The equivalent to onResume() in Windows Phone 7 - windows-phone-7

I'm looking for some app life cycle help from the wp7 experts. My app has a refresh step in a specific page but I only want to launch this when the user brings the app to life from the background.
Note- The life cycle step I'm looking for isn't called when the page is init() only when I'm navigated (back) to or the user has taken a phone call and then re-opens the app (keeping the same page open)
Thank you in advance

what you are looking for is called Tombstoning and you can find a great article at http://wildermuth.com/2010/10/17/Architecting_WP7_-_Part_5_of_10_Tombstoning
The events are:
Launching (opened from tile)
Deactivated (user takes a call or something)
Activated (back from the call)
Closing (Leaves you app via the "Back" button)
You are looking for the Activated event. These are in your App.xaml.cs/vb file. Hook into the event, and update your data model. When your page is bound to that model it will get the data.
If you are not using MVVM, and can't really refresh from that event, you can do it using the PhoneApplicationService.Current.StartupMode property. It has two options Activate (what you are looking for) and Launch (loaded fresh from the tile). It would look something like
Init()
{
if (PhoneApplicationService.Current.StartupMode == StartupMode.Activate)
{
Refresh()
}
}

Related

Xamarin Forms WebView open external link

I have a webview inside my application and when an external link is clicked (that in normal browser is open in a new tab), I can't then go back to my website.
It is possible when a new tab is open to have the menu closed that tab like Gmail do ?
The objective is that, whenever a link is clicked, the user would have the choice to choose which option to view the content with, e.g. Clicking a link would suggest open youtube app or google chrome. The purpose is to appear the google chrome option
Or what suggestions do you have to handle this situation ?
If I understood you correctly, you want to have the option to select how to open the web link - inside your app, or within another app's (browser) context.
If this is correct, then you can use Xamarin.Essentials: Browser functionality.
public async Task OpenBrowser(Uri uri)
{
await Browser.OpenAsync(uri, BrowserLaunchMode.SystemPreferred);
}
Here the important property is the BrowserLaunchMode flag, which you can learn more about here
Basically, you have 2 options - External & SystemPreferred.
The first one is clear, I think - it will open the link in an external browser.
The second options takes advantage of Android's Chrome Custom Tabs & for iOS - SFSafariViewController
P.S. You can also customise the PreferredToolbarColor, TitleMode, etc.
Edit: Based from your feedback in the comments, you want to control how to open href links from your website.
If I understood correctly, you want the first time that you open your site, to not have the nav bar at the top, and after that to have it. Unfortunately, this is not possible.
You can have the opposite behaviour achieved - the first time that you open a website, to have the nav bar and if the user clicks on any link, to open it externally (inside a browser). You have 2 options for this:
To do it from your website - change the a tag's target to be _blank like this;
To do it from your mobile app - create a Custom renderer for the WebView. In the Android project's renderer implementation, change the Control's WebViewClient like so:
public class CustomWebViewClient : WebViewClient
{
public override bool ShouldOverrideUrlLoading(Android.Webkit.WebView view, IWebResourceRequest request)
{
Intent intent = new Intent(Intent.ActionView, request.Url);
CrossCurrentActivity.Current.StartActivity(intent);
return true;
}
}

Unity - Detect if Game Center is available

My Game is using Unity API to call Game Center and I want to use it like "Archero".
i want to make it possible:
if Game Center is available: login and show banner...etc.
if not: just give me a callback, DO NOT show the Game Center Authenticate Panel.
but no matter how I call the authentication function, it ALWAYS pop the Authenticate panel.
is there any solution to detect if the Game Center is available?
By the way, someones said that when user cancel Authentication 3 times, Game Center will block user.
If i can do that by code will be pretty useful, i can use it to deal with my problems
Here is my Authenticate Code:
public void OnClick_Authenticate()
{
try
{
Social.localUser.Authenticate(ProcessAuthentication);
}
catch
{
ActiveCallback();
}
}
I don't think that is possible/intended. You're talking about the iOS "popup" right?
Like derHugo says, check for internet connectivity is your best option
From what I can tell you have to create your custom plugin to achieve what Archero is doing.
At the end of the authentication process, iOS returns the viewController with the "login" form if the user is not authenticated.
On iOS the developer can decide to present this viewController or not. The social plugin doesn't have this option, they always present the login viewController if returned by the system... if you implement your plugin you could decide not to show it... ending up with what Archero is doing.

