the compiler failed with error code 128 asp.net THE TEXT VIEW WIDGET in Font

Drawing Data Matrix 2d barcode in Font THE TEXT VIEW WIDGET

Although not used in Listing 7-7, it is possible to remove a tag from an area of text with gtk_text_buffer_remove_tag_by_name(). This function will remove all instances of the tag between the two iterators if they exist. void gtk_text_buffer_remove_tag_by_name (GtkTextBuffer *buffer, const gchar *name, const GtkTextIter *start, const GtkTextIter *end);

Note These functions only remove tags from a certain range of text. If the tag was added to a larger range

of text than the range specified, the tag will be removed for the smaller range, and new bounds will be created on either side of the selection. You can test this with the application in Listing 7-7.

If you have access to the GtkTextTag object, you can remove the tag with gtk_text_buffer_ remove_tag(). It is also possible to remove every tag within a range with gtk_text_buffer_remove_ all_tags().

In some applications, you may want to insert images into a text buffer. This can easily be done with GdkPixbuf objects. In Figure 7-8, two images were inserted into a text buffer as GdkPixbuf objects.

Figure 7-8. GdkPixbuf objects in a text buffer Adding a pixbuf to a GtkTextBuffer is performed in three steps. First, you must create the pixbuf object and retrieve the GtkTextIter where it will be inserted. Then, you can use gtk_text_buffer_insert_pixbuf() to add it to the buffer. Listing 7-8 shows the process of creating a GdkPixbuf object from a file and adding it to a text buffer.

Listing 7-8. Inserting Images into Text Buffers (images.c) #include <gtk/gtk.h> #define IMAGE_UNDO "/path/to/undo.png" #define IMAGE_REDO "/path/to/redo.png" int main (int argc, char *argv[]) { GtkWidget *window, *scrolled_win, *textview; GdkPixbuf *undo, *redo; GtkTextIter line; GtkTextBuffer *buffer; gtk_init (&argc, &argv); window = gtk_window_new (GTK_WINDOW_TOPLEVEL); gtk_window_set_title (GTK_WINDOW (window), "Pixbufs"); gtk_container_set_border_width (GTK_CONTAINER (window), 10); gtk_widget_set_size_request (window, 200, 150); textview = gtk_text_view_new (); buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (textview)); gtk_text_buffer_set_text (buffer, " Undo\n Redo", -1); /* Create two images and insert them into the text buffer. */ undo = gdk_pixbuf_new_from_file (IMAGE_UNDO, NULL); gtk_text_buffer_get_iter_at_line (buffer, &line, 0); gtk_text_buffer_insert_pixbuf (buffer, &line, undo); redo = gdk_pixbuf_new_from_file (IMAGE_REDO, NULL); gtk_text_buffer_get_iter_at_line (buffer, &line, 1); gtk_text_buffer_insert_pixbuf (buffer, &line, redo); scrolled_win = gtk_scrolled_window_new (NULL, NULL); gtk_container_add (GTK_CONTAINER (scrolled_win), textview); gtk_container_add (GTK_CONTAINER (window), scrolled_win); gtk_widget_show_all (window); gtk_main(); return 0; }

Inserting a GdkPixbuf object into a text buffer is done with gtk_text_buffer_insert_pixbuf(). The GdkPixbuf object is inserted at the specified location, which can be any valid text iterator in the buffer. void gtk_text_buffer_insert_pixbuf (GtkTextBuffer *buffer, GtkTextIter *iter, GdkPixbuf *pixbuf); Pixbufs are handled differently by various functions. For example, gtk_text_buffer_ get_slice() will place the 0xFFFC character where a pixbuf is located. However, the 0xFFFC character can occur as an actual character in the buffer, so that is not a reliable indicator of the location of a pixbuf. Another example is gtk_text_buffer_get_text(), which will completely ignore nontextual elements, so there is no way to check for pixbufs within the text using this function. Therefore, if you are using pixbufs in a GtkTextBuffer, it is best to retrieve text from the buffer with gtk_text_buffer_get_slice(). You can then use gtk_text_iter_get_pixbuf() to check whether the 0xFFFC character represents a GdkPixbuf object; it will return NULL if a pixbuf is not found at that location. GdkPixbuf* gtk_text_iter_get_pixbuf (const GtktTextIter *iter);

Inserting widgets into a text buffer is a little more complicated than pixbufs, because you must notify both the text buffer and the text view to embed the widget. You begin by creating a GtkTextChildAnchor object, which will be used to mark the placement of the widget within the GtkTextBuffer. Then, you add the widget to the GtkTextView widget.

Figure 7-9. A child widget inserted into a text buffer Figure 7-9 shows a GtkTextView widget that contains a child GtkButton widget. Listing 7-9 can be used to create this window. When the button is pressed, gtk_main_quit() is called, which terminates the application.