How to verify your app is installed from Play Store

Android provides a way to determine whether our app is installed via playstore or by any other appliaction. It would be very handy in case if we need to perform any action only when its a valid play store build and to ignore when its a debug build or a direct apk install from any apk sharing applications

 Android's PackageManager class helps us to identify the application that installed our app. Lets see how its done.

How To Read A File From Asset Folder In Android

Sometimes we might need to save few contents in a file and would try to access them in our android app. Say for example, you are working on an app and would like to mock your web service response, you can create a mock response (.json file) and place them in your Assets folder and access them.

The below code snippet can be used to read a file's content located at the asset folder in an android project. There is nothing fancy about it, it uses Java InputStream to read the file content and Android's Context to access file from Assets folder

Android Runtime Premission Example

     Every android app runs on its own sandbox. If in needs to access any recourse outside its sandbox, it should request permission from the system. There are few permissions that are automatically granted and there are few permissions that would require user to grant permission. Eg: location,contacts, sms etc.,

     All permissions that your app requires should be declared in the manifest file. Devices running Android 5.1(API level 22) and below, would request permission when the user installs the app and devices running Android 6 (API level 23) and above will request permissions when that app tries to use the resource which needs the permission i.e runtime permissions

So lets try a runtime permission sample program.

Step1: Create an android project with an Activity (PermissionActivity.java) and a layout file (activity_permission.xml)

Stept2: Now declare the required permission in the manifest file. This sample program would need SEND_SMS permission and your manifest file should look similar to the one below

Step3: Now lets design the screen with a TextView and a Button. The textview is used to display the current status of the permission and the button is used to request permission if not granted and if granted proceed with the functionality with the acquired permission

activity_permission.xml:

Step4: Now in the Activity, bind the UI components (TextView & Button). On click of the button request for SMS permission and proceed with the permission acquired.

PermissionActivity.java:

      On click of the button, we would check if the API version is 23 & above then we should check if the app has the permission or not using checkSelfPermission method. If not request the user for the permission at runtime using ActivityCompat.requestPermissions.

      During the permission request user may select Never ask again option and deny the permission. In such case, use the shouldShowRequestPremissionRationale which would be false, to determine whether to show an alternative explanation to user and direct him to setting menu or not.

      For all actions performed by the user in the runtime permission request dialog, we would receive a callback in the onRequestPermissionResult method.

Step5: Run the app in an emulator or device with Android API level 23 or above. Click on the Send SMS button. System would prompt a dialog requesting a runtime permission to send sms from you app.

Output:

How to check Network Connectivity Status in Android

In this post, we will see how to check the Network Connectivity Status in Android. Our app may have to behave differently based on the network it is connected i.e wifi,mobile,vpn etc., To check the network connectivity info, we use the ConnectivityManager and NetworkInfo class of android net package.

The below snippet demonstrates how to detect whether the mobile is connected to WIFI or Mobile data.

Code Snippet: