TMainMenu build menu item dynamic - delphi

On my system , the main menu is fully dynamic, is builded from data in the database.
I have a specific situation where some menu items need to be assembled before being displayed.
Let's assume that my menu has the following main items:
Files - Customer - Reports - About
When I click in Reports menu item must assemble the items before they are displayed.
I did an analysis of the code in TMainMenu, TMenu and TMenuItem class. Unfortunately I have not found a simple solution to the problem.
Exist a way to create these items before being displayed?

There is a trick you can use. You need to add one dummy TMenuItem under Reports and set its Visible property to False. Then add OnClick event to Reports item and do your populating logic there. Before you add new items you have to delete existing ones, but you should leave your dummy item intact.
Something like:
procedure TForm1.ReportItemClick(Sender: TObject);
var
Item: TMenuItem;
I: Integer;
begin
// Delete all items but first - dummy - one
for I := ReportItem.Count - 1 downto 1 do
ReportItem.Items[I].Free;
Item := TMenuItem.Create(ReportItem);
Item.Caption := 'abc';
// Item.OnClick := ...
// or
// Item.Action := ...
ReportItem.Add(Item);
Item := TMenuItem.Create(ReportItem);
Item.Caption := '123';
// Item.OnClick := ...
// or
// Item.Action := ...
ReportItem.Add(Item);
end;

Lets Suppose that you have an DS (TDataSet) how load all your data reports. And in the moment that you drop Reports Menu you can call UpdateMenuReport.
type
TMenuArray = array of TMenuItem;
var MyMenu: TMenuArray;
procedure TMain.MyClickPopupMenu(Sender: TObject);
begin
case TMenuItem(TMenuItem(Sender).Parent).Tag of
// do Something
end;
end;
procedure TMain.UpdateMenuReport;
procedure InitMyMenu(var AMenu: TMenuArray);
var i: Integer;
begin
if Length(AMenu)>0 then for i:= 0 to Length(AMenu)-1 do AMenu[i].Free;
SetLength(AMenu, 0);
end;
var j, i: integer;
begin
InitMyMenu(MyMenu);
Reports.Clear;
if DS.Active and (DS.RecordCount > 0) then
begin
SetLength(MyMenu, DS.RecordCount);
for i:= 0 to DS.RecordCount-1 do
begin
MyMenu[i] := TMenuItem.Create(Self);
MyMenu[i].Name := 'Reports_'+ IntToStr(i);
MyMenu[i].Caption := DS.FieldByname('NOM_REPORT').AsString;
MyMenu[i].Tag := DS.FieldByname('ID').AsInteger;
MyMenu[i].OnClick := MyClickPopupMenu;
end;
end;
end;

