/topic/75-multi-list-hack-chaining-crud-forms-together/
I have done some work on this now, and (much to my surprise) ... it worked pretty much first time around !!
Wonderful ! - I can now chain multiple CRUD forms together, and the display of the child forms works automatically whenever the parent is in edit or view mode.
Only took a small amount of code, and turned out to be pretty painless to do.
The API for this is as follows :[list=1]
[*]Write your controller to create a CRUD form as per normal. We will call this $crud1
[*]Before calling render() on the main CRUD, create another crud form, Lets say we call this $crud2
[*]call $crud2->chain_to($crud1, 'name_of_related_field', 'The title to go above the second form' (optional))
[*]Chain more forms together if you like, eg $crud3->chain_to($crud2, 'next_related_field','Title for the third form')
[*]When you are done, call $crud1->render() as per normal ... however the return value will include working CRUD forms for the child records as well.
[/list]
And thats all that is needed. Very simple to use.
When the main CRUD form goes into edit mode (or view mode as well if you have my patches applied to the library), then the secondary CRUD form is automatically loaded below this, in list mode. The second CRUD form is filtered automatically based on which parent record is being edited / displayed.
Internally, I am using a doubly linked list to connect the CRUDs together, so this allows for CRUDs to be chained together without limitation.
Here is the git patch to make this work. (to my already hacked v1.1.6 version of application/libraries/grocery_crud.php)
diff --git a/application/libraries/grocery_crud.php b/application/libraries/grocery_crud.php
index 566c275..a0ea4c2 100644
--- a/application/libraries/grocery_crud.php
+++ b/application/libraries/grocery_crud.php
@@ -1091,6 +1091,12 @@ class grocery_Layout extends grocery_Model_Driver
protected $css_files = array();
protected $js_files = array();
+
+ protected $parent_crud = null;
+ protected $child_crud = null;
+ protected $parent_key_field = null;
+ protected $parent_primary_key = 0;
+ protected $title = '';
protected function set_basic_Layout()
{
@@ -1104,7 +1110,11 @@ class grocery_Layout extends grocery_Model_Driver
protected function showList($ajax = false)
{
$data = $this->get_common_data();
-
+
+ if ($this->get_chain_depth() > 0) {
+ $this->where($this->parent_key_field,$this->parent_primary_key);
+ }
+
$data->order_by = $this->order_by;
$data->types = $this->get_field_types();
@@ -1112,7 +1122,6 @@ class grocery_Layout extends grocery_Model_Driver
$data->list = $this->get_list();
$data->list = $this->change_list($data->list , $data->types);
$data->list = $this->change_list_add_actions($data->list);
-
$data->total_results = $this->get_total_results();
$data->columns = $this->get_columns();
@@ -1394,11 +1403,19 @@ class grocery_Layout extends grocery_Model_Driver
public function get_css_files()
{
+ if ($this->parent_crud) {
+ // The top level parent supplies all the CSS files, so we dont have to add any more
+ return array();
+ }
return $this->css_files;
}
public function get_js_files()
{
+ if ($this->parent_crud) {
+ // The top level parent supplies all the JS files, so we dont have to add any more
+ return array();
+ }
return $this->js_files;
}
@@ -1831,7 +1848,7 @@ class grocery_Layout extends grocery_Model_Driver
return $buffer;
}
- $this->views_as_string .= $buffer;
+ $this->views_as_string .= $this->title . $buffer;
}
protected function get_views_as_string()
@@ -1841,6 +1858,37 @@ class grocery_Layout extends grocery_Model_Driver
else
return null;
}
+
+ /**
+ *
+ * Chain this CRUD to a parent CRUD .. it only displays when the parent CRUD is in edit or view record mode
+ * @param class grocery_CRUD $parent_crud
+ * @param string $field_name - name of field in this table which is a foreign key to the parent crud primary key
+ */
+ public function chain_to ($parent_crud, $field_name, $title='')
+ {
+ if (!is_object($parent_crud) || get_class ($parent_crud) != 'grocery_CRUD') {
+ die ("FATAL ERROR: Parent is not an object of class grocery_CRUD\m");
+ }
+ $this->parent_crud = $parent_crud;
+ $this->parent_key_field = $field_name;
+ $parent_crud->child_crud = $this;
+ $this->title = $title;
+ }
+
+ // Return the depth of chaining. 0 = top level, 1 = first chained crud, 2 = 2nd, etc
+ protected function get_chain_depth()
+ {
+ $retval = 0;
+ $crud = $this;
+ while (true) {
+ if (!$crud->parent_crud) {
+ return $retval;
+ }
+ $crud = $crud->parent_crud;
+ $retval++;
+ }
+ }
}
@@ -1930,17 +1978,42 @@ class grocery_States extends grocery_Layout
$segment_position = count($ci->uri->segments) + 1;
$operation = 'list';
-
$segements = $ci->uri->segments;
+ $num_hits = 0;
+ $depth = $this->get_chain_depth();
+ // echo "depth of $this->title = $depth\n";
foreach($segements as $num => $value)
{
+ // if ($depth > 0) {
+ // echo "check $num $value - hits = $num_hits\n";
+ // }
if($value != 'unknown' && in_array($value, $this->states))
{
- $segment_position = (int)$num;
- $operation = $value; //I don't have a "break" here because I want to ensure that is the LAST segment with name that is in the array.
