Tutorial by Examples: e

The reason you do not have to override Awake, Start, Update and other method is because they are not virtual methods defined in a base class. The first time your script gets accessed, the scripting runtime looks through the script to see if some methods are defined. If they are, that information is...

Example method in controller @RequestMapping(value = "/test") public String showCheckbox(Model model) { boolean myBooleanVariable = false; model.addAttribute("myBooleanVariable", myBooleanVariable); return "sample-checkbox"; } View: sample-checkbox....

To forbid null values in your table columns, add the :null parameter to your migration, like this: class AddPriceToProducts < ActiveRecord::Migration def change add_column :products, :float, null: false end end

In order to have google maps work properly with turbolinks, add the javascript tag directly to the layout header rather than including it in a view. # app/views/layouts/my_layout.html.haml !!! %html{:lang => 'en'} %head - # ... = google_maps_api_script_tag The google_maps_api_s...

Suppose, your users and/or groups have profiles and you want to display address profile fields on a google map. # app/models/profile_fields/address.rb class ProfileFields::Address < ProfileFields::Base # Attributes: # label, e.g. "Work address" # value, e.g. "Willy-Bran...

On the profile view, show the profile fields of a user or group in a list as well as the address fields on a google map. - # app/views/profiles/show.html.haml %h1 Contact Information .profile_fields = render @profile_fields .google_map{data: address_fields: @address_fields.to_json } The ap...

Suppose, there is a .google_map div, which will become the map, and which has the address fields to show as markers as data attribute. For example: <!-- http://localhost:3000/profiles/123 --> <div class="google_map" data-address-fields="[ {label: 'Work address', value: ...

Provided an App.GoogleMap coffee script class, the google map can be initialized like this: # app/assets/javascripts/google_maps.js.coffee # ... class App.GoogleMap map_div: {} map: {} constructor: (map_div)-> @map_div = map_div @init_map() @reference_the_map_as_dat...

Provided an App.GoogleMap coffee script class and the marker information being stored in the data-address-fields attribute of the .google_map div, the map markers can be initialized on the map like this: # app/assets/javascripts/google_maps.js.coffee # ... class App.GoogleMap # ... markers:...

Provided an App.GoogleMap coffee script class with the google.maps.Map stored as @map and the google.maps.Markers stored as @markers, the map can be auto-zoomed, i.e. adjusted that all markers are visible, like this: on the map like this: # app/assets/javascripts/google_maps.js.coffee # ... cla...

To display address profile fields as markers on a google map, the address field objects need to be passed as json objects to javascript. Regular database attributes When calling to_json on an ApplicationRecord object, the database attributes are automatically exposed. Given a ProfileFields::Addre...

If you need to search an ActiveRecord model for similar values, you might be tempted to use LIKE or ILIKE but this isn't portable between database engines. Similarly, resorting to always downcasing or upcasing can create performance issues. You can use ActiveRecord's underlying Arel matches method...

NotificationCompat.Builder mBuilder = (NotificationCompat.Builder) new NotificationCompat.Builder(context) .setSmallIcon(R.drawable.some_small_icon) .setContentTitle("Title") .setContentText("This is a test notification with MAX priority")...

A has_many :through association is often used to set up a many-to-many connection with another model. This association indicates that the declaring model can be matched with zero or more instances of another model by proceeding through a third model. For example, consider a medical practice where p...

A has_one :through association sets up a one-to-one connection with another model. This association indicates that the declaring model can be matched with one instance of another model by proceeding through a third model. For example, if each supplier has one account, and each account is associated...

A has_and_belongs_to_many association creates a direct many-to-many connection with another model, with no intervening model. For example, if your application includes assemblies and parts, with each assembly having many parts and each part appearing in many assemblies, you could declare the models...

Picasso.with(context) .load(uri) .networkPolicy(NetworkPolicy.NO_CACHE) .memoryPolicy(MemoryPolicy.NO_CACHE) .placeholder(R.drawable.placeholder) .into(imageView);

Sometimes it can be useful to set your application locale based upon the request IP. You can easily achieve this using Geocoder. Among the many things Geocoder does, it can also tell the location of a request. First, add Geocoder to your Gemfile # Gemfile gem 'geocoder' Geocoder adds location...

We can check the status of migrations by running 3.05.0 rake db:migrate:status 5.0 rails db:migrate:status The output will look like this: Status Migration ID Migration Name -------------------------------------------------- up 20140711185212 Create documentation pages up ...

Rails have very easy way to get first and last record from database. To get the first record from users table we need to type following command: User.first It will generate following sql query: SELECT `users`.* FROM `users` ORDER BY `users`.`id` ASC LIMIT 1 And will return following recor...