Ext.ux.RowWithCellSelectionModel

I recently published another Ext JS extension at http://github.com/steffen/ext.ux.rowwithcellselectionmodel/ I want to let you know about.

Ext.ux.RowWithCellSelectionModel

This Ext JS extension enables the user to activate the editor of an editable cell in an Ext.grid.EditorGridPanel through a double click, to navigate through the cells via the cursor keys and select one or multiple rows through the mouse or through the cursor keys, if no cell is currently selected.
In summary, this selection model is a combination of the two built-in selection models Ext.grid.RowSelectionModel and Ext.grid.CellSelectionModel.
I created it out of the need to be able to add, edit and delete records in an EditorGridPanel. To delete one or multiple records, the user needs to select one or multiple rows which is not possible when using the default Ext.grid.CellSelectionModel.


Installation

Either
git clone git://github.com/steffen/ext.ux.rowwithcellselectionmodel.git
or download the files from http://github.com/steffen/ext.ux.rowwithcellselectionmodel/tarball/master
and put them in a public accessible folder.
Include the RowWithCellSelectionModel.js file in the header of your html page after the Ext JS files.



Usage

new Ext.grid.EditorGridPanel({
  ds: your_data_store,
  cm: your_column_model,
  sm: new Ext.ux.RowWithCellSelectionModel()
});

Alternatives

There exists another extension called Ext.ux.grid.RowAction by Jozef Sakalos, aka Saki, which enables you to add
icons with actions to grid rows. You can't delete multiple records at once, but it's worth a look. See http://rowactions.extjs.eu/ for more infos.

Ext.form.FieldSet and Ext.layout.CardLayout

This post is a note to myself and maybe to some others, since I today searched for the second time for a solution for a misbehavior (bug) in Ext JS when using an Fieldset inside a Panel which belongs to a Panel with a CardLayout.
When I set the Panel with the Fieldsets as the active item via panel_with_card_layout.getLayout().setActiveItem('form_with_fieldsets_panel') everything was shown/rendered besides of the form fields inside the Fieldsets.
After a little debugging and breakpoints fun in Firebug, I decided to search in the Ext JS Forum and luckily found the solution for that problem fast, thanks to the Forum's Google Search.

The solution is that you have to call panel_with_card_layout.doLayout() after setting the active item.

In conclusion, the following two lines should always go together when using FieldSets in a CardLayout:

panel_with_card_layout.getLayout().setActiveItem('form_with_fieldsets_panel');
panel_with_card_layout.doLayout();

Here's the note from an Ext Support Team member regarding this problem, which notes that there is another solution when you are using the Ext.TabPanel (which has the CardLayout as default Layout):

This is exactly why layoutOnTabChange was added to tabpanel. Unfortunately this fix wasn't added to card layout, so you'll have to call cardPanel.doLayout(); yourself after cardPanel.render('showcard');
Quote from http://extjs.com/forum/showthread.php?p=156627


Luckily, this is one of the rare bugs you'll run in when working with Ext JS. Pretty much everything else works as expected. :-) After all, a Friday the 13th could be worse. ;-)

Ext.apply and Ext.applyIf

In case you missed it, last weekend Jay Garcia released his third screencast in which he explains Ext.apply.

Here is the video, a short 7 and something minutes long, which is a fresh alternative of reading plain blog posts. :-)

Jay actually mentions a firebug bug which I wasn't aware of but which I encountered just this week after learning about it in his screencast. The bug is that the properties of an object you are inspecting (after clicking on the your object which is printed to your console via console.log(object) or console.info(object)) might not be the actual current ones. The work-around is to print directly the property you want to inspect via console.log(object.property).

If you're a little confused about the defaults (third) parameter of Ext.apply, then just think of it as you would write the the following

Ext.apply(receiver, defaults);
Ext.apply(receiver, source);

// is the same as
Ext.apply(receiver, source, defaults);

Also note that there is an Ext.applyIf method (without a third parameter) which only assigns properties/attributes to the receiver object if they aren't existing in the receiver object yet.

And as a small extra here's a real-world example of using Ext.apply which I implemented this week:

onBeforeLoad: function(store, options) {
  options.params = options.params || {};
  this.cleanParams(options.params);  
  var params = this.buildQuery(this.getFilterData());
  if (store.lastOptions && store.lastOptions.params) {
    options.params = Ext.apply(store.lastOptions.params, options.params);
  }
  Ext.apply(options.params, params);
}

I'm overwriting here the onBeforeLoad method from the excellent Ext.ux.GridFilter extension which is executed every time before the store is loading.
So if you load the store the first time via store.load({params: {start: 0, limit: 50}}), it will resend these parameters when the store is reloaded after you changed your filter values or after you manually executed store.load() after you saved changes to your EditorGridPanel for example. Moreover, the lastOptions params will be overwritten when you switch to the next page via your PagingToolbar, which calls something like store.load({params: {start: 50, limit: 50}}).

Ext JS Events, Observable and DomHelper slides

Want to learn more advanced stuff about how to use Ext JS?
Check out these slides from an Ext JS core developer named Aaron Conran. You might know him from the Ext JS forum.



