I would like to confirm user before closing a workbook, that is has draft changes. Is there any way to check if workbook is dirty and has to be saved in order not to lose any data?
The IWorkbook.IsModified property will flip to true when you make a change to a workbook (either programmatically or through the UI).
Note that any formula updates will not affect this property. So for instance, hitting F9 in the WorkbookView or calling IWorkbookSet.Calculate() to update volatile formulas like RAND or NOW will not mark the workbook as being modified). If you need to keep track of recalculation changes as well, you could handle the IWorkbookSet.EndCalculate() or WorkbookView.Calculate() events.
I found out, that the IWorkbook.IsModified property does not flip to true, if changes made to a cell are not confirmed by hitting return or selecting another cell. So how would I find out that changes have been made, when the user closes the workbook?
I found the solution myself in the mean time. And in my case it's quite simple. I just added a handler for the Form.Closing event and added the following line:
workbookView.ActiveCell.Activate ();
This makes the IWorkbook.IsModified property flip to true.
Related
if(TPoints->Filter == String(Lat1) + String(" < Latitude AND ")+
String("Latitude< ")+ String(Lat2) + String(" AND ")+
String(Lon2) + String("< Longitude AND ")+
String("Longitude < ") + String(Lon2));
else{
ShowMessage("Invalid Boundries");
}
First time using data access and control components.
TPoints is a TADOTable, results are listed in a TDBGrid. If possible I need to do more than just showing the filtered results (filtering code above) from database. How to go to a specific row or maybe cell and play with it?
To move to a specific record, you have to set the RecNo property of TADOTable.
In a database, moving to a specific field of a record (AKA a cell) does not mean much, unless you want to edit the content of it. The Edit() method of TADOTable can put a record into edit mode, but I'm not sure how you can choose a cell programmatically. It also depends on your design. Normally, the user can start the edit mode by double-clicking on a cell, which takes care of everything automatically. But, if you want to change the data without the user typing it, a TADOQuery and SQL statement is a much better choice.
Be more specific about what you want to happen on the screen and the user's interaction. That way, we can help you better.
By the way, you don't extract data from the grid itself, you extract it from a DataSet (TADOQuery or TADOTable) that the grid is attached to.
I'm building a messaging application. I update the badge count in the database via a sqlite trigger whenever any operation like insert/delete/read message happens.
Currently, though the value update in the DB happens asynchronously, I have no way to get notified about when the value changes in my application and hence am polling periodically.
Is there some way to setup an observer on a database value/publish some notification when a given value changes?
I know that I can do this easily by first updating the badge count in an in-memory property and then persisting the changes to the DB; but I am not very inclined to do this, since there are too many entry points for this value to change, and I don't want to add a SET property everywhere.
One possible option would be to define a trigger that is only called when this specific value in the database is updated. The trigger should then make a call to a user defined function you create in your app. You use the sqlite3_create_function function to add your own function to SQLite. Your trigger would like something like:
CREATE TRIGGER some_trigger_name
AFTER UPDATE OF some_column ON some_table
FOR EACH ROW BEGIN
SELECT my_custom_fuction();
END;
If needed, you can pass 1 or more arguments to your function.
Though that this might not be an option for you, Core Data does this well.
I'm having a great time playing around with knockout js and have just started to get to grips with adding custom bindingHandlers.
I'm struggling a bit with the update function of a 3rd party jqWidget gauge - I can only get it to animate the first time I update the variable. On each update after that it just sets the value directly.
I don't fully understand ko.utils.registerEventHandler() and what it does although I've seen it in a bunch of other examples. Is this what is causing the animation to break? How do I know which events to register from the 3rd party widget?
For some reason this works fine if I add a jquery ui slider that is also bound to the observable.
You can test this here: set the value a few times to see that it animates the first time and not after that.
http://jsfiddle.net/LkqTU/4531/
When you update the input field, your observable will end up being a string. It looks like the gauge does not like to be updated with a string value, at least after the first time.
So, if you ensure that you are updating it with a number (parseInt, parseFloat, or just + depending on the situation), then it appears to update fine.
