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Two apps communicating using Intent, passing data

I'm trying to solve an issue passing data between different apps using Intent.
The scenario is like this:
Main (App 1): User clicks Register
Main App launches Register activity (form) in Register (App 2)
User enters first name, last name etc, clicks Send Back
Register app returning values to Main app
Main app displays user's data
Note that Register activity is not the main activity in Register activity.
I would like to solve this without an additional class and without Broadcasting.
My code for Main App, user clicks Register method:
/* User clicks Register */
public void clickRegister(View view) {
Intent intent = new Intent(Intent.ACTION_SEND);
// Verify it resolves
PackageManager packageManager = getPackageManager();
List<ResolveInfo> activities = packageManager.queryIntentActivities(intent, 0);
boolean isIntentSafe = activities.size() > 0;
// Start an activity if it's safe
if (isIntentSafe) {
startActivity(intent);
}
}
Manifest file for Register activity in Register App:
<activity android:name="com.example.register.Register">
<intent-filter>
<action android:name="android.intent.action.SEND"/>
<category android:name="android.intent.category.DEFAULT"/>
<data android:mimeType="text/plain"/>
</intent-filter>
</activity>
Now, this is the code in Register activity, of click Send Back method:
/* User clicks Send Back in register activity */
public void clickSendBack(View view) {
// Create an Intent for Register class
// Intent myIntent = new Intent(this, MainActivity.class);
Intent myIntent = new Intent(Intent.ACTION_SEND);
final EditText firstNameInput = (EditText) findViewById(R.id.firstNameEditText);
final EditText secondNameInput = (EditText) findViewById(R.id.secondNameEditText);
String firstName = firstNameInput.getText().toString();
String secondName = secondNameInput.getText().toString();
myIntent.setAction(Intent.ACTION_SEND);
myIntent.putExtra("firstName",firstName);
myIntent.putExtra("secondName",secondName);
myIntent.setType("text/plain");
// Starts activity
startActivity(myIntent);
finish();
}
And here I'm stuck.
Would love to hear any clarification for this topic, and a example for a solution would also be great.
Thanks!

