Add --non-constant-id to aapt.

This option enbables creating resource constant in the R class
that are not actual constant, but simply static fields.

The goal is to build library projects with these types of
IDs so that the constant does not get inlined in the library
code, since the ID for the library resources only are not
the final values.

The final resource IDs, generated from the main project and
its library(ies), will have proper constant with the final
values.

This allows us to generate binary library bundle (a jar file
and associated resources) that can be distributed. Additionally,
this will let us make the library project support in Eclipse
much more robust and a better user experience overall.

Change-Id: Ibe2f08d68493fde658fc3f7606abf7446f312ad2
diff --git a/tools/aapt/Bundle.h b/tools/aapt/Bundle.h
index c5aa573..15570e4 100644
--- a/tools/aapt/Bundle.h
+++ b/tools/aapt/Bundle.h
@@ -45,7 +45,7 @@
           mRClassDir(NULL), mResourceIntermediatesDir(NULL), mManifestMinSdkVersion(NULL),
           mMinSdkVersion(NULL), mTargetSdkVersion(NULL), mMaxSdkVersion(NULL),
           mVersionCode(NULL), mVersionName(NULL), mCustomPackage(NULL),
-          mMaxResVersion(NULL), mDebugMode(false), mProduct(NULL),
+          mMaxResVersion(NULL), mDebugMode(false), mNonConstantId(false), mProduct(NULL),
           mArgc(0), mArgv(NULL)
         {}
     ~Bundle(void) {}
@@ -139,6 +139,8 @@
     void setMaxResVersion(const char * val) { mMaxResVersion = val; }
     bool getDebugMode() { return mDebugMode; }
     void setDebugMode(bool val) { mDebugMode = val; }
+    bool getNonConstantId() { return mNonConstantId; }
+    void setNonConstantId(bool val) { mNonConstantId = val; }
     const char* getProduct() const { return mProduct; }
     void setProduct(const char * val) { mProduct = val; }
 
@@ -239,6 +241,7 @@
     const char* mCustomPackage;
     const char* mMaxResVersion;
     bool        mDebugMode;
+    bool        mNonConstantId;
     const char* mProduct;
 
     /* file specification */
diff --git a/tools/aapt/Main.cpp b/tools/aapt/Main.cpp
index 739b01f..266a02f 100644
--- a/tools/aapt/Main.cpp
+++ b/tools/aapt/Main.cpp
@@ -160,7 +160,11 @@
         "       product variants\n"
         "   --utf16\n"
         "       changes default encoding for resources to UTF-16.  Only useful when API\n"
-        "       level is set to 7 or higher where the default encoding is UTF-8.\n");
+        "       level is set to 7 or higher where the default encoding is UTF-8.\n"
+        "   --non-constant-id\n"
+        "       Make the resources ID non constant. This is required to make an R java class\n"
+        "       that does not contain the final value but is used to make reusable compiled\n"
+        "       libraries that need to access resources.\n");
 }
 
 /*
@@ -497,6 +501,8 @@
                         goto bail;
                     }
                     bundle.setProduct(argv[0]);
+                } else if (strcmp(cp, "-non-constant-id") == 0) {
+                    bundle.setNonConstantId(true);
                 } else {
                     fprintf(stderr, "ERROR: Unknown option '-%s'\n", cp);
                     wantUsage = true;
diff --git a/tools/aapt/Resource.cpp b/tools/aapt/Resource.cpp
index c8ba904..0a4f24f 100644
--- a/tools/aapt/Resource.cpp
+++ b/tools/aapt/Resource.cpp
@@ -1655,7 +1655,8 @@
 
 static status_t writeSymbolClass(
     FILE* fp, const sp<AaptAssets>& assets, bool includePrivate,
-    const sp<AaptSymbols>& symbols, const String8& className, int indent)
+    const sp<AaptSymbols>& symbols, const String8& className, int indent,
+    bool nonConstantId)
 {
     fprintf(fp, "%spublic %sfinal class %s {\n",
             getIndentSpace(indent),
@@ -1665,6 +1666,10 @@
     size_t i;
     status_t err = NO_ERROR;
 
+    const char * id_format = nonConstantId ?
+            "%spublic static int %s=0x%08x;\n" :
+            "%spublic static final int %s=0x%08x;\n";
+
     size_t N = symbols->getSymbols().size();
     for (i=0; i<N; i++) {
         const AaptSymbolEntry& sym = symbols->getSymbols().valueAt(i);
@@ -1717,7 +1722,7 @@
         if (deprecated) {
             fprintf(fp, "%s@Deprecated\n", getIndentSpace(indent));
         }
-        fprintf(fp, "%spublic static final int %s=0x%08x;\n",
+        fprintf(fp, id_format,
                 getIndentSpace(indent),
                 String8(name).string(), (int)sym.int32Val);
     }
@@ -1768,7 +1773,7 @@
         if (nclassName == "styleable") {
             styleableSymbols = nsymbols;
         } else {
-            err = writeSymbolClass(fp, assets, includePrivate, nsymbols, nclassName, indent);
+            err = writeSymbolClass(fp, assets, includePrivate, nsymbols, nclassName, indent, nonConstantId);
         }
         if (err != NO_ERROR) {
             return err;
@@ -1839,7 +1844,7 @@
         "\n"
         "package %s;\n\n", package.string());
 
-        status_t err = writeSymbolClass(fp, assets, includePrivate, symbols, className, 0);
+        status_t err = writeSymbolClass(fp, assets, includePrivate, symbols, className, 0, bundle->getNonConstantId());
         if (err != NO_ERROR) {
             return err;
         }