implemented shared preferences

android/app/build.gradle

@@ -8,15 +8,15 @@ plugins {
 android {
     namespace = "com.example.flutter_android_app"
     compileSdk = flutter.compileSdkVersion
-    ndkVersion = flutter.ndkVersion
+    ndkVersion "25.1.8937393"
 
     compileOptions {
-        sourceCompatibility = JavaVersion.VERSION_1_8
-        targetCompatibility = JavaVersion.VERSION_1_8
+        sourceCompatibility = JavaVersion.VERSION_17
+        targetCompatibility = JavaVersion.VERSION_17
     }
 
     kotlinOptions {
-        jvmTarget = JavaVersion.VERSION_1_8
+        jvmTarget = 17
     }
 
     defaultConfig {