+ // SteveOC 07-Jan-2012
+ // Break after the Nth occurance of a hit - where N = the depth of this CRUD in a chained heirachy
+ if ($num_hits >= $depth) {
+ $segment_position = (int)$num;
+ $operation = $value;
+ // J Skoumbouris has comment in original code ...
+ // I don't have a "break" here because I want to ensure that is the LAST segment with name that is in the array.
+ //
+ // Not sure why that is, maybe application specific ?
+ break;
+ }
+ $num_hits++;
}
+ $last_value = $value;
}
+ // echo "operation = $operation, posn = $segment_position\n";
+
+ if ($depth) {
+ // In ALL cases of a child crud being displayed, the previous segment examined is always the primary key value
+ // to filter on !!
+ $this->parent_primary_key = $last_value;
+ }
+
+
$function_name = $this->get_method_name();
if($function_name == 'index' && !in_array('index',$ci->uri->segments))
@@ -1949,6 +2022,7 @@ class grocery_States extends grocery_Layout
$first_parameter = !empty($segements[$segment_position+1]) || (!empty($segements[$segment_position+1]) && $segements[$segment_position+1] == 0) ? $segements[$segment_position+1] : false;
$second_parameter = !empty($segements[$segment_position+2]) || (!empty($segements[$segment_position+2]) && $segements[$segment_position+2] == 0) ? $segements[$segment_position+2] : false;
+ // echo "seg pos = $segment_position, op = $operation, param1 = $first_parameter, param2 = $second_parameter\n";
return (object)array('segment_position' => $segment_position, 'operation' => $operation, 'first_parameter' => $first_parameter, 'second_parameter' => $second_parameter);
}
@@ -2201,7 +2275,7 @@ class grocery_CRUD extends grocery_States
private $columns_checked = false;
private $add_fields_checked = false;
private $edit_fields_checked = false;
-
+
protected $default_theme = 'flexigrid';
protected $default_theme_path = 'assets/grocery_crud/themes';
protected $default_language_path= 'assets/grocery_crud/languages';
@@ -2817,6 +2891,8 @@ class grocery_CRUD extends grocery_States
*/
public function render()
{
+ $show_child = false;
+
$this->_load_language();
$this->state_code = $this->getStateCode();
@@ -2882,7 +2958,8 @@ class grocery_CRUD extends grocery_States
$state_info = $this->getStateInfo();
$this->showViewForm($state_info);
-
+
+ $show_child = true;
break;
case 3://edit
@@ -2902,7 +2979,8 @@ class grocery_CRUD extends grocery_States
$state_info = $this->getStateInfo();
$this->showEditForm($state_info);
-
+
+ $show_child = true;
break;
case 4://delete
@@ -3018,7 +3096,13 @@ class grocery_CRUD extends grocery_States
}
- return $this->get_layout();
+ $retval = $this->get_layout();
+ if ($show_child && $this->child_crud) {
+ // append the child Crud rendering to this content
+ $child_content = $this->child_crud->render();
+ $retval->output .= $child_content->output;
+ }
+ return $retval;
}
protected function get_common_data()
Attached file : my full version of grocery_crud.php, modifications applied from GC v1.1.6
--------------------------------
I am putting this patch up here for review and feedback as-is. Hopefully some of you can download it, have a play with the concept, and see if you can add any ideas.
So being a quick patch for testing, it is not perfect.
Known Issues :
1) GC is now up to v1.1.7 ... so my archive above does not include any of the fixes that have come through since v1.1.6. Please be aware of that if testing.
2) Johnny originally set things up so that in the URL, the LAST occurance of the operation is the one that grocery crud uses. Not sure why - he must have had a good reason for doing that. I had to change that behaviour to get this working, since there are now multiple operations encoded into the URL. This might break some applications ?
3) AJAX does not work on sub-lists at the moment. Not a huge problem as is, but I will get around to fixing that. Debugging AJAX on a good day can send you crazy - but doing in on a cascaded set of forms with multiple states all happening at once is another matter. Hopefully wont be too long fixing this.
4) Update / View / Insert / Delete all seem to work in sub-forms, and I havent seen a problem with it yet. Works nice. I do need to do a tonne more proper unit testing yet to _prove_ that it works in various situations, and catch any strange errors that might come up. So use this with test data only please, until it gets the stamp of approval !
--------------------------------------------
Summary :
This is a super useful addition to an already excellent library (built on top of a great framework). I really recommend that people have a play with it and see if it is useful for them, It is certainly useful for me !!
Chaining CRUDs together, and having the framework automatically link the displayed records with hardly any code is all pretty staggering really - its still early days with this toolset, but the power it gives to the programmer is just awesome.
Kudos to Johnny (and any other authors too), as this codebase is such a joy to dig into. Very very cool stuff !
. As I already read the code it will help for sure many people as a patch for the users as there are really many posts that asks EXACTLY this thing (there are almost 20 posts that want this patch). As for the issues, I have your answers below:
