The program WinDirStats (written in C++, see http://sourceforge.net/projects/windirstat/ ) has at the top a control that combines a tree-like structure (The column "Name", first on the left) with other types of data (graphic bar in column "Subtree percentage") and other text columns.
My question is, using Delphi 7, which control should I use to do something like that? It's the tree part that I find more difficult to get right.
The best control for this would most likely be Mike Lischkes Virtual Tree View.
Developers Homepage | Google Code Page
It's free
It gives you a tree connected with a list view
It allows for custom drawing
It's incredibly flexible
It's lightning fast
The only downside is that you have to learn a quite different paradigm than most Delphi controls have, but apart from that it is a teriffic control.
I myself have used it in various projects quite successfully and never hit a real roadblock while using it.
I also prefer Virtual Treeview, but here are some commercial alternatives:
ExpressQuantumTreeList
ElTree
TTreeList
Related
I have an existing application which is quite large, uses a SQL Server database and LINQ to SQL built in MVC. It does what it needs to do very well, but the CMS is sadly lacking (it's difficult, complicated to use and prone to errors).
I like the look of Composite C1 to migrate this application to so that my users can get a good CMS experience.
I don't really want to center my development around C1, so I've been looking at creating an MVC application:
http://docs.composite.net/Functions/MVC
I've created a sample controller, view and then returned some static data to the view and finally posted some data to the controller. All works as a "normal" MVC application would do.
Has anyone used this concept for a real world application? The idea is that if a user want's to display one of my controls on a page they just add the control via the Composite editor. I'll also add basic pages on installation.
It's a bit of a vague question, but I'm really looking for feedback on the following:
1) How "involved" do you need to be with Composite C1 stuff? I want to just create my controllers and other classes to do my work
2) How is the performance with this approach?
3) Is there many gotcha's that you've experienced?
I have built a larger application within/on top of a Composite C1 environment, so I can say its definitely possible and the compatibility with .NET application development is actually one of the main reasons why we chose Composite in the first place.
1) How "involved" do you need to be with Composite C1 stuff? I want to just create my controllers and other classes to do my work
You won't be able to completely ignore everything Composite related when developing a full fledged application however, simply because your controls/views/controllers will run on and be rendered by Composite C1. So necessarily some of the work is done at least in part by the C1 foundation you build on, e.g. Routing, Exception Handling or Rendering.
However you can usually work with or around those features without too much trouble. It may however take some understanding of how Composite works.
2) How is the performance with this approach?
So far I cannot say that Composite would slow down the application in any significant way. It may in fact support you in tasks like Output Caching.
3) Is there many gotcha's that you've experienced?
This is a very broad question, but you generally will always have to make sure you know whether something belongs in one of your controls or would be better fit into a Composite component (page, reusable html block). If you put things into the wrong place, the easiest things will become complicated (like creating a page link) due to information being not present in the current context. But as I said, you can solve this through clever design.
Another thing to look out for is that correct source versioning is a bit harder to set up in the first place with a Composite application, because you have to figure out what is content and what is application.
So far I have made good experiences with C1 and will be using it in the future. It may take a little more time to get into it in the first place compared to a vanilla ASP.NET application, but the work that is done for you regarding CMS parts is well worth it.
I have just been introduced to the LUA language, and I am embarking on my first project. However, the biggest challenge I am facing now is how to implement or make an Undo and Redo.
However, to make issues clear, the project is a Custom Text Editor, and as a result, the Undo/Redo here is required for editing any input text. I have manage to handle issues like Cut,Copy, Clear, Find Word, as well as Changing Font, Text Colour, inserting tables and images among others, and all these were handled in the lua language. Obviously, there are several of the custom text editors, i believe the effort to cater for many will pave the way for future advancements or improvements. But the Undo/Redo actions are tearing me apart, which from my research is even the lack by most of the existing custom text editors.
I have searched several forums where they all seem to give the tip of using an associative kind of table to load the information, and retrieve them from there. Unbelievably, i think some of these sites are just sharing their knowledge acquired from other sites without any technical view point or whatsoever. This is because, most of the suggestions i come across seem to look alike and the same in all aspect. For about tens of sites visited, there is non where a user has tried to post an example, but all i see is the same complain about the majority of lua users. Undoubtedly, this will seem a bit easy to some respected gurus in this forum.
I don't seem to get the true picture of the suggestions.
