dhtmlxconnector:extending [DHX documentation]

PHP Connector DHTMLX

Extending functionality

protocol details

data fetching

POST

Command parameters:

  • none

GET

Command parameters:

  • connector=true - flag of connector based request. The flag is set automatically, once you include the connector.js file on the page.
  • dhx_colls=field1,field2…fieldN - optional, can contain a list of fields for which collections will be requested. dhtmlxGrid use such parameters to request data for combo columns and select filters ( such requests are executed just once , for initial data loading)

    some.php?connector=true&dhx_colls=2,3 
  • dhx_sort[field]=directon - instruct server-side connector to sort dataset by defined field

    some.php?connector=true&dhx_sort[2]=asc 
  • dhx_filter[field]=mask - instruct server-side connector to filter dataset by defined field

    //filter by %test%
    some.php?connector=true&dhx_filter[2]=test

grid specific

Requsting part of data (Dynamic Smart Rendering or Dynamic Paging)

GET

  • posStart - position from which data is requested
  • count - count of requested rows

combo specific

Requsting part of data

GET

  • pos - position from which data is requested

Filter by label field

GET

  • mask - filtering mask for label field

tree/treeGrid specific

Requesting branch of tree

GET

  • id - parent id for requested branch

data updating (using dataProcessor)

GET

  • editing=true - mark of dataprocessor-based call

POST

  • ids - list of updated records
  • [id]_[property] - for each field inside updated record related field in POST is generated
  • [id]_!nativeeditor_status - action type

Back to top

porting connectors to another platforms

when should you use it?

The existing version of connectors supports a limited set of server platforms. In case database/framework/scripting language you'd like to use is not supported, you can port existing solution on your platform.

when shouldn't you use it?

Connectors are just wrappers around existing grid functionality, that's why if you need to use this solution once, you would better use grid API directly, instead of creating your own server connector.

implementation levels

Connector supports many operations implementing data processing. There is an opportunity to provide supporting basic operations and ignore higher-level ones, in case they are not used in your project.

basic support

Data assignment is basic connector operation which proceeds in the following way: connector connects to database, selects data and outputs this in stdout using XML format of the current component.

Key points:

  1. XML-data input must occur only after sending the appropriate http-header
  2. XML must start with XML declaration containing the appropriate data coding
  3. None other content must be sent to stdout (neither before nor after sending data by connector)

    header("Content-type:text/xml");
    print("<?xml version='1.0' encoding='utf-8' ?>");
    print(xml_formatted_data);
    • incoming parameters - there are no any;
    • restriction for output data - there is no restriction.

XML Format used by connector

Basic implementation allows to use resulting script as input parameter for load()/loadXML() methods.

 
Technically, there is an opportunity to use JSON or any other supported by component format, but you should bear in mind that complex scenarios are XML-oriented and you would better use XML

filtration and sorting

At this stage, the number of supported operations is considerably extended: you are allowed to use #connector_text_filter, sorting type 'connector' and filter/sort data through URL manipulations.

Key points:

  • An obvious advantage of this functionality can be estimated only for operating with grid, for other components such functionality doesn't seem to be necessary (it can be used only to filter/sort data through URL manipulations).
  • The level 'uses' code from the previous one. Beware, that now, before using XML, data is sorted/filtered according to incoming data.

GET

Command parameters:

  • dhx_filter - hash of filtering rules
    • filtration pattern - any entry( like %x% )
    • in case you have a few parameters, you should link them by AND logic
    • parameter is available only for fields with active filter
    • empty filter value means that filter wasn't set and it must be ignored

      // where field1 like %some% AND field2 like %other%
      dhx_filter[1]=some&dhx_filter[2]=other
  • dhx_sort - hash of sorting rules
    • possible values for asc and dsc parameters
    • in case you have a few parameters, you should link them by AND logic
    • order of filtering implementation - not defined, at the moment no one component is able to create multi-field sorting

      // order by field1 ASC, field2 DESC
      dhx_sort[1]=asc&dhx_filter[2]=dsc

      Hashes of rules in question use name of fields (where filtration is enabled) or columns' indices (in case of grid).

Restriction for output data: order and structure are defined through filtering/sorting parameters.

combo specific:
dhtmlxCombo has an additional filtering GET parameter:

  • mask - sets filtration in text label columns using “like x%” rule.

    some.php?mask=abc 

dynamic loading

After data output implementation goes dynamical loading. Dynamical loading has some particular features while working with hierarchical (tree/treegrid) and simple (grid/combo) components.

For hierarchical components, loading of data branch occurs at once.

some.php?id=123

Command parameters:

  • id - 'parent id' which defines the appropriate branch (beware, all filtration/sorting rules set while the previous stage are applied to component).

For other components, data will be outputted according to incoming parameters.

//grid
some.php?posStart=20&count=50
//combo
some.php?pos=50

Command parameters:

grid:

  • posStart - index of initial string
  • count - number of strings to output

combo:

  • pos - index of initial string
  • number of strings is defined by server settings

 
While working with grid, initial request (grid doesn't know yet how many strings are expected) doesn't contain any additional parameters ( 'posStart' and 'count' are not defined)

Back to top