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cxGrid使用技巧 转载自http://topic.csdn.net/t/20060106/09/4500997.html#

2009-07-07 16:09 393 查看
小技巧:用代码展开/收缩主从结构
Self.tvDepartment.ViewData.Expand(True);
Self.tvDepartment.ViewData.Collaspe(True);
注:tvDepartment为主表对应的TableView

技巧二:在内置右键菜单的后面增加菜单项

首先应在Form上加一个cxGridPopupMenu控件 以启用右键菜单
UseBuildInPopupMenus设为True

procedure TFormItemList.FormCreate(Sender: TObject);
var
AMenu: TComponent;
FMenuItem, FSubMenuItem: TMenuItem;
begin
AMenu := nil;
if cxGridPopupMenu.BuiltInPopupMenus.Count = 0 then
Exit;
AMenu := cxGridPopupMenu.BuiltInPopupMenus[0].PopupMenu; //第一个内置右键菜单(表头菜单)
if Assigned(AMenu) and AMenu.InheritsFrom(TPopupMenu) then
begin
TPopupMenu(AMenu).AutoHotkeys := maManual; //手动热键

//-------------------------
FMenuItem := TMenuItem.Create(Self);
FMenuItem.Caption := '-';
FMenuItem.Name := 'miLineForGroup';
TPopupMenu(AMenu).Items.Add(FMenuItem);

//展开所有组
FMenuItem := TMenuItem.Create(Self);
FMenuItem.Name := 'miExpandAllGroup';
FMenuItem.Caption := '展开所有组(&X)';
FMenuItem.OnClick := miExpandAllGroupClick;
TPopupMenu(AMenu).Items.Add(FMenuItem);

//收缩所有组
FMenuItem := TMenuItem.Create(Self);
FMenuItem.Name := 'miCollapseAllGroup';
FMenuItem.Caption := '收缩所有组(&O)';
FMenuItem.OnClick := miCollapseAllGroupClick;
TPopupMenu(AMenu).Items.Add(FMenuItem);

//-------------------------
FMenuItem := TMenuItem.Create(Self);
FMenuItem.Caption := '-';
TPopupMenu(AMenu).Items.Add(FMenuItem);

//过滤面板
FMenuItem := TMenuItem.Create(Self);
FMenuItem.Name := 'miFilterPanel';
FMenuItem.Caption := '过滤面板(&P)';
//自动显示
FSubMenuItem := TMenuItem.Create(Self);
FSubMenuItem.Name := 'miFilterPanelAuto';
FSubMenuItem.Caption := '自动(&A)';
FSubMenuItem.RadioItem := True;
FSubMenuItem.GroupIndex := 5; //指定同一组
FSubMenuItem.Checked := True;
FSubMenuItem.OnClick := miFilterPanelClick;
FMenuItem.Add(FSubMenuItem); //加入二级子菜单
//总是显示
FSubMenuItem := TMenuItem.Create(Self);
FSubMenuItem.Name := 'miFilterPanelAlways';
FSubMenuItem.Caption := '总是显示(&W)';
FSubMenuItem.RadioItem := True;
FSubMenuItem.GroupIndex := 5;
FSubMenuItem.OnClick := miFilterPanelClick;
FMenuItem.Add(FSubMenuItem);
//从不显示
FSubMenuItem := TMenuItem.Create(Self);
FSubMenuItem.Name := 'miFilterPanelNerver';
FSubMenuItem.Caption := '从不显示(&N)';
FSubMenuItem.RadioItem := True;
FSubMenuItem.GroupIndex := 5;
FSubMenuItem.OnClick := miFilterPanelClick;
FMenuItem.Add(FSubMenuItem);
TPopupMenu(AMenu).Items.Add(FMenuItem);

//自定义过滤
FMenuItem := TMenuItem.Create(Self);
FMenuItem.Name := 'miCustomFilter';
FMenuItem.Caption := '自定义过滤(&M)';
FMenuItem.OnClick := miCustomFilterClick;
TPopupMenu(AMenu).Items.Add(FMenuItem);