Related

Updating field in cxGrid acting strange

I have a function to update a cxGrid made with help from answers to Loop through records on a cxgrid and update a field/column
But it is sometimes acting a bit strange. If I open the form with the cxGrid and click the columnheader without doing anything else, the records are updateted OK. But if the 'selectorbar' is moved away from the top, the record marked is not updated.
I am sure it is a property that needs to be changed, but which one.
The variable fSelected is set to False at FormShow and is ther so that the user can unselect records as well.
procedure TfrmContactsSelect.colContactSelectedHeaderClick(Sender: TObject);
var
i: Integer;
Index: Integer;
BookMark : TBookMark;
Contact: variant;
begin
if fMulti = True then
begin
Screen.Cursor := crHourGlass;
fSelected := not fSelected;
BookMark := qryContacts.GetBookmark;
qryContacts.DisableControls;
try
for i := 0 to grdContactsView1.DataController.FilteredRecordCount - 1 do
begin
Index := grdContactsView1.DataController.FilteredRecordIndex[i];
Contact := grdContactsView1.DataController.Values[Index, 4];
if grdContactsView1.DataController.LocateByKey(Contact) then
begin
qryContacts.Edit;
qryContacts.FieldByName('fldcontact_selected').AsBoolean := fSelected;
qryContacts.Post;
end;
end;
finally
qryContacts.EnableControls;
qryContacts.GotoBookmark(BookMark);
qryContacts.FreeBookmark(BookMark);
end;
Screen.Cursor := crDefault;
end;
end;
Delphi XE7, DevExpress 14.2.2, UniDAC 5.5.12 for DB access
Comment:
I have ended up with the following solution based on the answer and input from MartynA
procedure TfrmContactsSelect.colContactSelectedHeaderClick(Sender: TObject);
var
i: Integer;
Index: Integer;
MarkedRecord: variant;
CurrentRecord: variant;
begin
if fMulti = True then
begin
Screen.Cursor := crHourGlass;
fSelected := not fSelected;
Index := grdContactsView1.DataController.FocusedRecordIndex;
MarkedRecord := grdContactsView1.DataController.Values[Index, colContactGuid.ID];
try
for i := 0 to grdContactsView1.DataController.FilteredRecordCount - 1 do
begin
Index := grdContactsView1.DataController.FilteredRecordIndex[i];
CurrentRecord := grdContactsView1.DataController.Values[Index, colContactGuid.ID];
if grdContactsView1.DataController.LocateByKey(CurrentRecord) then
begin
grdContactsView1.DataController.Edit;
grdContactsView1.DataController.SetEditValue(colContactSelected.ID, fSelected, evsText);
grdContactsView1.DataController.Post;
end;
end;
finally
grdContactsView1.DataController.LocateByKey(MarkedRecord);
end;
Screen.Cursor := crDefault;
end;
end;
I can reproduce your problem using the sample project I posted in my answer to your other q.
Try this: Add a TMemo to your form, and inside the 'if grdContactsView1.DataController.LocateByKey(Contact) then' block, write the value of a row-unique datafield and the Selected datafield value to the memo.
Then, what I get when some row other than the top row is selected is that one row is listed twice in the memo, with Selected both false and true, and one of the rows in the filter isn't listed at all, which I think accounts for the behaviour you're seeing. If I then comment out the .Edit .. .Post lines, it correctly lists all the rows in the filter.
So evidently doing the Selected field changes inside a block which iterated the FilteredRecordIndex property of the DBTableView is what's causing the problem.
Personally, I find that it goes a bit against the grain to modify dataset rows in code via a DB-aware control (because you usually end up fighting the DB-awareness of the control), but in this case, it's straightforward to do the processing via the DBTableView of the cxGrid.
procedure TForm1.ProcessFilteredRecords;
var
PrevV,
V : Variant;
i,
Index: Integer;
S : String;
begin
// First, pick up a reference to the current record
// so that we can return to it afterwards
Index := cxGrid1DBTableView1.DataController.FocusedRecordIndex;
PrevV := cxGrid1DBTableView1.DataController.Values[Index, 0];
try
for i := 0 to cxGrid1DBTableView1.DataController.FilteredRecordCount - 1 do begin
Index := cxGrid1DBTableView1.DataController.FilteredRecordIndex[i];
V := cxGrid1DBTableView1.DataController.Values[Index, 0];
if cxGrid1DBTableView1.DataController.LocateByKey(V) then begin
cxGrid1DBTableView1.DataController.Edit;
// 2 is the index of my Selected column in the grid
if cxGrid1DBTableView1.DataController.SetEditValue(2, True, evsText) then
Caption := 'OK'
else
Caption := 'Failed';
cxGrid1DBTableView1.DataController.Post;
end;
end;
finally
if cxGrid1DBTableView1.DataController.LocateByKey(PrevV) then
Caption := 'OK'
else
Caption := 'Failed';
end;
end;
Another way to avoid the problem is to change the Selected states in two steps:
Iterate the FilteredRecordIndex to build a list of rows to change - in your case this would be a list of guids
Then, iterate the list of rows and update their Selected states.
Code:
procedure TForm1.ProcessFilteredRecords;
var
V : Variant;
i,
Index: Integer;
BM : TBookMark;
S : String;
TL : TStringList;
begin
Memo1.Lines.Clear;
TL := TStringList.Create;
try
for i := 0 to cxGrid1DBTableView1.DataController.FilteredRecordCount - 1 do begin
Index := cxGrid1DBTableView1.DataController.FilteredRecordIndex[i];
V := cxGrid1DBTableView1.DataController.Values[Index, 0];
if cxGrid1DBTableView1.DataController.LocateByKey(V) then begin
if CDS1.FieldByName('Selected').AsBoolean then
S := 'True'
else
S := 'False';
S := CDS1.FieldByName('Name').AsString + ' ' + S;
Memo1.Lines.Add(S);
TL.Add(CDS1.FieldByName('Guid').AsString);
end;
end;
try
BM := CDS1.GetBookMark;
CDS1.DisableControls;
for i := 0 to TL.Count - 1 do begin
if CDS1.Locate('guid', TL[i], []) then begin
CDS1.Edit;
CDS1.FieldByName('Selected').AsBoolean := True;
CDS1.Post;
end
end;
finally
CDS1.EnableControls;
CDS1.GotoBookmark(BM);
CDS1.FreeBookmark(BM);
end;
finally
TL.Free;
end;
end;
Like you, I was expecting that changing a property or two of the cxGrid might avoid the problem without any code, but I haven't been able to find anything which does.

