Difficulties in self-painting buttons

 

Recently, I am studying button self-painting. The main difficulties of Button self-painting are as follows:

1. if you want to achieve a slightly more beautiful effect, I think these statuses must be considered: move the mouse, press the mouse, jump the mouse, move the mouse away. then you can process it accordingly. here we will mainly discuss how to capture these events: first, the mouse clicks and the mouse pops up the event, these two events are relatively simple, windows and we have already written these two response messages (we only need to reload them ). one is onlbuttonup and the other is onlbuttondown .. we can set a flag when the mouse is pressed or popped up. in fact, we can judge again in drawitem. (This item can be seen below) followed by mouse entry and mouse removal of the message. you don't think we can reload the onmousemove and onmouseleave messages. in fact, these two types of messages are "special" (because Windows does not directly process them for us). We need to use a Windows function (trackmouseevent) for judgment and processing. the approximate processing is as follows: we add the following code in the onmousemove response function:

// Bhighlight indicates the variable: indicates whether the mouse is on the button.

If (! Bhighlight)

{

Bhighlight = true;

Trackmouseevent TM;

TM. cbsize = sizeof (trackmouseevent );

TM. dwflags = tme_leave;

TM. dwhovertime = 0;

TM. hwndtrack = m_hwnd;

: Trackmouseevent (& TM );

}

// Button re-painting

Invalidaterect (null, true );

Then, we installed a similar mouse exit function: onmouseleave.

Now let's add the message response of this function:

Void clinkbutton: onmouseleave (wparam, lparam)

{

If (bhighlight)

{

// Redraw button

Bhighlight = false;

}

// Pay attention to this statement. If we do not refresh the interface, the interface may not be able to process the message with the mouse removed.

Invalidaterect (null, true );

}

After the two types of messages are added, we also need to do some initialization work to match wm_mouseleave and onmouseleave. Also, we need to use the following two functions: trackmouseevent, which must include such a declaration:

Extern "C" winuserapi bool winapi trackmouseevent (lptrackmouseevent lpeventtrack);. If not, the compiler does not know the trackmouseevent function.

For details about the trackmouseevent struct, refer to another blog.

Blog: http://blog.csdn.net/yuanweihuayan/article/details/6831248

2. Several different states are defined, which correspond to the first four states.

Here we mainly discuss how to obtain the system color.

◆ Color_3dhighlight and color_graytext are two colors for disable.

◆ Color_3dshadow and color_3dhilight are two colors for mouse pressing.

Here you can refer to the getsystemcolor function.

DWORD getsyscolor (INT nindex );
Description
Determines the color of the display object in the specified Windows
Return Value
Long: Specifies the RGB color of the object.
Parameter table
Parameters			Type and description
Nindex			Long, a constant that indicates a specific windows Display object, as shown in the following table
Windows Object constant table
Constant Definition	Windows objects	Constant Definition		Windows objects
Color_activeborder	Border of the activity window	Color_activecaption		Title of the activity window
Color_appworkspace	MDI desktop background	Color_background		Windows Desktop
Color_btnface	Button	Color_btnhighlight		3D highlight area of the button
Color_btnshadow	3D shadow of buttons	Color_btntext		Button text
Color_captiontext	Text in the window title	Color_graytext		Gray text; zero if jitter technology is used
Color_highlight	Selected project background	Color_highlighttext		Selected project text
Color_inactiveborder	Border of the inactive window	Color_inactivecaption		Title of the inactive window
Color_inactivecaptiontext	Text in the inactive window	Color_menu		Menu
Color_menutext	Menu body	Color_scrollbar		Scroll bar
Color_window	Window background	Color_windowframe		Window Frame
Color_windowtext	Window body	Color_3ddkshadow		3D Deep shadow *
Color_3dface	Front color of a 3D shadow object *	Color_3dhilight		3D highlight color (Win95)
Color_3dlight	Light Color of 3D shadow objects *	Color_infobk		Background Color of the tooltip *
Color_infotext	Text color of the tooltip *
*: The constant with "*" is not supported by NT 3.51.

3. Some explanations about drawitem:

See http://blog.csdn.net/yuanweihuayan/article/details/6817631 for details

The key is the following struct: drawitemstruct, which is a frequently used member.

Itemstate: indicates the current state. macros and operations starting with ODS _ are required.

Rcitem: the widget size.

HDC: You can use it to obtain the CDC of the current control.

There are also several common member functions of CDC:

Draw3drect: used to draw 3D buttons.

Drawfocusrect: draws a rectangle with focus.

For specific usage, refer to msdn.

Today, I will summarize some of these ideas. I will continue to do better later ....