starting example and improved SerialPortBuilder

2018-11-10 02:39:55 +01:00 · 2018-11-10 02:39:55 +01:00 · 274cf71f62
commit 274cf71f62
--- a/examplemultipleports/.gitignore
+++ b/examplemultipleports/.gitignore
@ -0,0 +1 @@
+/build
--- a/examplemultipleports/build.gradle
+++ b/examplemultipleports/build.gradle
@ -0,0 +1,36 @@
+apply plugin: 'com.android.application'
+
+android {
+    compileSdkVersion 28
+
+
+
+    defaultConfig {
+        applicationId "com.felhr.examplemultipleports"
+        minSdkVersion 17
+        targetSdkVersion 28
+        versionCode 1
+        versionName "1.0"
+
+        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+
+    }
+
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+        }
+    }
+
+}
+
+dependencies {
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+
+    implementation 'com.android.support:appcompat-v7:28.0.0'
+    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
+    testImplementation 'junit:junit:4.12'
+    androidTestImplementation 'com.android.support.test:runner:1.0.2'
+    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
+}
--- a/examplemultipleports/proguard-rules.pro
+++ b/examplemultipleports/proguard-rules.pro
@ -0,0 +1,21 @@
+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile
--- a/examplemultipleports/src/androidTest/java/com/felhr/examplemultipleports/ExampleInstrumentedTest.java
+++ b/examplemultipleports/src/androidTest/java/com/felhr/examplemultipleports/ExampleInstrumentedTest.java
@ -0,0 +1,26 @@
+package com.felhr.examplemultipleports;
+
+import android.content.Context;
+import android.support.test.InstrumentationRegistry;
+import android.support.test.runner.AndroidJUnit4;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import static org.junit.Assert.*;
+
+/**
+ * Instrumented test, which will execute on an Android device.
+ *
+ * @see <a href="http://d.android.com/tools/testing">Testing documentation</a>
+ */
+@RunWith(AndroidJUnit4.class)
+public class ExampleInstrumentedTest {
+    @Test
+    public void useAppContext() {
+        // Context of the app under test.
+        Context appContext = InstrumentationRegistry.getTargetContext();
+
+        assertEquals("com.felhr.examplemultipleports", appContext.getPackageName());
+    }
+}
--- a/examplemultipleports/src/main/AndroidManifest.xml
+++ b/examplemultipleports/src/main/AndroidManifest.xml
@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest package="com.felhr.examplemultipleports"
+          xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <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>
--- a/examplemultipleports/src/main/java/com/felhr/examplemultipleports/MainActivity.java
+++ b/examplemultipleports/src/main/java/com/felhr/examplemultipleports/MainActivity.java
@ -0,0 +1,172 @@
+package com.felhr.examplemultipleports;
+
+import android.content.BroadcastReceiver;
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.content.ServiceConnection;
+import android.os.Handler;
+import android.os.IBinder;
+import android.os.Message;
+import android.support.v7.app.AppCompatActivity;
+import android.os.Bundle;
+import android.view.View;
+import android.widget.Button;
+import android.widget.CheckBox;
+import android.widget.CompoundButton;
+import android.widget.EditText;
+import android.widget.TextView;
+import android.widget.Toast;
+
+import java.lang.ref.WeakReference;
+import java.util.Set;
+
+public class MainActivity extends AppCompatActivity {
+
+
+    /*
+     * Notifications from UsbService will be received here.
+     */
+    private final BroadcastReceiver mUsbReceiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            switch (intent.getAction()) {
+                case UsbService.ACTION_USB_PERMISSION_GRANTED: // USB PERMISSION GRANTED
+                    Toast.makeText(context, "USB Ready", Toast.LENGTH_SHORT).show();
+                    break;
+                case UsbService.ACTION_USB_PERMISSION_NOT_GRANTED: // USB PERMISSION NOT GRANTED
+                    Toast.makeText(context, "USB Permission not granted", Toast.LENGTH_SHORT).show();
+                    break;
+                case UsbService.ACTION_NO_USB: // NO USB CONNECTED
+                    Toast.makeText(context, "No USB connected", Toast.LENGTH_SHORT).show();
+                    break;
+                case UsbService.ACTION_USB_DISCONNECTED: // USB DISCONNECTED
+                    Toast.makeText(context, "USB disconnected", Toast.LENGTH_SHORT).show();
+                    break;
+                case UsbService.ACTION_USB_NOT_SUPPORTED: // USB NOT SUPPORTED
+                    Toast.makeText(context, "USB device not supported", Toast.LENGTH_SHORT).show();
+                    break;
+            }
+        }
+    };
+    private UsbService usbService;
+    private TextView display1, display2;
+    private EditText editText1, editText2;
+    private Button button1, button2;
+    private MyHandler mHandler;
+    private final ServiceConnection usbConnection = new ServiceConnection() {
+        @Override
+        public void onServiceConnected(ComponentName arg0, IBinder arg1) {
+            usbService = ((UsbService.UsbBinder) arg1).getService();
+            usbService.setHandler(mHandler);
+        }
+
+        @Override
+        public void onServiceDisconnected(ComponentName arg0) {
+            usbService = null;
+        }
+    };
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_main);
+
+        display1 = findViewById(R.id.textView1);
+        display2 = findViewById(R.id.textView2);
+
+        editText1 = findViewById(R.id.editText1);
+        editText2 = findViewById(R.id.editText2);
+
+        button1 = findViewById(R.id.buttonSend1);
+        button2 = findViewById(R.id.buttonSend2);
+
+        button1.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View view) {
+                //TODO!!
+            }
+        });
+
+        button2.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View view) {
+                //TODO!!
+            }
+        });
+
+        mHandler = new MyHandler(this);
+    }
+
+    @Override
+    public void onResume() {
+        super.onResume();
+        setFilters();  // Start listening notifications from UsbService
+        startService(UsbService.class, usbConnection, null); // Start UsbService(if it was not started before) and Bind it
+    }
+
+    @Override
+    public void onPause() {
+        super.onPause();
+        unregisterReceiver(mUsbReceiver);
+        unbindService(usbConnection);
+    }
+
+    private void startService(Class<?> service, ServiceConnection serviceConnection, Bundle extras) {
+        if (!UsbService.SERVICE_CONNECTED) {
+            Intent startService = new Intent(this, service);
+            if (extras != null && !extras.isEmpty()) {
+                Set<String> keys = extras.keySet();
+                for (String key : keys) {
+                    String extra = extras.getString(key);
+                    startService.putExtra(key, extra);
+                }
+            }
+            startService(startService);
+        }
+        Intent bindingIntent = new Intent(this, service);
+        bindService(bindingIntent, serviceConnection, Context.BIND_AUTO_CREATE);
+    }
+
+    private void setFilters() {
+        IntentFilter filter = new IntentFilter();
+        filter.addAction(UsbService.ACTION_USB_PERMISSION_GRANTED);
+        filter.addAction(UsbService.ACTION_NO_USB);
+        filter.addAction(UsbService.ACTION_USB_DISCONNECTED);
+        filter.addAction(UsbService.ACTION_USB_NOT_SUPPORTED);
+        filter.addAction(UsbService.ACTION_USB_PERMISSION_NOT_GRANTED);
+        registerReceiver(mUsbReceiver, filter);
+    }
+
+    /*
+     * This handler will be passed to UsbService. Data received from serial port is displayed through this handler
+     */
+    private static class MyHandler extends Handler {
+        private final WeakReference<MainActivity> mActivity;
+
