Titanium module - life cycle events not called - module

I am building a Titanium module for the Android platform and I want to use the life cycle events of the module (i.e. onDestroy, onPause, etc). I tried to use them by overriding these life cycle events in the module class like this:
#Kroll.module(name="custom", id="vub.ac.be.custom")
public class CustomModule extends KrollModule {
private static final String TAG = "customModule";
#Kroll.onAppCreate
public static void onAppCreate(TiApplication app) {
}
private void destroyServices(){
//...
}
#Override
public void onStop(Activity activity) {
Log.d(TAG, "STOPPING");
destroyServices();
super.onStop(activity);
}
#Override
public void onPause(Activity activity) {
Log.d(TAG, "[MODULE LIFECYCLE EVENT] pause");
super.onPause(activity);
}
#Override
public void onResume(Activity activity) {
Log.d(TAG, "[MODULE LIFECYCLE EVENT] resume");
super.onResume(activity);
}
#Override
public void onDestroy(Activity activity) {
Log.d(TAG, "[MODULE LIFECYCLE EVENT] destroy");
destroyService();
super.onDestroy(activity);
}
}
but when I opening and closing the application, these life cycle events are never called. Does anybody know how to use them, because only if I can use them I will be able to build the module I want. Thanks

Could this be the origin of my problems: inline link moddevguide
https://github.com/appcelerator/titanium_modules/blob/master/moddevguide/mobile/android/src/ti/moddevguide/ModdevguideModule.java
on line 72 they describe the following:
// Lifecycle
// NOTES:
//
// 1. Modules are created in the root context
// 2. Using navBarHidden (or fullscreen or modal) causes the window, when opened, to run in a new Android Activity.
// 3. The root context/activity will be stopped when a new activity is launched
// 4. Lifecycle notifications will NOT be received while the root activity is stopped.
I run the module in an application that uses navBarHidden, so as described a new android activity wil be started and the root activity is stopped. Whenever the root activity is stopped, the lifecycle notifications are received. Can anyone confirm this and does anybody know how to solve this? thanks

What version of SDK are you using? On 3.3.0 lifecycle callbacks is calling regardless to navigation bar hidden.

Related

Xamarin.Forms Communication Between Two Pages Within Same App on Different Devices

