Version 5

Added a call screening service.

build.gradle

@@ -42,7 +42,7 @@ android {
 	defaultConfig {
 		minSdk 28
 		targetSdk compileSdk
-		versionCode 4
+		versionCode 5
 		versionName "$versionCode"
 	}
 

src/main/AndroidManifest.xml

@@ -25,6 +25,16 @@
 				<action android:name="android.intent.action.PHONE_STATE" />
 			</intent-filter>
 		</receiver>
+
+		<service
+			android:name=".CallService"
+			android:exported="true"
+			android:permission="android.permission.BIND_SCREENING_SERVICE">
+
+			<intent-filter>
+				<action android:name="android.telecom.CallScreeningService" />
+			</intent-filter>
+		</service>
 	</application>
 
 	<!-- receive phone state broadcasts -->

src/main/java/ilchev/stefan/callblocker/CallReceiver.java

@@ -29,6 +29,7 @@ private static String getIncomingNumber(Intent intent) {
 	private static boolean endCall(Context context) {
 		if (context.checkSelfPermission(Manifest.permission.ANSWER_PHONE_CALLS) != PackageManager.PERMISSION_GRANTED) {
 			Toast.makeText(context, Manifest.permission.ANSWER_PHONE_CALLS, Toast.LENGTH_LONG).show();
+			return false;
 		}
 		var telecomManager = context.getSystemService(TelecomManager.class);
 		return telecomManager != null && telecomManager.endCall();

src/main/java/ilchev/stefan/callblocker/CallService.java

@@ -0,0 +1,37 @@
+package ilchev.stefan.callblocker;
+
+import android.os.Build;
+import android.telecom.Call;
+import android.telecom.CallScreeningService;
+import android.util.Log;
+
+public class CallService extends CallScreeningService {
+
+	private static final String TAG = "CallService";
+
+	private static void endCall(CallResponse.Builder builder) {
+		builder.setDisallowCall(true)
+				.setRejectCall(true)
+				.setSkipNotification(true);
+	}
+
+	@Override
+	public void onScreenCall(Call.Details callDetails) {
+		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q &&
+				callDetails.getCallDirection() != Call.Details.DIRECTION_INCOMING) {
+			return;
+		}
+		var builder = new CallResponse.Builder();
+		try (AutoCloseable ignored = () -> respondToCall(callDetails, builder.build())) {
+			var phoneNumber = callDetails.getHandle().getSchemeSpecificPart();
+			var sharedPreferences = getSharedPreferences(BuildConfig.APPLICATION_ID, MODE_PRIVATE);
+			var callBlocker = new CallBlocker(sharedPreferences);
+			if (callBlocker.isBlocked(phoneNumber)) {
+				endCall(builder);
+				CallReceiver.notifyBlockedCall(this, phoneNumber);
+			}
+		} catch (Throwable t) {
+			Log.w(TAG, t);
+		}
+	}
+}

src/main/java/ilchev/stefan/callblocker/MainActivity.java

@@ -3,6 +3,8 @@
 import android.Manifest;
 import android.annotation.SuppressLint;
 import android.app.Activity;
+import android.app.role.RoleManager;
+import android.content.Intent;
 import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager;
 import android.os.Build;
@@ -11,14 +13,15 @@
 import android.text.TextWatcher;
 import android.util.Log;
 import android.view.View;
+import android.widget.CompoundButton;
 import android.widget.EditText;
 import android.widget.RadioGroup;
 import android.widget.TextView;
 
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashSet;
-import java.util.function.Function;
+import java.util.function.Consumer;
 
 public class MainActivity extends Activity {
 
@@ -40,6 +43,31 @@ private static Boolean toBoolean(int value) {
 				: null;
 	}
 
+	private final TextWatcher regexListener = new TextWatcher() {
+
+		@Override
+		public void beforeTextChanged(CharSequence s, int start, int count, int after) {
+		}
+
+		@Override
+		public void onTextChanged(CharSequence s, int start, int before, int count) {
+		}
+
+		@Override
+		public void afterTextChanged(Editable s) {
+			var regex = s + "";
+			updateContent(R.id.regex, callBlocker -> callBlocker.setRegex(regex));
+		}
+	};
+
+	private final RadioGroup.OnCheckedChangeListener blockListener = (group, checkedId) -> {
+		var isMatches = toBoolean(checkedId);
+		updateContent(R.id.block, callBlocker -> callBlocker.setMatches(isMatches));
+	};
+
+	private final CompoundButton.OnCheckedChangeListener screenerListener = (buttonView, isChecked) ->
+			updateScreener(buttonView);
+
 	@SuppressWarnings({"deprecation", "RedundantSuppression"})
 	private PackageInfo getPackageInfo(int flags) throws PackageManager.NameNotFoundException {
 		var packageManager = getPackageManager();
@@ -49,25 +77,34 @@ private PackageInfo getPackageInfo(int flags) throws PackageManager.NameNotFound
 				: packageManager.getPackageInfo(packageName, PackageManager.PackageInfoFlags.of(flags));
 	}
 
