自画TListView带进度条的Item

 

自画 TlistView 带进度条的 Item

TListView的Item条一般是由系统自画的，但电驴就实现了自画，使之看起来很漂亮，我们用DELPHI也可以实现！

 

首先要引用 CommCtrl 单元，这是TListView底层控制单元：

uses

  CommCtrl;

 

// 画状态条

procedure DrawSubItem(LV: TListView; Item: TListItem; SubItem: Integer;

 Prosition: Single; Max, Style: Integer; IsShowProgress: Boolean;

 DrawColor: TColor = $00005B00 ;

 FrameColor: TColor = $00002F00 );

// 获取 SubItem 的区域

  function GetItemRect(LV_Handle, iItem, iSubItem: Integer): TRect;

  var

    Rect: TRect;

  begin

    ListView_GetSubItemRect(LV_Handle, iItem, iSubItem, LVIR_LABEL, @Rect);

    Result := Rect;

  end ;

var

  PaintRect, r: TRect;

 i, iWidth, x, y: integer;

 S: string ;

begin

 try

 

    with lv do

    begin

      //LockPaint := True;

      PaintRect := GetItemRect(LV.Handle, Item.Index, SubItem);

     r := PaintRect;

//      if SubItem = DrawSubItem then

      Begin

        // 这一段是算出百分比

        if Prosition >= Max then

          Prosition := 100

        else

          if Prosition <= 0 then

            Prosition := 0

          else

            Prosition := Round((Prosition / Max) * 100 );

 

        if (Prosition = 0 ) and ( not IsShowProgress) then

        begin

        // 如果是百分比是 0 ，就直接显示空白

          Canvas.FillRect(r);

 

        end

        else

        begin

        // 先直充背景色

          Canvas.FillRect(r);

          Canvas.Brush.Color := Color;

//          Canvas.FillRect(r);

 

        // 画一个外框

          InflateRect(r, - 2 , - 2 );

          Canvas.Brush.Color := FrameColor; //$00002F00;

          Canvas.FrameRect(R);

 

          Canvas.Brush.Color := Color;

          InflateRect(r, - 1 , - 1 );

//          Canvas.FillRect(r);

 

          InflateRect(r, - 1 , - 1 );

        // 根据百分比算出要画的进度条内容宽度

          iWidth := R.Right - Round((R.Right - r.Left) * (( 100 - Prosition) /

            100 ));

          case Style of

            0 : // 进度条类型，实心填充

              begin

                Canvas.Brush.Color := DrawColor;

                r.Right := iWidth;

                Canvas.FillRect(r);

              end ;

            1 : // 进度条类型，竖线填充

              begin

                i := r.Left;

                while i < iWidth do

                begin

                  Canvas.Pen.Color := Color;

                  Canvas.MoveTo(i, r.Top);

                  Canvas.Pen.Color := DrawColor;

                  canvas.LineTo(i, r.Bottom);

                  Inc(i, 3 );

                end ;

              end ;

          end ;

// 画好了进度条后，现在要做的就是显示进度数字了

          Canvas.Brush.Style := bsClear;

          if Prosition = Round(Prosition) then

            S := Format( '%d%%' , [Round(Prosition)])

          else

            S := FormatFloat( '#0.0' , Prosition);

 

          with PaintRect do

          begin

            x := Left + (Right - Left + 1 - Canvas.TextWidth(S)) div 2 ;

            y := Top + (Bottom - Top + 1 - Canvas.TextHeight(S)) div 2 ;

          end ;

          SetBkMode(Canvas.handle, TRANSPARENT);

          Canvas.TextRect(PaintRect, x, y, S);

 

        end ;

// 进度条全部画完，把颜色设置成默认色了

        Canvas.Brush.Color := Color;

 

      end

    end ;

  except

  end ;

end ;

 

 

上面是画进度条的，现在要给 TlistView 处理 Item 重绘的消息，事件是 On CustomDrawItem ， 需要说明的是，如果想要随心所欲的自画 Item ，那么就要全部自己来完成，不再需要系统来处理：

procedure TForm1.ListView1CustomDrawItem(

 Sender: TCustomListView; Item: TListItem; State: TCustomDrawState;

  var DefaultDraw: Boolean);

var

  BoundRect, Rect: TRect;

 i: integer;

 TextFormat: Word;

 LV: TListView;

 

// 这个子过程是用来画 CheckBox 和 ImageList 的

  procedure Draw_CheckBox_ImageList(r: TRect; aCanvas: TCanvas; Checked: Boolean);

  var

    R1: TRect;

    i: integer;

  begin

    if Sender.Checkboxes then

    begin

      aCanvas.Pen.Color := clBlack;

      aCanvas.Pen.Width := 2 ;

      // 画 CheckBox 外框

      aCanvas.Rectangle(r.Left + 2 , r.Top + 2 , r.Left + 14 , r.Bottom - 2 );

      if Checked then

      begin // 画 CheckBox 的勾

        aCanvas.MoveTo(r.Left + 4 , r.Top + 6 );

        aCanvas.LineTo(r.Left + 6 , r.Top + 11 );

        aCanvas.LineTo(r.Left + 11 , r.Top + 5 );

      end ;

      aCanvas.Pen.Width := 1 ;

    end ;

