Using Delphi XE7 and FireMonkey I am looking at simple ways of displaying (and editing) some object property values in a TGrid. I have followed the tutorial showing how to bind TGrid columns to object properties and using a TObjectBindSourceAdapter I have a neat, single row grid populated from my one object as they show in the example.
However, I will only ever have one object in the grid (a single row) so I would really like to turn my grid data through 90 degrees to give me two columns - a fixed 'Name' and an editable 'Value'. My object properties would then be listed vertically (effectively like the Object Inspector view).
Is there a LiveBindings way of doing this, or should I use another control such a TListView? I'm new to LiveBindings!
Thanks for any suggestions.
Related
I want to modify the default height of items in DevExpress VCL cxLookUpComboBox,
like we do with cxComboBox items (cxComboBox.Properties.ItemHeight).
(almost literally) from the DevExpress Q&A
The TcxComboBox and TcxLookupComboBox controls are very different.
TcxComboBox displays a simple List Box control as its dropdown
control, but TcxLookupComboBox contains a grid control with multiple
columns.
If you wish to have more control over the Lookup Combobox appearance,
consider using its advanced version - TcxExtLookupComboBox. This
control displays a regular TcxGrid's data-aware view as its lookup
list, so you can use properties like OptionsView.DataRowHeight to
set up required dimensions.
I am using TDBGrid for the first time.
I didn't even notice the Columns property in the object inspector and everything went just fine: the grid was filled.
Then I saw the Columns property and tried it. When I use the object insector to add items to the Columns property of the grid, they do not all of them show up at run time. To me, it looks like the FieldName property is important. It looks like it is correct, but there are no values in some columns.
If I leave this property blank (no columns at all) it seems that the control populates it itself at run time and I do see all the columns. I could live with that. When I set column titles at run time it works, but setting column width does not.
[Update] Thanks for the feedback. I am learning slowly. Now I see what is happening. I wanted three of the five columns to be calculated. Two are gotten from INNER JOINs and the third from an SQL 'cast' of SELECT ... FROM_UNIXTIME(<table>.time_stamp).
If I do not define the columns at design time then these values are populated at run time when I execute my SELECT. Cnn anyone tell me how to set things up at design time? Thanks
There is no difference in functionality between runtime and designtime set up columns. That is: what can be done designtime can also be done runtime, and vice versa.
When te Columns property is kept empty, the grid fills it by default with all fields it finds in the linked dataset, once the dataset is opened. All column specific settings, such as alignment, width, title caption, etc... are set to default, based on the type, length and name of the corresponding field. This is the lazy way which sure could be sufficient.
You could deside to use your own setup or modification of the columns property, for one or more of the following reasons:
Change the order of the dataset fields in which they must appear in the grid,
Truncate the width of text fields (especially VarChar fields or Char fields with a large length normally result in colums that are too wide for normal presentation and/or user interaction),
Change the alignment of the fields (normally numeric fields are right aligned by default),
Hide one or more fields from the dataset,
Etc...
These own settings can be done desingtime as well as runtime.
Using the designtime columns editor is the preferred and RAD way in need of these customizations. Open the editor by double clicking the grid or the property, or via the grid's context menu. If the linked dataset is active then the command Add all fields is enabled, which does exactly the same as if you did not select any field at all, i.e. the default behaviour as described in the second paragraph.
The best way to define the columns on a dbGrid is to doubleclick the dataset in order to create variables that the form knows about (persistent fields). You can edit various properties of these variables such as DisplayLabel, DisplayWidth and DisplayFormat.
You can also add calculated fields by double clicking on the dialog box which appears when you double click on the client dataset.
I would like to display a list of items with columns and bind them to some custom objects of mine. There is no ListView control in Firemonkey, so what is the recommended way of doing this? I'd like the columns to be easily resizable, but don't require editable items.
I've not used it but the TMS FireMonkey Grid may do what you want http://www.tmssoftware.com/site/blog.asp?post=230
I am struggling to assign a style to a TGrid within Delphi Firemonkey. Styling required is quite basic (ie. Align the text in a column and colour per value).
For background, I have created a TGrid, set the rows (eg 200), and added the number of columns (3 in this case). The columns have been labeled as "Code", "Company" and "Balance". As the grid does not contain values (like a TStringGrid), I am able to set the display value via the "GetValue" method (where I retrieve data from an external source). - The result is a list that is fast, and able to cope with a lot of data, the downside is I can not format the design at run time...
I am thinking that I may have to use "Styles"; that are new in FM. If this is the case however, I am not sure how I can reference the cell as it does not really exist as it is painted via the GetValue method when it needs to be drawn?
Any help appreciated,
Regards
Ian.
Ray Konopka's blog might help you here:
http://www.raize.com/Articles/FmxStringGridCellFonts.asp
You can apply a style to a Column by creating the OnApplyStyleLookup event to the column, but to set the font style and color etc you would still need to implement a OnApplyStyleLookup for the TTextCell's themselves too.
I posted a very similar query on Stackoverflow and then found a workable solution which I added here
firemonkey mobile grid with livebindings - changing TextCell text color at runtime XE5
I'm trying to create my first app based on FireMonkey, and I hit a wall.
The only virtual list control I can find is tGrid.
This component is pretty good, but I can not figure out how to extend or customize it.
I get that there is tCheckbox column, tImage column etc, but what if I need a ButtonColumn or something like this?
Also I would like to style a row, based on the state of the data it represents.
An Example: if the data that is represented in the row has "Error=True" it should be displayed in red.
Has anyone got a similar problem? Or found alternate virtual list/grid components? Or even just some tips on use of the tGrid component.
These components are pretty essential in all database apps so it should be a pretty common request.
Also just as a note, I don't think the TGrid supports Drag & Drop of rows?
I have looked at
Firemonkey version of VirtualTreeView
and
Firemonkey and large amounts of data
If you look at the sources, TCheckColumn is only 15 code lines. If you need to create your own column descendant class it's quite straightforward.
This is one solution, otherwise you can dynamically create some components in your cells and then cast the children when checking the props (TColumn.CellControlByRow() return a TControl and the children would be what you have put in there).
As you want to 'style' your row I would suggest you to write your own TColumn class, even if you can do painting in the OnPaint Event.