开发笔记:Gradle之AndroidGradlePlugin主要Task分析

List splitsToGenerate =
getApksToGenerate(outputScope, supportedAbis, buildTargetAbi, buildTargetDensity);

android {
splits {
// Configures multiple APKs based on screen density.
density {
// Configures multiple APKs based on screen density.
enable true
// Specifies a list of screen densities Gradle should not create multiple APKs for.
exclude "ldpi", "xxhdpi", "xxxhdpi"
// Specifies a list of compatible screen size settings for the manifest.
compatibleScreens \'small\', \'normal\', \'large\', \'xlarge\'
}
}
}

// ProcessAndroidResources.doFullTaskAction
List apkDataList = new ArrayList<>(splitsToGenerate);
for (ApkData apkData : splitsToGenerate) {
if (apkData.requiresAapt()) {
// 这里只处理 main 和不依赖 density 的资源
boolean codeGen =
(apkData.getType() == OutputFile.OutputType.MAIN
|| apkData.getFilter(OutputFile.FilterType.DENSITY) == null);
if (codeGen) {
apkDataList.remove(apkData);
invokeAaptForSplit(
manifestsOutputs,
libraryInfoList,
packageIdFileSet,
splitList,
featureResourcePackages,
apkData,
codeGen,
aapt);
break;
}
}
}

// ProcessAndroidResources.invokeAaptForSplit
void invokeAaptForSplit(...) {
// ...
String packageForR = null;
File srcOut = null;
File symbolOutputDir = null;
File proguardOutputFile = null;
File mainDexListProguardOutputFile = null;
// 如果传了 generateCode 参数，会生成 R.java
if (generateCode) {
packageForR = originalApplicationId;
// we have to clean the source folder output in case the package name changed.
srcOut = getSourceOutputDir();
if (srcOut != null) {
FileUtils.cleanOutputDir(srcOut);
}
symbolOutputDir = textSymbolOutputDir.get();
proguardOutputFile = getProguardOutputFile();
mainDexListProguardOutputFile = getMainDexListProguardOutputFile();
}
// ...
getBuilder().processResources(aapt, config);
}

performSystemPropertiesInjection(mergingReportBuilder, xmlDocumentOptional.get());
// ManifestMerger2.performSystemPropertiesInjection
protected void performSystemPropertiesInjection(
@NonNull MergingReport.Builder mergingReport,
@NonNull XmlDocument xmlDocument) {
for (ManifestSystemProperty manifestSystemProperty : ManifestSystemProperty.values()) {
String propertyOverride = mSystemPropertyResolver.getValue(manifestSystemProperty);
if (propertyOverride != null) {
manifestSystemProperty.addTo(
mergingReport.getActionRecorder(), xmlDocument, propertyOverride);
}
}
}

for (File inputFile : mFlavorsAndBuildTypeFiles) {
LoadedManifestInfo overlayDocument = load(
new ManifestInfo(null, inputFile, XmlDocument.Type.OVERLAY,
Optional.of(mainPackageAttribute.get().getValue())),
selectors,
mergingReportBuilder);
// 检查 package 定义
Optional packageAttribute =
overlayDocument.getXmlDocument().getPackage();
if (loadedMainManifestInfo.getOriginalPackageName().isPresent() &&
packageAttribute.isPresent()
&& !loadedMainManifestInfo.getOriginalPackageName().get().equals(
packageAttribute.get().getValue())) {
// 如果 package 定义重复的话，会输出下面信息，我们平时应该或多或少见过类似的错误
String message = mMergeType == MergeType.APPLICATION
? String.format(
"Overlay manifest:package attribute declared at %1$s value=(%2$s)\\n"
+ "\\thas a different value=(%3$s) "
+ "declared in main manifest at %4$s\\n"
+ "\\tSuggestion: remove the overlay declaration at %5$s "
+ "\\tand place it in the build.gradle:\\n"
+ "\\t\\tflavorName {\\n"
+ "\\t\\t\\tapplicatiOnId= \\"%2$s\\"\\n"
+ "\\t\\t}",
packageAttribute.get().printPosition(),
packageAttribute.get().getValue(),
mainPackageAttribute.get().getValue(),
mainPackageAttribute.get().printPosition(),
packageAttribute.get().getSourceFile().print(true))
: String.format(
"Overlay manifest:package attribute declared at %1$s value=(%2$s)\\n"
+ "\\thas a different value=(%3$s) "
+ "declared in main manifest at %4$s",
packageAttribute.get().printPosition(),
packageAttribute.get().getValue(),
mainPackageAttribute.get().getValue(),
mainPackageAttribute.get().printPosition());
// ...
return mergingReportBuilder.build();
}
}

DexArchiveBuilderTransform.transform -> DexArchiveBuilderTransform.convertJarToDexArchive -> DexArchiveBuilderTransform.convertToDexArchive -> DexArchiveBuilderTransform.launchProcessing -> DxDexArchiveBuilder.convert