Dan Dohotaru's Web Log

Google Dictionary is gone. Long live Search by provider

2011-08-08T19:38:00.001+02:00

... Google and friends in this episode

I don't know about you but I care about knowing what that %s word means beyond meanings.
Therefore I used to be a regular fan of google dictionary that seems to be defunct nowadays.

Though I never actually visited the site directly but always used predefined search engines for the url bar eventually achieving something like the one below

Sample for test

define d as a search engine using such an option (see url) in search engines settings (how to)
d + TAB + keyword + Return/Enter => results shown

While I was reading on gos about the soon long forgotten favorite web app of mine I remembered about the define keyword

Sample for test

define def as a search engine using such an option (see url while your millage may vary) in search engines settings (how to)
def + TAB + keyword + Return/Enter => results shown

What was that rambling again for?

Caching Opened Forms in .Net Compact Framework

2007-11-21T18:40:00.000+01:00

Recently i came across the necessity to create a multi form wizard style application for Compact Framework and realized that there is no such concept as OpenedForms (found this post also on Msdn Forums), so i had to do it on my own. For this i needed something generic, easy to handle with as little code as possible. In the same time i was preoccupied on having the same "look and feel" on all forms. Therefore i created a BaseForm with the visual styles i needed in all the other forms. Besides that have a FormController to handle the form creation and do all the caching. As you'll see in the test solution to achieve that all i needed to do was to overrite the OnLoad and OnClosing handler of the base form where i have the logic for adding or removing the forms from cache.
The following code is a snippet from the BaseFor

protected override void OnLoad(EventArgs e)
{
try
{
using (new WaitCursor())
{
base.OnLoad(e);
    if (this != null)
FormController.AddOpenedForm(this);
}
}
catch (Exception exception)
{
MessageBox.Show(exception.Message);
}
}
protected override void OnClosed(EventArgs e)
{
try
{
using (new WaitCursor())
{
if (this != null)
    FormController.RemoveOpenedForm(this);
base.OnClosed(e);
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}

The following code is a snippet for Form creation

public static T CreateForm() where T : BaseForm
{
T formToOpen = null;
try
{
foreach (BaseForm openedForm in openedForms)
{
if (openedForm.GetType() == typeof(T))
{
    formToOpen = openedForm as T;
    return formToOpen;
}
}
Type type = typeof(T);
formToOpen = Activator.CreateInstance(type) as T;
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
return formToOpen;
}

All in all, after having all that put in place, to create a new form (derived from BaseForm) and have it added to OpenedForms collection, all i needed to do was to write something like this


BaseForm form1 = FormController.CreateForm();
form1.Show();

and to close them i have several options, depending on the scenario


FormController.Close(form1);
FormController.CloseAllButThis(this);
FormController.CloseAll();

For details about all this or if you are curious about the implementation, download the TestSolution form here

Remove DataGrid auto selection on first row after binding

2007-11-16T13:07:00.000+01:00

Yesterday i had an issue related with having a filtering user control built with cascading datagrids (see image). Maybe not a very elegant idea, but it was a specific request from a customer, so i had to go that way.
It had to work like the following scenario: Clicking on one of the cascading dataGrids was suppose to bind only the entity clicked, while showing the next dataGrid filled with some filtered data based on the previous selection. Selecting an entity in the next grid would have repeated the scenario till the lowest level of the filters is reached. Clicking on the column header on the other hand should have reset the filter up to that level and hide the child grids. All in all, having a row selected or not (visually speaking) had a great impact on using the control, but unfortunately, after binding, a focused dataGrid auto selects the first row. Clicking on a row and then on the column header, made the first cell on the first row selected, while my scenario implied having nothing selected. I posted my problem on Msdn CF forums here and eventualy built a small application to demonstrate the behavior i wanted. The problem was still there, isolated from my project. I was already thinking about overriding the Paint events or something similar (dataGrid.Unselect(rowIndex) didn't work of course), while one of my colleagues suggested "Maybe it's a focus problem, set the focus on another control after binding". So now i have a dummy control (label with empty .Text property) which is programaticaly focused after binding. The grid looses focus, "clears the selection", my problem solved. Again, not a very elegant solution, but it's a quick workaround that solved my problem, at least for now
When i'll have the time, I'll take a dive into the DataGrid control and analyze what's happening behind the code.

You can download the test solution here, run it and see what i was facing with. Uncomment dummyLabel.Focus(); lines, and run it again. This time you'll have the behavior i was looking for.