cxGrid使用汇总3

32根据单元的值设置样式
解决：
procedure <aForm>.<aColumn>StylesGetContentStyle(
Sender: TcxCustomGridTableView; ARecord: TcxCustomGridRecord;
AItem: TcxCustomGridTableItem; out AStyle: TcxStyle);
begin
if ARecord.Values[AItem.Index] = aSomeValue then
AStyle := <aSomeStyle>;
end;

procedure <aForm>.<aView>StylesGetContentStyle(
Sender: TcxCustomGridTableView; ARecord: TcxCustomGridRecord;
AItem: TcxCustomGridTableItem; out AStyle: TcxStyle);
var
AColumn: TcxCustomGridTableItem;
begin
AColumn := (Sender as TcxGridDBTableView).GetColumnByFieldName('Email');
if VarToStr(ARecord.Values[AColumn.Index]) = '' then
AStyle := cxStyleNullEmail;
end;

======================================================================

TcxCustomGridTableView.FindItemByName, TcxGridDBTableView.GetColumnByFieldName or
TcxGridDBDataController.GetItemByFieldName

with cxGrid1DBBandedTableView1.DataController do
AValue := Values[FocusedRecordIndex, GetItemByFieldName('SomeFieldName').Index];

****************************************************************************
33动态生成BandedView
解决：
var
AView: TcxCustomGridView;
begin
AView := <cxGrid>.CreateView(TcxGridDBBandedTableView);
TcxGridDBBandedTableView(AView).DataController.DataSource := <DataSource>;
TcxGridDBBandedTableView(AView).Bands.Add;
with TcxGridDBBandedTableView(AView).Bands.Add do
begin
Visible := False;
FixedKind := fkLeft;
end;
TcxGridDBBandedTableView(AView).DataController.CreateAllItems;
<cxGridLevel>.GridView := AView;
end;
****************************************************************************
34当底层数据集为空时显示一条空记录
解决：
procedure <Form>.<cxGrid>Enter(Sender: TObject);
var
View: TcxGridDBTableView;
begin
View := TcxGridDBTableView((Sender as TcxGrid).FocusedView);
if View.DataController.DataSet.IsEmpty then
begin
View.DataController.DataSet.Append;
View.Controller.EditingController.ShowEdit;
end;
end;
****************************************************************************
35 在当前View插入记录
解决：
使用FocusedView属性得到当前焦点View，用View.DataController得到对应的Data Controller，
之后使用Data Controller的方法来操作数据：
- Append
- Insert
- Post
- Cancel
- DeleteFocused
- DeleteSelection

示例：
var
ARecIndex: Integer;
…
View.DataController.Append;
ARecIndex := View.DataController.FocusedRecordIndex;
View.DataController.Values[ARecIndex, SomeItemIndex] := SomeValue;
View.DataController.Post;

另外一种方法是使用View.DataController.DataSource.DataSet得到底层数据集后，再用数据集的方法来操作数据。
****************************************************************************
36激活内置编辑控件
解决：
1) <aView>.Controller.EditingController.ShowEdit(<aColumn>);
2) <aView>.Controller.EditingController.StartEditShowingTimer(<aColumn>);
3) <aView>.Controller.EditingItem := <aColumn>;
4) <aColumn>.Editing := True;
****************************************************************************
37隐藏内置编辑控件
解决：
<aView>.Controller.EditingController.HideEdit(True);
****************************************************************************
38 移除一个分组列
解决：
<aColumn>.GroupIndex := -1;
<aColumn>.Visible := True;
****************************************************************************
39 保存修改到数据库
解决：
procedure <aForm>.FormClose(Sender: TObject; var Action: TCloseAction);
begin
if (<aGrid>.FocusedView <> nil)
and (<aGrid>.FocusedView.DataController.EditState <> []) then
<aGrid>.FocusedView.DataController.Post;
end;
****************************************************************************
40设置内置右键菜单
解决：
内置右键菜单包括二个菜单:cxGridStdHeaderMenu, TcxGridStdFooterMenu
uses cxGridStdPopupMenu;

procedure TForm1.cxGridPopupMenu1Popup(ASenderMenu: TComponent;
AHitTest: TcxCustomGridHitTest; X, Y: Integer; var AllowPopup: Boolean);
begin
if ASenderMenu is TcxGridStdHeaderMenu then
TcxGridStdHeaderMenu(ASenderMenu).OnPopup := StdHeaderMenuPopup;
end;

procedure TForm1.StdHeaderMenuPopup(Sender: TObject);
var
I: Integer;
begin
with TcxGridStdHeaderMenu(Sender).Items do
for I := 0 to Count - 1 do
if Items[I].Caption = 'Group By Box' then
begin
Items[I].Enabled := False;
System.Break;
end
end;
****************************************************************************
41得到选中记录的值
解决：
1) View.DataController.DataModeController.GridMode = False时

RecIdx := View.Controller.SelectedRecords[i].RecordIndex;
ColIdx := View.DataController.GetItemByFieldName(AFieldName).Index;
OutputVal := View.DataController.Values[RecIdx, ColIdx];

//RecID := View.DataController.GetRecordId(RecIdx);
//OutputVal := ADataSet.Lookup(View.DataController.KeyFieldNames, RecID, AFieldName);

