custom icon

[sancelot]

Hi,
Is there a way to setup a custom taskbar icon ?
Regards,
S.Ancelot

[magreenblatt]

Yes, you can do that using platform-specific code. For example, on Windows see here.

[sancelot]

linux version for a jpeg icon

Code: Select all

#include <X11/Xatom.h>
#include "jpeglib.h"
#include  <setjmp.h>
struct ImageData {
       unsigned char *pixels;
       long  width;
       long height;
   };

   ImageData *imageData;


void set_window_icon(cef_window_handle_t window) {
#ifndef WIN32
        Atom net_wm_icon = XInternAtom((Display*) cef_get_xdisplay(),
                        "_NET_WM_ICON", False);
        unsigned long * data = NULL;
        int nelems = 2 + (imageData->width * imageData->height);
        data = (long unsigned int*)malloc(sizeof(unsigned long)*nelems);
        data[0] = imageData->width;
        data[1] = imageData->height;
        for (int i = 0; i < (imageData->width * imageData->height); i++) {
                unsigned long px;
                px = 0xff000000 | ((imageData->pixels[i * 3]) << 16)
                                | (imageData->pixels[i * 3 + 1] << 8)
                                | (imageData->pixels[i * 3 + 2]);
                data[i + 2] = px;
        }
        /// Set Property
        XChangeProperty((Display*) cef_get_xdisplay(), window,
                        net_wm_icon, XA_CARDINAL, 32, PropModeReplace,
                        (unsigned char*) data, nelems);
        free(data);
#endif
}


/*
 * ERROR HANDLING:
 *
 * The JPEG library's standard error handler (jerror.c) is divided into
 * several "methods" which you can override individually.  This lets you
 * adjust the behavior without duplicating a lot of code, which you might
 * have to update with each future release.
 *
 * Our example here shows how to override the "error_exit" method so that
 * control is returned to the library's caller when a fatal error occurs,
 * rather than calling exit() as the standard error_exit method does.
 *
 * We use C's setjmp/longjmp facility to return control.  This means that the
 * routine which calls the JPEG library must first execute a setjmp() call to
 * establish the return point.  We want the replacement error_exit to do a
 * longjmp().  But we need to make the setjmp buffer accessible to the
 * error_exit routine.  To do this, we make a private extension of the
 * standard JPEG error handler object.  (If we were using C++, we'd say we
 * were making a subclass of the regular error handler.)
 *
 * Here's the extended error handler struct:
 */

struct my_error_mgr {
  struct jpeg_error_mgr pub;   /* "public" fields */

  jmp_buf setjmp_buffer;   /* for return to caller */
};

typedef struct my_error_mgr * my_error_ptr;

void my_error_exit (j_common_ptr cinfo)
{
  /* cinfo->err really points to a my_error_mgr struct, so coerce pointer */
  my_error_ptr myerr = (my_error_ptr) cinfo->err;

  /* Always display the message. */
  /* We could postpone this until after returning, if we chose. */
  (*cinfo->err->output_message) (cinfo);

  /* Return control to the setjmp point */
  longjmp(myerr->setjmp_buffer, 1);
}

int read_JPEG_file (const char * filename)
{
  /* This struct contains the JPEG decompression parameters and pointers to
   * working space (which is allocated as needed by the JPEG library).
   */
  struct jpeg_decompress_struct cinfo;
  /* We use our private extension JPEG error handler.
   * Note that this struct must live as long as the main JPEG parameter
   * struct, to avoid dangling-pointer problems.
   */
  struct my_error_mgr jerr;
  /* More stuff */
  FILE * infile;      /* source file */
  JSAMPARRAY buffer;      /* Output row buffer */
  int row_stride;      /* physical row width in output buffer */

  /* In this example we want to open the input file before doing anything else,
   * so that the setjmp() error recovery below can assume the file is open.
   * VERY IMPORTANT: use "b" option to fopen() if you are on a machine that
   * requires it in order to read binary files.
   */

  if ((infile = fopen(filename, "rb")) == NULL) {
    fprintf(stderr, "can't open %s\n", filename);
    return 0;
  }

