Application available on android

Android Application Class

W hile Starting App development, we tend to miss out simple basic stuffs either by ignorance or by curiosity to build million dollar app. But, Hey! Why so serious !. Building a App is bit of Art ,bit of Engineering and frequently both.

Activity Life Cycle is stages of activity in run time, knowing these would save you from headaches while you dive deeper in development.

I have written a post that will help you to understand activity lifecycle in a practical approach. Check it out

Android Activity Lifecycle

Android activity lifecycle is first thing to be known as android developer. Here I’m sharing with you some facts and…

Application class is a base class of Android app containing components like Activities and Services. Application or its sub classes are instantiated before all the activities or any other application objects have been created in Android app.

You Don’t have to import or extend application class, they are predefined. We cannot change application class but we could give additional instruction to it by extending it. Refer here for more info.

Create a java class named SubApplication and Application as Superclass

By extending Application class you could get boilerplate code like this

Check in AndroidManifest.xml and set Application name to SubApplication that you created

Lets take a situation where we should know which activity is currently running and we have to use register network receiver in all our activities. To this we used to write same code in all the activities or write a base class and extend that class instead of extending AppCompactActivity.

We have Activity Life cycle in one hand and Application class in another, what sense they make? Well actually they do? Let’s look into it.

1. In application class create static Activity variable it is accessible from whole project.

2. Register Activity Life Cycle callback in onCreate method in application class. By this step we can get currently running activity in our app from mActivity.

3.Moving on to next, Create a Broadcast Receiver and write a method to check the internet connection. you can get the code here .

4. Register your broadcast receiver in Manifest File

But for SDK Above Nougat we need to register receiver and unregister in every activity we use programmatically or We can just register and unregister Commonly in Application class.

5. Create a Object for Broadcast Receiver in application class and Register it in onResume method and Unregister in onPause method.

Bit confused! Don’t Worry, Here is the Link to the files.

Thanks for reading out the article. Let me know if I have missed out something interesting so that I can be added. Be sure to clap/recommend as much as you can and also share with your friends.

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Understanding the Android Application Class

The Application class in Android is the base class within an Android app that contains all other components such as activities and services. The Application class, or any subclass of the Application class, is instantiated before any other class when the process for your application/package is created.

This class is primarily used for initialization of global state before the first Activity is displayed. Note that custom Application objects should be used carefully and are often not needed at all.

In many apps, there’s no need to work with an application class directly. However, there are a few acceptable uses of a custom application class:

• Specialized tasks that need to run before the creation of your first activity
• Global initialization that needs to be shared across all components (crash reporting, persistence)
• Static methods for easy access to static immutable data such as a shared network client object

Note that you should never store mutable shared data inside the Application object since that data might disappear or become invalid at any time. Instead, store any mutable shared data using persistence strategies such as files, SharedPreferences or SQLite .

If we do want a custom application class, we start by creating a new class which extends android.app.Application as follows:

And specify the android:name property in the the node in AndroidManifest.xml :

That’s all you should need to get started with your custom application.

There is always data and information that is needed in many places within your app. This might be a session token, the result of an expensive computation, etc. It might be tempting to use the application instance in order to avoid the overhead of passing objects between activities or keeping those in persistent storage.

However, you should never store mutable instance data inside the Application object because if you assume that your data will stay there, your application will inevitably crash at some point with a NullPointerException . The application object is not guaranteed to stay in memory forever, it will get killed. Contrary to popular belief, the app won’t be restarted from scratch. Android will create a new Application object and start the activity where the user was before to give the illusion that the application was never killed in the first place.

So how should we store shared application data? We should store shared data in one of the following ways:

• Explicitly pass the data to the Activity through the intent.
• Use one of the many ways to persist the data to disk.

Bottom Line: Storing data in the Application object is error-prone and can crash your app. Prefer storing your global data on disk if it is really needed later or explicitly pass to your activity in the intent’s extras.

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Package visibility in Android 11

On Android 10 and earlier, apps could query the full list of installed apps on the system using methods like queryIntentActivities() . In most cases, this is far broader access than is necessary for an app to implement its functionality. With our ongoing focus on privacy, we’re introducing changes on how apps can query and interact with other installed apps on the same device on Android 11. In particular, we’re bringing better scoped access to the list of apps installed on a given device.

To provide better accountability for access to installed apps on a device, apps targeting Android 11 (API level 30) will see a filtered list of installed apps by default. In order to access a broader list of installed apps, an app can specify information about apps they need to query and interact with directly. This can be done by adding a element in the Android manifest.

