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Use JSONBuddy as your JSON editor for the Windows platform to create and modify JSON content or JSON Schema files and get access to extraordinary editor features like JSON well-formed checking, intelligent auto-completion, pretty-print, remove whitespace and JSON validation. Application list all JSON files present on phone. We can use this application to Create, Edit, Download, Validate and Share(text) JSON files.APP IS BEING. JSON Parsing File Example 2 In Android Studio: Below is the 2nd example of JSON parsing In Android Studio. In this example we create a JSON file and store it in assets folder of Android. In this JSON file we have list of users where each object contain the information like user id, name, email, gender and different contact numbers.
- Apr 06, 2019 A JSON File is one developed to store simple data objects and structures in the format of JavaScript Notation shortened as JSON. JSON is a standard data interchange format. The file can be used in transmitting data between a server and a web application. Some of the unique features that make Json File special are.continue reading 'Open JSON File'.
- I want to know where should i place the json file in my project and how to read and store it. Reading a json file in Android closed. Download a file with.
After you build your Android App Bundle, you should test how Google Playuses it to generate APKs and how those APKs behave when deployed to a device.There are two ways you should consider testing your app bundle: locally using the
bundletool
command line tool and through Google Play byuploading your bundle to the Play Consoleand using a test track. This page explains how to use bundletool
to test yourapp bundle locally.bundletool
is the underlying tool that Gradle, Android Studio, and GooglePlay use to build an Android App Bundle or convert an app bundle into thevarious APKs that are deployed to devices. bundletool
is also available toyou as a command line tool, so you can recreate, inspect, and verify GooglePlay’s server-side build of your app’s APKs.You should use Android Studio and the Android plugin for Gradle tobuild and sign an Android App Bundle.However, if using the IDE is not an option (for example, because you’re using a continuousbuild server), you can alsobuild your app bundle from the command lineand sign it using
Note: You can not use jarsigner
.apksigner
to sign your app bundle.By default, the IDE does not use app bundles to deploy your app to a localdevice for testing. However, you canmodify your run/debug configurationand select the option to deploy APK from app bundle to see how it affectsyour app's execution.
Download bundletool
If you haven't already done so, download
bundletool
from theGitHub repository.Generate a set of APKs from your app bundle
When
bundletool
generates APKs from your app bundle, it includes them in acontainer called an APK set archive, which uses the .apks
fileextension. To generate an APK set for all device configurations your appsupports from your app bundle, use the bundletool build-apks
command, asshown below.If you want to deploy the APKs to a device, you need to also include your app’ssigning information, as shown in the command below. If you do not specifysigning information,
bundletool
attempts to sign your APKs with a debug keyfor you.The table below describes the various flags and options you can set when usingthe
bundletool build-apks
command in greater detail. Only--bundle
and --output
are required—all other flags are optional.Flag | Description |
---|---|
--bundle=path | (Required) Specifies the path to the app bundle you built using Android Studio. To learn more, read Build your project. |
--output=path | (Required) Specifies the name of the output `.apks` file, which contains all the APK artifacts for your app. To test the artifacts in this file on a device, go to the section about how to deploy APKs to a connected device. |
--overwrite | Include this flag if you want to overwrite any existing output file with the same path you specify using the --output option. If you don't include this flag and the output file already exists, you get a build error. |
--aapt2=path | Specifies a custom path to AAPT2. By default, bundletool includes its own version of AAPT2. |
--ks=path | Specifies the path to the deployment keystore used to sign the APKs. This flag is optional. If you don't include it, bundletool attempts to sign your APKs with a debug signing key. |
--ks-pass=pass:password or --ks-pass=file:/path/to/file | Specifies your keystore’s password. If you’re specifying a password in plain text, qualify it with pass: . If you’re passing the path to a file that contains the password, qualify it with file: . If you specify a keystore using the --ks flag without specifying --ks-pass , bundletool prompts you for a password from the command line. |
--ks-key-alias=alias | Specifies the alias of the signing key you want to use. |
--key-pass=pass:password or --key-pass=file:/path/to/file | Specifies the password for the signing key. If you’re specifying a password in plain text, qualify it with pass: . If you’re passing the path to a file that contains the password, qualify it with file: . If this password is identical to the one for the keystore itself, you can omit this flag. |
--connected-device | Instructs bundletool to build APKs that target the configuration of a connected device. If you don’t include this flag, bundletool generates APKs for all device configurations your app supports. |
--device-id=serial-number | If you have more than one connected device, use this flag to specify the serial ID of the device to which you want to deploy your app. |
--device-spec=spec_json | Use this flag to provide a path to a .json file that specifies the device configuration you want to target. To learn more, go to the section about how to Create and use device specification JSON files. |
--mode=universal | Set the mode to universal if you want bundletool to build only a single APK that includes all of your app's code and resources such that the APK is compatible with all device configurations your app supports. Note: bundletool includes only dynamic feature modules that specify <dist:fusing dist:include='true'/> in their manifest in a universal APK. To learn more, read about the Dynamic feature module manifest. Keep in mind, these APKs are larger than those optimized for a particular device configuration. However, they’re easier to share with internal testers who, for example, want to test your app on multiple device configurations. |
Deploy APKs to a connected device
After you generate a set of APKs,
bundletool
can deploy the rightcombination of APKs from that set to a connected device.For example, if you have a connected device running Android 5.0 (API level 21)or higher,
bundletool
pushes the base APK, dynamic feature APKs, andconfiguration APKs required to run your app on that device. Alternatively, ifyour connected device is running Android 4.4 (API level 20) or lower,bundletool
looks for a compatible multi-APK and deploys it to your device.To deploy your app from an APK set, use the
install-apks
command and specifythe path of the APK set using the--apks=/path/to/apks