+        public MyHandler(MainActivity activity) {
+            mActivity = new WeakReference<>(activity);
+        }
+
+        @Override
+        public void handleMessage(Message msg) {
+            switch (msg.what) {
+                case UsbService.MESSAGE_FROM_SERIAL_PORT:
+                    String data = (String) msg.obj;
+                    //mActivity.get().display.append(data);
+                    break;
+                case UsbService.CTS_CHANGE:
+                    Toast.makeText(mActivity.get(), "CTS_CHANGE",Toast.LENGTH_LONG).show();
+                    break;
+                case UsbService.DSR_CHANGE:
+                    Toast.makeText(mActivity.get(), "DSR_CHANGE",Toast.LENGTH_LONG).show();
+                    break;
+                case UsbService.SYNC_READ:
+                    String buffer = (String) msg.obj;
+                    //mActivity.get().display.append(buffer);
+                    break;
+            }
+        }
+    }
+}
--- a/examplemultipleports/src/main/java/com/felhr/examplemultipleports/UsbService.java
+++ b/examplemultipleports/src/main/java/com/felhr/examplemultipleports/UsbService.java
@ -0,0 +1,52 @@
+package com.felhr.examplemultipleports;
+
+import android.app.Service;
+import android.content.Intent;
+import android.os.Binder;
+import android.os.Handler;
+import android.os.IBinder;
+import android.support.annotation.Nullable;
+
+/**
+ * Created by Felipe Herranz(felhr85@gmail.com) on 09/11/2018.
+ */
+public class UsbService extends Service {
+
+    public static final String ACTION_USB_READY = "com.felhr.connectivityservices.USB_READY";
+    public static final String ACTION_USB_ATTACHED = "android.hardware.usb.action.USB_DEVICE_ATTACHED";
+    public static final String ACTION_USB_DETACHED = "android.hardware.usb.action.USB_DEVICE_DETACHED";
+    public static final String ACTION_USB_NOT_SUPPORTED = "com.felhr.usbservice.USB_NOT_SUPPORTED";
+    public static final String ACTION_NO_USB = "com.felhr.usbservice.NO_USB";
+    public static final String ACTION_USB_PERMISSION_GRANTED = "com.felhr.usbservice.USB_PERMISSION_GRANTED";
+    public static final String ACTION_USB_PERMISSION_NOT_GRANTED = "com.felhr.usbservice.USB_PERMISSION_NOT_GRANTED";
+    public static final String ACTION_USB_DISCONNECTED = "com.felhr.usbservice.USB_DISCONNECTED";
+    public static final String ACTION_CDC_DRIVER_NOT_WORKING = "com.felhr.connectivityservices.ACTION_CDC_DRIVER_NOT_WORKING";
+    public static final String ACTION_USB_DEVICE_NOT_WORKING = "com.felhr.connectivityservices.ACTION_USB_DEVICE_NOT_WORKING";
+    public static final int MESSAGE_FROM_SERIAL_PORT = 0;
+    public static final int CTS_CHANGE = 1;
+    public static final int DSR_CHANGE = 2;
+    public static final int SYNC_READ = 3;
+    private static final String ACTION_USB_PERMISSION = "com.android.example.USB_PERMISSION";
+    private static final int BAUD_RATE = 9600; // BaudRate. Change this value if you need
+    public static boolean SERVICE_CONNECTED = false;
+
+    private IBinder binder = new UsbBinder();
+
+    private Handler mHandler;
+
+    @Nullable
+    @Override
+    public IBinder onBind(Intent intent) {
+        return binder;
+    }
+
+    public void setHandler(Handler mHandler) {
+        this.mHandler = mHandler;
+    }
+
+    public class UsbBinder extends Binder {
+        public UsbService getService() {
+            return UsbService.this;
+        }
+    }
+}
--- a/examplemultipleports/src/main/res/drawable-v24/ic_launcher_foreground.xml
+++ b/examplemultipleports/src/main/res/drawable-v24/ic_launcher_foreground.xml
@ -0,0 +1,34 @@
+<vector xmlns:aapt="http://schemas.android.com/aapt"
+        xmlns:android="http://schemas.android.com/apk/res/android"
+        android:width="108dp"
+        android:height="108dp"
+        android:viewportHeight="108"
+        android:viewportWidth="108">
+    <path
+        android:fillType="evenOdd"
