Just googling around and find useful Java library, okhttp3, to send http request in from Android app.
Here I share the codes demonstrating how to use that library.
Android App Manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.zofiakreasi.simplerequest">
<uses-permission android:name="android.permission.INTERNET"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
activity_main:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.zofiakreasi.simplerequest.MainActivity">
<TextView
android:id="@+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:text="TextView"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="@+id/buttonSimple"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="8dp"
android:layout_marginStart="8dp"
android:text="Simple Request"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent" />
<Button
android:id="@+id/buttonGet"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="8dp"
android:layout_marginStart="8dp"
android:text="GET Request"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toEndOf="@+id/buttonSimple" />
</android.support.constraint.ConstraintLayout>
Main Activity:
package com.zofiakreasi.simplerequest;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.io.IOException;
import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.MediaType;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
public class MainActivity extends AppCompatActivity {
TextView mTextView;
String url = "";
Button buttonSimple;
Button buttonGet;
public static final MediaType JSON = MediaType.parse("application/json; charset=utf-8");
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTextView = findViewById(R.id.text);
buttonSimple = findViewById(R.id.buttonSimple);
buttonSimple.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
simpleReq();
}
});
buttonGet = findViewById(R.id.buttonGet);
buttonGet.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
getReq();
}
});
}
void simpleReq(){
mTextView.setText("Please wait...");
url = "URL HERE";
try {
runSimpleReq();
} catch (IOException e) {
e.printStackTrace();
}
}
void getReq(){
mTextView.setText("Please wait...");
url = "URL HERE";
try {
runSimpleReq();
} catch (IOException e) {
e.printStackTrace();
}
}
void runSimpleReq() throws IOException {
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url(url)
.build();
client.newCall(request).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
call.cancel();
}
@Override
public void onResponse(Call call, Response response) throws IOException {
final String myResponse = response.body().string();
MainActivity.this.runOnUiThread(new Runnable() {
@Override
public void run() {
mTextView.setText(myResponse);
}
});
}
});
}
}
Don’t forget to include this dependency in your Gradle file:
compile 'com.squareup.okhttp3:okhttp:3.7.0'