[code cpp]
(mousemove事件裡)
(Edit_Form[Page_Code]->DoubleBuffered = true;)

Application->ProcessMessages();
Edit_Form[Page_Code]->Canvas->Pen->Color=clYellow; //筆刷設定
Edit_Form[Page_Code]->Canvas->Pen->Style=psDot;
Edit_Form[Page_Code]->Canvas->Pen->Mode=psClear ;
Edit_Form[Page_Code]->Canvas->Pen->Width=1;
process_part( 0,ARow_all->MMI_Ins_Type); //重畫物件,物件尺寸改變時,內容也必須更新
Edit_Form[Page_Code]->Repaint();
Edit_Form[Page_Code]->Canvas->Rectangle
(ctrl->Left-1,ctrl->Top-1,
ctrl->Left ctrl->Width 1,ctrl->Top ctrl->Height 1); //繪製物件外框虛線
Edit_Form[Page_Code]->Canvas->Brush->Style=bsClear; //BRUSH風格

dx1=ctrl->Left-3;
dx2=dx1 (ctrl->Width)/2;
dx3=dx1 ctrl->Width;
dy1=ctrl->Top-3;
dy2=dy1 (ctrl->Height)/2;
dy3=dy1 ctrl->Height;
RECT rectdor={105,229,111,235}; //八個小方塊的圖案
RECT rx1={ dx1,dy1,dx1 6,dy1 6} ;
RECT rx2={ dx2,dy1,dx2 6,dy1 6} ;
RECT rx3={ dx3,dy1,dx3 6,dy1 6} ;
RECT rx4={ dx1,dy2,dx1 6,dy2 6} ;
RECT rx5={ dx3,dy2,dx3 6,dy2 6} ;
RECT rx6={ dx1,dy3,dx1 6,dy3 6} ;
RECT rx7={ dx2,dy3,dx2 6,dy3 6} ;
RECT rx8={ dx3,dy3,dx3 6,dy3 6} ;
Edit_Form[Page_Code]->Canvas->CopyRect(rx2,Form1->ImageBT->Canvas,rectdor);
Edit_Form[Page_Code]->Canvas->CopyRect(rx3,Form1->ImageBT->Canvas,rectdor);
Edit_Form[Page_Code]->Canvas->CopyRect(rx6,Form1->ImageBT->Canvas,rectdor);
Edit_Form[Page_Code]->Canvas->CopyRect(rx7,Form1->ImageBT->Canvas,rectdor);
Edit_Form[Page_Code]->Canvas->CopyRect(rx8,Form1->ImageBT->Canvas,rectdor);
Edit_Form[Page_Code]->Canvas->CopyRect(rx1,Form1->ImageBT->Canvas,rectdor);
Edit_Form[Page_Code]->Canvas->CopyRect(rx4,Form1->ImageBT->Canvas,rectdor);
Edit_Form[Page_Code]->Canvas->CopyRect(rx5,Form1->ImageBT->Canvas,rectdor);


Application->ProcessMessages();

[/code]

各位兄弟,新年第一帖^^
如題和上面的程式,我拉動一個物件時,那八個小方塊,都會因為重繪物件時,會把小方塊蓋到
這樣一來 當然會有閃動的問題...

有沒有任何方法,可以讓小方塊不會閃?

因為看過別人這樣的東西:拉動時,超級順的,外框 小方塊 物件 完全不閃,而且它的物件,
也是在拉動時 會一直更新的內容的

這問題困擾很久了..各位指點一下,感恩啦~~~

編輯記錄

可以利用一個暫存圖(off-screen), 先將要改變的畫面畫在此圖上,
在用此暫存圖取代顯示用的圖.
相關函式:
// 將畫面 從 off-screen copy 到 畫面
BitBlt(SDIAppForm->MainDrawImage->Canvas->Handle, 0, 0, SDIAppForm->MainDrawImage->Width,
SDIAppForm->MainDrawImage->Height, OffScreen->Canvas->Handle, 0, 0, SRCCOPY);

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