+        android:pathData="M32,64C32,64 38.39,52.99 44.13,50.95C51.37,48.37 70.14,49.57 70.14,49.57L108.26,87.69L108,109.01L75.97,107.97L32,64Z"
+        android:strokeColor="#00000000"
+        android:strokeWidth="1">
+        <aapt:attr name="android:fillColor">
+            <gradient
+                android:endX="78.5885"
+                android:endY="90.9159"
+                android:startX="48.7653"
+                android:startY="61.0927"
+                android:type="linear">
+                <item
+                    android:color="#44000000"
+                    android:offset="0.0"/>
+                <item
+                    android:color="#00000000"
+                    android:offset="1.0"/>
+            </gradient>
+        </aapt:attr>
+    </path>
+    <path
+        android:fillColor="#FFFFFF"
+        android:fillType="nonZero"
+        android:pathData="M66.94,46.02L66.94,46.02C72.44,50.07 76,56.61 76,64L32,64C32,56.61 35.56,50.11 40.98,46.06L36.18,41.19C35.45,40.45 35.45,39.3 36.18,38.56C36.91,37.81 38.05,37.81 38.78,38.56L44.25,44.05C47.18,42.57 50.48,41.71 54,41.71C57.48,41.71 60.78,42.57 63.68,44.05L69.11,38.56C69.84,37.81 70.98,37.81 71.71,38.56C72.44,39.3 72.44,40.45 71.71,41.19L66.94,46.02ZM62.94,56.92C64.08,56.92 65,56.01 65,54.88C65,53.76 64.08,52.85 62.94,52.85C61.8,52.85 60.88,53.76 60.88,54.88C60.88,56.01 61.8,56.92 62.94,56.92ZM45.06,56.92C46.2,56.92 47.13,56.01 47.13,54.88C47.13,53.76 46.2,52.85 45.06,52.85C43.92,52.85 43,53.76 43,54.88C43,56.01 43.92,56.92 45.06,56.92Z"
+        android:strokeColor="#00000000"
+        android:strokeWidth="1"/>
+</vector>
--- a/examplemultipleports/src/main/res/drawable/ic_launcher_background.xml
+++ b/examplemultipleports/src/main/res/drawable/ic_launcher_background.xml
@ -0,0 +1,171 @@
+<?xml version="1.0" encoding="utf-8"?>
+<vector
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportHeight="108"
+    android:viewportWidth="108">
+    <path
+        android:fillColor="#008577"
+        android:pathData="M0,0h108v108h-108z"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M9,0L9,108"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,0L19,108"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,0L29,108"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,0L39,108"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,0L49,108"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,0L59,108"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,0L69,108"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,0L79,108"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M89,0L89,108"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M99,0L99,108"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,9L108,9"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,19L108,19"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,29L108,29"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,39L108,39"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,49L108,49"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,59L108,59"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,69L108,69"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,79L108,79"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,89L108,89"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,99L108,99"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,29L89,29"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,39L89,39"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,49L89,49"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,59L89,59"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,69L89,69"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,79L89,79"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,19L29,89"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,19L39,89"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,19L49,89"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,19L59,89"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,19L69,89"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,19L79,89"