//过滤管理器
FMenuItem := TMenuItem.Create(Self);
FMenuItem.Name := 'miFilterBuilder';
TPopupMenu(AMenu).Images.AddImage(FormMain.ImageListExtend, 44); //添加图标图像
FMenuItem.ImageIndex := TPopupMenu(AMenu).Images.Count - 1; //指定图标序号
FMenuItem.Caption := '过滤管理器';
FMenuItem.OnClick := Self.miFilterBuilderClick;
TPopupMenu(AMenu).Items.Add(FMenuItem);

//---------------------
FMenuItem := TMenuItem.Create(Self);
FMenuItem.Caption := '-';
TPopupMenu(AMenu).Items.Add(FMenuItem);

//导出
FMenuItem := TMenuItem.Create(Self);
FMenuItem.Name := 'miExport';
TPopupMenu(AMenu).Images.AddImage(FormMain.ImageListExtend, 37);
FMenuItem.ImageIndex := TPopupMenu(AMenu).Images.Count - 1;
FMenuItem.Caption := '导出(&E)';
FMenuItem.OnClick := Self.miExportClick;
TPopupMenu(AMenu).Items.Add(FMenuItem);

//打印
FMenuItem := TMenuItem.Create(Self);
FMenuItem.Name := 'miPrint';
FMenuItem.Caption := '打印(&P)';
TPopupMenu(AMenu).Images.AddImage(FormMain.ImageListExtend, 14);
FMenuItem.ImageIndex := TPopupMenu(AMenu).Images.Count - 1;
FMenuItem.OnClick := Self.miPrintClick;
TPopupMenu(AMenu).Items.Add(FMenuItem);
end;
end;

procedure TFormItemList.miExportClick(Sender: TObject);
var
FileName, FileExt, msg: String;
begin
if Self.aqyQuery.IsEmpty then
begin
msg := '没有导出数据...';
Application.MessageBox(PChar(msg), PChar(Application.Title),
MB_OK or MB_IconWarning);
Exit;
end;

Self.SaveDialogExport.Filter := 'Excel文件 (*.xls)|*.xls|XML文件 (*.xml)|*.xml'
+ '|文本文件 (*.txt)|*.txt|网页文件 (*.html)|*.html';
Self.SaveDialogExport.Title := '导出为';

if not Self.SaveDialogExport.Execute then
Exit;

FileName := Self.SaveDialogExport.FileName;
FileExt := LowerCase(ExtractFileExt(FileName));
if FileExt = '.xls' then
ExportGrid4ToExcel(FileName, Self.cxGrid1)
else if FileExt = '.xml' then
ExportGrid4ToXML(FileName, Self.cxGrid1)
else if FileExt = '.txt' then
ExportGrid4ToText(FileName, Self.cxGrid1)
else if FileExt = '.html' then
ExportGrid4ToHTML(FileName, Self.cxGrid1)
else
begin
msg := '不支持的导出文件类型...';
Application.MessageBox(PChar(msg), PChar(Application.Title),
MB_OK or MB_IconError);
Exit;
end;

msg := '导出完成...';
Application.MessageBox(PChar(msg), PChar(Application.Title),
MB_OK or MB_IconInformation);
end;

procedure TFormItemList.miPrintClick(Sender: TObject);
begin
//打印
Self.dxComponentPrinter.Preview(True, Self.dxComponentPrinterLink1);
end;

procedure TFormItemList.cxGridPopupMenuPopup(ASenderMenu: TComponent;
AHitTest: TcxCustomGridHitTest; X, Y: Integer; var AllowPopup: Boolean);
begin
if GetHitTypeByHitCode(AHitTest.HitTestCode) = gvhtColumnHeader then //右击列标题时
begin
//if tvResult.DataController.Groups.GroupingItemCount > 0 then
if tvResult.GroupedColumnCount > 0 then //有分组时显示
begin
TMenuItem(Self.FindComponent('miLineForGroup')).Visible := True;
TMenuItem(Self.FindComponent('miExpandAllGroup')).Visible := True;
TMenuItem(Self.FindComponent('miCollapseAllGroup')).Visible := True;
end
else
begin
TMenuItem(Self.FindComponent('miLineForGroup')).Visible := False;
TMenuItem(Self.FindComponent('miExpandAllGroup')).Visible := False;
TMenuItem(Self.FindComponent('miCollapseAllGroup')).Visible := False;
end;
end;
end;