Technologies, frameworks and devices I'm using:
Framework: Xamarin.Forms
IDE: Visual Studio 2022
Physical Device (smartphone): Zebra TC26 (Android 10)
Physical Device (smartwatch): Samsung Galaxy Watch4 (Android 11)
Problem definition
Currently I have a test Xamarin.Forms project that consists of two different UIs (XAML files):
User Interface 1: HomePage.XAML - This screen should be displayed on the smartphone
User Interface 2: WatchScreen.XAML - This screen should be displayed on the smartwatch
With code below I make sure HomePage.XAML is deployed to a smartphone and watchscreen is deployed to a smartwatch:
Page homePage = new NavigationPage(new HomePage());
// BuildVersionCodes.R is a reference to Android version 11 (mostly now used by Wear OS 3.x)
if (Build.VERSION.SdkInt == BuildVersionCodes.R)
{
// SM-R870 is a reference to the Samsung Galaxy Watch4
// Note: This is needed to ensure the UI is specific to the UI of a smartwatch
if (Build.Model == "SM-R870")
{
Page watchScreen = new NavigationPage(new WatchScreen());
MainPage = watchScreen;
}
}
else
{
MainPage = homePage;
}
Now I want to make these pages on different devices communicate with each other. HomePage.xaml exists within the main Xamarin.Forms project as well as WatchScreen.xaml.
The way I want them to communicate with each other is by sending a message or something. A Xamarin.Forms project also comes with a native project. In this native Xamarin.Android project I try to retrieve inside the MainActivity.cs the button that exists within the main project by using (in WatchScreen.xaml this button exists and in WatchScreen.xaml.cs I have a method that gives this button back).
Method in WatchScreen.xaml.cs that gives button back:
public Button GetSendButtonFromWearableUI() => btnSendMessage;
In MainActivity.cs I get this method by using:
Button button = (App.Current.MainPage.Navigation.NavigationStack.LastOrDefault() as WatchScreen)
.GetSendButtonFromWearableUI();
Whenever I click on the button by doing this:
button.Clicked += delegate
{
SendData();
};
Some data should be sent from MainActivity.cs and catched by HomePage.xaml and displayed on it. I tried several approaches but I didn't succeed in achieving what needs to happen.. Therefore, I'm wondering if you guys could help me out with this and would be much appreciated.
In the meantime I've been investigating this issue and came up with a solution. Follow steps below to get the same result. To make this solution work I've combined the Wearable Data Layer API from Google and MessagingCenter from Microsoft.
Also the example below shows only the communication from the smartwatch to the smartphone. In order to reverse processes you can put the send button on the HomePage instead of the smartwatch screen and make sure to subscribe to the correct messages.
One last note: keep in mind that code used below from Google is deprecated but it still works...
References used to make this work:
Syncing Data Between Wearable and Handheld Devices Using Xamarin in Android
Installed dependencies on the Xamarin.Android project within Xamarin.Forms project:
Xamarin.Android.Support.v4
Xamarin.GooglePlayServices.Base
Xamarin.GooglePlayServices.Wearable
MessageKeys.cs
This class is used to declare message keys that are being used to send and receive messages between devices.
public class MessageKeys
{
public const string Smartwatch = "Smartwatch";
public const string Smartphone = "Smartphone";
}
Xamarin.Forms (Base project) - App.xaml.cs
In the App.xaml.cs, as pointed out earlier, I'm making sure the wearable UI displays WatchScreen.xaml and any other devices display regular Android UI -> HomePage.xaml.
Xamarin.Forms (Base project) - WatchScreen.xaml.cs
Send message from Wearable device to Android smartphone.
private void btnSendMessage_Clicked(object sender, EventArgs e)
{
MessagingCenter.Send(Xamarin.Forms.Application.Current, MessageKeys.Smartwatch);
}
Xamarin.Forms (Base project) - HomePage.xaml.cs
public HomePage()
{
InitializeComponent();
MessagingCenter.Subscribe<Xamarin.Forms.Application>(Xamarin.Forms.Application.Current, MessageKeys.Smartphone, (sender) =>
{
DisplayAlert("Message", "Wearable message received!", "OK");
});
}
Xamarin.Forms (Native Android Project) - MainActivity.cs
Within MainActivity.cs I implement the following interfaces:
public class MainActivity : WearableActivity, DataClient.IOnDataChangedListener,
GoogleApiClient.IConnectionCallbacks, GoogleApiClient.IOnConnectionFailedListener
Variables:
private GoogleApiClient client;
const string syncPath = "/[project name]/[subdirectory for watch]";
Internal class 'MessageReceiver' for receiving broadcast messages:
[BroadcastReceiver]
public class MessageReciever : BroadcastReceiver
{
MainActivity main;
public MessageReciever() { }
public MessageReciever(MainActivity owner) { this.main = owner; }
public override void OnReceive(Context context, Intent intent)
{
main.ProcessMessage(intent);
}
}
Registering receiver (to receive through Wearable Data Layer API), creating Google Client and Subscribing to smartwatch message (to retrieve message through MessagingCenter)
protected override void OnCreate(Bundle bundle)
{
IntentFilter filter = new IntentFilter(Intent.ActionSend);
MessageReciever receiver = new MessageReciever(this);
LocalBroadcastManager.GetInstance(this).RegisterReceiver(receiver, filter);
client = new GoogleApiClient.Builder(this, this, this)
.AddApi(WearableClass.Api)
.Build();
MessagingCenter.Subscribe<Xamarin.Forms.Application>(Xamarin.Forms.Application.Current, MessageKeys.Smartwatch, (sender) =>
{
SendData();
});
}
ProcessMessage method: sends received message from wearable to smartphone
public void ProcessMessage(Intent intent)
{
// For now I'm not sending the payload...
string message = intent.GetStringExtra("WearMessage");
MessagingCenter.Send(Xamarin.Forms.Application.Current, MessageKeys.Smartphone);
}
SendData(), OnStart(), OnStop(), OnDataChanged (didn't do anything with this part, because this is to receive messages outside the project and I don't need it for now), OnConnected(), OnConnectionSuspended(), OnConnectionFailed():
See the reference to see what code has been used, since code is exactly the same... P.S.: one thing for SendData has been changed. If you want to keep sending data, remove 'client.Disconenct()' from finally after the try and catch block.
Xamarin.Forms (Native Android Project) - WearableService inherits from WearableListenerService:
WearableService is a new class and created within the native project. Also for this part see the reference, because it's the exact same code being used within my project.
To get an overall overview of what's happening, I've visualized this in the diagram below: (example shows how communication works from smartwatch to smartphone)
If you want to communicate from smartphone to smartwatch, you could do something like this:
That's it guys. Now you will receive messages within the same application using the Wearable Data Layer API and MessagingCenter. Instead of having separate projects, we just use separate UIs to make this happen...

