feature: enable to set android min api (#295)

* Add androidMinApi parameter to gradle plugin to enable specify --min-api argument of d8 tool

* Add all dex files to main dex jar

Author: piiertho

docs/src/doc/user-guide/exporting.md

@@ -63,6 +63,13 @@ On android, we do not embed a JVM, we use the existing ART provided by the OS. I
     }
     ```
 
+- Setting the `androidMinApi` (equivalent to `--min-api` argument of `d8` tool), default is `21`:
+    ```kt
+    godot {
+        androidMinApi = 22
+    }
+    ```
+
 !!! warning
     Similar to the desktop targets, the game copies the needed jar files to the `user://` directory upon first execution or if the files have changed. On android this is the applications `files` folder. If you do IO operations on Android, never empty the whole `files` folder! Only delete what you have added or exclude the following two files when clearing the `files` folder: `godot-bootstrap-dex.jar` and `main-dex.jar`.
 

kt/plugins/godot-gradle-plugin/src/main/kotlin/godot/gradle/GodotExtension.kt

@@ -26,6 +26,13 @@ open class GodotExtension(objects: ObjectFactory) {
      */
     var androidCompileSdkDir = objects.fileProperty()
 
+    /**
+     * Min android api version.
+     *
+     * example: 21
+     */
+    var androidMinApi = objects.property(Int::class.java)
+
     /**
      * enable Graal Native Image Export
      *
@@ -88,6 +95,8 @@ open class GodotExtension(objects: ObjectFactory) {
             androidCompileSdkDir.set(androidCompileSdkDirFile)
         }
 
+        androidMinApi.set(21)
+
         isGraalNativeImageExportEnabled.set(false)
         nativeImageToolPath.set(System.getenv("native-image")?.let { File(it) })
         additionalGraalJniConfigurationFiles.set(arrayOf())

kt/plugins/godot-gradle-plugin/src/main/kotlin/godot/gradle/tasks/android/createMainDexFileTask.kt

@@ -40,6 +40,8 @@ fun Project.createMainDexFileTask(
                         mainJar.absolutePath,
                         "--lib",
                         "${godotJvmExtension.androidCompileSdkDir.get().asFile.absolutePath}${File.separator}android.jar",
+                        "--min-api",
+                        godotJvmExtension.androidMinApi.get(),
                     )
                 } else {
                     commandLine(
@@ -49,6 +51,8 @@ fun Project.createMainDexFileTask(
                         "${godotJvmExtension.androidCompileSdkDir.get().asFile.absolutePath}/android.jar",
                         "--classpath",
                         godotBootstrapJar.absolutePath,
+                        "--min-api",
+                        godotJvmExtension.androidMinApi.get(),
                     )
                 }
             }

kt/plugins/godot-gradle-plugin/src/main/kotlin/godot/gradle/tasks/android/packageBootstrapDexJarTask.kt

@@ -36,6 +36,8 @@ fun Project.packageBootstrapDexJarTask(
                         "godot-bootstrap-dex.jar",
                         "--lib",
                         "${godotJvmExtension.androidCompileSdkDir.get().asFile.absolutePath}${File.separator}android.jar",
+                        "--min-api",
+                        godotJvmExtension.androidMinApi.get(),
                     )
                 } else {
                     commandLine(
@@ -45,6 +47,8 @@ fun Project.packageBootstrapDexJarTask(
                         "godot-bootstrap-dex.jar",
                         "--lib",
                         "${godotJvmExtension.androidCompileSdkDir.get().asFile.absolutePath}/android.jar",
+                        "--min-api",
+                        godotJvmExtension.androidMinApi.get(),
                     )
                 }
             }

kt/plugins/godot-gradle-plugin/src/main/kotlin/godot/gradle/tasks/android/packageMainDexJarTask.kt

@@ -17,7 +17,7 @@ fun Project.packageMainDexJarTask(
             archiveBaseName.set("main-dex")
 
             from("src/main/resources").include("**/godot.runtime.Entry")
-            from("${project.buildDir.absolutePath}/libs/").include("classes.dex")
+            from("${project.buildDir.absolutePath}/libs/").include("*.dex")
 
             dependsOn(createMainDexFileTask)
         }