XE StringGrid应用（G1属性触发G2）

unit UnitMain;

interface

uses
  System.SysUtils, System.Types, System.UITypes, System.Classes, System.Variants,
  FMX.Types, FMX.Controls, FMX.Forms, FMX.Graphics, FMX.Dialogs, System.Rtti,
  FMX.StdCtrls, FMX.Grid, FMX.Layouts, FMX.Controls.Presentation, FMX.Edit;

type
  TForm8 = class(TForm)
    Edit1: TEdit;
    G1: TStringGrid;
    G2: TStringGrid;
    StringColumn1: TStringColumn;
    StringColumn2: TStringColumn;
    Button1: TButton;
    Button2: TButton;
    procedure FormActivate(Sender: TObject);
    procedure G1SelectCell(Sender: TObject; const ACol, ARow: Integer;
      var CanSelect: Boolean);
    procedure G2SelectCell(Sender: TObject; const ACol, ARow: Integer;
      var CanSelect: Boolean);
    procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean);
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    FRow2: Integer;
    FRow1: Integer;
    { Private declarations }
    procedure ShowG1();　　// 显示表1
    procedure ShowG2();　　// 显示表2数据
    procedure Item();　　　// 显示Edit等数据　
    procedure Save();　　　// 保存数据
    procedure SetRow1(const Value: Integer);
    procedure SetRow2(const Value: Integer);
  public
    { Public declarations }
    property Row1 : Integer read FRow1 write SetRow1; // 表1属性，OnSelectCell属性触发，改变时do something
    property Row2 : Integer read FRow2 write SetRow2; // 表1属性，OnSelectCell属性触发，改变时do something
  end;

var
  Form8: TForm8;

implementation

{$R *.fmx}

procedure TForm8.Button1Click(Sender: TObject);
begin
  G2.RowCount:=G2.RowCount+1;　　　　　　// 动态改变G2的Row
  G2.Cells[0,G2.RowCount-1]:='aa';
end;

procedure TForm8.Button2Click(Sender: TObject);
begin
  Edit1.Text := FROW2.ToString ;
end;

procedure TForm8.FormActivate(Sender: TObject);
begin
  if(Tag=0) then begin
    Tag:=1;

    FRow1:=-1;
    FRow2:=-1;

    ShowG1();
    if(g1.RowCount>0) then G1.SelectCell(0,0); // 初始化时，选中G1的第一行
  end;
end;

procedure TForm8.ShowG1;
var
  ss: TStringList;
  i: Integer;
begin
  ss:=TStringList.Create;
  ss.LoadFromFile('c:/g1.txt');
  G1.RowCount:=ss.Count;
  for i:=0 to ss.Count-1 do G1.Cells[0,i]:=ss[i];
  ss.Free;
end;

procedure TForm8.ShowG2;
var
  ss: TStringList;
  i: Integer;
begin
  ss:=TStringList.Create;
  ss.LoadFromFile('c:/g2'+FRow1.ToString+'.txt');
  G2.RowCount:=ss.Count;
  for i:=0 to ss.Count-1 do G2.Cells[0,i]:=ss[i];
  ss.Free;

  FRow2:=-1;
  if(G2.RowCount>0) then begin
    Row2:=0;
    G2.SelectCell(0,0);
  end;
end;

procedure TForm8.Item;
begin
  Edit1.Text:=G2.Cells[0,Row2];
end;

procedure TForm8.Save;
var
  ss:TStringList;
  i:Integer;
begin
  if(FRow2>=0) and (FRow2<=G2.RowCount-1) then begin
    if(Edit1.Text<>G2.Cells[0,FRow2]) then begin
      G2.Cells[0,FRow2]:=Edit1.Text;

      ss:=TStringList.Create;
      for i:=0 to G2.RowCount-1 do ss.Add(G2.Cells[0,i]);
      ss.SaveToFile('c:/g2'+FRow1.ToString+'.txt');

      ss.Clear();
      for i:=0 to G1.RowCount-1 do ss.Add(G1.Cells[0,i]);
      ss.SaveToFile('c:/g1.txt');
      ss.Free;
    end;
  end;
end;

procedure TForm8.SetRow1(const Value: Integer);
begin
  if(Value<>FRow1) then begin
    Save();
    FRow1 := Value;
    G1.SelectCell(0,Value);
    ShowG2();
  end;
end;

procedure TForm8.SetRow2(const Value: Integer);
begin
  if(Value<>FRow2) then begin
    Save();
    FRow2 := Value;
    Item();
  end;
end;

procedure TForm8.FormCloseQuery(Sender: TObject; var CanClose: Boolean);
begin
  Save();
  CanClose:=True;
end;

procedure TForm8.G1SelectCell(Sender: TObject; const ACol, ARow: Integer;
  var CanSelect: Boolean);
begin
  //  鼠标点击空白地方的时候，会触发该事件，而ARow的值超出范围
  CanSelect:=False;
  if(ARow>=0) and (ARow<=G1.RowCount-1) then begin
    if(Row1<>ARow) then Row1:=ARow;
    CanSelect:=True;
  end;
end;

procedure TForm8.G2SelectCell(Sender: TObject; const ACol, ARow: Integer;
  var CanSelect: Boolean);
begin
  CanSelect:=False;
  if(ARow>=0) and (ARow<=G2.RowCount-1) then begin
    if(Row2<>ARow) then Row2:=ARow;
    CanSelect:=True;
  end;
end;

end.

XE中StringGrid控件还是有很多bug的，在OnSelectCell事件里，鼠标滑过也会触发，若要用ShowMessage或弹出模态窗体，Grid重新聚焦时，会频繁的触发。

在鼠标滑过没有行的Index位置时，也会触发OnSelectCell事件，会出现Index超界，报错。

所以每次都必须保证Grid里有数据，(ARow>=0) and (ARow<=G2.RowCount-1)