procedure TFormItemList.miFilterBuilderClick(Sender: TObject);
begin
//过滤管理器
//弹出Filter Builder Dialog对话框
tvResult.Filtering.RunCustomizeDialog;
end;

procedure TFormItemList.miCustomFilterClick(Sender: TObject);
var
AHitTest: TcxCustomGridHitTest;
begin
//自定义过滤
//弹出Custom Filter Dialog对话框
AHitTest := cxGridPopupMenu.HitTest;
if GetHitTypeByHitCode(AHitTest.HitTestCode) = gvhtColumnHeader then //获得右击的列
tvResult.Filtering.RunCustomizeDialog(TcxGridColumnHeaderHitTest(AHitTest).Column);
end;

procedure TFormItemList.miFilterPanelClick(Sender: TObject);
var
mi: TMenuItem;
begin
//隐藏/显示过滤面板
mi := TMenuItem(Sender);
mi.Checked := True;
if mi.Name = 'miFilterPanelAlways' then
tvResult.Filtering.Visible := fvAlways
else if mi.Name = 'miFilterPanelNerver' then
tvResult.Filtering.Visible := fvNever
else
tvResult.Filtering.Visible := fvNonEmpty;
end;

procedure TFormItemList.miExpandAllGroupClick(Sender: TObject);
begin
//展开所有组
tvResult.DataController.Groups.FullExpand;
end;

procedure TFormItemList.miCollapseAllGroupClick(Sender: TObject);
begin
//收缩所有组
tvResult.DataController.Groups.FullCollapse;
end;

=========

技巧三 按条件计算合计值

在Footer的第一列显示[合计:]
加一个Summary项,Column设为Grid的第一列,Kind设为skNone
在该Summary项的OnGetText事件中,输入:
procedure TFormExpense.tvExpenseTcxGridDBDataControllerTcxDataSummaryFooterSummaryItems2GetText(
Sender: TcxDataSummaryItem; const AValue: Variant; AIsFooter: Boolean;
var AText: String);
begin
AText := '合计:';
end;

按条件汇总:
在TableView的DataController->Summary->FooterSummary->OnSummary事件中,输入:
procedure TFormExpense.tvExpenseDataControllerSummaryFooterSummaryItemsSummary(
ASender: TcxDataSummaryItems; Arguments: TcxSummaryEventArguments;
var OutArguments: TcxSummaryEventOutArguments);
begin
//得到字段名 TcxDBDataSummaryItem(Arguments.SummaryItem).FieldName;
if (ASender.DataController.Values[Arguments.RecordIndex, tvExpenseLevel.Index] > 1) //只统计Level列=1的值
and (TcxDBDataSummaryItem(Arguments.SummaryItem).Kind = skSum) then
OutArguments.Value := 0; //Level > 1的统计值设为0
end;
=========

技巧四:根据某列的值设定其它列的可编辑性

procedure TFormUser.tvUserEditing(Sender: TcxCustomGridTableView;
AItem: TcxCustomGridTableItem; var AAllow: Boolean);
begin
//如果第三列值为True,则第4列不能修改
if (tvUser.Controller.FocusedRecord.Values[2] = True) and (AItem.Index = 4) then
AAllow := False
else
AAllow := True;
end;
============

技巧五:保存/恢复Grid布局

//恢复布局
IniFileName := ExtractFilePath(Application.ExeName) + 'Layout/' + Self.Name + '.ini';
if FileExists(IniFileName) then
Self.tvResult.RestoreFromIniFile(IniFileName) //从布局文件中恢复
else
begin
Self.tvResult.BeginUpdate;
for i := 0 to Self.tvResult.ItemCount - 1 do
Self.tvResult.Items[i].ApplyBestFit; //调整为最佳宽度
Self.tvResult.EndUpdate;
end;

