NeatForm lets you generate android views using JSON schema. This is especially useful when you are trying things out or when you need to update the UI without necessarily having to rebuild the app. NeatForm comes in handy when authoring forms with repetative UI designs but different configurations especially data collection forms. The idea behind this project was birthed out of frustration in working on such projects. The library will be shipped with common views used for data collection comprising of multiple question checkboxes, single question radio buttons, input text fields etc. In addition, ability to specify rules to handle skip logic and calculations on the form (All these done via JSON for the UI and JSON/YML for the Rules Engine as supported by Easy Rules). NeatForm does not aim at replacing Android view creation using XML.
Read the full documentation on the wiki
Add the library as a dependency to your app's build.gradle file
dependencies {
//....
implementation "com.nerdstone:neat-form-core:1.1.5"
//....
} This library is also available as a git package Neat Form Packages.
At the moment GitHub requires you to be authenticated in order to download Android Libraries hosted in GitHub packages. To do so you will need your personal access token and your GitHub userid/username. Follow these steps to add the library as a dependency to your app.
Step 1 : Generate a Personal Access Token for GitHub How to generate GitHub personal access token
Step 2 : Store your GitHub — Personal Access Token details
Add these content to the local.properties file inside the root directory of your project.
gpr.usr=YOUR_GITHUB_USERID
gpr.key=YOUR_PERSONAL_ACCESS_TOKEN
Step 3 : Update build.gradle for the application module
def githubProperties = new Properties()
//Read the github properties content
githubProperties.load(new FileInputStream(rootProject.file("local.properties")))
android {
//...
// include inside the android closure
repositories {
maven {
name = "GitHubPackages"
/**
* Configure path of the package repository on Github using the GITHUB_USER_ID and * Git Repository */
url = uri("https://maven.pkg.github.com/ellykits/neat-form")
credentials {
/** get credentials from local.properties in root project folder file with
** gpr.usr=GITHUB_USER_ID & gpr.key=PERSONAL_ACCESS_TOKEN otherwise ** Set env variable GPR_USER & GPR_API_KEY**/
username = githubProperties['gpr.usr'] ?: System.getenv("GPR_USER")
password = githubProperties['gpr.key'] ?: System.getenv("GPR_API_KEY")
}
} } //...
}
Add the library in the dependency section of your application's build.gradle file (obtain the latest version from Neat Form Packages)
dependencies {
//consume library - use the latest version available on github packages
implementation "com.nerdstone:neat-form-core:1.1.5"
//....
} These instructions will help you get started in setting up your forms and running the app.
Expect implementation of many views with the upcoming updates as work on this is still ongoing
First you will need to add the form file with its corresponding rules file to the assets directory of your application. Here are the supported attributes for the form.
| Form Attribute | Usage |
|---|---|
| form | Name of your form |
| rules_file | File containing the rules for handling skip logic and calculation |
| steps | The form steps with the desired fields |
| metadata | Additional information that you would also like to pass with the form when submitting data |
Sample form obtained from the sample app on this lib
{
"form":"Profile",
"rules_file":"rules/yml/sample_one_form_rules.yml",
"steps":[
{
"title":"Demographics",
"fields":[
{
"name":"adult",
"type":"text_input_edit_text",
"properties":{
"hint":"Enter adult's phone number",
"type":"name",
"padding":"8"
},