Only one callback may be registered to a function in a native module react native error

I recently added an android native module to my which listens on timezone and time changed broadcasts from the system and allows the app to perform some operations. The native module looks like this
public class TimezoneHandlerModule extends ReactContextBaseJavaModule {
private final Context context;
private final TimezoneChangeBroadcastReceiver timezoneChangeBroadcastReceiver;
private Callback onTimezoneChangeCallback;
public TimezoneHandlerModule(ReactApplicationContext reactContext) {
super(reactContext);
this.context = reactContext;
this.timezoneChangeBroadcastReceiver = new TimezoneChangeBroadcastReceiver();
}
private void registerForTimezoneChangeHandler() {
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(Intent.ACTION_TIME_CHANGED);
intentFilter.addAction(Intent.ACTION_TIMEZONE_CHANGED);
getReactApplicationContext().registerReceiver(timezoneChangeBroadcastReceiver, intentFilter);
}
private void unregisterTimezoneChangeHandler() {
getReactApplicationContext().unregisterReceiver(timezoneChangeBroadcastReceiver);
}
public void setOnTimezoneChangeCallback(Callback onTimezoneChangeCallback) {
this.onTimezoneChangeCallback = onTimezoneChangeCallback;
}
/**
* #return the name of this module. This will be the name used to {#code require()} this module
* from javascript.
*/
#Override
public String getName() {
return "TimezoneHandler";
}
#ReactMethod
public void start(Callback onChange) {
Log.d(getName(), "Starting the timezone change handler");
this.registerForTimezoneChangeHandler();
this.setOnTimezoneChangeCallback(onChange);
}
#ReactMethod
public void stop() {
Log.d(getName(), "Stopping the timezone change handler");
this.unregisterTimezoneChangeHandler();
}
private class TimezoneChangeBroadcastReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
Log.d(getName(), "Received broadcast for timezone/time change " + intent.getAction());
final String action = intent.getAction();
if (action.equals(Intent.ACTION_TIME_CHANGED) || action.equals(Intent.ACTION_TIMEZONE_CHANGED)) {
TimezoneHandlerModule.this.onTimezoneChangeCallback.invoke();
}
}
}
}
Two react methods are exposed start and stop. start takes a function as a parameter which is invoked whenever a broadcast for timezone changed or time changed is received. After hooking up the native module and starting the app in emulator, I opened Settings and change the timezone and I can see that the relevant logs are printed.
11-24 17:07:21.837 1597-1597/com.xyz D/TimezoneHandler: Received broadcast for timezone/time change
11-24 17:07:21.837 1597-1907/com.xyz I/ReactNativeJS: Detected timezone change
When I change the timezone again, I see below error in the logcat output
1-24 17:22:42.356 1597-1597/com.galarmapp D/TimezoneHandler: Received broadcast for timezone/time change
11-24 17:22:42.365 1597-1907/com.galarmapp E/ReactNativeJS: The callback start() exists in module TimezoneHandler, but only one callback may be registered to a function in a native module.
11-24 17:22:42.367 1597-1908/com.galarmapp E/unknown:React: The callback start() exists in module TimezoneHandler, but only one callback may be registered to a function in a native module., stack:
__invokeCallback#12814:10
<unknown>#12685:24
guard#12604:3
invokeCallbackAndReturnFlushedQueue#12684:6
From the error message, it seems as if I am trying to attach a separate callback to the start function but I am not doing any such thing. I am calling the start method in the componentWillMount of the top level component and have confirmed that it is not called twice. I see that other people have also seen this error while trying different things but still don't understand the reason behind the problem.
Please share if you have any insights.
According to the documentation http://facebook.github.io/react-native/docs/native-modules-android.html#callbacks - "A native module is supposed to invoke its callback only once. It can, however, store the callback and invoke it later." Once you have done invoke() on the callback, you cannot use it again.
This particular use case of time zone change is better solved by sending events to javascript. See this documentation http://facebook.github.io/react-native/docs/native-modules-android.html#sending-events-to-javascript