//保存布局
IniFileName := ExtractFilePath(Application.ExeName) + 'Layout/' + Self.Name + '.ini';
if not DirectoryExists(ExtractFileDir(IniFileName)) then
CreateDir(ExtractFileDir(IniFileName));
Self.tvResult.StoreToIniFile(IniFileName); //保存为布局文件
================

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

在主从TableView中根据主TableView得到对应的从TableView
var
ADetailDC: TcxGridDataController;
AView: TcxCustomGridTableView;
begin
with cxGrid1DBTableView1.DataController do
ADetailDC := TcxGridDataController(GetDetailDataController(FocusedRecordIndex, 0));
AView := ADetailDC.GridView;
end;

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

定位在第一行并显示内置编辑器

cxDBVerticalGrid1.FocusedRow := cxDBVerticalGrid1.Rows[0];
cxDBVerticalGrid1.ShowEdit;

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

隐藏 "<No data to display>" 字符串

该文本存储在scxGridNoDataInfoText资源字符串,可以将该资源字符串的内容设为空
来隐藏该文本。

uses cxClasses, cxGridStrs;
...
cxSetResourceString(@scxGridNoDataInfoText, '');

//如果"<No data to display>" 字符串已经显示,需要调用:
<View>.LayoutChanged;

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

删除应用过滤后的行

var
I: Integer;
begin
with <GridView> do
for I := 0 to ViewData.RecordCount - 1 do
begin
ViewData.Records[0].Focused := True;
DataController.DataSet.Delete;
end;

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

根据单元的值设置样式

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];

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

动态生成BandedView

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;
==============================

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

当底层数据集为空时显示一条空记录

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;

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

在当前View插入记录

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。

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

激活内置编辑控件

1) <aView>.Controller.EditingController.ShowEdit(<aColumn>);
2) <aView>.Controller.EditingController.StartEditShowingTimer(<aColumn>);
3) <aView>.Controller.EditingItem := <aColumn>;
4) <aColumn>.Editing := True;

隐藏内置编辑控件
<aView>.Controller.EditingController.HideEdit(True);

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

移除一个分组列

<aColumn>.GroupIndex := -1;
<aColumn>.Visible := True;

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

保存修改到数据库

procedure <aForm>.FormClose(Sender: TObject; var Action: TCloseAction);
begin
if (<aGrid>.FocusedView <> nil) and (<aGrid>.FocusedView.DataController.EditState <> []) then
<aGrid>.FocusedView.DataController.Post;
end;

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

设置内置右键菜单

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;

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

得到选中记录的值

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;

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

在GridMode禁用内置的右键Footer菜单

uses cxGridStdPopupMenu;

procedure cxGridPopupMenuOnPopup(...)
begin
if (ASenderMenu is TcxGridStdFooterMenu) and
<GridView>.DataController.DataModeController.GridMode then
AllowPopup := False;
end;

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

主从表任何时候只能展开一个组

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;

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

动态创建层次(Level)和视图(View)

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;
=====================

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

获得Group Footer合计行对应的记录

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;

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

访问过滤之后的记录

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;

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

获得单元的Font

cxGrid1DBTableView1.ViewInfo.RecordsViewInfo.Items[1].GetCellViewInfoByItem(
cxGrid1DBTableView1Company).EditViewInfo.Font;

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

根据Level名称找到Level对象

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;

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

指定Filter Builder打开/保存过滤文件的默认路径

uses
..., cxFilterControlDialog;

procedure TForm.GridView1FilterControlDialogShow(
Sender: TObject);
begin
TfmFilterControlDialog(Sender).OpenDialog.InitialDir := 'D:/'
end;

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

保存/恢复带汇总行的布局

<TableView>.StoreToIniFile('c:/Grid.ini', True, [gsoUseSummary]);
<GridView>.RestoreFromIniFile(<inifilename>,True,False {or True, optional},[gsoUseSummary]);

