- Seriously - How to get information from a database table for android. For example, there is a "name" field, how to get its data.

Android
1

/ Seriously / How to get information from a database table for android. For example, there is a “name” field, how to get its data. Method getname () to string returns null.

2

Could you please post the code you use to retrieve the data and a screenshot which shows your table schema in Backendless console?

Regards,
Mark

3

[reply user_id=1][h4]Mark Piller wrote:[/h4]Could you please post the code you use to retrieve the data and a screenshot which shows your table schema in Backendless console?

Regards,
Mark[/reply][reply user_id=1]I can not find enough information to understand how to retrieve data from the database to a string on the android.[/reply]

4

Suppose you have table called Person which a column named “name”. To retrieve data from that table you do this:

  1. Declare class Person:
public class Person
{ 
  private String name;
  public String getName()
  {
    return name;
  }


  public void setName( String name )
  {
    this.name = name;
  }
}
  1. Then use this code to retrieve your Person objects:
Backendless.initApp( YOUR_APP_ID, YOUR_ANDROID_SECRET_KEY, "v1" );


AsyncCallback<BackendlessCollection<Person>> callback = new AsyncCallback<BackendlessCollection<Person>>()
        {
          @Override
          public void handleResponse( BackendlessCollection<Person> response )
          {
            
          }
    
          @Override
          public void handleFault( BackendlessFault fault )
          {
    
          }
        };
    
Backendless.Persistence.of( Person.class ).find( callback );

the “response” argument in the callback (handleResponse method) will have the objects with data.

Make sense?

5

Yeah, I did, but how to get a string of “response”?

6

Each instance of the Person class in the resulting collection will contain string property which you can obtain using the getName() method.

7

HandleResponse should include getName (), or both, please append your code.

8

See the implementation of the handleResponse method - it calls getName() from the Person class:

    AsyncCallback<BackendlessCollection<Person>> callback = new AsyncCallback<BackendlessCollection<Person>>()
    {
      @Override
      public void handleResponse( BackendlessCollection<Person> response )
      {
        List<Person> firstPage = response.getCurrentPage();
        
        for( int i = 0; i < firstPage.size(); i++ )
          System.out.println( "name - " + firstPage.get( i ).getName() );
      }


      @Override
      public void handleFault( BackendlessFault fault )
      {
      }
    };
    Backendless.Persistence.of( Person.class ).find( callback );