Programatically enable a menu item (and all it's parents) - Delphi

I need to selectively enable certain menu items based upon the status of the user. I've managed to get code to enable the actual items I want but I can't see how to enable all the parent menu items above each one that I enable in a multi-level menu. Without enabling them as well the menu item still can't be used as the user cannot reach it.
eg if I have
EditTop
EditSub1
Editsub2
EditSubSub1
EditSub3
I can enable EditSubSub1 but I also therefore need to enable Editsub2 and EditTop as well or it can't be reached by the user. That's what I would appreciate help with.
The code I have at the moment is the following (Assume that other code has given me a TstringList containing the menu names I want enabled)
First some code to disable everything.
procedure DisableMenu(AMenu: TMenuItem);
//recurses through all the menu and disables eveything
var
i: integer;
begin
for i := 0 to AMenu.Count - 1 do
begin
AMenu[i].enabled := false;
DisableMenu(AMenu[i]);
end;
end;
Then code that searches for and returns a TmenuItem based upon its name
(This came from
http://www.delphipages.com/forum/showthread.php?t=45723)
function FindMnuItem(Menu: TMenu; MenuName: string): TMenuItem;
procedure FindSubItems(mnuItem: TMenuItem);
var i: integer;
begin
for i:=0 to mnuItem.Count- 1 do
if mnuItem.Items[i].Name= MenuName then
begin
Result:= mnuItem.Items[i];
break;
end
else
FindSubItems(mnuItem.Items[i]);
end;
var i: integer;
begin
Result:= nil;
for i:= 0 to Menu.Items.Count -1 do
begin
if Menu.Items[i].name = MenuName then
begin
Result:= Menu.Items[i];
break;
end
else
if Result<> nil then
break
else
FindSubItems(Menu.Items[i]);
end;
end;
Finally the code I would like some help with. This selectively enables each menu item based upon the names in the Stringlist AllowedMenus but only those ones, not the ones above each one in the tree. How do I do that?
//first disable all menu items
DisableMenu(MainMenu1.Items);
//now enable the ones we want enabled
for i := 0 to AllowedMenus.count-1 do
begin
MenuName := AllowedMenus[i];
FindMnuItem(MainMenu1, MenuName).Enabled := true; //enable an item
end
All you need to do is walk up the menu tree using the TMenuItem.Parent property.
var vMenuItem : TMenuItem;
[...]
//first disable all menu items
DisableMenu(MainMenu1.Items);
//now enable the ones we want enabled
for i := 0 to AllowedMenus.count-1 do
begin
MenuName := AllowedMenus[i];
vMenuItem := FindMnuItem(MainMenu1, MenuName);
while Assigned(vMenuItem) do
begin
vMenuItem.Enabled := true; //enable an item
vMenuItem := vMenuItem.Parent;
end;
end
i think that u can use this function;
(D21 is your Actual Items):
procedure UpdateMenuParent(MyItemMenu: TMenuItem);
begin
TMenuItem(MyItemMenu).Enabled := true;
if TMenuItem(MyItemMenu).Parent <> nil then
UpdateMenuParent(TMenuItem(MyItemMenu).Parent);
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
UpdateMenuParent(D21);
end;

How Add pickup list to DBGrid at run time?

