I am building 2 NFC enabled apps, one is supposed to send a message and the other to receive it.
Sending app Android Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.joyride.nfc_merchant">
<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/Theme.NFC_Merchant">
<activity
android:name=".MainActivity"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
Sending app Main Activity
package com.joyride.nfc_merchant;
import androidx.appcompat.app.AppCompatActivity;
import android.nfc.NdefMessage;
import android.nfc.NdefRecord;
import android.nfc.NfcAdapter;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
public class MainActivity extends AppCompatActivity {
String message;
NdefRecord ndefRecord;
NdefMessage ndefMessage;
NfcAdapter nfcAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
nfcAdapter = NfcAdapter.getDefaultAdapter(this);
}
public void sendMessage(View view) {
message = ((EditText) findViewById(R.id.text_message)).getText().toString();
ndefRecord = NdefRecord.createTextRecord(null, message);
ndefMessage = new NdefMessage(ndefRecord);
nfcAdapter.setNdefPushMessage(ndefMessage, this);
}
}
Receiving app android Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.joyride.nfc_customer">
<uses-permission android:name="android.permission.NFC" />
<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/Theme.NFC_Customer">
<activity
android:name=".MainActivity"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
Receiving app Main Activity
package com.joyride.nfc_customer;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.nfc.NdefMessage;
import android.nfc.NfcAdapter;
import android.os.Bundle;
import android.os.Parcelable;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
#Override
protected void onNewIntent(Intent intent) {
super.onNewIntent(intent);
TextView messageView = (TextView)findViewById(R.id.messageView);
if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(intent.getAction())) {
Parcelable[] rawMessages =
intent.getParcelableArrayExtra(NfcAdapter.EXTRA_NDEF_MESSAGES);
if (rawMessages != null) {
NdefMessage[] messages = new NdefMessage[rawMessages.length];
for (int i = 0; i < rawMessages.length; i++) {
messageView.setText(((NdefMessage) rawMessages[i]).toString());
}
}
}
}
}
I've installed each app on another phone. Off course the receiving app is not registering the message. Am I missing something here? How do I go about debugging this?
Related
I know that when I define a Broadcast receiver from manifest in bellow of intent filter I can define category that it's optional.
<receiver android:name=".PushMessageReceiver" >
<intent-filter>
<!-- Receives the actual messages. -->
<category android:name="com.test.myAppname" />
<action android:name="com.test.client.MSGRECEIVE" />
</intent-filter>
</receiver>
I googled but cant get it what is the exact point of adding category or how I can use it. I appreciate to give me some examples.
MainActivity.java
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
/**
* send
*
*/
public class MainActivity extends Activity {
private static final String MY_ACTION = "com.chaowen.action.MY_ACTION";
private Button btn;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
btn = (Button)findViewById(R.id.Button01);
btn.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Intent intent= new Intent();
intent.setAction(MY_ACTION);
//Intent message
intent.putExtra("msg", "ha ha");
//send
sendBroadcast(intent);
}
});
}
}
MyReceiver.java
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;
/**
* receive
*
*/
public class MyReceive extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
//get Intent message
String msg = intent.getStringExtra("msg");
Toast.makeText(context, msg, Toast.LENGTH_LONG).show();
}
}
main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<Button
android:text="send..."
android:id="#+id/Button01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
</LinearLayout>
AndroidManifest.xml
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.chaowen"
android:versionCode="1"
android:versionName="1.0">
<uses-sdk android:minSdkVersion="4" />
<application android:icon="#drawable/icon" android:label="#string/app_name">
<activity android:name=".MainActivity"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<receiver
android:name="MyReceive"
>
<intent-filter>
<action
android:name="com.chaowen.action.MY_ACTION" />
</intent-filter>
</receiver>
</application>
This is an app which toasts a received message and gives it a reply
when i tested with the emulator it is working fine but not on device
-----this is the MainActivity.java---------
package com.example.yj.example;
import android.app.Activity;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.Menu;
import android.view.MenuItem;
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
}
-------This is SmsReceiver.java-----------
package com.example.yj.example;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.telephony.SmsManager;
import android.telephony.SmsMessage;
import android.widget.Toast;
public class SmsReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
Bundle bundle=intent.getExtras();
if(bundle != null){
Object[] pdus= (Object[]) bundle.get("pdus");
String senderNumber=null;
for(int i=0; i<pdus.length; i++){
SmsMessage sms=SmsMessage.createFromPdu((byte[]) pdus[i]);
senderNumber = sms.getDisplayOriginatingAddress();
String message= sms.getDisplayMessageBody();
Toast.makeText(context, "From:" + senderNumber + " Message:" + message, Toast.LENGTH_LONG).show();
}
SmsManager smsManager=SmsManager.getDefault();
smsManager.sendTextMessage(senderNumber,null,"u r lucky!!!!! its finally working",null,null);
}
}
}
---------this is AndroidManifest.xml -----------------
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.yj.example" >
<uses-permission android:name="android.permission.RECEIVE_SMS"/>
<uses-permission android:name="android.permission.READ_SMS"/>
<uses-permission android:name="android.permission.SEND_SMS"/>
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<receiver android:name=".SmsReceiver">
<intent-filter>
<action android:name="android.provider.Telephony.SMS_RECEIVED"/>
</intent-filter>
</receiver>
</application>
</manifest>
i'm a beginner in Android
and i'm trying different programs but this error still show up
':app:processDebugManifest' Manifest merger failed with multiple errors
how i can fix it
this is my code
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="com.example.nhn.test">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme"
tools:replace="android:icon,android:theme"
>
<activity android:name=".MainActivity" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="Main2Activity"
android:label="#string/title_activity_main2"
android:theme="#style/AppTheme.NoActionBar" >
</activity>
<activity android:name=".Main2Activity" >
</activity>
</application>
<android:replace>"android:icon"</android:replace>
</manifest>
this is the first layout
package com.example.nhn.test;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
public class MainActivity extends AppCompatActivity {
public void BtnNex(View view){
Intent int1= new Intent(this,Main2Activity.class);
startActivity(int1);
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
}
this is the second had one button
package com.example.nhn.test;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
public class Main2Activity extends AppCompatActivity {
public void BtnPrev(View view){
Intent int2= new Intent(this,MainActivity.class);
startActivity(int2);
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
}
}
I have created 2 activities.When i call second activity from first via intent then onCreate method of second activity does not called.Although first activity's onCreate method is called normally as it should be.