"meta_data":{
"openmrs_entity":"",
"openmrs_entity_id":"",
"openmrs_entity_parent":""
},
"validation":[
{
"condition":"value.length() <= 10",
"message":"value should be less than or equal to ten digits"
}
],
"subjects":"age:number, child:text",
"required_status":"Yes:please add phone number"
},
{
"name":"age",
"type":"text_input_edit_text",
"properties":{
"hint":"Enter your age",
"type":"name",
"padding":"8"
},
"meta_data":{
"openmrs_entity":"",
"openmrs_entity_id":"",
"openmrs_entity_parent":""
},
"validation":[
{
"condition":"value.matches(\"^\\\\d{1,2}?$\")",
"message":"Not a valid age"
}
],
"required_status":"yes:Please add age"
},
{
"name":"child",
"type":"text_input_edit_text",
"properties":{
"hint":"I am a child",
"type":"name",
"padding":"8"
},
"meta_data":{
"openmrs_entity":"",
"openmrs_entity_id":"",
"openmrs_entity_parent":""
},
"required_status":"yes:Please add age",
"subjects":"age:number"
},
{
"name":"email_subscription",
"type":"checkbox",
"properties":{
"text":"Subscribe to email notifications"
},
"required_status":"yes:Please specify if you want subscription",
"subjects":"age:number"
},
{
"name":"gender",
"type":"spinner",
"properties":{
"text":"Choose your gender"
},
"options":[
{
"name":"female",
"text":"Female",
"meta_data":{
"openmrs_entity":"",
"openmrs_entity_id":"A123390123123",
"openmrs_entity_parent":""
}
},
{
"name":"male",
"text":"Male",
"meta_data":{
"openmrs_entity":"",
"openmrs_entity_id":"S8918313",
"openmrs_entity_parent":""
}
}
],
"subjects":"email_subscription:map",
"required_status":"yes:Please specify your gender"
},
{
"name":"country",
"type":"spinner",
"properties":{
"text":"Choose your country of Origin",
"searchable":"Search country"
},
"options":[
{
"name":"none",
"text":"Select country"
},
{
"name":"america",
"text":"United States Of America",
"meta_data":{
"country_code":"+1"
}
},
{
"name":"canada",
"text":"Canada",
"meta_data":{
"country_code":"+1"
}
},
{
"name":"uk",
"text":"United Kingdom",
"meta_data":{
"country_code":"+44"
}
},
{
"name":"australia",
"text":"Australia",
"meta_data":{
"country_code":"+61"
}
},
{
"name":"Kenya",
"text":"Kenya",
"meta_data":{
"country_code":"+254"
}
},
{
"name":"tanzania",
"text":"Tanzania",
"meta_data":{
"country_code":"+255"
}
},
{
"name":"china",
"text":"China",
"meta_data":{
"country_code":"+86"
}
},
{
"name":"sweden",
"text":"Sweden",
"meta_data":{
"country_code":"+1"
}
},
{
"name":"russia",
"text":"Russia",
"meta_data":{
"country_code":"+7"
}
},
{
"name":"japan",
"text":"Japan",
"meta_data":{
"country_code":"+81"
}
},
{
"name":"singapore",
"text":"Singapore",
"meta_data":{
"country_code":"+65"
}
}
],
"subjects":"email_subscription:map",
"required_status":"yes:Please specify your country"
},
{
"name":"choose_language",
"type":"multi_choice_checkbox",
"properties":{
"text":"Pick the languages you are proficient in."
},
"options":[
{
"name":"eng",
"text":"English",
"meta_data":{
"openmrs_entity":"",
"openmrs_entity_id":"A123123123123",
"openmrs_entity_parent":""
}
},
{
"name":"french",
"text":"French",
"meta_data":{
"openmrs_entity":"",
"openmrs_entity_id":"A123123123123",
"openmrs_entity_parent":""
}
},
{
"name":"kisw",
"text":"Kiswahili",
"meta_data":{
"openmrs_entity":"",
"openmrs_entity_id":"A123123123123",
"openmrs_entity_parent":""
}
},
{
"name":"need_help",
"text":"Help me choose",
"is_exclusive":true,
"meta_data":{
"openmrs_entity":"",
"openmrs_entity_id":"A918928912",
"openmrs_entity_parent":""
}
},
{
"name":"none",
"text":"None of the above",
"is_exclusive":true,
"meta_data":{
"openmrs_entity":"",
"openmrs_entity_id":"A123123123123",
"openmrs_entity_parent":""
}
}
],
"validation":[
{
"condition":" value != null && value['need_help'] == null",
"message":"You should be speaking at least one of the languages man!"