Adding a page before the hub page in a Windows Phone 8.1 store app

I'm building a Windows Universal Store App, concentrating first on the Windows Phone 8.1 app. I'm basing my app on a hub app. I want to add a splash page to the app startup to replace the static splash screen with a XAML based animation. I am confused by navigation since it all seems to be set up and owned by the hub page.
I have looked at
Mike Taulty's blog post about Windows/Phone 8.1–Frame, Page, NavigationHelper, SuspensionManager;
Quickstart: Navigating between pages;
How to extend the splash screen; and
Navigation Patterns
In fact the last of those explicitly states that "hub pages are the user's entry point to the app".
How do I add pages to my hub app that the user will encounter before the hub, like a splash page or a logon screen?
Typically no sooner had I posted the question than I saw where to find the answer. When NavigationHelper is added to the project along with the hub page it includes comments explaining how to use it:
To make use of NavigationHelper, follow these two steps or
start with a BasicPage or any other Page item template other than BlankPage.
1) Create an instance of the NavigationHelper somewhere such as in the
constructor for the page and register a callback for the LoadState and
SaveState events.
public MyPage()
{
this.InitializeComponent();
var navigationHelper = new NavigationHelper(this);
this.navigationHelper.LoadState += navigationHelper_LoadState;
this.navigationHelper.SaveState += navigationHelper_SaveState;
}
private async void navigationHelper_LoadState(object sender, LoadStateEventArgs e)
{
}
private async void navigationHelper_SaveState(object sender, LoadStateEventArgs e)
{
}
2) Register the page to call into the NavigationHelper whenever the page participates
in navigation by overriding the Windows.UI.Xaml.Controls.Page.OnNavigatedTo
and Windows.UI.Xaml.Controls.Page.OnNavigatedFrom events.
protected override void OnNavigatedTo(NavigationEventArgs e)
{
navigationHelper.OnNavigatedTo(e);
}
protected override void OnNavigatedFrom(NavigationEventArgs e)
{
navigationHelper.OnNavigatedFrom(e);
}
That boiler-plate code only required slight changes in my page: take out the async, and make navigationHelper an instance variable.
Then to start in another page follow the instructions in Set start page in Windows Phone 8.1 universal app to edit App.xaml.cs thus:
#if WINDOWS_PHONE_APP
if (!rootFrame.Navigate(typeof(SplashPage), e.Arguments))
{
throw new Exception("Failed to create initial page");
}
#endif
#if WINDOWS_APP
if (!rootFrame.Navigate(typeof(HubPage), e.Arguments))
{
throw new Exception("Failed to create initial page");
}
#endif
Then in SplashPage.xaml.cs when I need to navigate to the hub page I add
if (rootFrame.Navigate(typeof(HubPage)))
{
Window.Current.Content = rootFrame;
}
else
{
throw new Exception("Failed to create hub page");
}

