请教如何用Xlib显示图片（JPG，等）__display_the_window_int_screen_num_

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请教如何用Xlib显示图片（JPG，等）

来源: 互联网发布时间：2016-04-05

本文导语: 我现在有一段代码，老显示doesn't contain a valid bitmap.代码如下： /* * draw-pixmap.c - demonstrate drawing of a pixmap on screen, after * reading its contents from a bitmap file. */ #include #include /*...

我现在有一段代码，老显示doesn't contain a valid bitmap.代码如下：
/*
* draw-pixmap.c - demonstrate drawing of a pixmap on screen, after
*                    reading its contents from a bitmap file.
*/

#include
#include  /* BitmapOpenFailed, etc. */
#include
#include  /* getenv(), etc. */
#include  /* sleep(), etc.  */

/*
* function: create_simple_window. Creates a window with a white background
*          in the given size.
* input:    display, size of the window (in pixels), and location of the window
*          (in pixels).
* output:  the window's ID.
* notes:    window is created with a black border, 2 pixels wide.
*          the window is automatically mapped after its creation.
*/
Window
create_simple_window(Display* display, int width, int height, int x, int y)
{
  int screen_num = DefaultScreen(display);
  int win_border_width = 0;
  Window win;

  /* create a simple window, as a direct child of the screen's */
  /* root window. Use the screen's black and white colors as  */
  /* the foreground and background colors of the window,      */
  /* respectively. Place the new window's top-left corner at  */
  /* the given 'x,y' coordinates.                              */
  win = XCreateSimpleWindow(display, RootWindow(display, screen_num),
                            x, y, width, height, win_border_width,
                            BlackPixel(display, screen_num),
                            WhitePixel(display, screen_num));

  /* make the window actually appear on the screen. */
  XMapWindow(display, win);

  /* flush all pending requests to the X server. */
  XFlush(display);

  return win;
}

GC
create_gc(Display* display, Window win, int reverse_video)
{
  GC gc; /* handle of newly created GC.  */
  unsigned long valuemask = 0; /* which values in 'values' to  */
/* check when creating the GC.  */
  XGCValues values; /* initial values for the GC.  */
  unsigned int line_width = 2; /* line width for the GC.      */
  int line_style = LineSolid; /* style for lines drawing and  */
  int cap_style = CapButt; /* style of the line's edje and */
  int join_style = JoinBevel; /*  joined lines. */
  int screen_num = DefaultScreen(display);

  gc = XCreateGC(display, win, valuemask, &values);
  if (gc