cdc ecards

How to implement dual Buffering The implementation program is provided first, and then explained again, also in ondraw (CDC * PDC: CDC memdc; // define a display device objectCbitmap membitmap; // defines a bitmap object. // Create a memory display device compatible with Screen DisplayMemdc. createcompatibledc (null );// No drawing yet, because there is no place to draw ^_^// A bitmap compatible with scre

Introduction Removing flicker from an MFC application is well-covered territory. you can find the topic addressed in books, and on-line. however, the techniques presented are somewhat complicated and are usually difficult to add to an existing application. one often-presented technique is called double buffering. double Buffering allows the new screen to be drawn in off-screen memory, and then the completed screen is bit-blited back onto the physical screen. This article presents a class calledC

, and then find the "wm_timer" message, which is the timer message, click " Well, the preparation for the message handler is done, and we're going to start building the class. Specification code, easy to maintain, easy to read, the teacher said you understand:)) Here we build two simple classes on the line, one is the clock class Cclock, one is the needle class (hour, minute, seconds) Cneedle, in the solution view we right-click "header File", add-a class to create these two classes Once you'v

3. Create a drawing tool and select INTO DCWith the canvas, we have to have a paintbrush brush to draw. With GDI objects such as Hpen, Hbrush, and so on in Windows, MFC encapsulates GDI objects nicely, providing classes that encapsulate GDI objects, such as CPen, CBrush, CFont, CBitmap, and CPalette, These classes are derived classes of the GDI object class CGdiObject.Usually first create a brush (brush), and then call the CDC::SelectObject function t

= Def_text_frame_color, bool BShowFrame = False) ; Set hint void settooltips (LPCTSTR psztips); Sets the mouse shape void Setcursortype (Hcursor hcursor); Set font size and type void setfonttype (int fontsize, CString fonttype); Protected:afx_msg BOOL OnEraseBkgnd (cdc* PDC); afx_msg void OnMouseMove (UINT nflags, CPoint point); afx_msg void OnLButtonDown (UINT nflags, CPoint point); afx_msg void OnLButtonUp (UINT nflags, CPoint Point); afx_ms

, and current font.Pen and brush are independent GDI objects. You can use the SelectObject () function of the CDC member function to select DC. Objects in the same operation method include font, bitmap, palette, and region ).About SelectObject (): After a GDI object is created, SelectObject () receives the pointer of this object. The returned value is the same type of object pointer of the DC (usually used to restore the DC ).Windows also pre-defines

IBM provides comprehensive and industry-leading data warehousing and business analysis solutions, including information integration tools InformationServer, real-time and incremental data replication tools InfoSphereCDC, and data warehousing solutions InfosphereWarehouse; business analysis tools CognosBI and a series of business analysis applications. IBM provides comprehensive and industry-leading data warehousing and business analysis solutions, including Information Server, InfoSphere

using the code and constraint files above. Then click on synthesize-xst to synthesize the whole project again.2. Select the top-level module name Led_top, then right-click the new source option and select the second Chipscope Definition and Connection file option in the Popup New Source wizard interface. and take the name chipscope_led (name can be taken casually), and then click Next3. Click Next to click Finish in the popup dialog box.4, Finish Click after completion, and so on for a period o

I. paletteOn a computer that uses a 256-color graphics card, each program allows a total of 256 colors. However, apart from the 20 static colors reserved by the operating system, the other 236 colors allow each application to decide on its own. So we have a palette. Applications running on such computers must select the main colors they need into the color palette of the video card for better display. To use the color palette, we first need to know the type of the computer graphics card to deter

of the MFC Dialog Box program. The dialog box can be changed to an elliptical form: Bool ctestdlg: oninitdialog (){Cdialog: oninitdialog ();...Crgn RGN;RGN. createellipticrgn (0, 0, 200,100 );Setjavaswrgn (RGN, true );} Figure 1 elliptical form 　　Iv. Create a "region" using the plotting Path Method" The process for creating a "region" using this method is as follows: The first step is to draw the shape of the form to be created.　 Some member functions in the

