android fixes for mods and saves (#297)

mobile/android/love/src/jni/love/src/common/android.cpp

@@ -183,13 +183,37 @@ void vibrate(double seconds)
 	env->DeleteLocalRef(activity);
 }
 
-bool showFilePicker()
+bool showFilePicker(const char *destFilename)
 {
+	if (destFilename == nullptr || destFilename[0] == '\0')
+		destFilename = "picked_rom.gb";
+
 	JNIEnv *env = (JNIEnv*) SDL_AndroidGetJNIEnv();
 	jclass activity = env->FindClass("org/love2d/android/GameActivity");
 
-	jmethodID method = env->GetStaticMethodID(activity, "showRomFilePicker", "()Z");
-	jboolean result = env->CallStaticBooleanMethod(activity, method);
+	jmethodID method = env->GetStaticMethodID(activity, "showFilePicker",
+		"(Ljava/lang/String;)Z");
+	jstring jname = env->NewStringUTF(destFilename);
+	jboolean result = env->CallStaticBooleanMethod(activity, method, jname);
+	env->DeleteLocalRef(jname);
+
+	env->DeleteLocalRef(activity);
+	return result;
+}
+
+bool showCreateDocument(const char *suggestedName)
+{
+	if (suggestedName == nullptr || suggestedName[0] == '\0')
+		suggestedName = "export.sav";
+
+	JNIEnv *env = (JNIEnv*) SDL_AndroidGetJNIEnv();
+	jclass activity = env->FindClass("org/love2d/android/GameActivity");
+
+	jmethodID method = env->GetStaticMethodID(activity, "showCreateDocument",
+		"(Ljava/lang/String;)Z");
+	jstring jname = env->NewStringUTF(suggestedName);
+	jboolean result = env->CallStaticBooleanMethod(activity, method, jname);
+	env->DeleteLocalRef(jname);
 
 	env->DeleteLocalRef(activity);
 	return result;

mobile/android/love/src/jni/love/src/common/android.h

@@ -63,9 +63,16 @@ void vibrate(double seconds);
  * Shows the system's "pick a document" UI (Storage Access Framework).
  * Returns true if the picker was launched; the picked file (if any) is
  * copied asynchronously by GameActivity.onActivityResult into the app's
- * external save directory, not returned here -- see src/import/RomImporter.lua.
+ * external save directory under destFilename (default picked_rom.gb), not
+ * returned here -- see src/import/RomImporter.lua.
  **/
-bool showFilePicker();
+bool showFilePicker(const char *destFilename = nullptr);
+
+/**
+ * Shows ACTION_CREATE_DOCUMENT so Lua can export a staged pending_export.sav
+ * to a user-chosen location. suggestedName is the dialog default filename.
+ **/
+bool showCreateDocument(const char *suggestedName = nullptr);
 
 /*
  * Helper functions for the filesystem module

mobile/android/love/src/jni/love/src/modules/system/System.cpp

@@ -22,6 +22,8 @@
 #include "common/config.h"
 #include "System.h"
 
+#include <cstring>
+
 #if defined(LOVE_MACOSX)
 #include <CoreServices/CoreServices.h>
 #elif defined(LOVE_IOS)
@@ -180,11 +182,32 @@ void System::vibrate(double seconds) const
 #endif
 }
 
-bool System::pickFile() const
+bool System::pickFile(const char *kind) const
 {
 #ifdef LOVE_ANDROID
-	return love::android::showFilePicker();
+	const char *dest = "picked_rom.gb";
+	if (kind != nullptr)
+	{
+		if (strcmp(kind, "mod") == 0)
+			dest = "picked_mod.zip";
+		else if (strcmp(kind, "sav") == 0 || strcmp(kind, "save") == 0)
+			dest = "picked_save.sav";
+		else if (strcmp(kind, "rom") == 0)
+			dest = "picked_rom.gb";
+	}
+	return love::android::showFilePicker(dest);
 #else
+	LOVE_UNUSED(kind);
+	return false;
+#endif
+}
+
+bool System::createFile(const char *suggestedName) const
+{
+#ifdef LOVE_ANDROID
+	return love::android::showCreateDocument(suggestedName);
+#else
+	LOVE_UNUSED(suggestedName);
 	return false;
 #endif
 }

mobile/android/love/src/jni/love/src/modules/system/System.h

@@ -111,9 +111,21 @@ public:
 	 * Android only for now; the result (if any) is not returned here -- see
 	 * love::android::showFilePicker and src/import/RomImporter.lua.
 	 *
+	 * @param kind Optional pick kind: nullptr/"rom" -> picked_rom.gb,
+	 *             "mod" -> picked_mod.zip, "sav"/"save" -> picked_save.sav.
 	 * @return Whether the picker was shown.
 	 **/
-	virtual bool pickFile() const;
+	virtual bool pickFile(const char *kind = nullptr) const;
+
+	/**
+	 * Shows the platform's native "create / save a file" UI (Android SAF
+	 * ACTION_CREATE_DOCUMENT). Copies staged pending_export.sav from the app
+	 * save directory to the user-chosen URI. See GameActivity.showCreateDocument.
+	 *
+	 * @param suggestedName Default filename shown in the dialog.
+	 * @return Whether the create dialog was shown.
+	 **/
+	virtual bool createFile(const char *suggestedName = nullptr) const;
 
 	/**
 	 * Gets if the user is playing music on background.

mobile/android/love/src/jni/love/src/modules/system/wrap_System.cpp

@@ -97,7 +97,15 @@ int w_vibrate(lua_State *L)
 
 int w_pickFile(lua_State *L)
 {
-	luax_pushboolean(L, instance()->pickFile());
+	const char *kind = luaL_optstring(L, 1, nullptr);
+	luax_pushboolean(L, instance()->pickFile(kind));
+	return 1;
+}
+
+int w_createFile(lua_State *L)
+{
+	const char *suggested = luaL_optstring(L, 1, nullptr);
+	luax_pushboolean(L, instance()->createFile(suggested));
 	return 1;
 }
 
@@ -117,6 +125,7 @@ static const luaL_Reg functions[] =
 	{ "openURL", w_openURL },
 	{ "vibrate", w_vibrate },
 	{ "pickFile", w_pickFile },
+	{ "createFile", w_createFile },
 	{ "hasBackgroundMusic", w_hasBackgroundMusic },
 	{ 0, 0 }
 };