In the first app, add an intent-filter to receive data back from the second app, which is your Register application.
Now, do the same with your Register application, we need to do this so that we can invoke it from our first app.
The intent-filter is there to make sure that we can send data back. According to https://developer.android.com/guide/components/intents-filters:
To advertise which implicit intents your app can receive, declare one or more intent filters for each of your app components with an element in your manifest file.
From the first app, create an Intent that will bring you to the second app. If you don't want to open up the Android share sheet then I suggest you use a PackageManager that gets all the activities that can receive your data and then find in the list your second app and open it with setComponent() with your intent. (Check my code below)
On to our second app, do the same as you did in the first app but now you can add your extras or data like first name and second name.
Back to our first app, write code that will receive the incoming intent from our second app and there, done!
Refer to:
https://developer.android.com/training/sharing
for more information about sending/receiving data with intents.
Here's a sample code:
First Application's Main Activity
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Receive your data here from your Register app
Intent receivedIntent = getIntent();
String action = receivedIntent.getAction();
String type = receivedIntent.getType();
if (Intent.ACTION_SEND.equals(action) && type != null) {
if ("text/plain".equals(type)) {
handleReceivedData(receivedIntent);
}
}
}
private void handleReceivedData(Intent intent) {
String firstName = intent.getStringExtra("first_name");
String secondName = intent.getStringExtra("second_name");
if (firstName == null || secondName == null) {
Toast.makeText(this, "Cannot received data!", Toast.LENGTH_SHORT).show();
return;
}
// Do here what you want with firstName and secondName
// ...
Toast.makeText(this, "First name: " + firstName +
" Second name: " + secondName, Toast.LENGTH_SHORT).show();
}
public void open(View view) {
Intent sendIntent = new Intent();
sendIntent.setAction(Intent.ACTION_SEND);
sendIntent.putExtra(Intent.EXTRA_TEXT,
"Here you can put a message for your 'register' application");
sendIntent.setType("text/plain");
PackageManager packageManager = getPackageManager();
List<ResolveInfo> activities = packageManager.queryIntentActivities(sendIntent,
PackageManager.MATCH_DEFAULT_ONLY);
////////////////// Get the other application package name //////////////////
// This is so the user cannot choose other apps to send your data
// In order words, this will send the data back to the other
// application without opening the Android Share sheet
ActivityInfo activityInfo = null;
for (ResolveInfo activity: activities) {
// Specify here the package name of your register application
if (activity.activityInfo.packageName.equals("com.example.registerapp")) {
activityInfo = activity.activityInfo;
break;
}
}
// If the other application is not found then activityInfo will be null
// So make sure you add the correct intent-filter there!
if (activityInfo != null) {
// This will open up your register application
ComponentName name = new ComponentName(activityInfo.applicationInfo.packageName,
activityInfo.name);
sendIntent.setComponent(name);
startActivity(sendIntent);
}
else {
Toast.makeText(this,
"Receiver app doesn't exist or not installed on this device!",
Toast.LENGTH_SHORT).show();
}
}
First Application's Manifest
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<intent-filter>
<action android:name="android.intent.action.SEND" />
<category android:name="android.intent.category.DEFAULT" />
<data android:mimeType="text/plain" />
</intent-filter>
</activity>
Second Application's Receiver Activity (In this case, your Register app)
Note: as you want, this is NOT the main activity
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_receiver);
// This is NOT the main activity!
}
public void send(View view) {
// I just want to note that I am calling the receiving application: "other application"
EditText firstNameEditText = findViewById(R.id.firstNameEditText);
EditText secondNameEditText = findViewById(R.id.secondNameEditText);
String firstName = firstNameEditText.getText().toString().trim();
String secondName = secondNameEditText.getText().toString().trim();
// Check if any of the inputs are empty
if (firstName.isEmpty() || secondName.isEmpty()) {
Toast.makeText(this, "Text boxes cannot be empty!", Toast.LENGTH_SHORT).show();
return;
}
// Send data back to the other application
Intent sendBackIntent = new Intent();
sendBackIntent.setAction(Intent.ACTION_SEND);
sendBackIntent.putExtra("first_name", firstName);
sendBackIntent.putExtra("second_name", secondName);
sendBackIntent.setType("text/plain");
// Get all the available applications that can receive your data
// (in this case, first name and second name)
PackageManager packageManager = getPackageManager();
List<ResolveInfo> activities = packageManager.queryIntentActivities(sendBackIntent,
PackageManager.MATCH_DEFAULT_ONLY);
////////////////// Get the other application package name //////////////////
ActivityInfo activityInfo = null;
for (ResolveInfo activity: activities) {
// Specify here the package name of the other application
if (activity.activityInfo.packageName.equals("com.example.mainapp")) {
activityInfo = activity.activityInfo;
break;
}
}
if (activityInfo != null) {
// Same as before, this will open up the other application
ComponentName name = new ComponentName(activityInfo.applicationInfo.packageName,
activityInfo.name);
sendBackIntent.setComponent(name);
startActivity(sendBackIntent);
}
else {
Toast.makeText(this,
"Receiver app doesn't exist or not installed on this device!",
Toast.LENGTH_SHORT).show();
}
}
Second Application's Manifest
<activity android:name=".ReceiverActivity">
<intent-filter>
<action android:name="android.intent.action.SEND" />
<category android:name="android.intent.category.DEFAULT" />
<data android:mimeType="text/plain" />
</intent-filter>
</activity>
Happy coding!
Edit: I added explanation to my answer.