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

取消过滤时移到第一行

uses
cxCustomData;

procedure TYour_Form.AViewDataControllerFilterChanged(Sender: TObject);
var
Filter: TcxDataFilterCriteria;
begin
with Sender as TcxDataFilterCriteria do
if IsEmpty then
DataController.FocusedRowIndex := 0;
end;

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

排序后移到第一行

可以设置DataController.Options.FocusTopRowAfterSorting := True,也可以使用如下的代码:

uses
cxCustomData;

procedure TYour_Form.Your_ViewDataControllerSortingChanged(Sender: TObject);
begin
TcxCustomDataController(Sender).FocusedRowIndex := 0;
end;

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

判断当前行是否第一行或最后一行

可以使用DataController的IsBOF, IsEOF方法,或者:
<AView>.Controller.Controller.FocusedRow.IsFirst
<AView>.Controller.Controller.FocusedRow.IsLast

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

根据指定值查找记录

DataController提供了好几个方法来得到指定值对应的RecordIndex
对于Bound View可以使用FindRecordIndexByKeyValue方法

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

编辑和显示Blob字段

该字段的Properties设置为BlobEdit,并将BlobPaintStyle 属性设为 bpsText

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

得到可见行数

<View>.ViewInfo.VisibleRecordCount

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

保存后的行设置为当前行

const
CM_SETFOCUSEDRECORD = WM_USER + 1002;

type
TForm1 = class(TForm)
cxGrid1DBTableView1: TcxGridDBTableView;
cxGrid1Level1: TcxGridLevel;
cxGrid1: TcxGrid;
dxMemData1: TdxMemData;
dxMemData1Field1: TStringField;
dxMemData1Field2: TIntegerField;
DataSource1: TDataSource;
cxGrid1DBTableView1RecId: TcxGridDBColumn;
cxGrid1DBTableView1Field1: TcxGridDBColumn;
cxGrid1DBTableView1Field2: TcxGridDBColumn;
Timer1: TTimer;
CheckBox1: TCheckBox;
procedure Timer1Timer(Sender: TObject);
procedure dxMemData1AfterPost(DataSet: TDataSet);
procedure CheckBox1Click(Sender: TObject);
private
procedure CMSetFocusedRecord(var Msg: TMessage); message CM_SETFOCUSEDRECORD;
public
{ Public declarations }
end;

var
Form1: TForm1;
FocusedIdx: Integer;

implementation

{$R *.dfm}

procedure TForm1.Timer1Timer(Sender: TObject);
begin
dxMemData1.AppendRecord(['', IntToStr(Random(1000)), Random(1000)]);
end;

procedure TForm1.dxMemData1AfterPost(DataSet: TDataSet);
begin
PostMessage(Handle, CM_SETFOCUSEDRECORD, Integer(cxGrid1DBTableView1), MakeLParam(cxGrid1DBTableView1.Controller.FocusedRowIndex, cxGrid1DBTableView1.Controller.TopRowIndex));
end;

procedure TForm1.CMSetFocusedRecord(var Msg: TMessage);
begin
TcxGridDBTableView(msg.WParam).Controller.FocusedRowIndex := Msg.LParamLo;
TcxGridDBTableView(msg.WParam).Controller.TopRowIndex := Msg.LParamHi;
end;

procedure TForm1.CheckBox1Click(Sender: TObject);
begin
Timer1.Enabled := TCheckBox(Sender).Checked;
end;

end.

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

删除记录并获得焦点

procedure TForm1.BtnDeleteClick(Sender: TObject);
var
FocusedRow, TopRow: Integer;
View: TcxGridTableView;
DataController: TcxGridDataController;
begin
View := cxGrid1.FocusedView as TcxGridTableView;
DataController := View.DataController;

// Remember the top row (the vertical scrollbar position)
TopRow := View.Controller.TopRowIndex;
// Remember the focused row(!) index
FocusedRow := DataController.FocusedRowIndex;

DataController.DeleteFocused;

// After deletion the same row must be focused,
// although it will correspond to a different data record
DataController.FocusedRowIndex := FocusedRow;
// Restore the top row
View.Controller.TopRowIndex := TopRow;
end;
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