How to implement applications for Smart Devices... using GeneXus.

Transcription

1 1. How to implement applications for Smart Devices... using GeneXus. 2. Let s suppose that we need to develop a simplified application for a real estate agency... 1

2 This real estate agency works with certain neighborhoods and areas in a city, and it offers houses and apartments for sale and for rent. It has real estate agents who sign property sales and rental agreements with clients... To manage all this information, the real estate agency needs a computer system that records neighborhoods, properties, clients, agents and agreements: that is, all the entities it works with. 3. To make it accessible from any browser and from any location with Internet access, and with no infrastructure requirements, we can implement it in a cloud. The system will have a restricted area that can only be accessed by the real estate agency s staff (known as backoffice or backend), and is used to enter and work with information about neighborhoods, properties, agents, clients and agreements. In addition, it will have a public access area where visitors looking to buy or rent a property can view the list of available properties, filter the data they are interested in and eventually coordinate a visit. This is known as frontend. Since there are almost no functional differences between the backend and frontend implementation, we will only focus on the backend. 4. 2

3 5. It can have a web-based part implemented in Ruby, Java or.net... to be used from a browser. In addition, to support the agents' mobile work, part of the application will be implemented for smart devices. The programming language will depend on the device used. If we want to develop this application and sell it to various real estate agencies, we can t create it for one device in particular. But... does this mean we have to program it in the languages of each device?! 3

4 No, if we do it with GeneXus. Just like when we wanted to develop a web application... We will program the application in GeneXus and it will build it in the language of one or more devices selected. 6. How? The first thing to do is represent in GeneXus the entities of reality that will be used by the application: agents, clients, neighborhoods and properties. How can we do this? We create a GeneXus transaction object for each entity... and in each object we define the information that will be recorded about each one of them (their attributes)... For which part of the Backend? 7. 4

5 The Web or Smart Devices? Both!! Let s open GeneXus... We will show how to create the KB (with a Ruby prototype) and the Property transaction. If you are already familiar with these topics, you can move on to the next video that explains how to prototype in the cloud. (In GeneXus:) We create a knowledge base and call it RealEstateAgency. It will contain all the necessary knowledge to implement our backend. 5

6 We have to choose the default generation platform. Let's choose the default one, Ruby. Now we can start creating the transactions identified before. We will work with the Properties transaction, and we will focus on it for a while. The other transactions are very similar. So, we create the new GeneXus object... the Property transaction. We create its identifier attribute and define a domain called Id, which will be applied to all the other identifiers. Let s take a look at it among the predefined domains. 6

7 We can set it to be an autonumbered domain so that all the attributes based on this domain are automatically numbered. Next, we enter the attribute that will represent the property name. It is of character type so we can create a domain called Name in order to reuse it in other attributes that also store names. We will record the date when the property was entered into the system; it is of Date data type: 7

8 Next, we add the PropertyAddress attribute. As we can see, it automatically takes the predefined domain which is Address. Next, we need an attribute to record a photo of the front of the property. It will be of Image data type. Lastly, we need an attribute to record the type of operation, which can be sale or rent. It will be an enumerated domain with two possible values: Sale and Rent. 8

9 We could go on adding the other attributes required by reality... However, this is enough for this demo. We can also add some business rules to this transaction:... assign today s date as default value for the date on which the property is entered into the system, an error... in case the address field is left empty, and a message... to inform the user that the property name field has been left empty... We save. Below we can see the default web interface automatically created by GeneXus for this transaction: 9

10 Go back to ppt slides So far, we have only told GeneXus that at some point we will ask it to generate the web application in Ruby. Therefore, after creating the transactions, GeneXus will have to implement them in this platform. 10

11 To do so, we still have to complete the environment settings: for example, specify a location for the database and a name for it, among other things. We could store the programs and database locally... or in the cloud... We will do the latter just by changing a property value. This will be the topic of the next video... Second video Previously... We had stated our problem: to build a web backend and another backend for smart devices, for a real estate agency. We started by creating the KB in GeneXus and a transaction called Property. 11

12 So far, we have only told GeneXus that at some point we will ask it to generate the web application in Ruby. Therefore, after creating the transactions, GeneXus will have to implement them in this platform. To do so, we still have to complete the environment settings: for example, specify a location for the database and a name for it, among other things. We could store the programs and database locally... or in the cloud... We will do the latter just by changing a property value. To do this we will open the Preferences area in the knowledge base. In the Default generator properties (which in our case is Ruby), we look for the Deploy to Cloud property that is set to No by default. We change it to Yes. 12

13 Just by doing this, all the necessary information will be automatically configured for the cloud. Everything is now ready to try our web application in Ruby. We press F5 to have GeneXus generate it. 13

14 As we can see, GeneXus shows the tables that will be created in the database in the cloud. In our case, it will be the table that the Property transaction will work on. We select to create it. GeneXus creates the table and the Ruby programs for our transactions (in this case we have one called Property). Next, it uploads them to the cloud and opens a browser with the development menu automatically created for us to run our objects and give them a try. This menu is known as Developer Menu. If you are already familiar with web development in GeneXus, you can skip this part and move on to the next video. For the sake of example, we will enter a property. We can see the web interface automatically created by GeneXus. 14