}
],
"required_status":"yes:Please specify your languages",
"subjects":"email_subscription:map, gender:text"
},
{
"name":"language_none",
"type":"edit_text",
"properties":{
"hint":"Specify your language",
"type":"name"
},
"meta_data":{
"openmrs_entity":"",
"openmrs_entity_id":"",
"openmrs_entity_parent":""
},
"required_status":"true:Please specify language",
"subjects":"choose_language:map"
},
{
"name":"wiki_contribution",
"type":"radio_group",
"properties":{
"text":"Have you ever contributed to or written a page in the Wiki?"
},
"options":[
{
"name":"yes",
"text":"Yes"
},
{
"name":"no",
"text":"No"
},
{
"name":"dont_know",
"text":"Dont know"
}
],
"validation":[
{
"condition":"value != null && !value.containsKey('dont_know')",
"message":"Don't know is not an option"
}
],
"required_status":"yes:Wiki contribution field is required.",
"subjects":"email_subscription:map"
},
{
"name":"wiki_contribution_yes",
"type":"edit_text",
"properties":{
"hint":"What was your contribution?",
"type":"name"
},
"validation":[
{
"condition":"value.startsWith('I')",
"message":"Your statement must start with I"
}
],
"required_status":"true:Please specify your contributions",
"subjects":"wiki_contribution:map"
},
{
"name":"dob",
"type":"datetime_picker",
"properties":{
"hint":"Enter birth date",
"type":"date_picker",
"display_format":"dd/MM/yyyy"
},
"required_status":"true:Please specify your dob"
},
{
"name":"time",
"type":"datetime_picker",
"properties":{
"hint":"Enter time you clocked in",
"type":"time_picker",
"display_format":"hh:mm a"
},
"required_status":"true:Please specify the time you clocked in"
},
{
"name":"no_prev_pregnancies",
"type":"number_selector",
"properties":{
"visible_numbers":"5",
"max_value":"10",
"first_number":"0",
"text":"Number of previous pregnancies"
},
"validation":[
{
"condition":"value < 4",
"message":"Advice woman to register for Family Planning"
}
],
"subjects":"email_subscription:map",
"required_status":"yes:Please number of previous pregnancy"
},
{
"name":"delivery_methods",
"type":"multi_choice_checkbox",
"properties":{
"text":"Previous delivery methods."
},
"options":[
{
"name":"vaginal",
"text":"Vaginal delivery",
"meta_data":{
"openmrs_entity":"",
"openmrs_entity_id":"A12312332123123",
"openmrs_entity_parent":""
}
},
{
"name":"c-section",
"text":"C-Section",
"meta_data":{
"openmrs_entity":"",
"openmrs_entity_id":"A12123123123123",
"openmrs_entity_parent":""
}
}
],
"subjects":"no_prev_pregnancies:number"
}
]
}
]
} Neat form uses Easy Rules - Rules Engine library for handling form skip logic (logic for determining which widget should be shown/displayed on the form depending on the given condition). It is also used to perform form calculations.
Easy Rules provides support for defining rules with MVEL . You can use either JSON or YAML specification. More about the expression language support Easy Rules expression language support
Sample Rules file defined using YML specification.