i have a DBGrid and it is linked to client dataset when i assign a SQLQuery at run time
the DBGrid automatically assigns no of column. What i need is when DBGrid automatically assign columns i need to set one of those columns to assign a picklist.
can anyone help me?
the following procedure calls in the forms on show event. the form contains DataSource, ClientDataSet, SQLViewQuery (TSQLQuery), DatasetProvider and DBGridDetails (TDBGrid).
procedure TViewDetailsForm.ViewPendingAndReturnCheques;
var I : Integer;
slPickList:TStringList;
begin
slPickList := TStringList.Create;
slPickList.Add('Pending');
slPickList.Add('Returned');
slPickList.Add('Passed');
SQL := 'SELECT a.CHEQUE_NO, a.BANK, a.CHEQUE_DATE, a.AMOUNT,a.STATUS FROM CHEQUES a';
//refreshisng the DBGrid
SQLViewQuery.SQL.Clear;
SQLViewQuery.SQL.Add(SQL);
ClientDataSet.Active := false;
ClientDataSet.Active := true;
DBGridDetails.Columns[0].Width := _Block;
DBGridDetails.Columns[1].Width := _Block;
DBGridDetails.Columns[2].Width := _Block;
DBGridDetails.Columns[3].Width := _Block;
DBGridDetails.Columns[4].Width := _Block;
for I := 0 to DBGridDetails.Columns.Count - 1 do
begin
if DBGridDetails.Columns[I].FieldName = 'STATUS' then
begin
DBGridDetails.Columns[i].ButtonStyle := cbsAuto;
DBGridDetails.Columns[I].PickList := slPickList;
end;
end;
Show;
end;
Here's a sample app I just created in Delphi 2007 that demonstrates how to accomplish this. Here's all I did to set it up:
Click File->New-VCL Forms Application from the IDE's main menu.
Drop a TClientDataSet, a TDataSource, and a TDBGrid on the form.
Click on the form, and then use the Object Inspector to create a new OnCreate event handler. Add the following code:
procedure TForm1.FormCreate(Sender: TObject);
var
SL: TStringList;
begin
with ClientDataSet1 do
begin
FieldDefs.Clear;
FieldDefs.Add('OrderNo', ftInteger);
FieldDefs.Add('Status', ftString, 10);
CreateDataSet;
end;
ClientDataSet1.Active := True;
// Connect a datasource to the CDS
DataSource1.DataSet := ClientDataSet1;
// Connect the grid to that datasource to create the columns.
DBGrid1.DataSource := DataSource1;
// Create the picklist for the second column (Status)
SL := TStringList.Create;
try
SL.Add('Pending');
SL.Add('Returned');
SL.Add('Passed');
DBGrid1.Columns[1].ButtonStyle := cbsAuto;
DBGrid1.Columns[1].PickList := SL;
finally
SL.Free;
end;
end;
Run the application, click in the Status column in the grid, and you'll see the three choices added to the PickList above.
You can assign values to the dbgrid column picklist during the run time.
Below is the code:
procedure Tfrm1.FormShow(Sender: TObject);
var
slPickList:TStringList;
I: Integer;
begin
slPickList := TStringList.Create;
slPickList.Add('Pending');
slPickList.Add('Returned');
slPickList.Add('Passed');
for I := 0 to 2 do
begin
dbgViewAxiomClaims.Columns1.PickList.add(slPickList[i]);//assigning
end;
end;
Below is the result:

Displaying item when LVItemGetCaption is being called with EasyListView?

