# 目次

1. 1-1. Introduction

2. 1-2. What are Manifest Merges?

3. 1-3. Common Reasons for Manifest Merge Failures

    - 1-3-1. Conflicting Permissions and Activities

    - 1-3-2. Incompatible Versions of Libraries

    - 1-3-3. Duplicate Attributes in Different Gradle Dependencies

4. 1-4. Diagnosing Manifest Merge Failures

   - 1-4-1. Using Android Studio's Built-in Tools

   - 1-4-2. Command-Line Tools for Deeper Analysis

5. 1-5. Steps to Resolve Manifest Merge Issues

   - 1-5-1. Analyze the Merge Result

   - 1-5-2. Use Explicit Merge Rules

   - 1-5-3. Address Version Conflicts

   - 1-5-4. Clean and Rebuild the Project

6. 1-6. Practical Example: Solving a Manifest Merge Failure

7. 1-7. Preventive Measures to Avoid Future Issues

8. 1-8. Summary

## 1-1. Introduction

When building Android applications, developers often encounter a variety of challenges, one of which is the dreaded "Manifest Merge failed" error. This can be particularly frustrating as it prevents the app from building altogether and can stem from seemingly innocuous changes in dependencies or project settings. In this article, we will delve deeply into what causes Manifest Merge failures and how to resolve them efficiently.

## 1-2. What are Manifest Merges?

Android applications rely on a manifest file `AndroidManifest.xml`, which serves as a crucial component of the app configuration, specifying essential elements like application permissions, activities, and services. During the build process, multiple manifest files from different libraries or modules can be merged into the single final manifest file for the app. This merging process is known as a "manifest merge."

## 1-3. Common Reasons for Manifest Merge Failures

### 1-3-1. Conflicting Permissions and Activities

One common reason for manifest merge failures is the presence of conflicting permissions, activities, or services in the manifest files. For example, if two libraries declare the same activity with different attributes, it may lead to a merge conflict.

### 1-3-2. Incompatible Versions of Libraries

Using libraries with incompatible or conflicting dependencies can also result in manifest merge issues. For instance, if one library requires a certain version of a Google Play service that another library is incompatible with, it can cause a merge failure.

### 1-3-3. Duplicate Attributes in Different Gradle Dependencies

Sometimes, duplicate attributes or incompatible configuration settings across different Gradle dependencies can also lead to manifest merging problems. This often occurs when different modules or libraries specify attributes like application IDs or resource names.

## 1-4. Diagnosing Manifest Merge Failures

### 1-4-1. Using Android Studio's Built-in Tools

One of the first steps in diagnosing manifest merge failures is to utilize Android Studio's built-in merge tool. When a merge conflict occurs, Android Studio usually provides error messages that indicate the nature of the conflict. Here's how you can access detailed merge information:

1. Navigate to the "Build" tab in Android Studio.

2. Click on the "Merge Manifests" option to view detailed information about the merge process.

3. Analyze the highlighted conflicts in the merged manifest view.

### 1-4-2. Command-Line Tools for Deeper Analysis

For developers comfortable with command-line tools, the `aapt` command can be used to inspect and manipulate the merged manifest file, providing deeper insights into the sources of conflict. A common usage is:

![img](/mosaic-code.jpg)

This command outputs a tree representation of the manifest file, helping developers pinpoint conflicts that might not be apparent in Android Studio.

## 1-5. Steps to Resolve Manifest Merge Issues

### 1-5-1. Analyze the Merge Result

Begin by thoroughly analyzing the merge result in Android Studio. Identify any conflicting elements, such as permissions, activities, or application settings, and understand their origins.

### 1-5-2. Use Explicit Merge Rules

Android Studio allows developers to write explicit merge rules in the manifest file to resolve conflicts. For example, if two libraries declare the same permission with conflicting attributes, you can specify which one should take precedence:

![img](/mosaic-code.jpg)

### 1-5-3. Address Version Conflicts

Ensure that all dependencies are compatible by aligning their versions. Use Gradle's dependency insight reports to examine all the versions being imported:

![img](/mosaic-code.jpg)

Ensure that there are no version conflicts in libraries that are merging manifest files.

### 1-5-4. Clean and Rebuild the Project

After making the necessary changes, clean and rebuild the project to ensure all changes are applied:

![img](/mosaic-code.jpg)

## 1-6. Practical Example: Solving a Manifest Merge Failure

Consider a scenario where the app's build process shows a failure due to conflicting permissions from two libraries (`Library A` and `Library B`). In this case:

1. Inspect the merge conflicts using Android Studio's manifest merge tool.

2. Identify that both libraries declare `android.permission.INTERNET`.

3. Use the merge rule to give precedence to one library, resolving the conflict.

4. Clean and rebuild the project to apply the changes.

## 1-7. Preventive Measures to Avoid Future Issues

To minimize the risk of future manifest merge errors, consider the following practices:

- Regularly update all dependencies to compatible versions.

- Regularly analyze dependencies using Gradle's dependency reporting tools.

- Document and maintain explicit merge rules for known conflicts in the `AndroidManifest.xml`.

## 1-8. Summary

Manifest merge failures can be a significant challenge for Android developers, but they are not insurmountable. Understanding the common causes of these errors, utilizing the right tools for diagnostics, and applying methodical solutions can help manage and resolve these issues more effectively. By adopting preventive measures and maintaining awareness of dependency management, developers can reduce the frequency and impact of these conflicts, resulting in smoother, more reliable builds.

# 目次

1. 1-1. Introduction

2. 1-2. What are Manifest Merges?