Animation not starting until UI updates or touch event

I have a strange problem with an AlphaAnimation. It is supposed to run repeatedly when an AsyncTask handler is called.
However, the first time the handler is called in the Activity, the animation won't start unless I touch the screen or if the UI is updated (by pressing the phone's menu button for example).
The strange part is that once the animation has run at least once, it will start without problem if the handler is called again.
Here's what the code looks like:
// AsyncTask handler
public void onNetworkEvent()
{
this.runOnUiThread(new Runnable() {
#Override
public void run()
{
flashScreen(Animation.INFINITE);
}
});
}
// Called method
private void flashScreen(int repeatCount)
{
final View flashView = this.findViewById(R.id.mainMenuFlashView);
AlphaAnimation alphaAnimation = new AlphaAnimation(1, 0);
alphaAnimation.setRepeatCount(repeatCount);
alphaAnimation.setRepeatMode(Animation.RESTART);
alphaAnimation.setDuration(300);
alphaAnimation.setInterpolator(new DecelerateInterpolator());
alphaAnimation.setAnimationListener(new Animation.AnimationListener() {
#Override
public void onAnimationStart(Animation animation)
{
flashView.setVisibility(View.VISIBLE);
}
#Override
public void onAnimationEnd(Animation animation)
{
flashView.setVisibility(View.GONE);
}
#Override
public void onAnimationRepeat(Animation animation) { }
});
flashView.startAnimation(alphaAnimation);
}
I have noticed that runOnUIThread isn't necessary (same results occur if I don't use it), but I prefer keeping it as I'm not on the UI thread.
Any ideas on what could cause this?
A little more research showed that my problem was the same a this question:
Layout animation not working on first run
The flashView's visibility was set to GONE by default (causing the Animation not to start immediately as the View had never been rendered), so I just need to set it to INVISIBLE before calling flashView.startAnimation()
If setting the View to VISIBLE won't work, as was in my case, it helped for me to call requestLayout() before starting the Animation, like so:
Animation an = new Animation() {
...
view.requestLayout();
view.startAnimation(an);
In my case, my View was 0dip high which prevented onAnimationStart from being called, this helped me around that problem.
This worked for me:
view.setVisibility(View.VISIBLE);
view.startAnimation(animation);
I had to set the view to VISIBLE (not INVISIBLE, neither GONE), causing the view renderization needed to animate it.
That's not an easy one. Till you got a real answer : The animation start is triggered by onNetworkEvent. As we don't know the rest of the code, you should look there, try to change onNetworkEvent by an other event that you can easily identify, just to debug if the rest of the code is ok or if it's just the trigger that is responsible for it.
May be it will help someone, because previous answers not helped me.
My animation was changing height of view (from 0 to it's real height and back) on click - expand and collapse animations.
Nothing worked until i added listener and set visibility to GONE, when animation ends:
collapseAnim.setAnimationListener(new Animation.AnimationListener() {
#Override
public void onAnimationStart(Animation animation) {
}
#Override
public void onAnimationEnd(Animation animation) {
view.setVisibility(View.GONE);
}
#Override
public void onAnimationRepeat(Animation animation) {
}
});
And when expand just set it to VISIBLE before animation:
view.setVisibility(View.VISIBLE);
view.startAnimation(expandAnim);

null pointer exception on android asynctaskloader

I'm trying to do a twitter android application. I'm still working on the login.
So I'm using asynctaskloader after a friend suggested me to use it. I believe I get a null pointer exception at this line:
this.consumer = (OAuthConsumer) new getCommonsHttpOAuthConsumer(context);
here's my asynctaskloader class:
class getCommonsHttpOAuthConsumer extends AsyncTaskLoader{
public getCommonsHttpOAuthConsumer(Context context) {
super(context);
// TODO Auto-generated constructor stub
}
#Override
public OAuthConsumer loadInBackground() {
// TODO Auto-generated method stub
return new CommonsHttpOAuthConsumer(Constants.CONSUMER_KEY, Constants.CONSUMER_SECRET);
}
}
what am I doing wrong? do you guys need to see more code?
thank you.
You're not using the loader class right.
You need to call the LoaderManager with this line:
getLoaderManager().initLoader(ID_FOR_THIS_LOADER, DATA_BUNDLE, CALLBACK);
If you're in a Fragment you need to add getActivity() at the beginning, and if you are using the android.support.v4.jar, you will call getSupportLoaderManager().
You place this line in your onCreate or onResume method. It will simply notify your activity that you want to start a new loader.
After that you'll need to implement the callbacks notifying that your loader is created/finished. This callbacks are implemented by the object you specified as third parameter (CALLBACK). It can be an activity, a fragment... You will find the syntax online.
Here is what it will look like:
// Callback called by your Activity
#Override
public Loader<OAuthConsumer> onCreateLoader(int id, Bundle arg1) {
loader = new getCommonsHttpOAuthConsumer();
return loader;
// After this method you're going in loadInBackground()
}
#Override
public void onLoadFinished(Loader<OAuthConsumer> loader, OAuthConsumer pl) {
// After loadInBackground() you arrive here, with your new object OAuthConsumer
this.consumer = pl;
}
It should work like this, hope it helps!