---
name: "child_visibility"
description: "children are not allowed to buy alcohol"
priority: 1
condition: "age <= 18"
actions:
- "child_visibility = true"
---
name: "adult_calculation"
description: "decade calculation"
priority: 1
condition: "true"
actions:
- "import java.math.BigInteger;"
- "adult_calculation = age * 10"
---
name: "adult_visibility"
description: "adults can buy alcohol"
priority: 1
condition: "age > 18 || child == 'adult'"
actions:
- "adult_visibility = true"
---
name: "email_subscription_visibility"
description: "Display email subscription checkbox"
priority: 1
condition: "age > 18"
actions:
- "email_subscription_visibility = true"
---
name: "language_none_visibility"
description: "Specify language if none is chosen"
priority: 1
condition: "choose_language['none'] != null"
actions:
- "language_none_visibility = true"
---
name: "choose_language_visibility"
description: "Ask the user the languages they are proficient in"
priority: 1
condition: "gender.value == 'Female'"
actions:
- "choose_language_visibility = true"
---
name: "gender_visibility"
description: "Ask gender"
priority: 1
condition: "email_subscription != null"
actions:
- "gender_visibility = true"
---
name: "country_visibility"
description: "Ask country"
priority: 1
condition: "email_subscription != null"
actions:
- "country_visibility = true"
---
name: "no_prev_pregnancies_visibility"
description: "Ask last pregnancies"
priority: 1
condition: "email_subscription != null"
actions:
- "no_prev_pregnancies_visibility = true"
---
name: "wiki_contribution_yes_visibility"
description: "Ask contribution"
priority: 1
condition: "wiki_contribution != null && wiki_contribution.containsKey('yes')"
actions:
- "wiki_contribution_yes_visibility = true"
---
name: "wiki_contribution_visibility"
description: "Wiki contribution"
priority: 1
condition: "email_subscription != null"
actions:
- "wiki_contribution_visibility = true"
---
name: "delivery_methods_visibility"
description: "Delivery method"
priority: 1
condition: "no_prev_pregnancies > 0"
actions:
- "delivery_methods_visibility = true" At the moment form
JSONand rules are placed in assets directory. In future will provide a means of persisting the forms in a place where the can be easily updated.
Neat Form parses the JSON form provided from the Android Assets directory into a model that it uses to render the views. The supported views are registered first before the form is built. Once the views have been created as children to the the RootView they are then passed to the FormBuilder.
You can override the supported views with your own implementation(s) if the features provided out of the box by neat form do not suffice. However one thing to note is that you can only extend the classes that implement ViewBuilder but not the NFormView classes.
The views are rendered in 2 ways.
- Using the default vertical
LinearLayout- Views are rendered as per the order they are defined on theJSONform on on top of the other. (Suitable for low resolution devices; phones) - Using custom layout - Alternatively you may still want to control of the way the UI should appear across various devices for instances tablets, Neat Form gives you the flexibility of doing this by passing a list of the
xmllayout files to use when rendering the views.
NOTE: For multi-step forms, the form will be rendered to the custom layout sequentially i.e. step one form will be rendered on the layout at position 0 of the views list and so on.
Code snippet from the sample app's com.nerdstone.neatform.form.FormActivity
package com.nerdstone.neatform.form
import android.os.Bundle
import android.support.v7.app.AppCompatActivity
import android.view.View
import android.widget.ImageView
import android.widget.LinearLayout
import android.widget.TextView
import com.nerdstone.neatform.R
import com.nerdstone.neatformcore.domain.builders.FormBuilder
import com.nerdstone.neatformcore.form.json.JsonFormBuilder
import com.nerdstone.neatformcore.form.json.JsonFormEmbedded
class FormActivity : AppCompatActivity() {
private lateinit var mainLayout: LinearLayout
private lateinit var pageTitleTextView: TextView
private lateinit var exitFormImageView: ImageView
private var formBuilder: FormBuilder? = null
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.form_activity)
mainLayout = findViewById(R.id.mainLayout)
pageTitleTextView = findViewById(R.id.pageTitleTextView)
exitFormImageView = findViewById(R.id.exitFormImageView)
if (intent.extras != null) {
val path = intent?.extras?.getString("path") ?: ""
val pageTitle = intent?.extras?.getString("page")?.capitalizeWords()
pageTitleTextView.text = pageTitle
exitFormImageView.setOnClickListener {
if (it.id == R.id.exitFormImageView) {
finish()
}
}
//Create an embbeded JSON Form within mainLayout
formBuilder = JsonFormBuilder(this, formData.filePath)
JsonFormEmbedded(formBuilder as JsonFormBuilder, mainLayout).buildForm()
}
}
} Neat form uses Rules Engine to perform validations. The validation functionalities are wrapped inside NeatFormValidator. Each widget has a property referred to as formValidator that accepts a singleton instance of the validator class. Every widget is tasked with validating their own data via the overridden validateValue method. The validator class provides common functionality for validating fields through validateLabeledField and validateField methods; with the former used to validate widgets with top labels like MultiChoiceCheckbox and RadioGroupView, the later is used to validate the rest of the fields.