+        android:strokeColor="#33FFFFFF"
+        android:strokeWidth="0.8"/>
+</vector>
--- a/examplemultipleports/src/main/res/layout/activity_main.xml
+++ b/examplemultipleports/src/main/res/layout/activity_main.xml
@ -0,0 +1,94 @@
+<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+                xmlns:tools="http://schemas.android.com/tools"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                tools:context="com.felhr.examplemultipleports.MainActivity">
+
+    <TextView
+        android:id="@+id/textViewTitle1"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_alignParentTop="true"
+        android:layout_centerHorizontal="true"
+        android:text="Multiple Serial Ports"
+        android:textAppearance="?android:attr/textAppearanceLarge"/>
+
+    <TextView
+        android:id="@+id/textView1"
+        android:layout_width="match_parent"
+        android:layout_height="150dp"
+        android:layout_centerHorizontal="true"
+        android:layout_marginTop="34dp"
+        android:background="#000000"
+        android:textColor="#FFFFFF"
+        android:scrollbars="vertical"
+        android:text="COM1: "
+        android:gravity="bottom" />
+
+    <TextView
+        android:id="@+id/textView2"
+        android:layout_width="match_parent"
+        android:layout_height="150dp"
+        android:layout_centerHorizontal="true"
+        android:layout_marginTop="10dp"
+        android:background="#000000"
+        android:layout_below="@+id/textView1"
+        android:textColor="#FFFFFF"
+        android:text="COM2: "
+        android:scrollbars="vertical"
+        android:gravity="bottom" />
+
+    <EditText
+        android:id="@+id/editText1"
+        android:layout_width="227dp"
+        android:layout_height="wrap_content"
+        android:layout_alignLeft="@+id/textView1"
+        android:layout_alignRight="@+id/textView1"
+        android:layout_below="@+id/textView2"
+        android:layout_marginRight="184dp"
+        android:layout_marginTop="28dp"
+        android:ems="10">
+    </EditText>
+
+    <Button
+        android:id="@+id/buttonSend1"
+        style="?borderlessButtonStyle"
+        android:layout_width="178dp"
+        android:layout_height="48dp"
+        android:layout_alignLeft="@+id/editText1"
+        android:layout_alignRight="@+id/editText1"
+        android:layout_below="@+id/editText1"
+        android:layout_marginLeft="227dp"
+        android:layout_marginRight="-175dp"
+        android:layout_marginTop="-48dp"
+        android:textSize="10sp"
+        android:background="@color/colorAccent"
+        android:text="Send through COM1"/>
+
+    <EditText
+        android:id="@+id/editText2"
+        android:layout_width="227dp"
+        android:layout_height="wrap_content"
+        android:layout_alignLeft="@+id/textView1"
+        android:layout_alignRight="@+id/textView1"
+        android:layout_below="@+id/editText1"
+        android:layout_marginRight="184dp"
+        android:layout_marginTop="28dp"
+        android:ems="10">
+    </EditText>
+
+    <Button
+        android:id="@+id/buttonSend2"
+        style="?borderlessButtonStyle"
+        android:layout_width="178dp"
+        android:layout_height="48dp"
+        android:layout_alignLeft="@+id/editText2"
+        android:layout_alignRight="@+id/editText2"
+        android:layout_below="@+id/editText2"
+        android:layout_marginLeft="227dp"
+        android:layout_marginRight="-175dp"
+        android:layout_marginTop="-48dp"
+        android:textSize="10sp"
+        android:background="@color/colorAccent"
+        android:text="Send through COM2"/>
+</RelativeLayout>
--- a/examplemultipleports/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
+++ b/examplemultipleports/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@drawable/ic_launcher_background"/>
+    <foreground android:drawable="@drawable/ic_launcher_foreground"/>
+</adaptive-icon>