Something like:
update: function(element, valueAccessor) {
var gaugeval = parseInt(ko.utils.unwrapObservable(valueAccessor()), 10);
$(element).jqxGauge('value', gaugeval || 0);
}
http://jsfiddle.net/rniemeyer/LkqTU/4532/
You would generally only register event handlers in a scenario like this to react to changes made by a user where you would want to update your view model data. For example, if there was a way for a user to click on the gauge to change the value, then you would want to handle that event and update your view model value accordingly.
I'm answering the
I don't fully understand ko.utils.registerEventHandler() and what it does
part of your question.
registerEventHandler will register your event handler function in a cross-browser compatible way. If you are using jQuery, Knockout will use jQuery's bind function to register the event handler. Otherwise, will use the browser Web API with a consistent behavior across browsers.
You can check it out on the source code.
Value field in ListBox table has String[64] type. Is there posible to expand this 64-characters limitation? I need to store some directory pathes there.
It's probably (never tried) possible in WiX to override the default schema of he ListBox table. I know in InstallShield I just go to the direct editor and adjust it. WiX has a template schema that is used to build the MSI and you might be able to use the Table element to redefine it. Or it might just give you an error message saying you are defining a well known table.
However, I'm not sure if there would be any side effects in the ListBox control if you exceed 64 char. I don't see anything in the MSI SDK saying what's allowed so I guess your milage may vary.
Here's a trick that you might like though. It's called the evil twin dialog trick. See, in MSI there's a bug that UI elements don't refresh very well and this trick works around it. Consider this:
Dialog1 with ListBox associated to property TESTPROP and Items One value 1 and Two value 2.
Textlabel that displayes [TESTPROP].
When start the dialog the text label is empty after clicking a row in the listbox. Click back and next and suddenly it has the expected text of 1 and 2.
Now create a clone of this dialog ( Dialog2 ) and put a control event on the Listbox of dialog1 that says NewDialog Dialog2 condition=1 and put a control event on the Listbox of dialog2 that says NewDialog Dialog1 condition = 1
Now when you run it the screen refreshes ( although with a big of an ugly flicker ) See it looks like it's the same dialog only it's really the evil twin dialog that's being transitioned to so that the data refreshes correctly.
Now for extra credit use your custom actions to do something like this
ListBox Item 1 Text C:\Pro...Foo\Bob value LISTBOXDIRPROP1
ListBox Item 2 Text C:\Pro...Foo\Ed value LISTBOXDIRPROP2
Property LISTBOXDIRPROP1 = C:\Program Files\Foo\Bob
Property LISTBOXDIRPROP2 = C:\Program Files\Foo\Ed
Then set your TextLabel to display [[TESTPROP]]. This tells it to get deference the value of the value of the property. In other words, TESTPRO = LISTBOXDIRPROP1 = C:\Proggram Files\Foo\Bob
This trick would allow you to display a line that fits the 64 char constraint yet gives additional information when the user selects it.
Is there any way to manually track the changes done to a clientdataset's delta and update the changes manually on to then db. i have dynamically created a clientdataset and with out a provider i am able to load it with a tquery, now user will do some insert update and delete operations on the data available in the cds, and at final stage these data(modified) should be post in to database by using a tquery(not apply updates)..
After populating your data set from the TQuery call MergeChangeLog so that the records do not stand out as newly inserted, and be sure that LogChanges is set.
Then when at the final stage, before updating the query with the dataset, set StatusFilter so that only the records that you want to take action on should be showing. For instance;
ClientDataSet1.StatusFilter := [usDeleted];
You can also use UpdateStatus on a record to see if it has been modified etc..
But be careful that, is seems that there will be multiple versions of a record, and it is a bit difficult to understand how the "change log" keeps track. And there also can be multiple actions on a record, like modifying it a few times and then deleting it.
Change:= TPacketDataSet.create;
Change.Data:= YourClientDataSet.Delta;
while not Change.Eof do
begin
Change.InitAltRecBuffers(False);
if Change.UpdateStatus = usUnmodified then
Change.InitAltRecBuffers(True);
case Change.UpdateStatus of
usModified: ;//your logic read codes in Provider.pas for further hint
usInserted: ;//your logic read codes in Provider.pas for further hint
usDeleted: ;//your logic read codes in Provider.pas for further hint
end;
Change.Next;
end;
Above should work regardless of number of modified
Cheers
Pham