[7947] Feature: Blank out app preview screen when switching apps on mobile

Signed-off-by: Andrey Shovkoplyas <motor4ik@gmail.com>

android/app/src/main/java/im/status/ethereum/MainActivity.java

@@ -12,8 +12,10 @@ import android.content.pm.PackageManager;
 import android.net.Uri;
 import android.os.Build;
 import android.os.Looper;
+import android.preference.PreferenceManager;
 import android.support.v4.app.ActivityCompat;
 import android.util.Log;
+import android.view.WindowManager;
 import android.content.Intent;
 import android.content.SharedPreferences;
 import android.content.res.Configuration;
@@ -109,7 +111,7 @@ public class MainActivity extends ReactActivity
         final ActivityManager activityManager = getActivityManager();
         Log.v("RNBootstrap", "Available system memory "+getAvailableMemory(activityManager).availMem + ", maximum usable application memory " + activityManager.getLargeMemoryClass()+"M");
 
-
+        setSecureFlag();
         SplashScreen.show(this, true);
         super.onCreate(savedInstanceState);
 
@@ -202,6 +204,16 @@ public class MainActivity extends ReactActivity
         editor.commit();
     }
 
+    private void setSecureFlag() {
+        final SharedPreferences sharedPrefs = PreferenceManager.getDefaultSharedPreferences(this);
+        final boolean setSecure = sharedPrefs.getBoolean("BLANK_PREVIEW", false);
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH && setSecure) {
+            getWindow().addFlags(WindowManager.LayoutParams.FLAG_SECURE);
+        } else {
+            getWindow().clearFlags(WindowManager.LayoutParams.FLAG_SECURE);
+        }
+    }
+
     @TargetApi(Build.VERSION_CODES.M)
     public void requestPermissions(String[] permissions, int requestCode, PermissionListener listener) {
         mPermissionListener = listener;

ios/StatusIm/AppDelegate.m

@@ -20,7 +20,10 @@
 #import "RNFirebaseNotifications.h"
 #import "RNFirebaseMessaging.h"
 
-@implementation AppDelegate
+@implementation AppDelegate 
+{
+    UIView *_blankView;
+}
 
 - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
 {
@@ -47,6 +50,10 @@
     RCTSetLogThreshold(RCTLogLevelTrace);
   }
 
+  NSDictionary *appDefaults = [NSDictionary
+      dictionaryWithObject:[NSNumber numberWithBool:NO] forKey:@"BLANK_PREVIEW"];
+  [[NSUserDefaults standardUserDefaults] registerDefaults:appDefaults];
+
   RCTBridge *bridge = [[RCTBridge alloc] initWithDelegate:self launchOptions:launchOptions];
   RCTRootView *rootView = [[RCTRootView alloc] initWithBridge:bridge
                                                       moduleName:@"StatusIm"
@@ -54,6 +61,10 @@
   rootView.backgroundColor = [[UIColor alloc] initWithRed:1.0f green:1.0f blue:1.0f alpha:1];
 
   self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
+  _blankView = [[UIView alloc]initWithFrame:self.window.frame];
+  _blankView.backgroundColor = [UIColor whiteColor];
+  _blankView.alpha = 0;
+
   UIViewController *rootViewController = [UIViewController new];
   rootViewController.view = rootView;
   self.window.rootViewController = rootViewController;
@@ -101,4 +112,25 @@
 #endif
 }
 
+- (void)applicationWillResignActive:(UIApplication *)application {
+  if ([[NSUserDefaults standardUserDefaults] boolForKey:@"BLANK_PREVIEW"]) {
+    [self.window addSubview:_blankView];
+    [self.window bringSubviewToFront:_blankView];
+
+    [UIView animateWithDuration:0.5 animations:^{
+      _blankView.alpha = 1;
+    }];
+  } 
+}
+
+- (void)applicationDidBecomeActive:(UIApplication *)application {
+  if ([[NSUserDefaults standardUserDefaults] boolForKey:@"BLANK_PREVIEW"]) {
+    [UIView animateWithDuration:0.5 animations:^{
+      _blankView.alpha = 0;
+    } completion:^(BOOL finished) {
+      [_blankView removeFromSuperview];
+    }];
+  }
+}
+
 @end

modules/react-native-status/android/src/main/java/im/status/ethereum/module/StatusModule.java

@@ -9,8 +9,10 @@ import android.content.SharedPreferences;
 import android.net.Uri;
 import android.os.Build;
 import android.os.Environment;
+import android.preference.PreferenceManager;
 import android.support.v4.content.FileProvider;
 import android.util.Log;
+import android.view.Window;
 import android.view.WindowManager;
 import android.webkit.CookieManager;
 import android.webkit.CookieSyncManager;
@@ -943,6 +945,32 @@ class StatusModule extends ReactContextBaseJavaModule implements LifecycleEventL
         callback.invoke(uniqueID);
     }
 
+    @ReactMethod
+    public void setBlankPreviewFlag(final Boolean blankPreview) {
+        final SharedPreferences sharedPrefs = PreferenceManager.getDefaultSharedPreferences(this.reactContext);
+        sharedPrefs.edit().putBoolean("BLANK_PREVIEW", blankPreview).commit();
+        setSecureFlag();
+    }
+
+    private void setSecureFlag() {
+        final SharedPreferences sharedPrefs = PreferenceManager.getDefaultSharedPreferences(this.reactContext);
+        final boolean setSecure = sharedPrefs.getBoolean("BLANK_PREVIEW", true);
+        final Activity activity = this.reactContext.getCurrentActivity();
+        if (activity != null) {
+            activity.runOnUiThread(new Runnable() {
+                @Override
+                public void run() {
+                    final Window window = activity.getWindow();
+                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH && setSecure) {
+                        window.addFlags(WindowManager.LayoutParams.FLAG_SECURE);
+                    } else {
+                        window.clearFlags(WindowManager.LayoutParams.FLAG_SECURE);
+                    }
+                }
+            });
+        }
+    }
+
   private Boolean is24Hour() {
     return android.text.format.DateFormat.is24HourFormat(this.reactContext.getApplicationContext());
   }

modules/react-native-status/ios/RCTStatus/RCTStatus.m

@@ -539,6 +539,15 @@ RCT_EXPORT_METHOD(getDeviceUUID:(RCTResponseSenderBlock)callback) {
     callback(@[Identifier]);
 }
 