2) View.DataController.DataModeController.GridMode = True时
Bkm := View.DataController.GetSelectedBookmark(ASelectedRecordIndex);
if ADataSet.BookmarkValid(TBookmark(Bkm)) then
begin
ADataSet.Bookmark := TBookmark(Bkm);
OutputVal := ADataSet.FieldByName(AFieldName).Value;
end;

View.BeginUpdate;
View.DataController.BeginLocate;
try
// make changes here…
finally
View.DataController.EndLocate;
View.EndUpdate;
end;
****************************************************************************
42在GridMode禁用内置的右键Footer菜单
解决：
uses cxGridStdPopupMenu;

procedure cxGridPopupMenuOnPopup(...)
begin
if (ASenderMenu is TcxGridStdFooterMenu) and
<GridView>.DataController.DataModeController.GridMode then
AllowPopup := False;
end;
****************************************************************************
43主从表任何时候只能展开一个组
解决：
procedure TForm1.ADetailDataControllerCollapsing(
ADataController: TcxCustomDataController; ARecordIndex: Integer;
var AAllow: Boolean);
var
I: Integer;
C: Integer;
begin
AAllow := False;
C := 0;
for I := 0 to ADataController.RecordCount - 1 do
begin
if ADataController.GetDetailExpanding(I) then
Inc(C);
if C > 1 then
AAllow := True;
end;
end;

procedure TForm1.ADetailDataControllerExpanding(
ADataController: TcxCustomDataController; ARecordIndex: Integer;
var AAllow: Boolean);
begin
ADataController.CollapseDetails;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin cxGrid1DBTableView1.DataController.OnDetailExpanding:=ADetailDataControllerExpanding; cxGrid1DBTableView1.DataController.OnDetailCollapsing:=ADetailDataControllerCollapsing;
end;
****************************************************************************
44动态创建层次(Level)和视图(View)
解决：
var
Grid: TcxGrid;
Level: TcxGridLevel;
View: TcxGridDBTableView;
begin
// Creates a Grid instance
Grid := TcxGrid.Create(SomeOwner);
Grid.Parent := SomeParent;
// Creates a Level
Level := Grid.Levels.Add;
Level.Name := 'SomeLevelName';
// Creates a View
View := Grid.CreateView(TcxGridDBTableView) as TcxGridDBTableView;
View.Name := 'SomeViewName';
// … and binds it to the Level
Level.GridView := View;
// Hooks up the View to the data
View.DataController.DataSource := SomeDataSource;
// … and creates all columns
View.DataController.CreateAllItems;
end;

****************************************************************************
45获得Group Footer合计行对应的记录
解决：
procedure TForm1.cxGrid1DBTableView1CustomDrawFooterCell(
Sender: TcxGridTableView; ACanvas: TcxCanvas;
AViewInfo: TcxGridColumnHeaderViewInfo; var ADone: Boolean);
var
ALevel, ADataGroupIndex: Integer;
AGridRecord, AGroupRecord: TcxCustomGridRecord;
begin
if AViewInfo is TcxGridRowFooterCellViewInfo and // Row footer
(TcxGridDBColumn(AViewInfo.Column).DataBinding.FieldName = 'Area') then // Area column
begin
AGridRecord:= TcxGridRowFooterCellViewInfo(AViewInfo).GridRecord;
ALevel:= TcxGridRowFooterCellViewInfo(AViewInfo).Container.GroupLevel;
ADataGroupIndex:=Sender.DataController.Groups.DataGroupIndexByRowIndex[AGridRecord.Index];
if ADataGroupIndex <> -1 then
begin
AGroupRecord := AGridRecord;
while AGroupRecord.Level <> ALevel do
AGroupRecord := AGroupRecord.ParentRecord;
AViewInfo.Text := AGroupRecord.DisplayTexts[0];
end;
end;
end;

****************************************************************************
46访问过滤之后的记录
解决：
var
I: Integer;
begin
Memo1.Lines.Clear;
with cxGrid1DBTableView1.DataController do
for I := 0 to FilteredRecordCount - 1 do
Memo1.Lines.Add(DisplayTexts[FilteredRecordIndex[I], 0]);
end;

****************************************************************************
47获得单元的Font
解决：
cxGrid1DBTableView1.ViewInfo.RecordsViewInfo.Items[1].GetCellViewInfoByItem(
cxGrid1DBTableView1Company).EditViewInfo.Font;
****************************************************************************
48根据Level名称找到Level对象
解决：
function GetLevelByName(AGrid: TcxGrid; ALevelName: string): TcxGridLevel;

function LoopThroughLevels(ALevel: TcxGridLevel; ALevelName: string): TcxGridLevel;
var
I: Integer;
begin
Result := nil;
for I := 0 to ALevel.Count - 1 do
begin
if ALevel[I].Name = ALevelName then
begin
Result := ALevel[I];
Exit;
end;
if ALevel[I].Count > 0 then
begin
Result := LoopThroughLevels(ALevel[I], ALevelName);
if Result <> nil then
Exit;
end;
end;
end;

var
I: Integer;
begin
Result := nil;
for I := 0 to AGrid.Levels.Count - 1 do
begin
if AGrid.Levels[I].Name = ALevelName then
begin
Result := AGrid.Levels[I];
Exit;
end;
if AGrid.Levels[I].Count > 0 then
begin
Result := LoopThroughLevels(AGrid.Levels[I], ALevelName);
if Result <> nil then
Exit;
end;
end;
end;
****************************************************************************