升级Gradle 4.4后AndroidManifest.xml大量报错求助（禁用Aapt2方案勿提）

Hey there, I’ve run into this exact headache when upgrading to Gradle 4.4 (which pairs with Android Gradle Plugin 3.1.x, where AAPT2 is enforced by default). AAPT2 is way stricter about Manifest syntax and validity than the old AAPT, so those errors aren’t just noise—they’re pointing to real issues in your file that were quietly ignored before. Let’s walk through the most common fixes to get things back on track:

1. Fix Invalid Attribute Values or Types #

AAPT2 enforces strict type checking for Android’s built-in attributes. For example:

• android:versionCode must be a plain integer (while XML technically allows quoting it, AAPT2 might flag edge cases where quoted values conflict with build.gradle overrides). Double-check you haven’t accidentally added non-numeric characters here, like android:versionCode="v123".
• android:versionName needs to be a properly quoted string—don’t skip the quotes or use invalid characters.
• For <uses-sdk> attributes like android:minSdkVersion, ensure the value is a valid integer, not a string with extra symbols.

Lean on the error messages—they’ll usually call out exactly which attribute is causing trouble. For the snippet you shared, start by verifying android:versionCode="1" is formatted correctly and not being overridden incorrectly in your build.gradle.

2. Remove Duplicate Declarations #

AAPT2 will flag duplicate permissions, activities, or metadata entries that the old AAPT let slide. Do a quick sweep of your Manifest:

• Are there multiple <uses-permission> tags for the same permission?
• Did you accidentally declare the same activity twice (once in your main Manifest and once in a library’s)?
• Do you have duplicate <meta-data> entries under the same component (like <application> or an <activity>)?

Use Android Studio’s "Find in Path" tool to hunt down duplicates fast.

3. Correct Custom Attribute Namespaces #

If you’re using custom attributes (from libraries or your own code), make sure you’ve declared the namespace correctly at the root of your Manifest or relevant tag. For example:

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          xmlns:tools="http://schemas.android.com/tools"
          xmlns:custom="http://schemas.android.com/apk/res-auto">

Forgot to declare a namespace for an attribute like custom:theme? AAPT2 will throw an error immediately—no more ignoring that mistake.

4. Fix Invalid Tag Order #

AAPT2 enforces the official Android Manifest tag order strictly. The required sequence is:

<manifest>
  <uses-permission>
  <permission>
  <permission-group>
  <permission-tree>
  <instrumentation>
  <application>

If you have tags out of order (like an <application> tag before <uses-permission>), AAPT2 will call you out. Use Android Studio’s "Reformat Code" shortcut (Ctrl+Alt+L / Cmd+Opt+L) to auto-fix this—it adheres to the schema perfectly.

5. Resolve Library Manifest Conflicts #

Third-party libraries often have Manifest entries that clash with yours (like duplicate permissions or conflicting android:icon declarations). Use the tools:replace attribute to resolve these explicitly. For example, if a library sets an icon that clashes with yours:

<application
    android:icon="@mipmap/ic_launcher"
    tools:replace="android:icon">

Just make sure you’ve declared the tools namespace at the root of your Manifest first.

6. Hunt for Typos in Attribute Names #

AAPT2 has zero patience for typos that the old AAPT ignored. Double-check every attribute name—like android:launchMode instead of android:launchmode, or android:configChanges instead of android:configchange. These tiny mistakes would fly under the radar before, but now they’ll throw hard errors.

Once you work through these steps, most of your Manifest errors should vanish. Remember, AAPT2’s strictness is a good thing—it helps catch issues that could cause runtime crashes or Play Store submission failures down the line.

内容的提问来源于stack exchange，提问作者Ciprian Ivan