maintenance of the log table needs to be done by the business System program in code.6. System Log Analysis methodThis method can judge the changing data by analyzing the log of the database itself. Relational plow the database system will store all DML operations in the log file for the database backup and restore functions. ETL Halo extraction process through the analysis of the database log, extract the relevant source table after a certain time after the DML operation information, you can k

transmitted from the dialog box, but the customer zone coordinates were used when the canvas was created for drawing. Then the two coordinates are unified, and the problem of blinking is solved. In fact, I have a better understanding of Dual-cache. Next I will post the code of Dual-Cache implementation in my program:Cpaintdc DC (this); // device context for painting On the Internet, we can see that everyone else is using the cmemdc class. As a result, I want to study the content in this area.

onpreparedc (CDC * PDC, cprintinfo * pinfo = NULL) to cchildview ); Void onpreparedc (CDC * PDC, cprintinfo * pinfo ){Crect rect; // Set the loing mode to lometric (0.1mm) and the upper right to the growth direction.PDC-> setmapmode (mm_lometric ); // Set the coordinate origin to the center of the customer ZoneGetclientrect (rect );PDC-> setviewportorg (rect. Width ()/2, rect. Height ()/2 );}Responds to th

program. The dialog box can be changed to an elliptical form: BOOL CTestDlg::OnInitDialog(){CDialog::OnInitDialog();...CRgn rgn;rgn. CreateEllipticRgn(0,0,200,100);SetWindowRgn(rgn,TRUE);} Figure 1 elliptical form IV,Create a "region" using the plotting Path Method" The process for creating a "region" using this method is as follows:The first step is to draw the shape of the form to be created.Some member functions in the CDC class are used in this s

business system and update the maintenance Log table contents when the business data changes, asWhen ETL is loaded, the data is determined by reading the log table data and how to load it.Advantages: No need to modify the business system table structure, the source data extraction clear, faster. Can increase the number of dataLoad.Disadvantages: Log form maintenance needs to be completed by the business system, the business system business operating procedures to be modified, record dayLog info

use the ReleaseDC (PDC); Release the resource, otherwise it will cause a memory leak because GetDC (); The function is assigned some resources that are associated in the memory that the PDC points to, and if ReleaseDC is not called, when the PDC is out of scope, Just the PDC this 32-bit pointer variable (which can also be said to be an integer variable) of memory is freed up, and the memory that the PDC points to has no chance of being freed. Here also reflects a principle of MFC, get to need r

. They work together to provide a mobile Java platform. These two specifications are deployments and profiles. Configuration and profile specifications put forward a considerable number of technical terms, which we will discuss below. Configuration By abstracting the configuration, J2EE processes a large number of hardware functions of different mobile devices. J2_configuration defines virtual machines and low-level APIs available for specific devices, and provides corresponding develo

* *** Add the DLG. h header file: // Add the paint brush and dot variable array to the project: public: cpen m_pen [5]; cpoint m_point [5]; public: void drawline (CDC * PDC ); void drawpolyline (CDC * PDC); void drawpolygon (CDC * PDC); void drawrect (CDC * PDC); void drawroundrect (

designed his first computer ear 1103. But it wasn't long before era was acquired. Clay found that the new company was far behind his own goal-developing the first-stream supercomputer. Finally, Clay chose to leave. In 1957, clay and several other era colleagues resigned and founded the CDC. At the beginning of the design of CDC 1604, Clay's most important innovation in the electronics industry was the adv

drawing speed being too slow or the display graphics being too complex. In fact, this is not true. The influence of the display speed of the drawing on the flashing is not fundamental. For example, in ondraw (CDC * PDC), write as follows: PDC-> moveTo (0, 0 );PDC-> lineto (100,100 ); This drawing process should be very simple and fast, but it will still flash when pulling the window changes. In fact, in principle, the more complex the process of draw