    // 开始画图标

    i := PDownLoadListItem(Item.Data)^.StatsImageIndex;

    if i > - 1 then

    begin

    // 获取图标的 RECT

      if Boolean(ListView_GetSubItemRect(sender.Handle, item.Index, 0 , LVIR_ICON, @R1)) then

      begin

        ImageList_Stats.Draw(LV.Canvas, R1.Left, R1.Top, i);

        if item.ImageIndex > - 1 then

          LV.SmallImages.Draw(LV.Canvas, R1.Right + 2 , R1.Top, item.ImageIndex);

      end ;

 

    end ;

  end ;

begin

  LV := ListView1;

 BoundRect := Item.DisplayRect(drBounds);

 InflateRect(BoundRect, - 1 , 0 );

 

// 这个地方你可以根据自己的要求设置成想要的颜色，实现突出显示

  LV.Canvas.Font.Color := clBtnText;

 

// 查看是否是被选中

  if Item.Selected then

 begin

    if cdsFocused in State then

    begin

      LV.Canvas.Brush.Color := $00ECCCB9 ; // //clHighlight;

    end

    else

    begin

      LV.Canvas.Brush.Color := $00F8ECE5 ; //clSilver;

    end ;

  end

 else

 begin

    if (Item.Index mod 2 ) = 0 then

      LV.Canvas.Brush.Color := clWhite

    else

      LV.Canvas.Brush.Color := $00F2F2F2 ;

  end ;

 

 LV.Canvas.FillRect(BoundRect); // 初始化背景

 

  for i := 0 to LV.Columns.Count - 1 do

 begin

  // 获取 SubItem 的 Rect

    ListView_GetSubItemRect(LV.Handle, Item.Index, i, LVIR_LABEL, @Rect);

    case LV.Columns[i].Alignment of

      taLeftJustify:

        TextFormat := 0 ;

      taRightJustify:

        TextFormat := DT_RIGHT;

      taCenter:

        TextFormat := DT_CENTER;

    end ;

    case i of

      0 : // 画 Caption ， 0 就是表示 Caption ，这不是 Subitems[0]

        begin

// 先画选择框与图标

          Draw_CheckBox_ImageList(BoundRect, LV.Canvas, Item.Checked);

// 再画 Caption 的文字

          InflateRect(Rect, -( 5 + ImageList_Stats.Width), 0 ); // 向后移 3 个像素 , 避免被后面画线框时覆盖

          DrawText(

            LV.Canvas.Handle,

            PCHAR(Item.Caption),

            Length(Item.Caption),

            Rect,

            DT_VCENTER or DT_SINGLELINE or DT_END_ELLIPSIS or TextFormat);

        end ;

      1 ..MaxInt: // 画 Subitems[i]

        begin

          if i - 1 = 2 then // 显示状态条

          begin

// 开始处理进度条了，这个示例是第 3 栏显示进度条，可以自己随便定义

            DrawSubItem(TListView(Sender),

              item,

              i,

              StrToFloatDef(Item.SubItems[i - 1 ], 0 ),

              100 ,

              0 ,

              True,

 // 这里用了一个 Lable 来选颜色，你自己可以使用一个变量来代替

             LableProgressColor.Color, // 进度条外框颜色

              LableProgressColor.Color  // 进度条颜色

);

 

          end

          else

// 画 SubItem 的文字

            if i - 1 <= Item.SubItems.Count - 1 then

              DrawText(

                LV.Canvas.Handle,

                PCHAR(Item.SubItems[i - 1 ]),

                Length(Item.SubItems[i - 1 ]),

                Rect,

                DT_VCENTER or DT_SINGLELINE or DT_END_ELLIPSIS or TextFormat);

 

 

 

        end ;

    end ;

 

  end ;

 

 

 LV.Canvas.Brush.Color := clWhite;

 

  if Item.Selected then // 画选中条外框

  begin

    if cdsFocused in State then // 控件是否处于激活状态

      LV.Canvas.Brush.Color := $00DAA07A // $00E2B598; //clHighlight;

    else

      LV.Canvas.Brush.Color := $00E2B598 ; //$00DAA07A // clHighlight;

    LV.Canvas.FrameRect(BoundRect); //

  end ;

 

 DefaultDraw := False; // 不让系统画了

 

  with Sender.Canvas do

    if Assigned(Font.OnChange) then Font.OnChange(Font);

 

 

 

end ;

function ReDrawItem(HwndLV: HWND; ItemIndex: integer): boolean;
begin
  Result := ListView_RedrawItems(HwndLV, ItemIndex, ItemIndex);
end;

//使用：

item:=ListView1.Selected;

item.subitems[1]:='30';//设置为30%

//然后刷新这个item
ReDrawItem(ListView1.handle,Item.index);

 

不用进度条时的效果图：