Android AAPT(Android Asset Packaging Tool)详解

aapt l /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/build/outputs/apk/app-debug.apk

aapt l -v /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/build/outputs/apk/app-debug.apk

aapt l -a /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/build/outputs/apk/app-debug.apk 

aapt dump strings /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/build/outputs/apk/app-debug.apk

aapt dump badging /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/build/outputs/apk/app-debug.apk

aapt dump resources /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/build/outputs/apk/app-debug.apk

aapt dump configurations /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/build/outputs/apk/app-debug.apk

aapt d xmltree /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/build/outputs/apk/app-debug.apk res/layout/activity_main.xml

aapt d xmlstrings /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/build/outputs/apk/app-debug.apk res/layout/activity_main.xml

aapt p[ackage] [-d][-f][-m][-u][-v][-x][-z][-M AndroidManifest.xml] \
        [-0 extension [-0 extension ...]] [-g tolerance] [-j jarfile] \
        [--debug-mode] [--min-sdk-version VAL] [--target-sdk-version VAL] \
        [--app-version VAL] [--app-version-name TEXT] [--custom-package VAL] \
        [--rename-manifest-package PACKAGE] \
        [--rename-instrumentation-target-package PACKAGE] \
        [--utf16] [--auto-add-overlay] \
        [--max-res-version VAL] \
        [-I base-package [-I base-package ...]] \
        [-A asset-source-dir]  [-G class-list-file] [-P public-definitions-file] \
        [-D main-dex-class-list-file] \
        [-S resource-sources [-S resource-sources ...]] \
        [-F apk-file] [-J R-file-dir] \
        [--product product1,product2,...] \
        [-c CONFIGS] [--preferred-density DENSITY] \
        [--split CONFIGS [--split CONFIGS]] \
        [--feature-of package [--feature-after package]] \
        [raw-files-dir [raw-files-dir] ...] \
        [--output-text-symbols DIR]

aapt package -f -S /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/src/main/res -I /Users/zfxu/Library/Android/sdk/platforms/android-25/android.jar -A /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/src/main/assets -M /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/src/main/AndroidManifest.xml -F /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/out.apk

aapt package -m -J <R.java目录> -S <res目录> -I <android.jar目录> -M <AndroidManifest.xml目录>

aapt package –m –J <R.java目录> -S <res目录> -I <android.jar目录> -M <AndroidManifest.xml目录>

aapt package -m -J /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/ -S /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/src/main/res/ -I /Users/zfxu/Library/Android/sdk/platforms/android-25/android.jar -M /Users/zfxu/work/androidstudio_workspace/AAPTDemo/app/src/main/AndroidManifest.xml

public final class R {
    public static final class attr {
    }
    public static final class color {
        public static final int colorAccent=0x7f040002;
        public static final int colorPrimary=0x7f040000;
        public static final int colorPrimaryDark=0x7f040001;
    }
    public static final class layout {
        public static final int activity_main=0x7f030000;
    }
    public static final class mipmap {
        public static final int ic_launcher=0x7f020000;
        public static final int ic_launcher_round=0x7f020001;
    }
    public static final class string {
        public static final int app_name=0x7f050000;
    }
}

int main(int argc, char* const argv[]) {
    ***
    else if (argv[1][0] == 'p')
        bundle.setCommand(kCommandPackage);
    ***
    while (argc && argv[0][0] == '-') {
        //通过case比较，去除命令中所有的参数，并且放进bundle中
        /* flag(s) found */
        const char* cp = argv[0] +1;
        while (*cp != '\0') {
            ***
            switch (*cp) {
            case 'M':
                argc--;
                argv++;
                if (!argc) {
                    fprintf(stderr, "ERROR: No argument supplied for '-M' option\n");
                    wantUsage = true;
                    goto bail;
                }
                //这个仅仅是把传进来的地址坐下系统路径分割线的转换
                convertPath(argv[0]);
                bundle.setAndroidManifestFile(argv[0]);
                break;
            }
            ***
        }
    }
    ***
    result = handleCommand(&bundle);
    ***
}

 int handleCommand(Bundle* bundle){
    switch (bundle->getCommand()) {
        case kCommandVersion:      return doVersion(bundle);
        case kCommandList:         return doList(bundle);
        case kCommandDump:         return doDump(bundle);
        case kCommandAdd:          return doAdd(bundle);
        case kCommandRemove:       return doRemove(bundle);
        case kCommandPackage:      return doPackage(bundle);
        case kCommandCrunch:       return doCrunch(bundle);
        case kCommandSingleCrunch: return doSingleCrunch(bundle);
        case kCommandDaemon:       return runInDaemonMode(bundle);
        default:
            fprintf(stderr, "%s: requested command not yet supported\n", gProgName);
            return 1;
    }
}

