X-Git-Url: https://git.stderr.nl/gitweb?a=blobdiff_plain;f=tests%2Fbarf.c.eventbox;fp=tests%2Fbarf.c.eventbox;h=29eda83d480c5d5a253795b05a0cfdeb5a125daa;hb=a2e82e317a6000511953c2dbc0eb1026c7b245a7;hp=0000000000000000000000000000000000000000;hpb=378e7e222af1027d8c6330f086511fe5f283e376;p=rodin%2Fchimara.git diff --git a/tests/barf.c.eventbox b/tests/barf.c.eventbox new file mode 100644 index 0000000..29eda83 --- /dev/null +++ b/tests/barf.c.eventbox @@ -0,0 +1,246 @@ +/* + * Compile me with: + * gcc -g -O0 -Wall -pthread -o barf barf.c `pkg-config --cflags --libs gtk+-2.0` + */ + +#include +#include + +/* Uncomment to try the other paging method */ +/* #define PAGE_ONLY_UNSEEN 1 */ + +static gulong pager_handler = 0; +static gulong expose_handler = 0; +static gboolean currently_paging = FALSE; + +static gint promptwidth, promptheight; +static PangoLayout *prompt; +static GdkColor red, white; + +static gboolean +quit() +{ + gtk_main_quit(); + return TRUE; +} + +/* Vomit a load of text onto the screen */ +static void +barf(GtkButton *button, GtkTextView *textview) +{ + GtkTextIter end; + GtkTextBuffer *buffer = gtk_text_view_get_buffer(textview); + gtk_text_buffer_get_end_iter(buffer, &end); + + gchar *loremipsum; + g_file_get_contents("loremipsum.txt", &loremipsum, NULL, NULL); + gtk_text_buffer_insert(buffer, &end, loremipsum, -1); + g_free(loremipsum); + + gtk_widget_grab_focus(GTK_WIDGET(textview)); +} + +/* Helper function: move the pager to the last visible position in the buffer, + and return the distance between the pager and the end of the buffer in buffer + coordinates */ +static gint +move_pager_and_get_scroll_distance(GtkTextView *textview) +{ + GdkRectangle pagerpos, endpos, visiblerect; + GtkTextIter oldpager, newpager, end; + GtkTextBuffer *buffer = gtk_text_view_get_buffer(textview); + GtkTextMark *pager = gtk_text_buffer_get_mark(buffer, "pager_position"); + + /* Get an iter at the lower right corner of the visible part of the buffer */ + gtk_text_view_get_visible_rect(textview, &visiblerect); + gtk_text_view_get_iter_at_location(textview, &newpager, visiblerect.x + visiblerect.width, visiblerect.y + visiblerect.height); + gtk_text_buffer_get_iter_at_mark(buffer, &oldpager, pager); + +#ifdef PAGE_ONLY_UNSEEN + if(gtk_text_iter_compare(&oldpager, &newpager) < 0) + gtk_text_buffer_move_mark(buffer, pager, &newpager); +#else + gtk_text_buffer_move_mark(buffer, pager, &newpager); +#endif + + /* Get the buffer coordinates of the pager and the end iter */ + gtk_text_buffer_get_end_iter(buffer, &end); + gtk_text_buffer_get_iter_at_mark(buffer, &newpager, pager); + gtk_text_view_get_iter_location(textview, &newpager, &pagerpos); + gtk_text_view_get_iter_location(textview, &end, &endpos); + + //g_printerr("View height = %d\n", visiblerect.height); + //g_printerr("End - Pager = %d\n", endpos.y - pagerpos.y); + + return endpos.y - pagerpos.y; +} + +/* Helper function: turn on paging for this textview */ +static void +start_paging(GtkWidget *eventbox) +{ + currently_paging = TRUE; + g_signal_handler_unblock(eventbox, expose_handler); + g_signal_handler_unblock(eventbox, pager_handler); +} + +/* Helper function: turn off paging for this textview */ +static void +stop_paging(GtkWidget *eventbox) +{ + currently_paging = FALSE; + g_signal_handler_block(eventbox, expose_handler); + g_signal_handler_block(eventbox, pager_handler); +} + +/* Update the pager position after new text is inserted in the buffer */ +static void +after_insert(GtkTextBuffer *buffer, GtkTextIter *location, gchar *text, gint len, GtkTextView *textview) +{ + while(gtk_events_pending()) + gtk_main_iteration(); + + /* Move the pager to the last visible character in the buffer */ + gint scroll_distance = move_pager_and_get_scroll_distance(textview); + + if(scroll_distance > 0 && !currently_paging) { + GtkWidget *eventbox = gtk_widget_get_parent( gtk_widget_get_parent(GTK_WIDGET(textview)) ); + start_paging(eventbox); + } +} + +static void +adjustment_changed(GtkAdjustment *adjustment, GtkTextView *textview) +{ + while(gtk_events_pending()) + gtk_main_iteration(); + + /* Move the pager, etc. */ + gint scroll_distance = move_pager_and_get_scroll_distance(textview); + + GtkWidget *eventbox = gtk_widget_get_parent( gtk_widget_get_parent(GTK_WIDGET(textview)) ); + if(scroll_distance > 0 && !currently_paging) + start_paging(eventbox); + else if(scroll_distance == 0 && currently_paging) + stop_paging(eventbox); + + /* Refresh the widget so that any extra "more" prompts disappear */ + gtk_widget_queue_draw(GTK_WIDGET(eventbox)); +} + +/* Handle key press events in the textview while paging is active */ +static gboolean +pager_wait(GtkTextView *eventbox, GdkEventKey *event, GtkTextBuffer *buffer) +{ + /*** ALTERNATIVE, POSSIBLY INFERIOR, METHOD OF SCROLLING *** + GtkTextMark *pagermark = gtk_text_buffer_get_mark(buffer, "pager_position"); + gtk_text_view_scroll_to_mark(textview, pagermark, 0.0, TRUE, 0.0, 0.0); + */ + + GtkWidget *scrolledwindow = gtk_bin_get_child(GTK_BIN(eventbox)); + GtkAdjustment *adj = gtk_scrolled_window_get_vadjustment(GTK_SCROLLED_WINDOW(scrolledwindow)); + gdouble step_increment, page_size, upper, lower, value; + g_object_get(adj, + "page-size", &page_size, + "step-increment", &step_increment, + "upper", &upper, + "lower", &lower, + "value", &value, + NULL); + + switch (event->keyval) { + case GDK_space: case GDK_KP_Space: case GDK_Page_Down: case GDK_KP_Page_Down: + gtk_adjustment_set_value(adj, CLAMP(value + page_size, lower, upper - page_size)); + return TRUE; + case GDK_Page_Up: case GDK_KP_Page_Up: + gtk_adjustment_set_value(adj, CLAMP(value - page_size, lower, upper - page_size)); + return TRUE; + case GDK_Return: case GDK_KP_Enter: + gtk_adjustment_set_value(adj, CLAMP(value + step_increment, lower, upper - page_size)); + return TRUE; + /* don't handle "up" and "down", they're used for input history */ + } + + return FALSE; /* if the key wasn't handled here, pass it to other handlers */ +} + +/* Draw the "more" prompt on top of the buffer, after the regular expose event has run */ +static gboolean +expose_prompt(GtkEventBox *eventbox, GdkEventExpose *event) +{ + GdkGC *context = gdk_gc_new(GDK_DRAWABLE(event->window)); + + gint winx, winy, winwidth, winheight; + gdk_window_get_position(event->window, &winx, &winy); + gdk_drawable_get_size(GDK_DRAWABLE(event->window), &winwidth, &winheight); + + gdk_draw_layout_with_colors(event->window, context, + winx + winwidth - promptwidth, + //winy + winheight - promptheight, + winy - 5, + prompt, &white, &red); + + return FALSE; /* Propagate event further */ +} + +int +main(int argc, char **argv) +{ + gtk_init(&argc, &argv); + + /* Construct the widgets */ + GtkWidget *window = gtk_window_new(GTK_WINDOW_TOPLEVEL); + gtk_widget_set_size_request(window, 400, 400); + GtkWidget *button = gtk_button_new_with_label("Barf"); + GtkWidget *eventbox = gtk_event_box_new(); +// gtk_event_box_set_above_child( GTK_EVENT_BOX(eventbox), TRUE ); + GTK_WIDGET_SET_FLAGS(eventbox, GTK_APP_PAINTABLE); + GtkWidget *scrolledwindow = gtk_scrolled_window_new(NULL, NULL); + GtkWidget *textview = gtk_text_view_new(); + gtk_text_view_set_wrap_mode(GTK_TEXT_VIEW(textview), GTK_WRAP_WORD_CHAR); + gtk_text_view_set_editable(GTK_TEXT_VIEW(textview), FALSE); + GtkWidget *vbox = gtk_vbox_new(FALSE, 6); + + /* Pack all the widgets into their containers */ + gtk_container_add(GTK_CONTAINER(scrolledwindow), textview); + gtk_container_add(GTK_CONTAINER(eventbox), scrolledwindow); + gtk_box_pack_start(GTK_BOX(vbox), button, FALSE, FALSE, 0); + gtk_box_pack_start(GTK_BOX(vbox), eventbox, TRUE, TRUE, 0); + gtk_container_add(GTK_CONTAINER(window), vbox); + gtk_widget_show_all(window); + + /* Set up the textview widget to receive exposure events, must be done after widget has been shown */ + gdk_window_set_events(gtk_widget_get_window(eventbox), GDK_EXPOSURE_MASK); + + /* Create the 'more' prompt */ + prompt = gtk_widget_create_pango_layout(GTK_WIDGET(textview), "More"); + pango_layout_get_pixel_size(prompt, &promptwidth, &promptheight); + gdk_color_parse("red", &red); + gdk_color_parse("white", &white); + + /* Connect paging signals */ + GtkTextBuffer *buffer = gtk_text_view_get_buffer(GTK_TEXT_VIEW(textview)); + g_signal_connect_after(buffer, "insert-text", G_CALLBACK(after_insert), textview); + GtkAdjustment *adj = gtk_scrolled_window_get_vadjustment(GTK_SCROLLED_WINDOW(scrolledwindow)); + g_signal_connect_after(adj, "value-changed", G_CALLBACK(adjustment_changed), textview); + pager_handler = g_signal_connect(eventbox, "key-press-event", G_CALLBACK(pager_wait), buffer); + g_signal_handler_block(eventbox, pager_handler); + expose_handler = g_signal_connect(eventbox, "expose-event", G_CALLBACK(expose_prompt), NULL); + g_signal_handler_block(eventbox, expose_handler); + + /* Create the pager position mark; it stands for the last character in the buffer + that has been on-screen */ + GtkTextIter end; + gtk_text_buffer_get_end_iter(buffer, &end); + GtkTextMark *pagermark = gtk_text_buffer_create_mark(buffer, "pager_position", &end, TRUE); + gtk_text_mark_set_visible(pagermark, TRUE); + + /* Connect "regular program" signals */ + g_signal_connect(window, "delete-event", G_CALLBACK(quit), NULL); + g_signal_connect(button, "clicked", G_CALLBACK(barf), textview); + + gtk_main(); + + g_object_unref(prompt); + return 0; +}