--- a/examplemultipleports/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml
+++ b/examplemultipleports/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml
@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@drawable/ic_launcher_background"/>
+    <foreground android:drawable="@drawable/ic_launcher_foreground"/>
+</adaptive-icon>
--- a/examplemultipleports/src/main/res/mipmap-hdpi/ic_launcher.png
+++ b/examplemultipleports/src/main/res/mipmap-hdpi/ic_launcher.png
--- a/examplemultipleports/src/main/res/mipmap-hdpi/ic_launcher_round.png
+++ b/examplemultipleports/src/main/res/mipmap-hdpi/ic_launcher_round.png
--- a/examplemultipleports/src/main/res/mipmap-mdpi/ic_launcher.png
+++ b/examplemultipleports/src/main/res/mipmap-mdpi/ic_launcher.png
--- a/examplemultipleports/src/main/res/mipmap-mdpi/ic_launcher_round.png
+++ b/examplemultipleports/src/main/res/mipmap-mdpi/ic_launcher_round.png
--- a/examplemultipleports/src/main/res/mipmap-xhdpi/ic_launcher.png
+++ b/examplemultipleports/src/main/res/mipmap-xhdpi/ic_launcher.png
--- a/examplemultipleports/src/main/res/mipmap-xhdpi/ic_launcher_round.png
+++ b/examplemultipleports/src/main/res/mipmap-xhdpi/ic_launcher_round.png
--- a/examplemultipleports/src/main/res/mipmap-xxhdpi/ic_launcher.png
+++ b/examplemultipleports/src/main/res/mipmap-xxhdpi/ic_launcher.png
--- a/examplemultipleports/src/main/res/mipmap-xxhdpi/ic_launcher_round.png
+++ b/examplemultipleports/src/main/res/mipmap-xxhdpi/ic_launcher_round.png
--- a/examplemultipleports/src/main/res/mipmap-xxxhdpi/ic_launcher.png
+++ b/examplemultipleports/src/main/res/mipmap-xxxhdpi/ic_launcher.png
--- a/examplemultipleports/src/main/res/mipmap-xxxhdpi/ic_launcher_round.png
+++ b/examplemultipleports/src/main/res/mipmap-xxxhdpi/ic_launcher_round.png
--- a/examplemultipleports/src/main/res/values/colors.xml
+++ b/examplemultipleports/src/main/res/values/colors.xml
@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="colorPrimary">#008577</color>
+    <color name="colorPrimaryDark">#00574B</color>
+    <color name="colorAccent">#D81B60</color>
+</resources>
--- a/examplemultipleports/src/main/res/values/strings.xml
+++ b/examplemultipleports/src/main/res/values/strings.xml
@ -0,0 +1,3 @@
+<resources>
+    <string name="app_name">Example multiple ports</string>
+</resources>
--- a/examplemultipleports/src/main/res/values/styles.xml
+++ b/examplemultipleports/src/main/res/values/styles.xml
@ -0,0 +1,11 @@
+<resources>
+
+    <!-- Base application theme. -->
+    <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
+        <!-- Customize your theme here. -->
+        <item name="colorPrimary">@color/colorPrimary</item>
+        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
+        <item name="colorAccent">@color/colorAccent</item>
+    </style>
+
+</resources>
--- a/examplemultipleports/src/test/java/com/felhr/examplemultipleports/ExampleUnitTest.java
+++ b/examplemultipleports/src/test/java/com/felhr/examplemultipleports/ExampleUnitTest.java
@ -0,0 +1,17 @@
+package com.felhr.examplemultipleports;
+
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+/**
+ * Example local unit test, which will execute on the development machine (host).
+ *
+ * @see <a href="http://d.android.com/tools/testing">Testing documentation</a>
+ */
+public class ExampleUnitTest {
+    @Test
+    public void addition_isCorrect() {
+        assertEquals(4, 2 + 2);
+    }
+}
--- a/settings.gradle
+++ b/settings.gradle
@ -1 +1 @@
-include ':usbserial', ':example', ':examplesync', ':examplestreams'
+include ':usbserial', ':example', ':examplesync', ':examplestreams', ':examplemultipleports'
--- a/usbserial/src/main/java/com/felhr/usbserial/SerialPortBuilder.java
+++ b/usbserial/src/main/java/com/felhr/usbserial/SerialPortBuilder.java
@ -7,8 +7,8 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.hardware.usb.UsbDevice;
+import android.hardware.usb.UsbDeviceConnection;
 import android.hardware.usb.UsbManager;
-import android.os.Handler;

