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day three
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on day three we went out of base camp eGroupware and stepped into the high fields of eTemplates.

motivation

  • splitting design and layout
  • there is a dialog-editor (one part of the etemplate-app) to create the eTemplate
  • XSS security
  • no parsing of $_POST needed
  • no HTML knowledge needed
  • eTemplates can be (and are usually) nested, eg. a template-field can contain an other eTemplate
  • language independent interfacing: each field / cell of the template can have a label which is automaticaly run through lang() (the content of the field can be run through lang() too)
    • lang: the 2 or 5 letter language code (or empty for a non-language specific template)
    • the dialog editor can write all labels in a lang-file (merging it with the existing ones)
  • eTemplates have a name of the form app.function[.subtemplate] which is used to call them up
  • version: VersionNumbers like: '0.8.015'
  • they can have further keys, on loading the class picks the most appropriate one for a user:
  • group: the id of a group if the template is just for that group (that allows admin to show differnt views to each group)
  • template set: they belong too (if the template-set key is empty it is an default-template) they are stored in an array and in serialized form in the db-table 'egw_etemplate'
  • the dialog editor can dump all templates of an app for distribution (so they can be in the CVS too)
  • they encapsulate differnt UI (User Interface) types from the app: at the moment only a HTML one is ready, but a GTK one (using php-gtk, running as native app under linux and win32) and XUL is under development.


how to Setup our application the eGroupware way

There is a HowTo for eTemplates as well and a reference too.
The HowTo was helpful to get my first moves with eTemplate going, but we agreed to rewrite that part at least partially.

Lets consider we want to rebuild our old flagship test. Remember the folderstructure?!


test                                    that has to be identical to our app-name
        + setup                         files necessary for the setup Programm, give the webserver write-permission to that dir (on a development box only!)
        + inc                           class-files
        + templates                     templates, still needed to store the images and get around a lot of complains from the api
                + default
                        + images        here goes our images / icons


The optional file setup.inc.php in folder $app/setup?
$app/setup/setup.inc.php should contain the information to setup your application.


<?php
        $setup_info['test']['name']      = 'test';
        $setup_info['test']['title']     = 'Test';
        $setup_info['test']['version']   = '0.9.001';  //anything you like, as long as it is fitting the schema of a version number
        $setup_info['test']['app_order'] = 100;        // at the end
        // $setup_info['test']['tables']    = array('egw_test'); // if there are any
        $setup_info['test']['enable']    = 1;

        /* Dependencies for this app to work */
        // if you define dependencies, you MUST meet them to get that baby on the road
        $setup_info['test']['depends'][] = array(
                 'appname' => 'phpgwapi',
                 'versions' => Array('1.8','1.9'),
         );
        $setup_info['test']['depends'][] = array(   // this is only necessary as long the etemplate-class is not in the api
                 'appname' => 'etemplate',
                 'versions' => Array('1.6','1.8','1.9'),
        );



Since we had our original application registered manually, we should unregister our baby, to avoid version-number conflicts that may occur, since the manually registered application had no version number at all.
So
  • unregister the manually registered test application
  • log out of eGroupware
  • enter the setup of eGroupware in egroupware/setup
  • enter the required login information at Setup/Config Admin Login
  • check with the Step 4 - Advanced Application Management
  • click on Manage Applications
  • look for our test application, check with install
  • click on Save
  • if there are any errors, and there should be none (if you use eGroupware 1.3.012), ...
    • try to fix them.
  • log out
  • Go back to user-login
  • Apply sufficient rights for the application (This is done via the Admin dialog within eGroupware.)
  • call the test application.
It is still there nothing changed so far exept the way we handle the setup.
With the setup.inc.php we tell eGroupware how to handle our application, apply VersionNumbers and all the other fancy stuff we might need later on.

creating an eTemplate for the dialog

Now we need a nice edit dialog and use the eTemplate editor to set it up.
Assume that we wanted to name our first eTemplate index.

Step 1
start the etemplate app and type 'test.index' in the name field. Click on save in order to create the template as a new (almost empty) one.

Step 2
an (almost empty) empty template is displayed. An eTemplate can be thought off as a “grid”. The first cell may be a bit tricky to find, but will be highlighted when moving the mouse over it. On my computer this cell appears in pink as illustrated below. If you do not see anything, try selecting everything via Strg-A. You should see a small rectangle right below the horizontal rule below the button CSS-Style:

Step 3
doubleclick the small rectangle right below the horizontal rule below the button CSS-Style. You should see something similar to this:

Step 4
as type choose Text, as label name, as name name, add a blurText of your choice and maybe a help. You may set the dimensions of the textfield by setting the options to 20,40 (approximately 20 character visible, 40 character in available width):
Save your work.