Below is the code for first activity.
package com.webesperto.webespertofirstapp;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
public class MainActivity extends Activity implements OnClickListener {
int counter;
Button add, sub;
TextView tView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
counter = 0;
add = (Button) findViewById(R.id.bAdd);
sub = (Button) findViewById(R.id.bSub);
tView = (TextView) findViewById(R.id.textView1);
// Intent in = new Intent(AC);
add.setOnClickListener(this);
sub.setOnClickListener(this);
}
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
case R.id.bAdd:
tView.setText(++counter + "");
try {
Intent nextIntentView = new Intent(MainActivity.this, ShowValueActivity.class);
nextIntentView.putExtra("key", "counter");
startActivity(nextIntentView);
}
catch (Exception e) {
e.printStackTrace();
}
break;
case R.id.bSub:
tView.setText(--counter + "");
break;
default:
break;
}
}
}
Code for second activity.
package com.webesperto.webespertofirstapp;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;
public class ShowValue extends Activity {
TextView tv_showValue1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.show_value);
tv_showValue1 = (TextView) findViewById(R.id.tv_showValue);
Intent gotIntent = (Intent) this.getIntent();
Bundle gotBundle = gotIntent.getExtras();
tv_showValue1.setText(gotBundle.getString("key"));
}
}
Manifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.webesperto.webespertofirstapp"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.webesperto.webespertofirstapp.MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".ShowValueActivity"
android:label="#string/title_activity_show_value" >
</activity>
</application>
</manifest>
you have
<activity
android:name=".ShowValueActivity"
android:label="#string/title_activity_show_value" >
</activity>
instead of
<activity
android:name=".ShowValue"
android:label="#string/title_activity_show_value" >
</activity>
Since your code reads
public class ShowValue extends Activity {
Though, why doesnt your application crash saying NoActivityFoundException ??
please have a look on manifest
change
<activity
android:name=".ShowValueActivity"
android:label="#string/title_activity_show_value" >
</activity>
to
<activity
android:name=".ShowValue"
android:label="#string/title_activity_show_value" >
</activity>
yours manifest should be like this
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.webesperto.webespertofirstapp"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.webesperto.webespertofirstapp.MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".ShowValue"
android:label="#string/title_activity_show_value" >
</activity>
</application>
</manifest>
Change your Second Activity name in class file like this:
package com.webesperto.webespertofirstapp;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;
public class ShowValueActivity extends Activity {
TextView tv_showValue1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.show_value);
tv_showValue1 = (TextView) findViewById(R.id.tv_showValue);
Intent gotIntent = (Intent) this.getIntent();
Bundle gotBundle = gotIntent.getExtras();
tv_showValue1.setText(gotBundle.getString("key"));
}
}
It will work:)
I try to write app which can start when usb connect
I learn from Starting my android application automatically after connecting the USB cable.
my code is
package com.example.formatsdcard;
import java.io.File;
import android.os.Bundle;
import android.os.Environment;
import android.app.Activity;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
public class MainActivity extends Activity {
public class OnPowerReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
Intent i = new Intent(context, MainActivity.class);
i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(i);
}
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button mButton01 = (Button)findViewById(R.id.button1);
mButton01.setOnClickListener(new Button.OnClickListener()
{
public void onClick(View v)
{
wipeMemoryCard();
}
});
MY Manifest is
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.formatsdcard"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="7"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.intent.action.ACTION_POWER_CONNECTED"/>
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.example.formatsdcard.MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<receiver android:name=".OnPowerReceiver">
<intent-filter>
<action android:name="android.intent.action.ACTION_POWER_CONNECTED" />
</intent-filter>
</receiver>
</application>
my app can run after I click it but it will show there're some problem try again later when I connect my usb cable.
How should I change my code to let it work normally.
You should probably try
<receiver android:name="MainActivity$OnPowerReceiver">
<intent-filter>
<action android:name="android.intent.action.ACTION_POWER_CONNECTED" />
</intent-filter>
</receiver>
Or try putting OnPowerReceiver as a public class in your package com.example.formatsdcard
Create a own class for your onPowerReceiver. Don't put it in your MainActivity.