I am working on some code that scrapes a page for two css classes on a page. I am simply using the Hpricot search method for this as so:
webpage.search("body").search("div.first_class | div.second_class")
...for each item found i create an object and put it into an array, this works great except for one thing.
The search will go through the entire html page and add an object into an array every time it comes across '.first_class' and then it will go through the document again looking for '.second_class', resulting in the final array containing all of the searched items in the incorrect order in the array, i.e all of the '.first_class' objects, followed by all the '.second_class' objects.
Is there a way i can get this to search the document in one go and add an object into the array each time it comes across one of the specified classes, giving me an array of items that is in the order they are come across in on the page i am scraping?
Any help much appreciated. Thanks
See the section here on "Checking for a Few Attributes":
http://wiki.github.com/why/hpricot/hpricot-challenge
You should be able to stack the elements in the same way as you do attributes. This feature is apparently possible in Hpricot versions after 2006 Mar 17... An example with elements is:
doc.search("[#href][#type]")
Ok so it turned out i was mistaken and this didn't do anything different to what i previously had at all. However, i have come up with a solution, wether it is the most suitable or not i am not sure. It seems like a fairly straight forward for an annoying problem though.
I now perform the search for the two classes above as i mentioned above:
webpage.search("body").search("[#class~='first_class']|[#class~='second_class']")
However this still returned an array firstly containing all the divs with a class of 'first_class' followed by all divs with a class of 'second_class'. So to fix this and get an array of all the items as they appear in order on the page, i simply chain the 'add_class' method with my own custom class e.g. 'foo_bar'. This then allows me to perform another search on the page for all divs with just this one tag, thus returning an array of all the items i am after, in the order they appear on the page.
webpage.search("body").search("[#class~='first_class']|[#class~='second_class']").add_class("foo_bar")
webpage.search("body").search("[#class~='foo_bar']")
Thanks for the tip. I hadn't spotted that in the documentation and also found another page i hadnt seen either. I have fixed this with the following line:
webpage.search("body").search("[#class~='first_class']|[#class~='second_class']")
This now adds an object into the array each time it comes across one of the above classes in the document. Brilliant!
Related
I used to use "iter_dialogs" to get a list of available chats. But this method has stopped working. Can you suggest an alternative? And is it possible to get a list of report-bots to write to them later? I will be very glad of any help.
iter_dialogs() doesn't work anymore, as it has been replaced by get_dialogs(). See Pyrogram's Release Notes for v2:
Iter_ methods have been removed:* This means there is now only one way of iterating through items by using the respective get_* methods which are all turned into generators. Some of the methods have been renamed as well:
iter_history becomes get_chat_history().
iter_chat_members becomes get_chat_members().
iter_dialogs becomes get_dialogs().
iter_profile_photos becomes get_chat_photos().
As for your second question about report bots, I have no idea what you're talking about there. You might want to edit your question to add more detail.
This is one of those just-making-sure-I-didn't-miss-anything posts.
I have a TKinter GUI in Python 2.7.3 that includes a listbox, and there are circumstances where I'd like to directly modify the text of a specific item at a known index. I've scoured the documents and there's no lb.itemset() method or anything like it. As best I can tell I have two options, either of which would work but just seem kind of klunky to me:
lb.delete() the old item and lb.insert() the new value for it at the same index (including a step to re-select the new value if the old deleted one happened to be selected).
Create a listvariable for the listbox, then use get() and set() on it -- with a pile of replace/split/join acrobatics in between to handle the differing string formats involved.
Is there some simpler, more direct way to do it that I'm missing? Or have I turned up all the available options?
Assuming from silence that there's nothing I missed. I went with option 2 -- the acrobatics weren't quite as complex as I'd thought. I just created a behind-the-scenes list wrapped up in a class; every time I update the list, the class syncs up the content of the listbox by doing a ' '.join on the list then setting the listbox's listvariable to the resulting string.
I'm new to rails, and right now I've got a simple application with a controller and view. The page loads up and the controller does a ton of http requests (can't change this) and populates an array of structs. The controller sorts it and the view iterates through and displays it in a table.
I would like the user to be able to click one of several buttons and sort the data in different ways. Right now, I simply pass a :sort variable with a page reload, sort a different way and voila. But, I was wondering if there was a way to sort this array without having to repopulate it. This might be a super simple question and I'm just not searching for the right thing. Basically, can I pass the array back to the controller so it can sort and reload the page? Thanks for any help.
There is a good cast about sorting, I'm sure you find your answer here: http://asciicasts.com/episodes/240-search-sort-paginate-with-ajax
you can use JQuery table which will not fires the server request.
For Demo check
http://datatables.net/
I want to create a tagging system like seen here on Stack Overflow or on Quora. It'll be its own model, and I'm planning on using this autocomplete plugin to help users find tags. I have a couple of questions:
I want tags to be entirely user-generated. If a user inputs a new tag by typing it and pressing an "Add" button, then that tag is added to the db, but if a user types in an existing tag, then it uses that one. I'm thinking of using code like this:
def create
#video.tags = find_or_create_by_name(#video.tags.name)
end
Am I on the right track?
I'd like to implement something like on Stack Overflow or Quora such that when you click a tag from the suggested list or click an "Add" button, that tag gets added right above the text field with ajax. How would I go about implementing something like that?