Your RegisterActivity should look like so
RegisterActivity is parsing the user data to the MainActivity
/* User clicks Send Back in register activity */
public void clickSendBack(View view) {
// Create an Intent for Register class
final EditText firstNameInput =
findViewById(R.id.firstNameEditText);
final EditText secondNameInput =
findViewById(R.id.secondNameEditText);
String firstName = firstNameInput.getText().toString();
String secondName = secondNameInput.getText().toString();
Intent i = new Intent(RegisterActiivty.this, MainActivity.class);
i.putExtra("firstName", firstName);
i.putExtra("secondName", secondName);
startActivity(i);
}
#################################################################
Your MainActivity should look like so.
The MainActivity is responsible for receiving the data
This line of codes should be called in your onCreate method of MainActivity
String firstName = getIntent().getStringExtra("firstName");
String secondName = getIntent().getStringExtra("firstName")
// if you have a TextView on MainActivity you could display the data you have
//gotten from the RegisterActivity like so
Textview firstName = findViewById(R.id.firstName);
firstName.setText(firstName);
Textview secondName = findViewById(R.id.secondName);
secondName.setText(secondName);
/* User clicks Register */
public void clickRegister(View view) {
startActivity(Intent(this, RegisterActivity.class))
}
##########################################################
Your manifest should look like this
<activity android:name="com.example.register.Register"/>
I am trying to wrap my head around what you meant by Main App and Register.
It sound as though they are two different apps or probably two different
project modules. But if what you are trying to say is MainActivity and
RegisterActivity then the above solution should be able to fix your problem.
What you did wrong:
That intent you were trying to parse in the manifest was not needed. If I understood properly what you are trying to achieve. The same goes for the MainActivity and RegisterActivity. You were using Implicit Intent instead of explicit Intent. And when calling findViewById this extra (EditText) was not needed because it is redundant. For more on the intent you can check this
However, this guide should be useful to anyone seeking to parse data from one activity to another.

Speed up the startup of BroadcastReceiver at reboot

I've an app where the user can call custom lock screen to lock his/her mobile, that is an activity called LockScreen.class.
One this screen is loaded, i.e. the deviced is locked, a SharedPreferences called IsLocked is assigned to be true.
once the user do what he need with tthe lock screen this islocked became false, and the mobile is back to normal.
Every hing is working fine as expected.
The problem is, if for some reason the mobile had been rebooted while the lock screen is active, it is not running back upon a reboot.
So, I created a BootReciever as below, this works fine BUT after having the reboot process completed, and the user can do many things before it is loaded, my question is how can I make it loaded faster? so that the mobile screen is locked again with the custom activity before giving the chance for the user to do anything with the mobile?
public class BootReciever extends BroadcastReceiver
{
SharedPreferences mPrefs;
final String IsLockedPref = "IsLocked";
#Override
public void onReceive(Context context, Intent intent) {
mPrefs = PreferenceManager.getDefaultSharedPreferences(context);
Boolean islocked = mPrefs.getBoolean(IsLockedPref, false);
Intent i;
if (islocked)
i = new Intent(context, LockScreen.class);
else
i = new Intent(context, MainActivity.class);
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(i);
}
}
part of the manifiest file is:
<receiver android:name=".BootReciever"
android:enabled="true"
android:exported="true">
<intent-filter >
<action android:name="android.intent.action.BOOT_COMPLETED"/>
<action android:name="android.intent.action.QUICKBOOT_POWERON" />
</intent-filter>
</receiver>
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
UPDATE
I tried to get use of this by granting Device Admin by adding the below, but nothing improved:
In the main Activity:
private static final int ADMIN_INTENT = 15;
private static final String description = "Some Description About Your Admin";
private DevicePolicyManager mDevicePolicyManager;
private ComponentName mComponentName;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mDevicePolicyManager = (DevicePolicyManager)getSystemService(
this.DEVICE_POLICY_SERVICE);
mComponentName = new ComponentName(this, AdminReceiver.class);
Intent intent = new Intent(DevicePolicyManager.ACTION_ADD_DEVICE_ADMIN);
intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN, mComponentName);
intent.putExtra(DevicePolicyManager.EXTRA_ADD_EXPLANATION,description);
startActivityForResult(intent, ADMIN_INTENT);
.
.
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == ADMIN_INTENT) {
if (resultCode == RESULT_OK) {
Toast.makeText(getApplicationContext(), "Registered As Admin", Toast.LENGTH_SHORT).show();
}else{
Toast.makeText(getApplicationContext(), "Failed to register as Admin", Toast.LENGTH_SHORT).show();
}
}
}
and created empty receiver to extend the DeviceAdminReceiver as:
public class AdminReceiver extends DeviceAdminReceiver {
}
and added the below to the manifiest:
<receiver
android:name="AdminReceiver"
android:permission="android.permission.BIND_DEVICE_ADMIN">
<meta-data
android:name="android.app.device_admin"
android:resource="#xml/admin"/>
<intent-filter>
<action android:name="android.app.action.DEVICE_ADMIN_ENABLED" />
</intent-filter>
</receiver>

One thing you can do from your side is to set a priority to your intent-filter. From documentation
It controls the order in which broadcast receivers are executed to receive broadcast messages. Those with higher priority values are called before those with lower values.
<intent-filter
android:priority="100">
...
</intent-filter>
The value must be an integer, such as "100". Higher numbers have a higher priority. The default value is 0. The value must be greater than -1000 and less than 1000.

How can i change incoming call screen of phone in java?

I want to change incoming call screen to my own layout. I used a sample to do this for me. but it sometimes appear(when calling) and sometimes not. I do not know how to solve this problem that my own layout appear every time.
This is my codes.
public class PhoneStateReceiver extends BroadcastReceiver {
#Override
public void onReceive(final Context context, Intent intent) {
Intent i = new Intent();
i.setClass(context, MainActivity.class);
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(i);
}
}
and this is the manifest.
<receiver android:name="com.example.changescreen.PhoneStateReceiver">
<intent-filter>
<action android:name="android.intent.action.PHONE_STATE" />
</intent-filter>
</receiver>

Try adding a delay before starting your activity.
The Problem is your activity is being overlapped by the default activity

Unable to get Broadcast

I am unable to receive broadcast intent, although I have registered it . Can you please spot the error. Thank you very much. I tried with log messages, but it never reached onReceive() of broadcast receiver class.
Here is Class from which I send Broadcast
public class ServiceDemoActivity extends Activity {
Button startButton,stopButton,pauseButton;
final String musicIntentAction="com.CompetenceProject.Musicfilter";
Intent musicIntent=new Intent();
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
startButton=(Button)findViewById(R.id.startButton);
stopButton=(Button)findViewById(R.id.Stopbutton);
pauseButton=(Button)findViewById(R.id.Pausebutton);
musicIntent.setAction(musicIntentAction);
startButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Log.w("DEBUG", "Came to StartButton");
musicIntent.putExtra("Message","start");
sendBroadcast(musicIntent);
Toast.makeText(getApplicationContext(), "starBroadcaseSent",1000).show();
}
});
stopButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Log.w("DEBUG", "Came to StopButton");
musicIntent.putExtra("Message","stop");
sendBroadcast(musicIntent);
Toast.makeText(getApplicationContext(), "stopBroadcaseSent",1000).show();
}
});
pauseButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Log.w("DEBUG", "Came to PauseButton");
musicIntent.putExtra("Message","pause");
sendBroadcast(musicIntent);
Toast.makeText(getApplicationContext(), "PauseBroadcaseSent",1000).show();
}
});
}
}
Here is Class that listens to broadcast:
public class MusicBroadcsatListener extends BroadcastReceiver{
#Override
public void onReceive(Context context, Intent intent) {
Log.w("DEBUG", "Came to BroadCast OnRecieve");
Bundle extras = intent.getExtras();
String res=extras.getString("Message");
Toast.makeText(context, "Intent Extra is "+res, 1000).show();
Log.v("BroadCase","true");
System.out.println("Broadcast came here");
if(res.equalsIgnoreCase("start"))
Toast.makeText(context, "start", 1000).show();
else if(res.equalsIgnoreCase("pause"))
Toast.makeText(context, "pause", 1000).show();
else if (res.equalsIgnoreCase("stop"))
Toast.makeText(context, "stop", 1000).show();
}
}
This is the Androidmanifest:
<activity
android:label="#string/app_name"
android:name=".ServiceDemoActivity" >
<intent-filter >
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<receiver android:name=".MusicBroadcsatListener" android:enabled="true">
<intent-filter>
<action android:name="com.CompetenceProject.Musicfilter"></action>
</intent-filter>
</receiver>
Thank you.