3. 1-3. Common Reasons for Manifest Merge Failures

    - 1-3-1. Conflicting Permissions and Activities

    - 1-3-2. Incompatible Versions of Libraries

    - 1-3-3. Duplicate Attributes in Different Gradle Dependencies

4. 1-4. Diagnosing Manifest Merge Failures

   - 1-4-1. Using Android Studio's Built-in Tools

   - 1-4-2. Command-Line Tools for Deeper Analysis

5. 1-5. Steps to Resolve Manifest Merge Issues

   - 1-5-1. Analyze the Merge Result

   - 1-5-2. Use Explicit Merge Rules

   - 1-5-3. Address Version Conflicts

   - 1-5-4. Clean and Rebuild the Project

6. 1-6. Practical Example: Solving a Manifest Merge Failure

7. 1-7. Preventive Measures to Avoid Future Issues

8. 1-8. Summary

## 1-1. Introduction

When building Android applications, developers often encounter a variety of challenges, one of which is the dreaded "Manifest Merge failed" error. This can be particularly frustrating as it prevents the app from building altogether and can stem from seemingly innocuous changes in dependencies or project settings. In this article, we will delve deeply into what causes Manifest Merge failures and how to resolve them efficiently.

## 1-2. What are Manifest Merges?

Android applications rely on a manifest file `AndroidManifest.xml`, which serves as a crucial component of the app configuration, specifying essential elements like application permissions, activities, and services. During the build process, multiple manifest files from different libraries or modules can be merged into the single final manifest file for the app. This merging process is known as a "manifest merge."

## 1-3. Common Reasons for Manifest Merge Failures

### 1-3-1. Conflicting Permissions and Activities

One common reason for manifest merge failures is the presence of conflicting permissions, activities, or services in the manifest files. For example, if two libraries declare the same activity with different attributes, it may lead to a merge conflict.

### 1-3-2. Incompatible Versions of Libraries

Using libraries with incompatible or conflicting dependencies can also result in manifest merge issues. For instance, if one library requires a certain version of a Google Play service that another library is incompatible with, it can cause a merge failure.

### 1-3-3. Duplicate Attributes in Different Gradle Dependencies

Sometimes, duplicate attributes or incompatible configuration settings across different Gradle dependencies can also lead to manifest merging problems. This often occurs when different modules or libraries specify attributes like application IDs or resource names.

## 1-4. Diagnosing Manifest Merge Failures

### 1-4-1. Using Android Studio's Built-in Tools

One of the first steps in diagnosing manifest merge failures is to utilize Android Studio's built-in merge tool. When a merge conflict occurs, Android Studio usually provides error messages that indicate the nature of the conflict. Here's how you can access detailed merge information:

1. Navigate to the "Build" tab in Android Studio.

2. Click on the "Merge Manifests" option to view detailed information about the merge process.

3. Analyze the highlighted conflicts in the merged manifest view.

### 1-4-2. Command-Line Tools for Deeper Analysis

For developers comfortable with command-line tools, the `aapt` command can be used to inspect and manipulate the merged manifest file, providing deeper insights into the sources of conflict. A common usage is:

```shell

aapt dump xmltree [APK_PATH] AndroidManifest.xml

```

This command outputs a tree representation of the manifest file, helping developers pinpoint conflicts that might not be apparent in Android Studio.

## 1-5. Steps to Resolve Manifest Merge Issues

### 1-5-1. Analyze the Merge Result

Begin by thoroughly analyzing the merge result in Android Studio. Identify any conflicting elements, such as permissions, activities, or application settings, and understand their origins.

### 1-5-2. Use Explicit Merge Rules

Android Studio allows developers to write explicit merge rules in the manifest file to resolve conflicts. For example, if two libraries declare the same permission with conflicting attributes, you can specify which one should take precedence:

```xml

<merge>

    <uses-permission android:name="android.permission.INTERNET" tools:node="replace" />

</merge>

```

### 1-5-3. Address Version Conflicts

Ensure that all dependencies are compatible by aligning their versions. Use Gradle's dependency insight reports to examine all the versions being imported:

```shell

./gradlew app:dependencies --configuration implementation

```

Ensure that there are no version conflicts in libraries that are merging manifest files.

### 1-5-4. Clean and Rebuild the Project

After making the necessary changes, clean and rebuild the project to ensure all changes are applied:

```shell

./gradlew clean

./gradlew build

```

## 1-6. Practical Example: Solving a Manifest Merge Failure

Consider a scenario where the app's build process shows a failure due to conflicting permissions from two libraries (`Library A` and `Library B`). In this case:

1. Inspect the merge conflicts using Android Studio's manifest merge tool.

2. Identify that both libraries declare `android.permission.INTERNET`.

3. Use the merge rule to give precedence to one library, resolving the conflict.

4. Clean and rebuild the project to apply the changes.

## 1-7. Preventive Measures to Avoid Future Issues

To minimize the risk of future manifest merge errors, consider the following practices:

- Regularly update all dependencies to compatible versions.

- Regularly analyze dependencies using Gradle's dependency reporting tools.

- Document and maintain explicit merge rules for known conflicts in the `AndroidManifest.xml`.

## 1-8. Summary

Manifest merge failures can be a significant challenge for Android developers, but they are not insurmountable. Understanding the common causes of these errors, utilizing the right tools for diagnostics, and applying methodical solutions can help manage and resolve these issues more effectively. By adopting preventive measures and maintaining awareness of dependency management, developers can reduce the frequency and impact of these conflicts, resulting in smoother, more reliable builds.

目次

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