To validate a field add this to its JSON definition:
"validation": [
{
"condition": "value < 4",
"message": "Advice woman to register for Family Planning"
}
] The condition is evaluated and validation result returns true when the field is valid, false otherwise. The message attribute holds the error message displayed on the view when a field is invalid.
NOTE: value is a special kind of keyword in Neat form used to refer to the value of the current field. You can use the name of the field instead. With this approach you can potentially perform validation against other fields as well. Like in the case of password confirmation.
Neat form supports internationalization for the forms allowing localization for your app. For this you need to create a .properties file with the key-value entries for the translations. The convention is to give the properties file the same name as the json form file.
For example, if you have json form called collect_demographics.json create a file collect_demographics_en.properties in the /assets/resources/ folder for the english translations.
collect_demographics.json
{
"name": "gender",
"type": "spinner",
"properties": {
"text": "{{gender.properties.text}}"
},
"options": [
{
"name": "male",
"text": "{{gender.options.male}}",
"meta_data": {
...
}
},
{
"name": "female",
"text": "{{gender.options.female}}",
"meta_data": {
...
}
},
...
The translation string keys must be unique per file, they could however be anything the user wants. For convention and ease of maintainability it is recommended to use the Json Path notation. In the example below, the key for the translated text string under the properties field of the gender form field would be gender.properties.text.
For arrays e.g. options field the json path could altered to include the options key (instead of index) e.g. gender.options.male
collect_demographics.properties - (this is the file with the default language translations)
gender.properties.text = Your Gender
gender.options.male = Male
gender.options.female = Female
collect_demographics_fr.properties - (French language translations)
gender.properties.text = Votre sexe
gender.options.male = Mâle
gender.options.female = Femelle
The implementation uses Android's resource bundles so translations can be provided for all variations supported by Android. This includes specifying language, script, country and variant. See the android documentation Resource Bundle and Locale for more on locales and valid language codes.
NB: In this Multi-Language Support implementation, the localization respects the device language settings
Please check out the sample app for this demo.
App rendered using the default RootView (LinearLayout) and custom layout respectively.
Custom sample_one_form_custom_layout.xml layout used for rendering views
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:id="@+id/layout_age"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent">
<com.nerdstone.neatformcore.views.widgets.TextInputEditTextNFormView
android:id="@+id/age"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:layout_weight="1">
<android.support.design.widget.TextInputEditText
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</com.nerdstone.neatformcore.views.widgets.TextInputEditTextNFormView>
<com.nerdstone.neatformcore.views.widgets.TextInputEditTextNFormView
android:id="@+id/child"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_marginTop="16dp"
android:layout_weight="1"
android:visibility="gone">
<android.support.design.widget.TextInputEditText
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</com.nerdstone.neatformcore.views.widgets.TextInputEditTextNFormView>
<com.nerdstone.neatformcore.views.widgets.TextInputEditTextNFormView
android:id="@+id/adult"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_marginTop="16dp"
android:layout_weight="1"
android:visibility="gone">
<android.support.design.widget.TextInputEditText
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</com.nerdstone.neatformcore.views.widgets.TextInputEditTextNFormView>
</LinearLayout>
<com.nerdstone.neatformcore.views.widgets.CheckBoxNFormView