int doPackage(Bundle* bundle) {
    const char* outputAPKFile;
    int retVal = 1;
    status_t err;
    sp<AaptAssets> assets;
    int N;
    FILE* fp;
    String8 dependencyFile;
    sp<ApkBuilder> builder;

    sp<WeakResourceFilter> configFilter = new WeakResourceFilter();
    //见注释3-1
    err = configFilter->parse(bundle->getConfigurations());
    if (err != NO_ERROR) {
        goto bail;
    }

    //资源本地化相关的配置，具体什么含义也没有理解清楚
    if (configFilter->containsPseudo()) {
        bundle->setPseudolocalize(bundle->getPseudolocalize() | PSEUDO_ACCENTED);
    }
    if (configFilter->containsPseudoBidi()) {
        bundle->setPseudolocalize(bundle->getPseudolocalize() | PSEUDO_BIDI);
    }

    //校验命令中是否传入正确的参数
    N = bundle->getFileSpecCount();
    if (N < 1 && bundle->getResourceSourceDirs().size() == 0 && bundle->getJarFiles().size() == 0
            && bundle->getAndroidManifestFile() == NULL && bundle->getAssetSourceDirs().size() == 0) {
        fprintf(stderr, "ERROR: no input files\n");
        goto bail;
    }

    outputAPKFile = bundle->getOutputAPKFile();

    // 如果输出文件存在，但是是不合格的，则直接报错结束，如果不存在，则新建空文件
    if (outputAPKFile) {
        FileType type;
        type = getFileType(outputAPKFile);
        if (type != kFileTypeNonexistent && type != kFileTypeRegular) {
            fprintf(stderr,
                "ERROR: output file '%s' exists but is not regular file\n",
                outputAPKFile);
            goto bail;
        }
    }

    // Load the assets.
    assets = new AaptAssets();
    
    // 设置res和asset的成员,仅仅是外层new一个对象赋值给AaptAssets
    if (bundle->getGenDependencies()) {
        sp<FilePathStore> resPathStore = new FilePathStore;
        assets->setFullResPaths(resPathStore);
        sp<FilePathStore> assetPathStore = new FilePathStore;
        assets->setFullAssetPaths(assetPathStore);
    }
    //调用AaptAssets类的成员函数slurpFromArgs将AndroidManifest.xml文件，目录assets和res下的资源目录和资源文件收录起来保存到AaptAssets中的
    //成员变量中
    err = assets->slurpFromArgs(bundle);
    if (err < 0) {
        goto bail;
    }
    //如果命令中指定需要详细日志输出，这里会打印所有的资源信息
    if (bundle->getVerbose()) {
        assets->print(String8());
    }

    // Create the ApkBuilder, which will collect the compiled files
    // to write to the final APK (or sets of APKs if we are building
    // a Split APK.
    //new一个ApkBuilder对象，如果需要生成多个apk，则需要将上层的配置写入改对象中
    builder = new ApkBuilder(configFilter);
    // If we are generating a Split APK, find out which configurations to split on.
    if (bundle->getSplitConfigurations().size() > 0) {
        const Vector<String8>& splitStrs = bundle->getSplitConfigurations();
        const size_t numSplits = splitStrs.size();
        for (size_t i = 0; i < numSplits; i++) {
            std::set<ConfigDescription> configs;
            if (!AaptConfig::parseCommaSeparatedList(splitStrs[i], &configs)) {
                fprintf(stderr, "ERROR: failed to parse split configuration '%s'\n", splitStrs[i].string());
                goto bail;
            }

            err = builder->createSplitForConfigs(configs);
            if (err != NO_ERROR) {
                goto bail;
            }
        }
    }

    // If they asked for any fileAs that need to be compiled, do so.
    //这是最核心的一步，编译资源(res和asset)。这个成功后，下面的步骤就仅仅是写输出文件了
    if (bundle->getResourceSourceDirs().size() || bundle->getAndroidManifestFile()) {
        err = buildResources(bundle, assets, builder);
        if (err != 0) {
            goto bail;
        }
    }

    // At this point we've read everything and processed everything.  From here
    // on out it's just writing output files.
    if (SourcePos::hasErrors()) {
        goto bail;
    }