15 We don t assign an ID because it will be autonumbered. If we try to leave this field... we are warned that it is empty. We enter a name. We can see that the entry date has today s date as default, due to the default rule that we created before. We could change it or leave it as it is. If we try to leave the address field without entering a value, the error rule doesn't allow us to do so. We enter an address. Now we select a photo of the front of the house. Lastly, we select an operation. We confirm. We can see that the property has been successfully entered into the system. 15

16 In this way, we could continue developing the entire web backend. But... what about the backend for mobile devices? What kind of application do we have in mind for the Smart Device? 16

17 This will be the topic of the next video. Third video In previous videos... We had stated our problem: To build a backend for a real estate agency to be used on the web and Smart Devices. To do this we had started by creating a KB and the Property transaction, and had set the web backend to be generated in Ruby, in the cloud. Next, we had GeneXus build the application and finally entered a property into the system from a browser. 17

18 In this way we could continue developing the entire web backend. But... what about the backend for mobile devices? What kind of application do we have in mind for the Smart Device? It s an application that will be used by real estate agents. We begin with the simplest task... An agent needs to see the list of properties... 18

19 He selects a property from the list to see more details about the selected property... He may need to change some data... 19

20 How do we implement the panel to work with properties? In the transaction we go to the Patterns section and choose "Work With" from the patterns that can be applied to the transaction... this entity, that is to say, work with properties... will be used on Smart Devices, not on the web. 20

21 This pattern will implement the list of Real Estate Properties and for each property, its details. To do this, just like for all patterns, you only have to select the check box and save. 21

22 Here we can see what has been created... What do we have to do to generate and try our application for Smart Devices? Create a menu or point of entry (for the web, it was automatically created by GeneXus: it was the Developer Menu): To make this entry menu for Smart Devices, we create an object of Dashboard type. 22

23 We add an item to invoke the Work With Properties pattern created before... 23

24 And we configure its properties, for example, if we want the icon to be displayed with a customized image when tapping on the screen. We import the image from a file... 24

25 We can change its description. Also, we can configure its header, the dashboard icon... At this point we can have GeneXus create the programs by just pressing F5... For which device? Since we haven t changed anything, it will be for the default option: Android As we can see, GeneXus opens an Android emulator for us to try the application if we don't have an actual device to do it. Here we can see the property that we had entered... At the same time, the developer menu is opened in the browser. In addition to the links to execute the web backend, it will have a QR Code and a Download link related to the SD application. Why? In order to load and install the compiled application in our device and try it there instead of using the emulator. 25

26 s We can send this URL to anyone who has a QR Code reader installed so that they can download and install the application to give it a try. Note that there s only one listed property, and it is the one that we added using the web Developer Menu. Tapping on it... shows its details. Since the address is an Address domain attribute, the application gives the option to view it in a map. 26

27 The image is shown because the application interprets this type of data and displays it correctly on the device screen. The real estate agent may want to change some of this data, for example, the type of Operation. To do so, he would have to edit this information......he changes the operation to Rent and Saves. He may even be visiting a property to add it to his property portfolio... 27

28 Note that since the identifier is autonumbered, it doesn t prompt the user to enter a value. We enter its name. Listing Date will assume today s date value by default (because of the Default rule that we stated in the transaction), so we don t need to enter a value. 28

29 But in case we want to enter a value, since it is of Date type, the application is able to understand its meaning and displays the "Date Picker", which is a device application to easily select a date... We now enter the address: The application is aware that the following data is an image, so it gives the option to take a photo at that moment using the device, or select one of the stored images. We take a photo of the property we have in front of us... Next, we leave the following field Operation with the Sale value and Save. Now we can see the new property in the list of properties. 29

30 Just like in the web backend, the business rules that we stated are triggered. For example, entering an address was mandatory. Note that if we want to delete it......we are not allowed to do so. We may want to filter the list by Rent operation... Or go back and make a wider search, for example, by address... 30

31 What information is being shown in the list? The property's image and name. We may want to show the address instead of or in addition to the name. This and other customizations can be easily and quickly made using GeneXus. In the Work With Smart Devices object, I open the section that implements the List of Properties Layout... In addition to the name, I add the address... 31

32 I Save and press F5 to have GeneXus generate the application again

33 This is a small example of how easy it is to customize the application. We have been able to create what we wanted: one part of the web backend and another part running on the Smart Device... With some easy steps, we can have GeneXus generate the same application for devices with ios or Blackberry operating systems, just like we can have the Web application generated for Java or.net instead of Ruby. 33

34 Let s see some real life examples... And there s a lot more: Would you like to add security features? 34

35 ...or more entities which are interrelated? Would you like to customize what's being displayed, such as interfaces, the order in which data is displayed, the searches available? Do you need to add actions, such as scheduling visits on your calendar?...or add a client to the address list in the device? Or maybe send messages? To be continued... 35