diff --git a/samples/android/15-puzzle/gradle/AndroidManifest.xml b/samples/android/15-puzzle/gradle/AndroidManifest.xml
index 6d1d2b3bc5..1495649220 100644
--- a/samples/android/15-puzzle/gradle/AndroidManifest.xml
+++ b/samples/android/15-puzzle/gradle/AndroidManifest.xml
@@ -8,6 +8,7 @@
         android:label="@string/app_name">
 
         <activity
+            android:exported="true"
             android:name=".Puzzle15Activity"
             android:label="@string/app_name"
             android:screenOrientation="landscape"
diff --git a/samples/android/camera-calibration/gradle/AndroidManifest.xml b/samples/android/camera-calibration/gradle/AndroidManifest.xml
index eaade4a7ba..d1640199d7 100644
--- a/samples/android/camera-calibration/gradle/AndroidManifest.xml
+++ b/samples/android/camera-calibration/gradle/AndroidManifest.xml
@@ -7,7 +7,9 @@
         android:label="@string/app_name"
         android:icon="@drawable/icon">
 
-        <activity android:name="CameraCalibrationActivity"
+        <activity
+                  android:exported="true"
+                  android:name="CameraCalibrationActivity"
                   android:label="@string/app_name"
                   android:screenOrientation="landscape"
                   android:configChanges="keyboardHidden|orientation">
diff --git a/samples/android/color-blob-detection/gradle/AndroidManifest.xml b/samples/android/color-blob-detection/gradle/AndroidManifest.xml
index 1f09a5e3ca..4fb8b58210 100644
--- a/samples/android/color-blob-detection/gradle/AndroidManifest.xml
+++ b/samples/android/color-blob-detection/gradle/AndroidManifest.xml
@@ -8,7 +8,9 @@
         android:icon="@drawable/icon"
         android:theme="@android:style/Theme.NoTitleBar.Fullscreen" >
 
-        <activity android:name="ColorBlobDetectionActivity"
+        <activity
+                  android:exported="true"
+                  android:name="ColorBlobDetectionActivity"
                   android:label="@string/app_name"
                   android:screenOrientation="landscape"
                   android:configChanges="keyboardHidden|orientation">
diff --git a/samples/android/face-detection/gradle/AndroidManifest.xml b/samples/android/face-detection/gradle/AndroidManifest.xml
index e3a46ac5a0..157b318d3b 100644
--- a/samples/android/face-detection/gradle/AndroidManifest.xml
+++ b/samples/android/face-detection/gradle/AndroidManifest.xml
@@ -7,7 +7,9 @@
         android:label="@string/app_name"
         android:icon="@drawable/icon">
 
-        <activity android:name="FdActivity"
+        <activity
+                  android:exported="true"
+                  android:name="FdActivity"
                   android:label="@string/app_name"
                   android:screenOrientation="landscape"
                   android:configChanges="keyboardHidden|orientation">
diff --git a/samples/android/image-manipulations/gradle/AndroidManifest.xml b/samples/android/image-manipulations/gradle/AndroidManifest.xml
index bc89d9615d..2aa9c09ad6 100644
--- a/samples/android/image-manipulations/gradle/AndroidManifest.xml
+++ b/samples/android/image-manipulations/gradle/AndroidManifest.xml
@@ -7,7 +7,9 @@
         android:label="@string/app_name"
         android:icon="@drawable/icon">
 
-        <activity android:name="ImageManipulationsActivity"
+        <activity
+                  android:exported="true"
+                  android:name="ImageManipulationsActivity"
                   android:label="@string/app_name"
                   android:screenOrientation="landscape"
                   android:configChanges="keyboardHidden|orientation">
diff --git a/samples/android/mobilenet-objdetect/gradle/AndroidManifest.xml b/samples/android/mobilenet-objdetect/gradle/AndroidManifest.xml
index d17e633b41..473a5db3d0 100644
--- a/samples/android/mobilenet-objdetect/gradle/AndroidManifest.xml
+++ b/samples/android/mobilenet-objdetect/gradle/AndroidManifest.xml
@@ -10,8 +10,10 @@
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
         android:theme="@style/Theme.AppCompat.NoActionBar">  <!--Full screen mode-->
-        <activity android:name=".MainActivity"
-            android:screenOrientation="landscape">  <!--Screen orientation-->
+        <activity
+                  android:exported="true"
+                  android:name=".MainActivity"
+                  android:screenOrientation="landscape">  <!--Screen orientation-->
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.LAUNCHER" />
diff --git a/samples/android/tutorial-1-camerapreview/gradle/AndroidManifest.xml b/samples/android/tutorial-1-camerapreview/gradle/AndroidManifest.xml
index 490dd6a1e7..79aaf3f5d4 100644
--- a/samples/android/tutorial-1-camerapreview/gradle/AndroidManifest.xml
+++ b/samples/android/tutorial-1-camerapreview/gradle/AndroidManifest.xml
@@ -8,7 +8,9 @@
         android:icon="@drawable/icon"
         android:theme="@android:style/Theme.NoTitleBar.Fullscreen" >
 