    // Update symbols with information about which ones are needed as Java symbols.
    assets->applyJavaSymbols();
    if (SourcePos::hasErrors()) {
        goto bail;
    }

    // If we've been asked to generate a dependency file, do that here
    if (bundle->getGenDependencies()) {
        // If this is the packaging step, generate the dependency file next to
        // the output apk (e.g. bin/resources.ap_.d)
        if (outputAPKFile) {
            dependencyFile = String8(outputAPKFile);
            // Add the .d extension to the dependency file.
            dependencyFile.append(".d");
        } else {
            // Else if this is the R.java dependency generation step,
            // generate the dependency file in the R.java package subdirectory
            // e.g. gen/com/foo/app/R.java.d
            dependencyFile = String8(bundle->getRClassDir());
            dependencyFile.appendPath("R.java.d");
        }
        // Make sure we have a clean dependency file to start with
        fp = fopen(dependencyFile, "w");
        fclose(fp);
    }

    // Write out R.java constants
    if (!assets->havePrivateSymbols()) {
        if (bundle->getCustomPackage() == NULL) {
            // Write the R.java file into the appropriate class directory
            // e.g. gen/com/foo/app/R.java
            err = writeResourceSymbols(bundle, assets, assets->getPackage(), true,
                    bundle->getBuildSharedLibrary());
        } else {
            const String8 customPkg(bundle->getCustomPackage());
            err = writeResourceSymbols(bundle, assets, customPkg, true,
                    bundle->getBuildSharedLibrary());
        }
        if (err < 0) {
            goto bail;
        }
        // If we have library files, we're going to write our R.java file into
        // the appropriate class directory for those libraries as well.
        // e.g. gen/com/foo/app/lib/R.java
        if (bundle->getExtraPackages() != NULL) {
            // Split on colon
            String8 libs(bundle->getExtraPackages());
            char* packageString = strtok(libs.lockBuffer(libs.length()), ":");
            while (packageString != NULL) {
                // Write the R.java file out with the correct package name
                err = writeResourceSymbols(bundle, assets, String8(packageString), true,
                        bundle->getBuildSharedLibrary());
                if (err < 0) {
                    goto bail;
                }
                packageString = strtok(NULL, ":");
            }
            libs.unlockBuffer();
        }
    } else {
        err = writeResourceSymbols(bundle, assets, assets->getPackage(), false, false);
        if (err < 0) {
            goto bail;
        }
        err = writeResourceSymbols(bundle, assets, assets->getSymbolsPrivatePackage(), true, false);
        if (err < 0) {
            goto bail;
        }
    }

    // Write out the ProGuard file
    err = writeProguardFile(bundle, assets);
    if (err < 0) {
        goto bail;
    }

    // Write the apk
    if (outputAPKFile) {
        // Gather all resources and add them to the APK Builder. The builder will then
        // figure out which Split they belong in.
        err = addResourcesToBuilder(assets, builder);
        if (err != NO_ERROR) {
            goto bail;
        }

        const Vector<sp<ApkSplit> >& splits = builder->getSplits();
        const size_t numSplits = splits.size();
        for (size_t i = 0; i < numSplits; i++) {
            const sp<ApkSplit>& split = splits[i];
            String8 outputPath = buildApkName(String8(outputAPKFile), split);
            err = writeAPK(bundle, outputPath, split);
            if (err != NO_ERROR) {
                fprintf(stderr, "ERROR: packaging of '%s' failed\n", outputPath.string());
                goto bail;
            }
        }
    }

    // If we've been asked to generate a dependency file, we need to finish up here.
    // the writeResourceSymbols and writeAPK functions have already written the target
    // half of the dependency file, now we need to write the prerequisites. (files that
    // the R.java file or .ap_ file depend on)
    if (bundle->getGenDependencies()) {
        // Now that writeResourceSymbols or writeAPK has taken care of writing
        // the targets to our dependency file, we'll write the prereqs
        fp = fopen(dependencyFile, "a+");
        fprintf(fp, " : ");
        bool includeRaw = (outputAPKFile != NULL);
        err = writeDependencyPreReqs(bundle, assets, fp, includeRaw);
        // Also manually add the AndroidManifeset since it's not under res/ or assets/
        // and therefore was not added to our pathstores during slurping
        fprintf(fp, "%s \\\n", bundle->getAndroidManifestFile());
        fclose(fp);
    }

    retVal = 0;
bail:
    if (SourcePos::hasErrors()) {
        SourcePos::printErrors(stderr);
    }
    return retVal;
}

status_t buildResources(Bundle* bundle, const sp<AaptAssets>& assets, sp<ApkBuilder>& builder)
{
    // First, look for a package file to parse.  This is required to
    // be able to generate the resource information.
    sp<AaptGroup> androidManifestFile =
            assets->getFiles().valueFor(String8("AndroidManifest.xml"));
    if (androidManifestFile == NULL) {
        fprintf(stderr, "ERROR: No AndroidManifest.xml file found.\n");
        return UNKNOWN_ERROR;
    }

    status_t err = parsePackage(bundle, assets, androidManifestFile);
    if (err != NO_ERROR) {
        return err;
    }