-	private void updateContent(int sourceId, Function<CallBlocker, Boolean> function) {
+	private void tryStartActivityForResult(Intent intent, int requestCode, Bundle options) {
+		try {
+			startActivityForResult(intent, requestCode, options);
+		} catch (Throwable t) {
+			Log.w(TAG, t);
+		}
+	}
+
+	private void updateContent(int sourceId, Consumer<CallBlocker> consumer) {
 		var sharedPreferences = getSharedPreferences(BuildConfig.APPLICATION_ID, MODE_PRIVATE);
 		String error = null;
 		try {
 			var callBlocker = new CallBlocker(sharedPreferences);
-			var isLoop = function != null ? function.apply(callBlocker) : null;
-			if (isLoop != null) {
-				if (isLoop) {
-					return;
-				}
+			if (consumer != null) {
+				consumer.accept(callBlocker);
 				callBlocker.put(sharedPreferences.edit()).apply();
 			}
 			EditText regexView = sourceId != R.id.regex ? findViewById(R.id.regex) : null;
 			if (regexView != null) {
+				regexView.removeTextChangedListener(regexListener);
 				regexView.setText(callBlocker.getRegex());
+				regexView.addTextChangedListener(regexListener);
 			}
 			RadioGroup blockView = sourceId != R.id.block ? findViewById(R.id.block) : null;
 			if (blockView != null) {
+				blockView.setOnCheckedChangeListener(null);
 				blockView.check(toBlockId(callBlocker.isMatches()));
+				blockView.setOnCheckedChangeListener(blockListener);
 			}
 		} catch (Throwable t) {
 			error = t.getLocalizedMessage();
@@ -79,45 +116,32 @@ private void updateContent(int sourceId, Function<CallBlocker, Boolean> function
 		}
 	}
 
-	private final TextWatcher regexListener = new TextWatcher() {
-
-		@Override
-		public void beforeTextChanged(CharSequence s, int start, int count, int after) {
-		}
+	private void updateScreener(CompoundButton screener, int visibility, boolean isChecked) {
+		screener.setVisibility(visibility);
+		screener.setOnCheckedChangeListener(null);
+		screener.setChecked(isChecked);
+		screener.setOnCheckedChangeListener(screenerListener);
+	}
 
-		@Override
-		public void onTextChanged(CharSequence s, int start, int before, int count) {
+	private void updateScreener(CompoundButton buttonView) {
+		CompoundButton screener = buttonView != null ? buttonView : findViewById(R.id.screener);
+		if (screener == null) {
+			return;
 		}
-
-		@Override
-		public void afterTextChanged(Editable s) {
-			var regex = s + "";
-			updateContent(R.id.regex, callBlocker -> {
-				var result = regex.equals(callBlocker.getRegex());
-				callBlocker.setRegex(regex);
-				return result;
-			});
+		if (Build.VERSION.SDK_INT < Build.VERSION_CODES.Q) {
+			updateScreener(screener, View.GONE, false);
+			return;
 		}
-	};
-
-	private final RadioGroup.OnCheckedChangeListener blockListener = (group, checkedId) -> {
-		var isMatches = toBoolean(checkedId);
-		updateContent(R.id.block, callBlocker -> {
-			var result = isMatches == callBlocker.isMatches();
-			callBlocker.setMatches(isMatches);
-			return result;
-		});
-	};
-
-	private void initContent() {
-		EditText regexView = findViewById(R.id.regex);
-		if (regexView != null) {
-			regexView.removeTextChangedListener(regexListener);
-			regexView.addTextChangedListener(regexListener);
+		var roleManager = getSystemService(RoleManager.class);
+		if (roleManager == null || !roleManager.isRoleAvailable(RoleManager.ROLE_CALL_SCREENING)) {
+			updateScreener(screener, View.GONE, false);
+			return;
 		}
-		RadioGroup blockView = findViewById(R.id.block);
-		if (blockView != null) {
-			blockView.setOnCheckedChangeListener(blockListener);
+		var isRoleHeld = roleManager.isRoleHeld(RoleManager.ROLE_CALL_SCREENING);
+		updateScreener(screener, View.VISIBLE, isRoleHeld);
+		if (buttonView != null && !isRoleHeld) {
+			var intent = roleManager.createRequestRoleIntent(RoleManager.ROLE_CALL_SCREENING);
+			tryStartActivityForResult(intent, 0, null);
 		}
 	}
 
@@ -144,8 +168,13 @@ protected void onCreate(Bundle savedInstanceState) {
 		super.onCreate(savedInstanceState);
 		setContentView(R.layout.activity_main);
 		updateContent(View.NO_ID, null);
-		initContent();
 		requestRequestedPermissions();
 		CallReceiver.notifyBlockedCall(this, null);
 	}
+
+	@Override
+	protected void onResume() {
+		super.onResume();
+		updateScreener(null);
+	}
 }

src/main/res/layout/activity_main.xml

@@ -9,6 +9,13 @@
 		android:layout_height="wrap_content"
 		android:paddingHorizontal="14dp">
 
+		<CheckBox
+			android:id="@+id/screener"
+			android:layout_width="match_parent"
+			android:layout_height="wrap_content"
+			android:paddingVertical="14dp"
+			android:text="@string/call_screener" />
+
 		<EditText
 			android:id="@+id/regex"
 			android:layout_width="match_parent"

src/main/res/values/strings.xml

@@ -1,6 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
 	<string name="app_name" translatable="false">Call Blocker</string>
+	<string name="call_screener" translatable="false">Call Screener</string>
 	<string name="regex" translatable="false">Regex</string>
 	<string name="block_none" translatable="false">Block None</string>
 	<string name="block_matches" translatable="false">Block Matches</string>