Setting dialog box background picture 3 kinds of

WM_PAINT adding Message handler functions

void Cdialog6::onpaint ()

{

CPAINTDC DC (this);//device context for painting

CRect rect;

GetClientRect (&rect);

CDC Dcmem;

Dcmem.createcompatibledc (&DC);

CBitmap Bmpbackground;

Bmpbackground.loadbitmap (IDB_BITMAP2); Idb_bitmap is your own figure corresponding to the ID BITMAP BITMAP;

Bmpbackground.getbitmap (&BITMAP); CBitmap *pbmpold=dcmem.selectobject (&bmpbackground); dc. StretchBlt (0,0,rect. Width (), Rect. Height (), &dcmem,0,0,bitmap.bmwidth,bitmap.bmheight,srccopy);

Cdialog::onpaint () for painting messages

}

Method One:

StretchBlt in the OnPaint

In particular: Comment out cdialog::onpaint () or put it to the end (why?). ), and add the decal code

2. void Cqqqqqdlg::onpaint ()
4. {
6. if (Isiconic ())
8. {
10. CPaintDC DC (this); //device context for painting
14. SendMessage (Wm_iconerasebkgnd, reinterpret_cast<wparam> (DC).  GETSAFEHDC ()), 0);
18. //Center icon in client rectangle
20. int cxicon = GetSystemMetrics (Sm_cxicon);
22. int cyicon = GetSystemMetrics (Sm_cyicon);
24. CRect rect;
26. GetClientRect (&rect);
28. int x = (rect.  Width ()-Cxicon + 1)/2;
30. int y = (rect.  Height ()-Cyicon + 1)/2;
34. //Draw the icon
36. dc. DrawIcon (x, y, M_hicon);
38. }
40. Else
42. {
44. //cdialog::onpaint ();//<span style= "color: #6600cc;"   > Note This sentence, if not annotated, put it to the end, why?
46. </span> //paste background image
48. CPaintDC DC (this);
50. CBitmap bmpbk;
52. BMPBK.LOADBITMAPW (IDB_BITMAP_TEMPBK);
54. //M_BMPBK.LOADBITMAPW (IDB_BMPBK);
56. BITMAP bmpsize;
58. Bmpbk.getbitmap (&bmpsize); //Get background image size
62. CRect rect;
64. GetClientRect (&rect); //Get customer area size
68. CDC Dcmem;
70. Dcmem.createcompatibledc (&DC);
72. Dcmem.selectobject (&BMPBK);
74. dc. StretchBlt (0,0,rect. Width (), Rect. Height (), &dcmem,0,0,bmpsize.bmwidth,bmpsize.bmheight,srccopy); //Stretch or compress the background image to the customer area
76. //Paste background image
78. }
80. }

The following results are performed:

Method Two:

StretchBlt in the OnEraseBkgnd

This is: Comment out the return cdialog::onerasebkgnd (PDC) and return true directly (why not return this to return true?). ), the code is as follows:

2. BOOL cqqqqqdlg::onerasebkgnd (cdc* PDC)
4. {
6. //Todo:add your message handler code here and/or call default
8. //Paste background image
10. CBitmap bmpbk;
12. BMPBK.LOADBITMAPW (IDB_BITMAP_TEMPBK);
14. //M_BMPBK.LOADBITMAPW (IDB_BMPBK);
16. BITMAP bmpsize;
18. Bmpbk.getbitmap (&bmpsize); //Get background image size
22. CRect rect;
24. GetClientRect (&rect); //Get customer area size
28. CDC Dcmem;
30. Dcmem.createcompatibledc (PDC);
32. Dcmem.selectobject (&BMPBK);
34. Pdc->stretchblt (0,0,rect. Width (), Rect. Height (), &dcmem,0,0,bmpsize.bmwidth,bmpsize.bmheight,srccopy); //Stretch or compress the background image to the customer area
36. //Paste background image
38. return true;
40. //return Cdialog::onerasebkgnd (PDC);
42. }

The effect is the same as the method, the picture is not affixed, see.

And here is a very interesting phenomenon, if the OnEraseBkgnd map, in the OnPaint () function does not call the base class OnPaint, that is, comment out Cdialog::onpaint (), the interface is hidden and then displayed then the control is all gone, Only dialog boxes and backgrounds. Such as:

The reason for this is that BeginPaint and EndPaint must be called once in OnPaint and can only be called once. 》

Method Three:

Returns a brush with a background bitmap in OnCtlColor

The specific is:

1. Set a background brush in the header file

1. Public
2. CBrush M_BRUSHBK;

2, add the following sentence in the OnInitDialog

1. Todo:add Extra initialization here
2. CBitmap bmp;
3. Bmp. LoadBitmap (IDB_BITMAP_TEMPBK);
4. M_brushbk.createpatternbrush (&bmp);
5. M_brushbk.createsolidbrush (RGB (0,255,0)); Use solid color as background
6. Bmp. DeleteObject ();

3. Return background brush in OnCtlColor function

2. Hbrush Cxxxxxdlg::onctlcolor (cdc* PDC, cwnd* pWnd, UINT nCtlColor)
4. {
6. hbrush HBR = Cdialog::onctlcolor (PDC, PWnd, nCtlColor);
10. //Todo:change Any attributes of the DC here
14. //Todo:return A different brush if the default is not desired
16. if (pwnd== this) //this represents the current dialog box window
18. {
20. return M_BRUSHBK;
22. }
26. return HBR;
30. }

The effect is as follows:

Note that the IF judgment in this function, the pwnd parameter is critical.

Let's see if there is no such if judgment, directly return to M_BRUSHBK; What will be the result, the code is as follows:

2. Hbrush Cqqqqqdlg::onctlcolor (cdc* PDC, cwnd* pWnd, UINT nCtlColor)
4. {
6. hbrush HBR = Cdialog::onctlcolor (PDC, PWnd, nCtlColor);
10. //Todo:change Any attributes of the DC here
14. //Todo:return A different brush if the default is not desired
18. return M_BRUSHBK;
22. }

As follows:

Look at the picture and talk, do not explain, you understand.

The disadvantage of this approach is the ability to automatically adapt a picture of a stretchblt function to the size of a dialog box (the target rectangle).

Originated from http://www.cnblogs.com/lidabo/archive/2012/07/04/2576172.html

Setting dialog box background picture 3 kinds of