since API 23 it is possible, see Replacing default Phone app on Android 6 and 7 with InCallService arekolek.
Kotlin version: Simple Phone
Java version: Simple Phone Dialer
EDIT
As recommended, Below is the simplest java version.
Below is shown the Manifest with the intent-filter needed.
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.aliton.customphonecall">
<uses-permission android:name="android.permission.CALL_PHONE" />
<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>
<activity
android:name=".DialerActivity" >
<intent-filter>
<!-- Handle links from other applications -->
<action android:name="android.intent.action.VIEW" />
<action android:name="android.intent.action.DIAL" />
<!-- Populate the system chooser -->
<category android:name="android.intent.category.DEFAULT" />
<!-- Handle links in browsers -->
<category android:name="android.intent.category.BROWSABLE" />
<data android:scheme="tel" />
</intent-filter>
<intent-filter>
<action android:name="android.intent.action.DIAL" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<service
android:name=".CallService"
android:permission="android.permission.BIND_INCALL_SERVICE">
<meta-data
android:name="android.telecom.IN_CALL_SERVICE_UI"
android:value="true" />
<intent-filter>
<action android:name="android.telecom.InCallService" />
</intent-filter>
</service>
<activity android:name=".CallActivity"></activity>
</application>
</manifest>
The MainActivity just have a Button with an Intent redirecting to the DialerActivity.
Below is the DialerActivity. In this Activity, you will set your app as default in order to make call with your UI.
public class DialerActivity extends AppCompatActivity {
private static final int REQUEST_CALL_PHONE = 10;
EditText phoneNumber;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_dialer);
phoneNumber = (EditText) findViewById(R.id.etNumber);
Button bCall = (Button) findViewById(R.id.btnCall);
offerReplacingDefaultDialer();
bCall.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
makeCall();
}
});
}
private void makeCall() {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.CALL_PHONE) == PackageManager.PERMISSION_GRANTED) {
Uri uri = Uri.parse("tel:"+phoneNumber.getText().toString().trim());
Intent Call = new Intent(Intent.ACTION_CALL, uri);
//Toast.makeText(this, "Entered makeCall()", Toast.LENGTH_SHORT).show();
Log.i("debinf Dialer", "Entered makeCall()");
startActivity(Call);
} else {
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CALL_PHONE}, REQUEST_CALL_PHONE);
}
}
private void offerReplacingDefaultDialer() {
if (getSystemService(TelecomManager.class).getDefaultDialerPackage() != getPackageName()) {
Intent ChangeDialer = new Intent(TelecomManager.ACTION_CHANGE_DEFAULT_DIALER);
ChangeDialer.putExtra(TelecomManager.EXTRA_CHANGE_DEFAULT_DIALER_PACKAGE_NAME, getPackageName());
startActivity(ChangeDialer);
}
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
if (requestCode == REQUEST_CALL_PHONE) {
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
makeCall();
} else {
Toast.makeText(this, "calling permission denied", Toast.LENGTH_LONG).show();
}
//return;
}
}
}
Here is how InCallService is implemented to manage the calls.
public class CallService extends InCallService {
OngoingCallObject ongoingCallObject;
@Override
public void onCallAdded(Call call) {
super.onCallAdded(call);
new OngoingCallObject().setCall(call);
//Intent CallAct = new Intent(this, CallActivity.class);
//startActivity(CallAct);
CallActivity.start(this, call);
}
@Override
public void onCallRemoved(Call call) {
super.onCallRemoved(call);
new OngoingCallObject().setCall(null);
}
}
Here is how the Object is implemented.
public class OngoingCallObject {
private static Call call;
private Object callback = new Callback() {
@Override
public void onStateChanged(Call call, int state) {
super.onStateChanged(call, state);
Log.i("debinf OngoingObj", "state is "+state);
}
};
public void setCall(Call call) {
if (this.call != null) {
this.call.unregisterCallback((Call.Callback)callback);
}
if (call != null) {
call.registerCallback((Call.Callback)callback);
Log.i("debinf OngoingObj", "call.getState() is "+call.getState());
}
this.call = call;
}
public void answer() {
//assert this.call != null;
if (this.call != null) {
this.call.answer(VideoProfile.STATE_AUDIO_ONLY);
}
}
public void hangup() {
//assert this.call != null;
if (this.call != null) {
this.call.disconnect();
}
}
}
And finally, the CallActivity where you launch your UI.
public class CallActivity extends AppCompatActivity {
TextView callInfo;
Button answer, hangup;
private String number;
private OngoingCallObject ongoingCall;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_call);
ongoingCall = new OngoingCallObject();
answer = (Button) findViewById(R.id.answer);
hangup = (Button) findViewById(R.id.hangup);
callInfo = (TextView) findViewById(R.id.callInfo);
number = Objects.requireNonNull(getIntent().getData().getSchemeSpecificPart());
callInfo.setText("Calling number : "+number);
answer.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//Toast.makeText(CallActivity.this, "Answer button", Toast.LENGTH_SHORT).show();
ongoingCall.answer();
}
});
hangup.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
ongoingCall.hangup();
}
});
}
public static void start(Context context, Call call) {
Intent intent = new Intent(context, CallActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.setData(call.getDetails().getHandle());
context.startActivity(intent);
}
}
Here is the xml for DialerActivity: activity_dialer.xml
<RelativeLayout 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=".DialerActivity">
<EditText
android:id="@+id/etNumber"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="Tel number"/>
<Button
android:id="@+id/btnCall"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:text="CallActivity"
android:layout_below="@+id/etNumber" />
</RelativeLayout>
Here is the xml for CallActivity: activity_call.xml
<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=".CallActivity">
<TextView
android:id="@+id/callInfo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.3"
tools:text="Hello World!" />
<Button
android:id="@+id/answer"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Answer"
app:layout_constraintBaseline_toBaselineOf="@+id/hangup"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@+id/hangup" />
<Button
android:id="@+id/hangup"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hang up"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="@+id/answer"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/callInfo" />
</android.support.constraint.ConstraintLayout>
I hope it helps!