First a very good and quick introduction to Javascript, where you learn more about strictly (not) equals such as === and !== which you encounter often in the Ext JS code and also some nice to know information about the difference between null and undefined.

| View | Upload your own

The next presentation teaches you about Ext JS Event Handling:

| View | Upload your own

Next a presentation about Ext JS Observable Class which includes a nice example of how to catch all fired events of an object and print them to your firebug console.

| View | Upload your own

Ext JS's Dom helpers should also be checked out!

| View | Upload your own

| View | Upload your own

Thanks Aaron for putting together these very helpful slides!

Ext.ux.PrinterFriendly, 0.2

I hope nobody minds if I post some update announcements for my Ext JS extension here in my blog. The next Rails-specific post is coming soon...

Here are the changes for version 0.2:

• Added config.js file for customized settings


• Added Ext.ux.PrinterFriendly.ENABLE_SHORTCUTS config option


• Added Ext.ux.PrinterFriendly.ROOT constant


• Added x-grid3-cell-first and x-grid3-cell-last class to header cells


• Added config parameter to printPreview to set config options for the print preview window, i.e. the title


• Added 'printer-window' id for printer window


• Added init.js file, which loads dynamically all other required files


• Added closeText and printText config option to PrinterWindow for localization purposes


• Added hiding of body until the printing layout gets initiated, this way the user doesn't see the page without the custom printer css, which the user might add in the onPrinting function


• Removed Ext.PRINTER_FRIENDLY_CSS_URL constant


• Changed all internal extensions to use Ext.ux.PrinterFriendly namespace


• Changed name of format parameter from format to _format, since it conflicts with the format parameter in Ruby on Rails


• Changed loading of printer friendly css file, will be loaded now when loading js scripts, which prevents the user from seeing the page before the css is loaded


• Fixed error in Safari in addStyleSheet method which caused that onPrinting is not executed


• Fixed print button for IE, IE is printing the content of the iframe now


• Fixed css bug in IE, empty cells will be filled with now, so that the css border is shown
  

The files can be found here.

Ext.ux.PrinterFriendly, 0.1 (Initial Release)

I'm happy to announce the first release of my (first) Ext JS extension.
Here are the facts:

Name
Ext.ux.PrinterFriendly

Version
0.1 (Initial Release)

Summary
Easily build printer friendly layouts and grids for your Ext JS pages.

Features

• Builds a normal html table (Ext.ux.PrinterGridPanel) based on your data store and column model, which saves a lot of cpu power and memory when printing large data sets. Moreover it shows all rows. (Remember, you can't use ext's pagination or scrolling on paper. ;-))
  


• Remembers the state of your grid, such as that hidden columns stay hidden in printer friendly view, keep their column order and keep the row sorting. (This is not really a feature of this extension, it just uses the fabulous Ext.state.Manager, but I think it's important to mention, since this was an important requirement for me.)
  


• Completely Javascript-driven, no need for extra server-side coding for printer friendly pages
  


• Enables easy debugging of your printer-friendly layout (just add ?format=printerfriendly to your page url to see printer friendly view)
  


• Enables adding your custom stylesheet for your printer-friendly format

Source
See attachments on this post (in the Ext JS Forum).

Documentation
http://extjs.com/learn/Extension:PrinterFriendly

Example
See attachments on this post (in the Ext JS Forum).

Feedback
Any Feedback via comments on this post in the official Ext JS forum or in this blog is welcome!

I hope you find this extension as useful as I do! :-D

Regards,
Steffen

Ext JS Screencast (Sketchcast) about Ext.extend and Ext.override

Jay Garcia from TGD innovations LLC started doing a series of screencasts (or so-called sketchcasts) about Ext JS. Here's his second one about Ext.extend and Ext.override. It's certainly an interesting way of doing a screencast using a (digital) whiteboard.



Check out his Blog at http://tdg-i.com which also includes some nice explained Ext JS examples.

Inspecting your Ext.onReady variables

In the Ext JS examples included in the Ext JS package, you'll find usually this code:

Ext.onReady(function(){
  ..
  var store = new Ext.data.SimpleStore({
    ..
  });

  var grid = new Ext.grid.GridPanel({
    store: store,
    ..
  });
});

Notice the var keyword in front of the declared variables! The var keyword is defining the variables as local variables. They are only existing in the scope of the anonymous function which is passed to the Ext.onReady method.
But what if we'd like to inspect the values of our local variables in firebug? We could set a breakpoint inside our anonymous function which will allow us to inspect these local variables. But it's a little annoying to do that everytime we're working on an Ext page.

Well, we just could remove the var keyword or use this.store. But that would clutter up our global scope which isn't that nice.

Here is a better solution I came up with today:

Ext.screen = {}

Ext.onReady(function(){
  var s = Ext.screen;
  ..
  s.store = new Ext.data.SimpleStore({
    ..
  });

  s.grid = new Ext.grid.GridPanel({
    store: s.store,
    ..
  });
});

With that solution all our local variables can be referenced by Ext.screen.variable in our firebug console, while keeping our global scope clean by using the Ext.screen namespace.