    ......
}

static status_t parsePackage(Bundle* bundle, const sp<AaptAssets>& assets,
    const sp<AaptGroup>& grp)
{
    if (grp->getFiles().size() != 1) {
        fprintf(stderr, "warning: Multiple AndroidManifest.xml files found, using %s\n",
                grp->getFiles().valueAt(0)->getPrintableSource().string());
    }

    sp<AaptFile> file = grp->getFiles().valueAt(0);

    ResXMLTree block;
    status_t err = parseXMLResource(file, &block);
    if (err != NO_ERROR) {
        return err;
    }
    ......省略代码
    return NO_ERROR;
}

ResourceTable::PackageType packageType = ResourceTable::App;
    ......省略的代码
    if (bundle->getBuildSharedLibrary()) {
        packageType = ResourceTable::SharedLibrary;
    } else if (bundle->getExtending()) {
        packageType = ResourceTable::System;
    } else if (!bundle->getFeatureOfPackage().isEmpty()) {
        packageType = ResourceTable::AppFeature;
    }

    ResourceTable table(bundle, String16(assets->getPackage()), packageType);
    err = table.addIncludedResources(bundle, assets);
    if (err != NO_ERROR) {
        return err;
    }
    ...省略的代码

ResourceTable::ResourceTable(Bundle* bundle, const String16& assetsPackage, ResourceTable::PackageType type)
    : mAssetsPackage(assetsPackage)
    , mPackageType(type)
    , mTypeIdOffset(0)
    , mNumLocal(0)
    , mBundle(bundle) {
    ssize_t packageId = -1;
    switch (mPackageType) {
        case App:
        case AppFeature:
            packageId = 0x7f;
            break;

        case System:
            packageId = 0x01;
            break;

        case SharedLibrary:
            packageId = 0x00;
            break;

        default:
            assert(0);
            break;
    }
    sp<Package> package = new Package(mAssetsPackage, packageId);
    mPackages.add(assetsPackage, package);
    mOrderedPackages.add(package);

    // Every resource table always has one first entry, the bag attributes.
    const SourcePos unknown(String8("????"), 0);
    getType(mAssetsPackage, String16("attr"), unknown);
}

...省略代码
// Write out R.java constants
    if (!assets->havePrivateSymbols()) {
        if (bundle->getCustomPackage() == NULL) {
            // Write the R.java file into the appropriate class directory
            // e.g. gen/com/foo/app/R.java
            err = writeResourceSymbols(bundle, assets, assets->getPackage(), true,
                    bundle->getBuildSharedLibrary());
        } else {
            const String8 customPkg(bundle->getCustomPackage());
            err = writeResourceSymbols(bundle, assets, customPkg, true,
                    bundle->getBuildSharedLibrary());
        }
        if (err < 0) {
            goto bail;
        }
        // If we have library files, we're going to write our R.java file into
        // the appropriate class directory for those libraries as well.
        // e.g. gen/com/foo/app/lib/R.java
        if (bundle->getExtraPackages() != NULL) {
            // Split on colon
            String8 libs(bundle->getExtraPackages());
            char* packageString = strtok(libs.lockBuffer(libs.length()), ":");
            while (packageString != NULL) {
                // Write the R.java file out with the correct package name
                err = writeResourceSymbols(bundle, assets, String8(packageString), true,
                        bundle->getBuildSharedLibrary());
                if (err < 0) {
                    goto bail;
                }
                packageString = strtok(NULL, ":");
            }
            libs.unlockBuffer();
        }
    } else {
        err = writeResourceSymbols(bundle, assets, assets->getPackage(), false, false);
        if (err < 0) {
            goto bail;
        }
        err = writeResourceSymbols(bundle, assets, assets->getSymbolsPrivatePackage(), true, false);
        if (err < 0) {
            goto bail;
        }
    }
...省略代码