How to Close/Exit current instance of Xamarin.Forms app while loading a new one

We are facing a strange issue. Not sure if it is design flaw of the existing application. Your help/suggestion is appreciated.
We have a Xamarin.forms app. Targeted both for iOS and Android.
Problem is coming mainly in Android app.
Application flow:
once we logout from the application, app opens an logout activity and delete user info and other data.
opens a new activity for login which contains client SSO implementation
on successful login, app is setting user info and fetch data from web service.
then it calls LoadApplication method so that flow comes back in main application
Now if user perform logout/login several times, its opening a new application instance by calling LoadApplication method and then displaying home screen
So when user is tapping back button in home page, app is not closing and displays previous instance of same application.
User need to press back button several times (depending how many time user perform logout-login).
Is there any goodway to stop this?
Can we close current instance of the application before LoadApplication being called?
Stuck for a long time.
I'd try to avoid to call LoadApplication more then once. You should control the navigation stack.
Given you are on the LogoutPage
remove all views via PopToRootAsync
show the LoginPage
await Navigation.PopToRootAsync(false);
await Navigation.PushAsync(new LoginPage(), true);
This blog post may be worth a reading: https://jfarrell.net/2015/01/22/understanding-xamarin-forms-navigation/
Kindly try this.
https://stackoverflow.com/a/36885388/1941942
[Activity (NoHistory = true)]
public class LoginActivity : Activity { }
The saving instance error has gone a while after I implement it on MainActivity.

How can I test the background scan and launch the application in background with iBeacon-Android?

I am using the pro library.
But I just found doc for free library
I cannot find any doc for pro version.
Also, I don't know how to implement the background mode even using the pro sample.
Here are the steps:
Build the pro sample project
start the iBeacon source(using iPad) and it can be detected
start the application and then press home button the make it in
background
Turn off the iBeacon source
Turn on the iBeacon source
However, more than 5 minutes, the application does not launch
So, can anyone verify the step I did?
How can I test the background mode more easily?
Also, for the BootstrapNotifier, is it just work only first time when the device reboot?
After that, even I put application in background, the application will not launch when it detect iBeacon?
Your testing method sounds fine. I think the issue is that the reference app for the pro library only auto launches the app on the first detection after boot. After that, it sends a notification instead, and tapping on that notification launches the app.
This is purely for demonstration purposes. You can change it to auto launch on every detection if you wish. Simply alter the haveDetectedIBeaconsSinceBoot logic in this code:
#Override
public void didEnterRegion(Region arg0) {
// In this example, this class sends a notification to the user whenever an iBeacon
// matching a Region (defined above) are first seen.
Log.d(TAG, "did enter region.");
if (!haveDetectedIBeaconsSinceBoot) {
Log.d(TAG, "auto launching MainActivity");
// The very first time since boot that we detect an iBeacon, we launch the
// MainActivity
Intent intent = new Intent(this, MainActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
// Important: make sure to add android:launchMode="singleInstance" in the manifest
// to keep multiple copies of this activity from getting created if the user has
// already manually launched the app.
this.startActivity(intent);
haveDetectedIBeaconsSinceBoot = true;
} else {
// If we have already seen iBeacons and launched the MainActivity before, we simply
// send a notification to the user on subsequent detections.
Log.d(TAG, "Sending notification.");
sendNotification();
}
}
The javadoc link was missing from the main documentation page when you posted this question. That is fixed now.

Tombstoning listbox in WP7 application

I have a listbox in my WP7 app, and I would like to keep/save listbox inserted items when I reload the application. I tried this, but it not work:
protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
{
this.SaveState(e);
}
protected override void OnNavigatedTo(NavigationEventArgs e)
{
this.RestoreState();
}
What should I do??
In tombstoning you should look at storing application data in the PhoneApplicationService.State or IsolatedStorage.ApplicationSettings (depending on the size of the data).
The App.xaml.cs file already contains four methods to help you know when you application is 'Launching' (raised when the user initially launches the application), 'Activated' (raised when the application is dormant or tombstoned and the user navigates back to the application), 'Deactivated' (whenever the user navigates forward away from the application. Although applications are typically made dormant after they are deactivated, there is no way to know at this point whether the application will be tombstoned or terminated after this event) and 'Closing' (when the user uses the Back button to navigate backwards past the first page of your application. After this event, your application is terminated)
For more info check out : How to: Preserve and Restore Application State for Windows Phone

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