+RCT_EXPORT_METHOD(setBlankPreviewFlag:(BOOL *)newValue)
+{
+  NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
+
+  [userDefaults setBool:newValue forKey:@"BLANK_PREVIEW"];
+
+  [userDefaults synchronize];
+}
+
 - (bool) is24Hour
 {
     NSString *format = [NSDateFormatter dateFormatFromTemplate:@"j" options:0 locale:[NSLocale currentLocale]];

src/status_im/accounts/core.cljs

@@ -16,6 +16,11 @@
  (fn [on]
    (native-module/chaos-mode-update on (constantly nil))))
 
+(re-frame/reg-fx
+ ::blank-preview-flag-changed
+ (fn [flag]
+   (native-module/set-blank-preview-flag flag)))
+
 (fx/defn show-mainnet-is-default-alert [{:keys [db]}]
   (let [shown-version (get-in db [:account/account :mainnet-warning-shown-version])
         current-version build/version]
@@ -98,6 +103,14 @@
                                      (assoc settings :web3-opt-in? opt-in)
                                      {})))
 
+(fx/defn switch-preview-privacy-mode [{:keys [db] :as cofx} private?]
+  (let [settings (get-in db [:account/account :settings])]
+    (fx/merge cofx
+              {::blank-preview-flag-changed private?}
+              (accounts.update/update-settings
+               (assoc settings :preview-privacy? private?)
+               {}))))
+
 (fx/defn update-recent-stickers [cofx stickers]
   (accounts.update/account-update cofx
                                   {:recent-stickers stickers}

src/status_im/constants.cljs

@@ -109,6 +109,7 @@
 
 (defn default-account-settings []
   {:web3-opt-in? true
+   :preview-privacy? false
    :wallet       {:visible-tokens {:testnet #{:STT :HND}
                                    :mainnet #{:SNT}
                                    :rinkeby #{:MOKSHA :KDO}

src/status_im/events.cljs

@@ -214,6 +214,11 @@
  (fn [cofx [_ opt-in]]
    (accounts/switch-web3-opt-in-mode cofx opt-in)))
 
+(handlers/register-handler-fx
+ :accounts.ui/preview-privacy-mode-switched
+ (fn [cofx [_ private?]]
+   (accounts/switch-preview-privacy-mode cofx private?)))
+
 (handlers/register-handler-fx
  :accounts.ui/wallet-set-up-confirmed
  (fn [cofx [_ modal?]]

src/status_im/native_module/core.cljs

@@ -88,6 +88,9 @@
 (defn get-device-UUID [callback]
   (native-module/get-device-UUID callback))
 
+(defn set-blank-preview-flag [flag]
+  (native-module/set-blank-preview-flag flag))
+
 (defn is24Hour []
   (native-module/is24Hour))
 

src/status_im/native_module/impl/module.cljs

@@ -133,6 +133,9 @@
    (fn [UUID]
      (callback (string/upper-case UUID)))))
 
+(defn set-blank-preview-flag [flag]
+  (.setBlankPreviewFlag status flag))
+
 (defn extract-group-membership-signatures [signature-pairs callback]
   (when status
     (.extractGroupMembershipSignatures status signature-pairs callback)))

src/status_im/ui/screens/profile/user/views.cljs

@@ -101,7 +101,7 @@
                                                         :value   value}]))
 
 (defn- my-profile-settings [{:keys [seed-backed-up? mnemonic]}
-                            account
+                            {:keys [settings] :as account}
                             currency
                             logged-in?
                             extensions]
@@ -144,6 +144,11 @@
        :action-fn           #(re-frame/dispatch [:navigate-to :installations])
        :accessibility-label :pairing-settings-button}]
      [profile.components/settings-item-separator]
+     [profile.components/settings-switch-item
+      {:label-kw  :t/preview-privacy
+       :value     (boolean (:preview-privacy? settings))
+       :action-fn #(re-frame/dispatch [:accounts.ui/preview-privacy-mode-switched %])}]
+     [profile.components/settings-item-separator]
      [profile.components/settings-item
       {:label-kw            :t/dapps-permissions
        :accessibility-label :dapps-permissions-button

test/cljs/status_im/test/sign_in/data.cljs

@@ -104,6 +104,7 @@
    :last-request                         nil
    :desktop-notifications?               false
    :settings                             {:web3-opt-in? true
+                                          :preview-privacy? true
                                           :fleet        :eth.beta
                                           :wallet       {:visible-tokens {:testnet #{:STT
                                                                                      :HND}

translations/en.json

@@ -784,6 +784,7 @@
     "currency-display-name-usd": "United States Dollar",
     "currency-display-name-uah": "Ukraine Hryvnia",
     "web3-opt-in": "Browser privacy mode",
+    "preview-privacy": "Preview privacy mode",
     "recover-password-invalid": "This account already exists but passwords do not match",
     "recover-keycard-account-not-supported": "Recovering keycard account with password is not supported",
     "members-active-none": "no members",