First thing I would do is check this typo you have in your Manifest.xml file. I can't see the name of your receiver class here, but if its name has "broadcast" in it, you spelled "broadcast" wrong -- "MusicBroadcsatListenter" -- in your manifest.xml file:
<receiver android:name=".MusicBroadcsatListener" android:enabled="true">

To test, you have to execute the broadcast receiver before you execute the activity -- on the same device -- because the receiver needs to be running. I'm not sure the best way to do this, but out of curiosity I copied and pasted your code into Eclipse into two separate projects -- one for the receiver and one for the activity. I executed the receiver project, then the activity project, and your code worked fine. If someone has a better way to test this, please post as I'd like to know too.

I found the solution by myself. I had put the receiver inside the activity tag. Thank you all for the support.

Sending data from service to activity

I am having issue when sending data from Service to Activity through Notification , I click a Notification an Activity get invoked but when i try to add some parameters through bundle i am not able to get the parameters in that called intent , I have gone through the link
How to send parameters from a notification-click to an activity?
But still no luck.
Has the same issue occurred with somebody else ?
Thanks in advance.

You have to modify the Manifest file as well.
Here is the example that works:
These variables and methods are members of Service class:
public static final String MOVEMENT_UPDATE = "com.client.gaitlink.AccelerationService.action.MOVEMENT_UPDATE";
public static final String ACCELERATION_X = "com.client.gaitlink.AccelerationService.ACCELERATION_X";
public static final String ACCELERATION_Y = "com.client.gaitlink.AccelerationService.ACCELERATION_Y";
public static final String ACCELERATION_Z = "com.client.gaitlink.AccelerationService.ACCELERATION_Z";
private void announceAccelerationChanges()//this method sends broadcast messages
{
Intent intent = new Intent(MOVEMENT_UPDATE);
intent.putExtra(ACCELERATION_X, accelerationX);
intent.putExtra(ACCELERATION_Y, accelerationY);
intent.putExtra(ACCELERATION_Z, accelerationZ);
sendBroadcast(intent);
}
And this are the methods from Main activity:
You have to register receiver in the onResume method:
#Override
public void onResume()
{
IntentFilter movementFilter;
movementFilter = new IntentFilter(AccelerationService.MOVEMENT_UPDATE);
accelerationReceiver = new AccelerationServiceReceiver();
registerReceiver(accelerationReceiver, movementFilter);
startAccelerationService();
super.onResume();
}
private void startAccelerationService()
{
startService(new Intent(this, AccelerationService.class));
}
public class AccelerationServiceReceiver extends BroadcastReceiver
{
#Override
public void onReceive(Context context, Intent intent)//this method receives broadcast messages. Be sure to modify AndroidManifest.xml file in order to enable message receiving
{
accelerationX = intent.getDoubleExtra(AccelerationService.ACCELERATION_X, 0);
accelerationY = intent.getDoubleExtra(AccelerationService.ACCELERATION_Y, 0);
accelerationZ = intent.getDoubleExtra(AccelerationService.ACCELERATION_Z, 0);
announceSession();
updateGUI();
}
}
This is the part of AndroidManifest.xml file that has to be set in order to receive broadcast messages:
<activity android:name=".GaitLink"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
<action android:name="com.client.gaitlink.CommunicationService.action.ACTIVITY_STATUS_UPDATE" />
</intent-filter>
</activity>