I know this is kind of an open-ended question. I'm not really looking for the exact code as much as a general nudge in the right direction. Of course, code examples wouldn't hurt :)
Note I am NOT asking for help on how to set up the jQuery autocomplete plugin... I know how to do that. Rather, it seems like I'll have to modify the code in the plugin so that instead of the tags being added inside the text field, they are added above the text field. I'd appreciate any direction with this.
mbleigh's acts_as_taggable_on gem is a feature-complete solution that you should definitely look into a little more closely. The implementation is rock-solid and flexible to use. However, it is mostly concerned with attaching tags to objects, retrieving tags on objects, and searching for tagged items. This is all backend server stuff.
Most of the functionality you are looking to change (based on your comments) is actually related more to your front-end UI implementation, and the gem doesn't really do much for you there. I'll take your requests one-by-one.
If user inputs a new tag, that tag
gets added, if user inputs an
existing tag, the existing tag gets
used. acts_as_taggable_on does this.
Click a tag from suggested list to
add that tag. This is an
implementation issue - on the
back-end you'll need to collect the
suggested list of tags, then display
those in your presentation as links
to your processing function.
Autocomplete as user enters
potential tag. You'll use the jQuery
autocomplete plugin against a list
of items pulled off the tags table.
With additional jQuery, you can
capture when they've selected one of
the options, or completed entering
their new tag, and then call the
processing function.
Restrict users to entering only one
tag. This will be your UI
implementation - once they've
entered or selected a tag, you
process it. If they enter two words
separated by a comma, then before or
during processing you have to either
treat it as one tag, or take only
the text up to the first comma and
discard the rest.
When you process the addition of a
tag, you will have to do two things.
First, you'll need to handle the UI
display changes to reflect that a
tag has been entered/chosen. This
includes placing the tag in the
"seleted" area, removing it from the
"available" display, updating any
counters, etc. Second, you'll need
to send a request to the server to
actually add the tag to the object
and persist that fact to the
database (where the taggable gem will take over for you). You can either do this via
an individual AJAX request per tag,
or you can handle it when you submit
the form. If the latter, you'll need
a var to keep the running list of
tags that have been added/removed
and you'll need code to handle
adding/removing values to that var.
For an example of saving tags while editing but not sending to server/db until saving a form, you might take a look at the tagging functionality on Tumblr's new post page. You can add/remove tags at will while creating the post, but none of it goes to the database until you click save.
As you can see, most of this is on you to determine and code, but has very little to do with the backend part. The gem will take care of that for you quite nicely.
I hope this helps get you moving in the right direction.
The more I try to force the acts-as-taggable-on gem to work the more I think these are fundamentally different types of problems. Specifically because of aliases. The gem considers each tag to be its own special snowflake, making it difficult to create synonyms. In some cases it doesn't go far enough, if you want the Tag to have a description you'd need to edit the given migrations (which isn't hard to do).
Here's what I'm considering implementing, given the trouble I've had implementing via the gem. Let's assume you want to create a tagging system for Technologies.
Consider the following psuedo code, I haven't yet tested it.
rails g model Tech usage_count::integer description:text icon_url:string etc. Run the migration. Note the
Now in the controller you will need to increment usage_count each time something happens, the user submits a new question tagged with given text.
rails g model Name::Tech belongs_to:Tech name:string
Name::Tech model
belongs_to :tech
end
Then you could search via something like:
search = Name::Tech.where("name LIKE :prefix", prefix: "word_start%")
.joins(:tech)
.order(usage_count: desc)
.limit(5)
This is starting point. It's fundamentally different from the gem, as each tag is just a string on its own, but references a richer data table on the back end. I'll work on implementing and come back to update with a better solution.
The auto_complete_for dealio from script.aculo.us is great an all, but is there a way for me to selectively disable the fact that it always auto-selects the first item in the list?
The problem is that, if I want to type my own entry that is new, and novel, I don't want the first item in the list to be auto-selected. The reason is because when I TAB out of the field, it selects, and fills the text box with that first item.
I got around that, somewhat, by making the first item in the list the same as what I'm typing, but that's not perfect either, because the auto_complete list doesn't always update with every keystroke, depending on how fast I type. I've tried setting the list refresh rate to the lowest value (1 millisecond) but no go.
What I really want is an option in "auto_complete_for" that doesn't select that first item at all - the same way that Google Instant doesn't automatically select the first suggested search phrase - you have to arrow-down to select one.
Maybe I can do this via an HTML option that I'm missing?
Looking at the source, there doesn't appear to be an option for that, but I bet if you changed line 284 of controls.js to this.index = -1; it would do what you want.
Otherwise, it might be time to look for a different autocomplete widget.
If your requirements are too far away from the available plugin, then I guess there is no point in tinkering around. Its best to write your own JS code.
You might want to consider this: https://github.com/laktek/jQuery-Smart-Auto-Complete
or this : https://github.com/reinh/jquery-autocomplete
I'll add another alternative that works great with Rails 3:
http://github.com/crowdint/rails3-jquery-autocomplete
I recently implemented auto complete for more than a field for Rails 2.0.2.
The plugin I used is:- https://github.com/david-kerins/auto_complete . Not sure if it supports Rails 3.
I have also encountered issues on implementing the above scenario and have posted questions( Implementing auto complete for more than one field in Rails ; Implementing a OnClick kind of functionality and formatting wrt Rails Partial-Views ) on stackoverflow for the same, I have been lucky on getting things working for me based on my requirement.
Kindly refer to these questions, they might have relevance to your requirement.