I am trying to implement virtual data mode with EasyListview
From the demo :
procedure TForm1.AddItems(Count: Integer);
var
i: Integer;
begin
// Add items to the listview. Actually the items are added to the first
// group. This group is created automatically when the first item is added.
LV.BeginUpdate;
try
for i := 0 to Count - 1 do
LV.Items.AddVirtual;
finally
LV.EndUpdate;
end;
end;
procedure TForm1.LVItemGetCaption(Sender: TCustomEasyListview;
const Item: TEasyItem; Column: Integer; var Caption: WideString);
begin
case Column of
0: Caption := 'Item ' + IntToStr(Item.Index);
1: Caption := 'Detail ' + IntToStr(Item.Index);
end;
end;
If I add some items which are string :
procedure TForm1.AddItems(Count: Integer);
var
i: Integer;
begin
// Add items to the listview. Actually the items are added to the first
// group. This group is created automatically when the first item is added.
LV.BeginUpdate;
try
for i := 0 to Count - 1 do
begin
LV.Items.AddVirtual.Caption := 'DISPLAY ME ' + IntToStr(i);
end;
finally
LV.EndUpdate;
end;
end;
How to get and displaying the stored virtual caption(=string) when LVItemGetCaption is being called?
If I get the caption with Caption := LV.Items.Items[Item.Index].Caption ; then Stack overflow.
You must add your data object to the item. E.g.:
type
TMyData = class
Caption: string;
end;
procedure TForm1.Button1Click(Sender: TObject);
var
i: Integer;
item: TEasyItemVirtual;
MyData: TMyData;
begin
EasyListview1.BeginUpdate;
try
for i := 0 to 100 - 1 do
begin
MyData := TMyData.Create;
MyData.Caption := Format('My Item %D',[i]);
item := EasyListview1.Items.AddVirtual;
item.Data := MyData;
end;
finally
EasyListview1.EndUpdate;
end;
end;
procedure TForm1.EasyListview1ItemGetCaption(Sender: TCustomEasyListview; Item: TEasyItem;
Column: Integer; var Caption: WideString);
begin
case Column of
0: Caption := TMyData(Item.Data).Caption;
1: Caption := TMyData(Item.Data).Caption;
end;
end;
And don't forget to free your object:
procedure TForm1.EasyListview1ItemFreeing(Sender: TCustomEasyListview; Item: TEasyItem);
begin
if Assigned(Item.Data) then
Item.Data.Free;
end;
Virtual nodes are ones that don't store their data. They're just views of data you are expected to already have in some other data structure of your program. When the control needs to display a node, it asks your program what text it should use by firing the OnItemGetCaption event.
In fact, it will call the event any time it needs to know the value of the Caption property, so when you try to handle the caption-fetching event by fetching the value of the caption, you trigger infinite recursion.

Delphi: Shift-Up and Shift-Down in the Listview

Is there a feature in the Listview control to shift items up and down?
Not having worked with TListView very much (I mostly use database grids), I took your question as a chance to learn something. The following code is the result, it is more visually oriented that David's answer. It has some limitations: it will only move the first selected item, and while it moves the item, the display for vsIcon and vsSmallIcon is strange after the move.
procedure TForm1.btnDownClick(Sender: TObject);
var
Index: integer;
temp : TListItem;
begin
// use a button that cannot get focus, such as TSpeedButton
if ListView1.Focused then
if ListView1.SelCount>0 then
begin
Index := ListView1.Selected.Index;
if Index<ListView1.Items.Count then
begin
temp := ListView1.Items.Insert(Index+2);
temp.Assign(ListView1.Items.Item[Index]);
ListView1.Items.Delete(Index);
// fix display so moved item is selected/focused
ListView1.Selected := temp;
ListView1.ItemFocused := temp;
end;
end;
end;
procedure TForm1.btnUpClick(Sender: TObject);
var
Index: integer;
temp : TListItem;
begin
// use a button that cannot get focus, such as TSpeedButton
if ListView1.Focused then
if ListView1.SelCount>0 then
begin
Index := ListView1.Selected.Index;
if Index>0 then
begin
temp := ListView1.Items.Insert(Index-1);
temp.Assign(ListView1.Items.Item[Index+1]);
ListView1.Items.Delete(Index+1);
// fix display so moved item is selected/focused
ListView1.Selected := temp;
ListView1.ItemFocused := temp;
end;
end;
end;
You have two options:
Delete them and then re-insert them at the new location.
Use a virtual list view and move them in your data structure.
My routine for doing the first of these options is like this:
procedure TBatchTaskList.MoveTasks(const Source: array of TListItem; Target: TListItem);
var
i, InsertIndex: Integer;
begin
Assert(IsMainThread);
BeginUpdate;
Try
//work out where to move them
if Assigned(Target) then begin
InsertIndex := FListItems.IndexOf(Target);
end else begin
InsertIndex := FListItems.Count;
end;
//create new items for each moved task
for i := 0 to high(Source) do begin
SetListItemValues(
FListItems.Insert(InsertIndex+i),
TBatchTask(Source[i].Data)
);
Source[i].Data := nil;//handover ownership to the new item
end;
//set selection and focus item to give feedback about the move
for i := 0 to high(Source) do begin
FListItems[InsertIndex+i].Selected := Source[i].Selected;
end;
FBatchList.ItemFocused := FListItems[InsertIndex];
//delete the duplicate source tasks
for i := 0 to high(Source) do begin
Source[i].Delete;
end;
Finally
EndUpdate;
End;
end;
The method SetListItemValues is used to populate the columns of the list view.
This is a perfect example of why virtual controls are so great.

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