For most common scenarios, including any implicit intents started with startActivity() , you won’t have to change anything! For other scenarios, like opening a specific third party application directly from your UI, developers will have to explicitly list the application package names or intent filter signatures like this:

If you use Custom Tabs to open URLs, you might be calling resolveActivity() and queryIntentActivities() in order to launch a non-browser app if one is available for the URL. In Android 11 there’s a better way to do this, which avoids the need to query other apps: the FLAG_ACTIVITY_REQUIRE_NON_BROWSER intent flag. When you call startActivity() with this flag, an ActivityNotFoundException will be thrown if a browser would have been launched. When this happens, you can open the URL in a Custom Tab instead.

In rare cases, your app might need to query or interact with all installed apps on a device, independent of the components they contain. To allow your app to see all other installed apps, Android 11 introduces the QUERY_ALL_PACKAGES permission. In an upcoming Google Play policy update, look for guidelines for apps that need the QUERY_ALL_PACKAGES permission.

When targeting API level 30 and adding a element to your app, use the latest available release of the Android Gradle plugin. Soon we’ll be releasing updates to older Android Gradle plugin versions to add support for this element. You can find more information and use cases about Package Visibility in the developer documentation.

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Implement In-app Update In Android

Make sure every user of your app is on the new version.

Apr 6, 2020 · 8 min read

In this article, we will learn about the In-app update feature in Android what is all about In-app update, what are the benefits of using the In-app update in your android application. Recently I’ve been working on a product in which I need to Implement an In-app update Why we need to Implement this?.

As a Developer we always want our users to have the updated version of their application but there are a lot of people who actually turned off their auto update from google play store and he/she doesn’t know about any update available or not.

To overcome the problem Google Introduced this feature called In-app update from this feature you can easily prompt the user to update the application and with the user permission you can update the application also while updating the app user can be able to interact with the application. Now the user doesn’t need to go to google play store to check there is any update available or not.

What is In-App Update:

An In-app update was Introduced as a part of the Play Core Library, which actually allows you to prompts the user to update the application when there is any update available on the Google Play Store.

There are two modes of an In-app update.

• Flexible Update
• Immediate Update

Flexible Update:

In Flexible update, the dialog will appear and after the update, the user can interact with the application.

This mode is recommended to use when there is no major change In your application like some features that don’t affect the core functionality of your application.

The update of the application is downloading in the background in the flexible update and after the completion of the downloading, the user will see the dialog in which the user needs to restart the application. The dialog will not automatically show, we need to check and show to the user and we will learn how later.

Benefits:

The major benefit of the flexible update is the user can interact with the application.

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Android Application Class

W hile Starting App development, we tend to miss out simple basic stuffs either by ignorance or by curiosity to build million dollar app. But, Hey! Why so serious !. Building a App is bit of Art ,bit of Engineering and frequently both.

Activity Life Cycle is stages of activity in run time, knowing these would save you from headaches while you dive deeper in development.

I have written a post that will help you to understand activity lifecycle in a practical approach. Check it out

Android Activity Lifecycle

Android activity lifecycle is first thing to be known as android developer. Here I’m sharing with you some facts and…

Application class is a base class of Android app containing components like Activities and Services. Application or its sub classes are instantiated before all the activities or any other application objects have been created in Android app.

You Don’t have to import or extend application class, they are predefined. We cannot change application class but we could give additional instruction to it by extending it. Refer here for more info.

Create a java class named SubApplication and Application as Superclass

By extending Application class you could get boilerplate code like this

Check in AndroidManifest.xml and set Application name to SubApplication that you created

Lets take a situation where we should know which activity is currently running and we have to use register network receiver in all our activities. To this we used to write same code in all the activities or write a base class and extend that class instead of extending AppCompactActivity.

We have Activity Life cycle in one hand and Application class in another, what sense they make? Well actually they do? Let’s look into it.

1. In application class create static Activity variable it is accessible from whole project.

2. Register Activity Life Cycle callback in onCreate method in application class. By this step we can get currently running activity in our app from mActivity.

3.Moving on to next, Create a Broadcast Receiver and write a method to check the internet connection. you can get the code here .

4. Register your broadcast receiver in Manifest File

But for SDK Above Nougat we need to register receiver and unregister in every activity we use programmatically or We can just register and unregister Commonly in Application class.

5. Create a Object for Broadcast Receiver in application class and Register it in onResume method and Unregister in onPause method.

Bit confused! Don’t Worry, Here is the Link to the files.

Thanks for reading out the article. Let me know if I have missed out something interesting so that I can be added. Be sure to clap/recommend as much as you can and also share with your friends.

Источник