Can someone provide me with an example?
Undo/redo is a perfect fit for command pattern.
First you need to write some of the text manipulation functionality per se. Just the do part, without worrying about un- or re-. That will be lots of work in itself.
You will then have a bunch of functions to manipulate your document. Things like insertText(), setFont(), insertJpgImage() and such. The trick is that now you need to wrap each of this functions in a so called command object. Each command class must have a method to do() itself, and to undo() itself.
Now that all your text manipulation operations are represented by command objects, you execute each operation (e.g. bold some text) by something like:
boldCommand = setTextPropertyCommand:new(document, selectedArea, textProperties.bold)
boldCommand:do() --actually modify text
table.insert(commandUndoStack, boldCommand) --keep the command for possible undoing later.
When you want to undo the bolding of some text you can then call:
command = table.remove(commandUndoStack)
command:undo()
NB, if your are using some GUI framework binding in Lua, then it might be the case that this framework has its own readymade undo/redo functionality. For example Qt (with qtlua bindings) offers QUndoStack class.
We have developed a mildly sophisticated web application using JQueryUI and themes. We chose this approach because we could do it ourselves, using Themeroller to build a theme and JQueryUI classes or JQUI-aware plugins in Javascript, and have had very limited need to iterate over color schemes, fonts and other styling elements.
I've just started to receive input from our design staff, and want to create a workflow to allow for fluid changes in styling. What works for you?
Sadly good graphical/Ui designer, that is able to design/code in flash are rare jewels... For JavaScript: they are non-existent (at least for me in my country);
So the workflow that I work with (for designers) take this into account, and stays the same for my flash/JavaScript projects;
Roles
Firstly, from the designer point of view: there are 3 roles, as of followed.
1) the designer : in charge of artistic direction and graphical production.
2) the interface-r : works with the rest in implementing the graphics and animation.
3) the logic coder : Codes classes and functionality: logic isolated from interface.
Logic coder can have further sub roles, but is beyond the designer point of view. And roles should not be 100% enforced: it's good to learn and help from one another; The designer is not required to know coding, the coder does not need to know design. The interfacer however needs to know coding, and a bit of design: Not good: but know (especially animation)
work flow
1) Base functionality is worked out by everyone; while it is actually a coder role: getting everyone involved helps the idea generation progress (programers: the designers can sometime come up with really good wild ideas, your job is to logically see how it can be implemented and If it is worth doing so)
2) Mock up UI and Class interface This may be the worst UI you may ever seen, but it gives a general direction to work towards: This is done by everyone. With coder working out the isolated logic (no graphic at all; eg: sever logic) and the interfacer and designer does the mockup.
3.1) Graphic and animation the graphic designer works on their wonderful design / graphics. while the interfacer translate the designs to an actual interface (from photoshop to flash/HTML). If you are lucky, the designers would know how to do this even (slicing etc) and the interfacer focuses on implementation and animation. Any additional graphical animation (dynamic stuff, like something following or reacting to the mouse). Is to be discuss and developed by these 2. This process rarely involves the coder to step in.
3.2) The coder works on the logic while ensuring it correspond to a coding interface as agreeded with the interfacer. Focusing on getting the mockup fully functional (not the best looking). This is usually done by usually classes interface and/or global declaration (avoided if possible)
4) Interface merge The interfacer, then merges the 2 together: to form the final app. XD
Ending note
While in reality, after stage 2. The workflow goes in a contineous cycle of 3 and 4. The main advantage of having an interfacer, is to ensure the designer nor the coder slow the other down. Hence, limited slowdowns :) the interfacer however has a tough role, needing to be extremely flexible, and more often then not double as project lead in small teams. For only he will understand both sides and their limitations. Though he may not be alone nor the best at either.
Note this is used extensively in RAI when both sides are important roles. However if you have projects that has emphasis of 1 over the other. You will need to balance the manpower likewise (eg, a photographer interactive blog may mainly require the designer and interfacer to WOW instead, where most of the photo database code may be reused from already done or open source project (this is one of the most common job I encounter)
Is "Replacing non-visual components with code" a proven optimization technique in Delphi 7. Mainly with respect to Database Access.
The Web site you cite talks about replacing a dialog-box component with code that would display the dialog box without the use of any component. The alternative is to write a couple of lines of code to set up and display a dialog box whenever you need one, and to skip the component altogether. It's not really an optimization in speed or size, though. It's not a speed optimization since your code would do exactly what a component would have done anyway, and it's not a size optimization because the space any one component occupies in a program is negligible.