  /* Step 1: allocate and initialize JPEG decompression object */

  /* We set up the normal JPEG error routines, then override error_exit. */
  cinfo.err = jpeg_std_error(&jerr.pub);
  jerr.pub.error_exit = my_error_exit;
  /* Establish the setjmp return context for my_error_exit to use. */
  if (setjmp(jerr.setjmp_buffer)) {
    /* If we get here, the JPEG code has signaled an error.
     * We need to clean up the JPEG object, close the input file, and return.
     */
    jpeg_destroy_decompress(&cinfo);
    fclose(infile);
    return 0;
  }
  /* Now we can initialize the JPEG decompression object. */
  jpeg_create_decompress(&cinfo);

  /* Step 2: specify data source (eg, a file) */

  jpeg_stdio_src(&cinfo, infile);

  /* Step 3: read file parameters with jpeg_read_header() */

  (void) jpeg_read_header(&cinfo, TRUE);
  /* We can ignore the return value from jpeg_read_header since
   *   (a) suspension is not possible with the stdio data source, and
   *   (b) we passed TRUE to reject a tables-only JPEG file as an error.
   * See libjpeg.txt for more info.
   */

  /* Step 4: set parameters for decompression */

  /* In this example, we don't need to change any of the defaults set by
   * jpeg_read_header(), so we do nothing here.
   */

  /* Step 5: Start decompressor */

  (void) jpeg_start_decompress(&cinfo);
  /* We can ignore the return value since suspension is not possible
   * with the stdio data source.
   */

  /* We may need to do some setup of our own at this point before reading
   * the data.  After jpeg_start_decompress() we have the correct scaled
   * output image dimensions available, as well as the output colormap
   * if we asked for color quantization.
   * In this example, we need to make an output work buffer of the right size.
   */
  /* JSAMPLEs per row in output buffer */
  row_stride = cinfo.output_width * cinfo.output_components;
  /* Make a one-row-high sample array that will go away when done with image */
  buffer = (*cinfo.mem->alloc_sarray)
      ((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);

  imageData = new ImageData;
  imageData->width = cinfo.output_width;
  imageData->height = cinfo.output_height;

  imageData->pixels = new unsigned char [cinfo.output_width * cinfo.output_height * cinfo.output_components];
  long counter = 0;
  /* Step 6: while (scan lines remain to be read) */
  /*           jpeg_read_scanlines(...); */

  /* Here we use the library's state variable cinfo.output_scanline as the
   * loop counter, so that we don't have to keep track ourselves.
   */
  while (cinfo.output_scanline < cinfo.output_height) {
    /* jpeg_read_scanlines expects an array of pointers to scanlines.
     * Here the array is only one element long, but you could ask for
     * more than one scanline at a time if that's more convenient.
     */
    (void) jpeg_read_scanlines(&cinfo, buffer, 1);
    /* Assume put_scanline_someplace wants a pointer and sample count. */
    // store in the image
    memcpy(imageData->pixels+counter, buffer[0], row_stride);
    counter += row_stride;
  }

  /* Step 7: Finish decompression */

  (void) jpeg_finish_decompress(&cinfo);
  /* We can ignore the return value since suspension is not possible
   * with the stdio data source.
   */

  /* Step 8: Release JPEG decompression object */

  /* This is an important step since it will release a good deal of memory. */
  jpeg_destroy_decompress(&cinfo);

  /* After finish_decompress, we can close the input file.
   * Here we postpone it until after no more JPEG errors are possible,
   * so as to simplify the setjmp error logic above.  (Actually, I don't
   * think that jpeg_destroy can do an error exit, but why assume anything...)
   */
  fclose(infile);

  /* At this point you may want to check to see whether any corrupt-data
   * warnings occurred (test whether jerr.pub.num_warnings is nonzero).
   */

  /* And we're done! */
  return 1;
}



I then modified simple_handler.cpp as follow :

Code: Select all

void SimpleHandler::OnAfterCreated(CefRefPtr<CefBrowser> browser) {
  CEF_REQUIRE_UI_THREAD();

  // Add to the list of existing browsers.
  browser_list_.push_back(browser);

  read_JPEG_file ("logo.jpg");
  set_window_icon(browser->GetHost()->GetWindowHandle());
}