Step 5
now we need a button to send our data that we collect to us. To accomplish this, we have to add a column to our grid.
  • Doubleclick on the label of our newly created name-text-field.
  • in the upper area of the properties window is a bar with three select boxes. Within the third one select insert a column behind.
  • Doubleclick on the label of our name-text-field.
  • in the third line of the properties window, klick on the tiny right-arrow behind the word grid.
  • choose Submitbutton, as label submit, as name submit
  • Save
Step 6
Create a widget before the grid
  • Doubleclick on the label of our name-text-field.
  • Click on the word grid
  • in the upper area of the properties window is a bar with two select boxes. Within the second one select insert a widget before.
  • select grid as type
  • Save
  • doubleclick the small rectangle right below the horizontal rule below the button CSS-Style (that is the newly created grid, first cell).
  • select text as type, Hello as label and who as name.
  • disable the cell within the grid-row attributes, by typing !@who in the disabled property
  • check the checkbox readonly to make it an read-only textfield. This has two effects:
    • for one thing the value of @who is not editable
    • the borders around the text-field vanish.
  • Save
Step 7
Now our first eTemplate is designed.
  • we have a input-field to enter text
  • we have a submit button to send our form somewhere (by default back to our very page).
  • we have a container to hold our response

ETemplate handles the complete form stuff for you. Data validation, parsing of the $_POST[...]
security issues, callbacks (e.g. for required field values, etc.
Doing all that, all you have to do, is handling the data.
The data are transported within the $content[...] array. Each name you assign within a eTemplate will respond to named entrys in the $content[...] array. Our name will be accessible via $content['name'] and "who" the field which was intended to hold and display the value of the submitted name via $content['who'].
While you control the content of the $content[...] array, you control the behavior of your eTemplate.

Step 8
In order to get your newly created eTemplate test.index going, you must call it from within your application. I realized that, from within a function.
This function is added to the class.test_ui.inc.php file.


function index($content=null)
{
    $debug=false;
    if (is_array($content)){
        $debug=true;
        // after submit
        $content['message']=print_r($content,true);
        $content['datetime']=time();
        $content['who']=$content['name'];
        $content['name']='';
        $content['ergebnis']=$content['wert1']*$content['wert2'];
    } else {
        // first call
        /*
        $content=array(
            'who'=>', please type a name ...',
        );
        */
    }
    $tpl=new etemplate('test.index');
    $tpl->set_cell_attribute('debuginfos','disabled',!$debug); 
    $tpl->exec('test.test_ui.index',$content);
    // the debug info will be displayed at the very end of the page
    //_debug_array($content);
}


Step 9
Since you want to be able to call that function from the eGroupware as function call or link or redirekt-link, you have to add the function name to the public_functions array.


var $public_functions = array(
    'testinterface' => True,
    'index'    => True,
    );


Step 10
You have to add a constructor to your test_ui class:


 // construktor
 function test_ui()
    {
      $GLOBALS['egw_info']['flags']['app_header']='test-Application';
      
      $this->tmpl =& CreateObject('etemplate.etemplate', 'test.index');
      $this->bo   =& CreateObject('test.botest');
      $this->html =& $GLOBALS['egw']->html;
                
      if(!@is_object($GLOBALS['egw']->js))
      {
           $GLOBALS['egw']->js =& CreateObject('phpgwapi.javascript');
      }

    }


Step 11
If we add echo "<a href='".$GLOBALS['egw']->link('/index.php',array('menuaction' => 'test.test_ui.index'))."'> Call the eTemplate version </a> <br>"; to our old function testinterface just before the creation of the footer, we have a link to start up our new eTemplate.
Sure thing, you can call your eTemplate - which is wrapped in a function from your test/index.php:
header('Location: ../index.php?menuaction=test.test_ui.index');

Step 12
If you wanted to have some fancy title for your Application, different from your application name. Set the app_header (as I did) within the constructor:
$GLOBALS['egw_info']['flags']['app_header']='My fancy application title';

Now we have our application converted to the eTemplate way of eGroupware. As you can see in the code of the function, I added a few fields to the eTemplate. You can see that I handle data of the $content[...] array and assign them to fields that I have not talked about.

The index function is called from our index.php file, from a link out of our old application or as callback for this form / dialog. In that case $content is an array with the content the user put into the fields of the dialog.

Let first have a look what happend if we called the first time (or what we do to show the dialog again with the changed data)


  • the $content array is set up with our internal data-array (which is empty on the first call) and the message
  • $readonlys: if a fieldname is set in $readonlys to True, its content is displayed readonly (for regular fields like type Text) or left out for buttons (we use this later)
  • at last we call etemplate::exec to show the template with the content from $content and set the function itself as callback for the dialog / form.

Now let's have a look what happens if the user submits the form and our callback is called.


  • the callback (this function) is not the submit-address of the form, the form get's always submitted to the function process_exec of the etemplate class. This function changes for some field-types the content (eg. a date-field consists of 3 single fields, process_exec takes care that it is delivered back as timestamp, as we set it in content before). It can even submit the form back to the user. In this case the callback is NOT called. The same is true if an int field contains letters or is not within the minimum or maximum set. For the specialist process_exec uses $_POST and ignores $_GET set as query in the url.
  • if $content['submit'] is set, the [Submit] button has been pressed ('submit' is the name NOT the label of the Submit button).
  • after that the content array is filled again as described above.

What do we have

Using the eTemplate we have now splitted the display of the userinterface from its processing code.
The structured developing techniques of the CodingRules - the 3-tier-approach (UI > BO > SO !!!) - enables us to split the layers of our application, and handle certain stuff at the right level (e.g. time -> user/system) and just there.


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