// FULL EXAMPLE FOR RETROFIT
//add Retrofit dependencies to gradle file
//file build.gradele
implementation 'com.squareup.retrofit2:retrofit:2.9.0'
implementation 'com.squareup.retrofit2:converter-gson:2.9.0'
implementation 'com.squareup.okhttp3:okhttp:5.0.0-alpha.10'
// create an interface for more flexibility
// file MyAPI.kt
interface MyAPI(){
// function calling to server
// @Field("your_name_of_field") under this name we will receive our request on the server
// Like if(isset($_POST("your_name_of_field"))){ do something } //PHP
@FormUrlEncoded // required annotation
@POST("server.php") // address of the page to which we send data and from which we receive a response
fun SendAndGetPost(
@Field("name") userName: String?
@Field("password") userPass: String?
):Call<ResponsedData?>? // class ResponsedData.kt
companion object{
private val client = OkHttpClient.Builder().build()
operator fun invoke():MyAPI{
return Retrofit.Builder()
// https://google.com/folder/ (path example)
.baseUrl("https://yor_server_path/")
.addConverterFactory(GsonConverterFactory.create())
.client(client)
.build()
.create(MyAPI::class.java)
}
}
}
// create a class to receive our response from the server
// file ResponsedData.kt
class ResponsedData{
val email: String? = null
val age: String? = null
//variable names must match the names sent from the server !
}
// ActivityMain calls the function and get the data
class ActivityMain : AppCompatActivity(){
override fun onCreate(savedInstance: Bundle){
super.onCreate(savedInstance)
setContentView(R.layout.activity_main)
val name = "myName"
val password = "1234567"
MyAPI().SendAndGetPost(name, password)?enqueue(
object: CalBack<ResponsedData?>{
override fun onResponse(
call: Call<ResponsedData?>,
response: Response<ResponsedData?>)
{
if(!response.isSuccessful){
Log.e("API-ERROR", response.code().toString())
return
}else{
// val answer: ResponsedData
val answer = response.body()
email.name
age.password
// data for use
}
}
override fun onFalure(
call: Call<ResponsedData?>,
t: Throwable)
{
Log.e("API-ERROR", t.printStackTrace())
}
})
}
}
--------------------- SERVER SIDE -------------------------------------------
// this is how the file on the server looks like
// the path to which we registered in the interface of our application
// file server.php
<?php
// Data Base includes
// or any sources
if(isset($_POST("name")) && isset($_POST("password"))){
$js = array(
'email'=>"some data from DB",
'age'=>"some data from DB"
);
echo json_encode($js);
exit();
}
// all examples are taken from here
// https://square.github.io/retrofit/
public interface MyApiEndpointInterface {
// Request method and URL specified in the annotation
// Callback for the parsed response is the last parameter
@GET("users/{username}")
void getUser(@Path("username") String username, Callback<User> cb);
@GET("group/{id}/users")
void groupList(@Path("id") int groupId, @Query("sort") String sort, Callback<List<User>> cb);
@POST("users/new")
void createUser(@Body User user, Callback<User> cb);
}
// Trailing slash is needed
public static final String BASE_URL = "http://api.myservice.com/";
Retrofit retrofit = new Retrofit.Builder()
.baseUrl(BASE_URL)
.addConverterFactory(GsonConverterFactory.create())
.build();