Database components aren't so easily replaceable as dialog-box components. Nearly everything in Delphi is designed to use descendants of the standard database components. If you don't use the components, then you won't be using any of Delphi's database capabilities at all. You can use the database libraries' native APIs if you wish, but I think that would be foolish if your goal is really optimization and you haven't identified the components as the source of your program's non-optimal behavior. Consider how much time and effort it would take you to rewrite your program without the database components.
I don't see how a form-based dataset/query/table/etc., would be faster or slower than one created in code. However, I like to put them in code as it's easier to maintain. I've seen screens with SQL embedded in a component, and then it's overridden in the code. Then I have to stop and investigate to determine which SQL is actually in effect. Sometimes the SQL in the form is good, sometimes it's used for a while and then trumped by the code, sometimes it's never active and the SQL is trumped in the formcreate. So I have to determine whether this is by design, or just sloppy leftovers. Also, it's easy to miss SQL changes in code reviews if they're in the .DFM and not the .PAS. i.e. I don't always look at the .DFM because I'm not interested in whether a label caption changed or a button moved.
So while it's nice for prototyping, when it comes to production code, you're better off having all of your database logic (SQL, table and field definitions) in the .pas file.
Update: I have finally given CnPack a try. Among the dozens of goodies, is a brilliant tool called "convert selected components to code". Form Design Wizard | More... | Convert Selected Components To Code. It does it all for you.
This is not a matter of being a component or not a component. If it comes to database access then BDE is extremely slow so changing it for sth else is a good move.
By the way - optimization is not about 'proven techniques' - it's about identifying a problem and solving it. If the problem happens to be slow db access then this is what you have to change.
Generally no. There is no additional overhead in using a non-visual component. It is created very quickly and works at runtime exactly at the same speed as one "created in code".
I'm looking for recommendations for a spreadsheet-like input facility to sit in an ASP MVC environment.
The client currently has a large number of very complex interlinked shared spreadsheets (which they are effectively running 90% of their core business from) for collecting and processing information. They wish to move this to a web application and require ASP MVC. They realise that they will not be able to display as much information on screen as they do currently with their spreadsheets, so a 40 x 60 grid should suffice in most cases. Of this they'll be a limited number of cells for data entry that will immediately update other cells in the grid using various spreadsheet-like formula. The grid must be AJAX enabled.
The quality of the user-interface is of primary concern here. As inevitably there will be a certain amount of resistance to move to database/web (and this project is a pilot anyway) the system must be as slick as possible. Almost as important is ease of implementation - the final system will be quite large so the quicker it is possible to configure the grid the better.
Either Open Source or commercial would be fine. HTML/Javascript, Silverlight and Flex implementations can all be considered.
I initially asked a similar question a year ago (it's taken that long for the client to agree the project) but I'm sure options have changed since then and our environment is now better defined.
I think Grapecity Spread will fit the bill , it can be easily built with MVC pattern and now it also supports the Razor View Engine .There is already a blog which details how to use Grapecity Spread with MVC , you can go through this here
http://www.gcpowertools.info/2011/12/using-grapecity-spread-for-net-with-mvc.html
Microsoft Silverlight. It is almost certainly your best bet for a rich line of business application with web deployment. It will allow you to utilise a consistent code base across your back-end and front-end component.
Whilst a number of commercial datagrid packages exist (Telerik, etc), I'd suggest using the default Datagrid component that is available, and understanding fully the databinding and templating options available.
Check out YUI's datatable, maybe what you need
http://developer.yahoo.com/yui/examples/datatable/dt_cellediting.html
I have used it and its great, very developer friendly and supports pagination.
When asked for a multi-line editable grid, I've done it two ways.
Dropped a SL control onto the page. This was incredibly easy.
A lot of javascript. Double-clicking a row made a row editable with several textboxes to span the gap. I don't think is what you're looking for, though.
For something quick and easy have a look at JqGrid demos to see if it can do what you want
http://www.trirand.com/blog/jqgrid/jqgrid.html
JQuery is already in MVC and being javascript it will work without plugins for the browser. However it may not be powerful enough for what you want in which case you going to need to look at Silver light etc. Could the project not be approached in a more web friendly manor?