 import com.annimon.stream.Stream;

@ -23,7 +23,7 @@ public class SerialPortBuilder {

    private static SerialPortBuilder SerialPortBuilder;

-    private List<UsbDevice> devices;
+    private List<UsbDeviceStatus> devices;
    private List<UsbSerialDevice> serialDevices = new ArrayList<>();

    private int index = 0;
@ -53,14 +53,23 @@ public class SerialPortBuilder {

    public List<UsbDevice> getPossibleSerialPorts(){
        HashMap<String, UsbDevice> allDevices = usbManager.getDeviceList();
-
-        return Stream.of(allDevices.values()).filter(
-                p -> UsbSerialDevice.isSupported(p))
+        return Stream.of(allDevices.values())
+                .filter(UsbSerialDevice::isSupported)
                .toList();
    }

    public boolean getSerialPorts(Context context){
-        devices = getPossibleSerialPorts();
+
+        if(devices == null) {
+            devices = Stream.of(getPossibleSerialPorts())
+                    .map(UsbDeviceStatus::new)
+                    .toList();
+        }else{
+            devices.addAll(Stream.of(getPossibleSerialPorts())
+                    .map(UsbDeviceStatus::new)
+                    .filter(p -> !devices.contains(p))
+                    .toList());
+        }

        if(devices == null || devices.size() == 0)
            return false;
@ -84,9 +93,18 @@ public class SerialPortBuilder {
        return getSerialPorts(context);
    }

-    private void requestPermission(Context context){
-        PendingIntent mPendingIntent = PendingIntent.getBroadcast(context, 0, new Intent(ACTION_USB_PERMISSION), 0);
-        usbManager.requestPermission(devices.get(index), mPendingIntent);
+    private boolean requestPermission(Context context){
+        if(!devices.get(index).open) {
+            PendingIntent mPendingIntent = PendingIntent.getBroadcast(context, 0, new Intent(ACTION_USB_PERMISSION), 0);
+            usbManager.requestPermission(devices.get(index).usbDevice, mPendingIntent);
+            return true;
+        }else{
+            index++;
+            if(index <= devices.size()-1)
+                return requestPermission(context);
+            else
+                return false;
+        }
    }

    private void initReceiver(Context context){
@ -95,12 +113,16 @@ public class SerialPortBuilder {
        context.registerReceiver(usbReceiver, filter);
    }

-    private void createAllPorts(UsbDevice usbDevice){
-        int interfaceCount = usbDevice.getInterfaceCount();
+    private void createAllPorts(UsbDeviceStatus usbDeviceStatus){
+        int interfaceCount = usbDeviceStatus.usbDevice.getInterfaceCount();
        for(int i=0;i<=interfaceCount-1;i++) {
-            //TODO: Maybe opening the same device more than once causes troubles!!!
-            UsbSerialDevice usbSerialDevice = UsbSerialDevice.createUsbSerialDevice(usbDevice,
-                    usbManager.openDevice(usbDevice),
+            if(usbDeviceStatus.usbDeviceConnection == null) {
+                usbDeviceStatus.usbDeviceConnection = usbManager.openDevice(usbDeviceStatus.usbDevice);
+            }
+
+            UsbSerialDevice usbSerialDevice = UsbSerialDevice.createUsbSerialDevice(
+                    usbDeviceStatus.usbDevice,
+                    usbDeviceStatus.usbDeviceConnection,
                    i);

            serialDevices.add(usbSerialDevice);
@ -113,6 +135,7 @@ public class SerialPortBuilder {
            if (intent.getAction().equals(ACTION_USB_PERMISSION)) {
                boolean granted = intent.getExtras().getBoolean(UsbManager.EXTRA_PERMISSION_GRANTED);
                if (granted) {
+                    devices.get(index).open = true;
                    createAllPorts(devices.get(index));
                    index++;
                    if(index < devices.size()){
@ -167,4 +190,22 @@ public class SerialPortBuilder {
            serialPortCallback.onSerialPortsDetected(serialDevices, true);
        }
    }
+
+    private class UsbDeviceStatus {
+        public UsbDevice usbDevice;
+        public UsbDeviceConnection usbDeviceConnection;
+        public boolean open;
+
+        public UsbDeviceStatus(UsbDevice usbDevice) {
+            this.usbDevice = usbDevice;
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            UsbDevice objDevice = (UsbDevice) obj;
+            return (objDevice.getVendorId() ==  usbDevice.getVendorId())
+                    && (objDevice.getProductId() == usbDevice.getProductId());
+
+        }
+    }
 }