script** is required to fix the generated Gradle files:

```bash
#!/bin/bash
set -e

ANDROID_DIR="target/dx/amp/release/android/app"

# Wait for dx to generate files
dx build --android --release --device || true

# Fix 1: Update Java version from 8 to 21
sed -i 's/VERSION_1_8/VERSION_21/g' "$ANDROID_DIR/build.gradle.kts"
sed -i 's/jvmTarget = "1.8"/jvmTarget = "21"/g' "$ANDROID_DIR/build.gradle.kts"

# Fix 2: Remove deprecated manifest attribute
sed -i 's/ android:extractNativeLibs="false"//g' \
"$ANDROID_DIR/src/main/AndroidManifest.xml"

# Fix 3: Skip broken lint tasks
"$ANDROID_DIR/gradlew" -p "$ANDROID_DIR" clean assembleRelease \
-x lintVitalAnalyzeRelease \
-x lintVitalRelease \
-x lintVitalReportRelease
```

**Full workaround script:** https://github.com/resonant-jovian/amp/blob/main/build.sh

## Proposed Solutions

### 1. Update Generated Gradle Files to Java 21

**File:** `dx` Android template generator

**Change:**

```kotlin
// Current (obsolete)
compileOptions {
sourceCompatibility = JavaVersion.VERSION_1_8
targetCompatibility = JavaVersion.VERSION_1_8
}
kotlinOptions {
jvmTarget = "1.8"
}

// Proposed
compileOptions {
sourceCompatibility = JavaVersion.VERSION_21
targetCompatibility = JavaVersion.VERSION_21
}
kotlinOptions {
jvmTarget = "21"
}
```

### 2. Fix Lint Configuration or Disable by Default

**Option A:** Add lint configuration to generated `build.gradle.kts`:

```kotlin
android {
lint {
checkReleaseBuilds = false
abortOnError = false
}
}
```

**Option B:** Skip lint tasks in `dx build` command by default:

```bash
./gradlew assembleRelease -x lintVitalAnalyzeRelease -x lintVitalRelease
```

### 3. Remove Deprecated Manifest Attributes

**File:** `dx` Android manifest template

**Change:** Remove or make conditional:

```xml

```

## Impact

This issue affects **all Android release builds** on systems with:
- Java 21 (current LTS and default on modern Linux distributions)
- Android Gradle Plugin 8.8+
- Gradle 9.1+

The workaround requires deep knowledge of Android build systems and is not discoverable through error messages.

## Additional Context

- The Java 8 deprecation was introduced in **JDK 20** (March 2023)
- Android Studio Ladybug+ defaults to **Java 21**
- Current Dioxus templates appear unmaintained since Java 8 era

**Environment:**

```
OS: Arch Linux (kernel 6.13.0)
Java: OpenJDK 21.0.6 2025-01-21
Rust: 1.84.0 (2025-01-09)
Dioxus CLI: 0.7.3
Android SDK: 36 (preview)
```

**Questionnaire**

I'm interested in fixing this myself but don't know where to start.
......I'm a rust dev man, I hate everything to do with or even slightly related to java with a burning passion but ui has to exist... apparently... idk cli is fine for me or whatever just give me a man file any day (this is a cry for help `$ man dx` `No manual entry for dx`)

---

**Related Issues:**
- Potentially related to Android Gradle Plugin version compatibility
- May be tied to Dioxus Android template generation in `dx` CLI

**Workaround Repository:** https://github.com/resonant-jovian/amp (see `build.sh`)