I'm looking to create controls based on text boxes that validate numeric fields and restrict them to certain ranges without having to write all the callbacks for each control on the form.
Does anyone know of a tutorial on how to create and use such things?
Or alternatively, as I can't be the first person to have this requirement, are there a set of such controls available for use anywhere?
The simplest way is to use control arrays. Google turned up this tutorial. You could encode the minimum/maximum range into the Tag property of each individual control, or you could use the Index to look them up from arrays.
You can create a user-defined control in VB6 but I'm not sure it's worthwhile for this task. You have to write a lot of boilerplate code.
I think you can use the default text box, using the Validate event, or alternatively, if you need "live" checking then you could check in the KeyPressed, Change, etc events.
Related
I am trying to make a number of front panel decorations hidden in LabVIEW by the use of a boolean control. I have figured out how to do this with one object fine and have made it work with multiple items however it is not very elegant to say the least (see attached image). While in this case I only have 5 elements what if I had an elaborate front panel and had many more decorations I wanted to hide? There must be a better way to do this.
Thanks in advance.
Cheers
It works, just not very efficient....
As you might now you can use a for loop to iterate over array elements. What I would suggest is in the initialization code of your application put the controls of interest on to arrays, and when a user clicks a particular button iterate over those arrays to execute the visible non visible property node call on your decos and or controls of interest.
Heloo there? Is there any way to change the color [back and forecolor] of a Messagebox? Iam using VB6.0... Thanks in advance!
To the best of my knowledge, there is no way to do this. There is, however, a typical workaround.
The most common method for creating custom "message boxes" in VB6 is to create a new form in your project that acts specifically as a message box. You Show it when you need it, and then Hide or Unload it when the user clicks "OK" or "Cancel" or whatever. You can size the form the same as (or differently from) a MsgBox, create the buttons you want, make the colors as you choose, etc. Whenever you would have a message box pop up to tell the user something, you will instead call this form and change the text/color/other variables to whatever you need them to be.
This may seem annoying at first, but once you've done it once, it's very easy to see how useful a tool this new form template can become. It's code you might find yourself frequently reusing between various applications.
If you need any help with forms or form events, this is a pretty good basic tutorial which should tell you most of what you need to make this work:
http://www.vb6.us/tutorials/understanding-forms-vb6-tutorial
Good luck!
This is easy in .NET (not my question) but I'm trying to figure out if it is possible to simply change the text of a string in a Win32 list box control given an index.
There is a GetText function that takes an item index but nothing to change the text of an existing item/string. My workaround will be to remove it and add it back in the box (which is also a weird prospect since there is no single command to add a string + item data -- these must be done carefully by inserting the string and then setting the item data on the index of the inserted string, which is tricky (not possible?) with sorting active).
Yes, the lack of a LB_SETITEMTEXT message is a bit weird.
You should put your Delete+Insert+SetData calls between calls to WM_SETREDRAW...
At the risk of being off topic...
I tend to use the ListView control all of the time. You'll want it in report view to mimic a listbox, and, as a plus, it supports multiple columns.
Oh.. and it has a LVM_SETITEM Message :)
http://msdn.microsoft.com/en-us/library/bb761186(v=VS.85).aspx
Although this question is old, but I think this documentation presented by Microsoft will be able to answer anyone questions based on this one.
So according to Microsoft documentation which you can find here
Changes the text of a list-view item or subitem. You can use this
macro or send the LVM_SETITEMTEXT message explicitly.
void ListView_SetItemText(
hwndLV,
i,
iSubItem_,
pszText_
);
And it also presents other macros for managing the list box. You can build a wrapper around this macros to simplify handling list view controls, etc.
Does anyone have an example of using a QWidget as an editor in a QAbstractTableModel?
I have a column which when edited should create a QCombobox with the list of choices.
The docs seem to suggest I need to write a QAbstractItemDelegate and a custom paint function but that seems overkill to simply pop-up a standard QCombobox in Qt::EditRole.
Note - the combo box contents are the same for every row and it only needs to be shown when somebody clicks in the cell.
I know this should be simple but I can't get it to work. It's easy for a QTableWidget based table - but I need it for a very large data table.
The docs seem to suggest I need to write a QAbstractItemDelegate and a custom paint function but that seems overkill to simply pop-up a standard QCombobox in Qt::EditRole.
You don't need to go that far. One way is to subclass QStyledItemDelegate and then override createEditor() so that it returns your prepopulated combo box. Its setEditorData and setModelData functions will probably already suffice if you`re using basic Qt value types.
If you need something more generic that works across many different models, you can create a QItemEditorFactory that associates your editor with the correct type. This also works well with custom types.
When indicated by your view's EditTrigger, your view will get the delegate specific to the cell on which the edit is being invoked and call delegate->createEditor(...) which can then size the combo box according to the options parameter as well as set the current entry to the value specified by the model, although most of this should be handled by the QStyledItemDelegate. Thus, you won't have to worry about the Qt::EditRole directly as the view will handle that.
Did you try and have a look at the following example from Qt :
Spin Box Delegate Example
Maybe it will give you a much clearer view on the subject !
Hope it helps a bit !
How do I disable particular columns in MSHFlexgrid in VB6.0? I don't want my user to edit the values in a particular column.
I don't think the MSHFlexGrid control allows users to edit its data in the first place. Therefore, in effect, all columns are disabled. Job done :)
In fact, you have to add custom code to enable updating e.g. add an appropriate control (textbox, combo, date picker, etc) that does allow editing, hide it at design time, then at run time detect which grid cell should have focus, move and size the control to fit the cell then make it visible then handle events to validate the input then write the contents back to the recordset...
...or you could purchase a third party control that does all this out of the box. The MSHFlexGrid that ships with VB6 is essentially a cut-down version of VSFlexGrid Pro, which I've used and thought was quite good. It has a different way of handling hierarchical data by creating groups (rather than bands) which is superior, IMO. The best thing that can be said about the MSHFlexGrid is that it is easy to bind to a hierarchical ADO recordset to simply display the results but not good if you want to do nice formatting or make the grid editable. The VSFlexGrid Pro, if you can afford it, has more power e.g. you can create data source classes to handle binding to custom data structures (ships with VB6 examples of this including ADO recordset binding) which would be invaluable IMO if you intend to make your hierarchical grid editable.
'A Shortcut way is here... NOT in a proper way. But you can try
'if you need to lock the first 3 columns please use this code:
msf2=name of MSFlexGrid
Private Sub msF2_EnterCell()
With msF2
If msF2.Col = 0 Or msF2.Col = 1 Or msF2.Col = 2 Then
msF2.Col = 3
End If
End With
End Sub