-        <activity android:name="Tutorial1Activity"
+        <activity
+                  android:exported="true"
+                  android:name="Tutorial1Activity"
                   android:label="@string/app_name"
                   android:screenOrientation="landscape"
                   android:configChanges="keyboardHidden|orientation">
diff --git a/samples/android/tutorial-2-mixedprocessing/gradle/AndroidManifest.xml b/samples/android/tutorial-2-mixedprocessing/gradle/AndroidManifest.xml
index 574facc3d5..90d4bbf8dc 100644
--- a/samples/android/tutorial-2-mixedprocessing/gradle/AndroidManifest.xml
+++ b/samples/android/tutorial-2-mixedprocessing/gradle/AndroidManifest.xml
@@ -7,7 +7,9 @@
         android:label="@string/app_name"
         android:icon="@drawable/icon">
 
-        <activity android:name="Tutorial2Activity"
+        <activity
+                  android:exported="true"
+                  android:name="Tutorial2Activity"
                   android:label="@string/app_name"
                   android:screenOrientation="landscape"
                   android:configChanges="keyboardHidden|orientation">
diff --git a/samples/android/tutorial-3-cameracontrol/gradle/AndroidManifest.xml b/samples/android/tutorial-3-cameracontrol/gradle/AndroidManifest.xml
index d8baa0859c..87cbc760b0 100644
--- a/samples/android/tutorial-3-cameracontrol/gradle/AndroidManifest.xml
+++ b/samples/android/tutorial-3-cameracontrol/gradle/AndroidManifest.xml
@@ -7,7 +7,9 @@
         android:label="@string/app_name"
         android:icon="@drawable/icon">
 
-        <activity android:name="Tutorial3Activity"
+        <activity
+                  android:exported="true"
+                  android:name="Tutorial3Activity"
                   android:label="@string/app_name"
                   android:screenOrientation="landscape"
                   android:configChanges="keyboardHidden|orientation">
diff --git a/samples/android/tutorial-4-opencl/gradle/AndroidManifest.xml b/samples/android/tutorial-4-opencl/gradle/AndroidManifest.xml
index f44d9a5dcc..7cef5cc675 100644
--- a/samples/android/tutorial-4-opencl/gradle/AndroidManifest.xml
+++ b/samples/android/tutorial-4-opencl/gradle/AndroidManifest.xml
@@ -1,31 +1,32 @@
 <?xml version="1.0" encoding="utf-8"?>
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="org.opencv.samples.tutorial4"
-    android:versionCode="1"
-    android:versionName="1.0" >
-
-    <uses-sdk
-        android:minSdkVersion="14"
-        android:targetSdkVersion="21" />
-
-    <uses-feature android:glEsVersion="0x00020000" android:required="true"/>
-    <uses-feature android:name="android.hardware.camera"/>
-    <uses-feature android:name="android.hardware.camera2" android:required="false"/>
-    <uses-permission android:name="android.permission.CAMERA"/>
-
-    <application
-        android:allowBackup="true"
-        android:icon="@drawable/icon">
-        <activity
-            android:name=".Tutorial4Activity"
-            android:label="@string/app_name"
-            android:screenOrientation="landscape"
-            android:configChanges="keyboardHidden|orientation">
-            <intent-filter>
-                <action android:name="android.intent.action.MAIN" />
-                <category android:name="android.intent.category.LAUNCHER" />
-            </intent-filter>
-        </activity>
-    </application>
-
-</manifest>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="org.opencv.samples.tutorial4"
+    android:versionCode="1"
+    android:versionName="1.0" >
+
+    <uses-sdk
+        android:minSdkVersion="14"
+        android:targetSdkVersion="21" />
+
+    <uses-feature android:glEsVersion="0x00020000" android:required="true"/>
+    <uses-feature android:name="android.hardware.camera"/>
+    <uses-feature android:name="android.hardware.camera2" android:required="false"/>
+    <uses-permission android:name="android.permission.CAMERA"/>
+
+    <application
+        android:allowBackup="true"
+        android:icon="@drawable/icon">
+        <activity
+            android:exported="true"
+            android:name=".Tutorial4Activity"
+            android:label="@string/app_name"
+            android:screenOrientation="landscape"
+            android:configChanges="keyboardHidden|orientation">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+    </application>
+
+</manifest>