android:id="@+id/email_subscription"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintStart_toStartOf="@+id/layout_age"
app:layout_constraintTop_toBottomOf="@+id/layout_age" />
<com.nerdstone.neatformcore.views.widgets.SpinnerNFormView
android:id="@+id/gender"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
app:layout_constraintStart_toStartOf="@+id/email_subscription"
app:layout_constraintTop_toBottomOf="@+id/email_subscription" />
<com.nerdstone.neatformcore.views.containers.MultiChoiceCheckBox
android:id="@+id/choose_language"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
app:layout_constraintStart_toStartOf="@+id/gender"
app:layout_constraintTop_toBottomOf="@+id/gender" />
<com.nerdstone.neatformcore.views.widgets.EditTextNFormView
android:id="@+id/language_none"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
app:layout_constraintStart_toStartOf="@+id/gender"
app:layout_constraintTop_toBottomOf="@+id/choose_language" />
<com.nerdstone.neatformcore.views.containers.RadioGroupView
android:id="@+id/wiki_contribution"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
app:layout_constraintStart_toStartOf="@+id/gender"
app:layout_constraintTop_toBottomOf="@+id/language_none" />
<com.nerdstone.neatformcore.views.widgets.EditTextNFormView
android:id="@+id/wiki_contribution_yes"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
app:layout_constraintStart_toStartOf="@+id/gender"
app:layout_constraintTop_toBottomOf="@+id/wiki_contribution" />
<LinearLayout
android:orientation="horizontal"
android:id="@+id/date_time_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintStart_toStartOf="@+id/gender"
app:layout_constraintTop_toBottomOf="@+id/wiki_contribution_yes">
<com.nerdstone.neatformcore.views.widgets.DateTimePickerNFormView
android:id="@+id/dob"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="wrap_content"
android:layout_marginTop="16dp" />
<com.nerdstone.neatformcore.views.widgets.DateTimePickerNFormView
android:id="@+id/time"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:layout_marginLeft="16dp"/>
</LinearLayout>
<com.nerdstone.neatformcore.views.widgets.NumberSelectorNFormView
android:id="@+id/no_prev_pregnancies"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
app:layout_constraintStart_toStartOf="@+id/gender"
app:layout_constraintTop_toBottomOf="@+id/date_time_layout" />
<com.nerdstone.neatformcore.views.containers.MultiChoiceCheckBox
android:id="@+id/delivery_methods"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
app:layout_constraintStart_toStartOf="@+id/gender"
app:layout_constraintTop_toBottomOf="@+id/no_prev_pregnancies" />
</android.support.constraint.ConstraintLayout>
- The id of the views MUST match the name attribute of the fields in the
JSONfor custom view rendering to work.- Another thing to note is the use of NeatForm Custom
Viewson theXMLlayout file.- Using custom layout give you the flexibility of styling and arranging your views the way you want them to be. Allowing the use of other view attributes not supported by the library.
JSONform attributes takes precedence over theXMLattributes if same attributes are defined on theJSONform and on theXML
- Easy Rules - Rules Engine library
- Mockk - Testing Framework Kotlin
- GSON - Parsing JSON files
- Smart Material Spinner - Powerful android spinner library
| Status | Action |
|---|---|
| ✔️ | ️ Implementation of the common views - multichoice checkbox, spinner, buttons, radio buttons number selector |
| ✔️ | ️ Data management - saving data from the input fields |
| ✔️ | ️ Form Fields Validation |
| ✔️ | ️ Support Multi-Step Forms |
| ✔️ | ️ Rules Engine integration - handle form skip logic and calculations |
| ✔️ | ️ Multi language support - Internationalization (i18n) |
| ❌ | ️ Support image and location picker and barcode reader |
| ❌ | ️ Ability to obtain and render JSONform from server |
If you need addition of more attributes on the current widgets or new widget implementations, create an issue. Contributions are also welcome.
This project is licensed under the Apache 2.0 License - see the LICENSE file for details