flag, asshown below. (If you have multiple devices connected, specify a target deviceby adding the --device-id=serial-id
flag.)Generate a device-specific set of APKs
If you’d rather not build a set of APKs for all device configurations your appsupports, you can build APKs that target only the configuration of a connecteddevice using the
--connected-device
option, as shown below. (If you havemultiple devices connected, specify a target device by including the--device-id=serial-id
flag.)Generate and use device specification JSON files
bundletool
is capable of generating an APK set that targets a deviceconfiguration specified by a JSON file. To first generate a JSON file for aconnected device, run the following command:bundletool
creates a JSON file for your device in the directory the tool islocated. You can then pass it to bundletool
to generate a set of APKs thattarget only the configuration described in that JSON file as follows:Manually create a device specification JSON
If you don’t have access to the device for which you want to build a targetedAPK set (for example, a friend wants to try your app with a device you don’thave on-hand), you can manually create a JSON file using the following format:
You can then pass this JSON to the
bundle extract-apks
command, as describedin the previous section.Extract device-specific APKs from an existing APK set
If you have an existing APK set and you want to extract from it a subset of APKsthat target a specific device configuration, you can use the
extract-apks
command and specify a device specification JSON, as follows:Measure the estimated download sizes of APKs in an APK set
To measure the estimated download sizes of APKs in an APK set as they wouldbe served compressed over-the-wire, use the
get-size total
command:You can modify the behavior of the
get-size total
command using thefollowing flags:Flag | Description |
---|---|
--apks=path | (Required) Specifies the path to the existing APK set file whose download size is measured. |
--device-spec=path | Specifies the path to the device spec file (from get-device-spec or constructed manually) to use for matching. You can specify a partial path to evaluate a set of configurations. |
--dimensions=dimensions | Specifies the dimensions used when computing the size estimates. Accepts a comma-separated list of: SDK , ABI , SCREEN_DENSITY , and LANGUAGE . To measure across all dimensions, specify ALL . |
--instant | Measures the download size of the instant-enabled APKs instead of the installable APKs. By default, bundletool measures the installable APK download sizes. |
--modules=modules | Specifies a comma-separated list of modules in the APK set to consider in the measurement. The bundletool command automatically includes any dependent modules for the specified set. By default, the command measures the download size of all modules installed during the first download. |
Additional resources
To learn more about using
bundletool
, try the following resource.Codelabs
- Your First Android App Bundle,a codelab that explores the basic principles of Android App Bundles and showsyou how to quickly get started with building your own using Android Studio.This codelab also explores how to test your app bundlesusing
bundletool
.
- Android Basics
- Android - User Interface
- Android Advanced Concepts
- Android Useful Examples
- Android Useful Resources
- Selected Reading
JSON stands for JavaScript Object Notation.It is an independent data exchange format and is the best alternative for XML. This chapter explains how to parse the JSON file and extract necessary information from it.
Android provides four different classes to manipulate JSON data. These classes are JSONArray,JSONObject,JSONStringer and JSONTokenizer.
The first step is to identify the fields in the JSON data in which you are interested in. For example. In the JSON given below we interested in getting temperature only.
JSON - Elements
An JSON file consist of many components. Here is the table defining the components of an JSON file and their description −
Sr.No | Component & description |
---|---|
1 | Array([) In a JSON file , square bracket ([) represents a JSON array |
2 | Objects({) In a JSON file, curly bracket ({) represents a JSON object |
3 | Key A JSON object contains a key that is just a string. Pairs of key/value make up a JSON object |
4 | Value Each key has a value that could be string , integer or double e.t.c |
JSON - Parsing
For parsing a JSON object, we will create an object of class JSONObject and specify a string containing JSON data to it. Its syntax is −
The last step is to parse the JSON. A JSON file consist of different object with different key/value pair e.t.c. So JSONObject has a separate function for parsing each of the component of JSON file. Its syntax is given below −
The method getJSONObject returns the JSON object. The method getString returns the string value of the specified key.
Apart from the these methods , there are other methods provided by this class for better parsing JSON files. These methods are listed below −
Sr.No | Method & description |
---|---|
1 | get(String name) This method just Returns the value but in the form of Object type |
2 | getBoolean(String name) This method returns the boolean value specified by the key |
3 | getDouble(String name) This method returns the double value specified by the key |
4 | getInt(String name) This method returns the integer value specified by the key |
5 | getLong(String name) This method returns the long value specified by the key |
6 | length() This method returns the number of name/value mappings in this object.. |
7 | names() This method returns an array containing the string names in this object. |
Example
To experiment with this example , you can run this on an actual device or in an emulator.
Steps | Description |
---|---|
1 | You will use Android studio to create an Android application. |
2 | Modify src/MainActivity.java file to add necessary code. |
3 | Modify the res/layout/activity_main to add respective XML components |
4 | Modify the res/values/string.xml to add necessary string components |
5 | Run the application and choose a running android device and install the application on it and verify the results |
Json File Download For Android Phone
Following is the content of the modified main activity file src/MainActivity.java.
Following is the modified content of the xml HttpHandler.java.
Following is the modified content of the xml res/layout/activity_main.xml.
Following is the modified content of the xml res/layout/list_item.xml.
Following is the content of AndroidManifest.xml file.
Json File Download For Android Phone
Let's try to run our application we just modified. I assume you had created your AVD while doing environment setup. To run the app from Android studio, open one of your project's activity files and click Run icon from the toolbar. Android studio installs the app on your AVD and starts it and if everything is fine with your setup and application, it will display following Emulator window −
Above Example showing the data from string json,The data has contained employer details as well as salary information.