Fix inconsistent updating of KotoButton iconography noticed via KotoExpander in KotoNav.

Turtles all the way down.

src/koto-button.c

@@ -309,6 +309,10 @@ void koto_button_flip(KotoButton * self) {
 }
 
 void koto_button_hide_image(KotoButton * self) {
+	if (!KOTO_IS_BUTTON(self)) { // Not a button
+		return;
+	}
+
 	if (GTK_IS_WIDGET(self->button_pic)) { // Is a widget
 		gtk_widget_hide(self->button_pic);
 	}
@@ -318,6 +322,10 @@ void koto_button_set_badge_text(
 	KotoButton * self,
 	gchar * text
 ) {
+	if (!KOTO_IS_BUTTON(self)) { // Not a button
+		return;
+	}
+
 	if ((text == NULL) || (strcmp(text, "") == 0)) { // If the text is empty
 		self->badge_text = g_strdup("");
 	} else {
@@ -366,6 +374,14 @@ void koto_button_set_icon_name(
 	gchar * icon_name,
 	gboolean for_alt
 ) {
+	if (!KOTO_IS_BUTTON(self)) { // Not a button
+		return;
+	}
+
+	if (!koto_utils_is_string_valid(icon_name)) { // Not a valid icon
+		return;
+	}
+
 	gchar * copied_icon_name = g_strdup(icon_name);
 
 	if (for_alt) { // Is for the alternate icon
@@ -390,12 +406,12 @@ void koto_button_set_icon_name(
 		hide_image = TRUE;
 	}
 
-	if (hide_image) { // Should hide the image
-		if (GTK_IS_PICTURE(self->button_pic)) { // If we already have a button image
+	if (GTK_IS_IMAGE(self->button_pic)) { // If we already have a button image
+		if (hide_image) { // Should hide the image
 			gtk_widget_hide(self->button_pic); // Hide
+		} else { // Should be showing the image
+			gtk_image_set_from_icon_name(GTK_IMAGE(self->button_pic), self->icon_name); // Just update the existing image immediately
 		}
-
-		return;
 	}
 
 	g_object_notify_by_pspec(G_OBJECT(self), for_alt ? btn_props[PROP_ALT_ICON_NAME] : btn_props[PROP_ICON_NAME]);
@@ -405,6 +421,10 @@ void koto_button_set_image_position(
 	KotoButton * self,
 	KotoButtonImagePosition pos
 ) {
+	if (!KOTO_IS_BUTTON(self)) { // Not a button
+		return;
+	}
+
 	if (self->image_position == pos) { // Is a different position that currently
 		return;
 	}
@@ -424,6 +444,10 @@ void koto_button_set_pixbuf_size(
 	KotoButton * self,
 	guint size
 ) {
+	if (!KOTO_IS_BUTTON(self)) {
+		return;
+	}
+
 	if (size == self->pix_size) {
 		return;
 	}
@@ -438,11 +462,15 @@ void koto_button_set_text(
 	KotoButton * self,
 	gchar * text
 ) {
-	if (text == NULL) {
+	if (!KOTO_IS_BUTTON(self)) {
 		return;
 	}
 
-	if (self->text != NULL) { // Text defined
+	if (!koto_utils_is_string_valid(text)) { // Invalid text
+		return;
+	}
+
+	if (koto_utils_is_string_valid(self->text)) { // Text defined
 		g_free(self->text); // Free existing text
 	}
 
@@ -492,7 +520,6 @@ void koto_button_show_image(
 			gtk_box_prepend(GTK_BOX(self), self->button_pic); // Prepend to the box
 		}
 	} else { // From icon name
-
 		if (use_alt && ((self->alt_icon_name == NULL) || (strcmp(self->alt_icon_name, "") == 0))) { // Don't have an alt icon set
 			return;
 		} else if (!use_alt && ((self->icon_name == NULL) || (strcmp(self->icon_name, "") == 0))) { // Don't have icon set
@@ -503,7 +530,7 @@ void koto_button_show_image(
 		gchar * name = use_alt ? self->alt_icon_name : self->icon_name;
 
 		if (GTK_IS_IMAGE(self->button_pic)) {
-			gtk_image_set_from_icon_name(GTK_IMAGE(self->button_pic), name); // Just update the existing iamge
+			gtk_image_set_from_icon_name(GTK_IMAGE(self->button_pic), name); // Just update the existing image
 		} else { // Not an image
 			self->button_pic = gtk_image_new_from_icon_name(name); // Get our new image
 			gtk_box_prepend(GTK_BOX(self), self->button_pic); // Prepend to the box

src/koto-expander.c

@@ -20,6 +20,7 @@
 #include "config/config.h"
 #include "koto-button.h"
 #include "koto-expander.h"
+#include "koto-utils.h"
 
 enum {
 	PROP_EXP_0,
@@ -146,20 +147,9 @@ static void koto_expander_set_property(
 ) {
 	KotoExpander * self = KOTO_EXPANDER(obj);
 
-	if (!GTK_IS_WIDGET(self->header_button)) { // Header Button is not a widget
-		KotoButton * new_button = koto_button_new_with_icon(NULL, "emblem-favorite-symbolic", NULL, KOTO_BUTTON_PIXBUF_SIZE_SMALL);
-
-		if (GTK_IS_WIDGET(new_button)) { // Created our widget successfully
-			self->header_button = new_button;
-			gtk_widget_set_hexpand(GTK_WIDGET(self->header_button), TRUE);
-			gtk_box_prepend(GTK_BOX(self->header), GTK_WIDGET(self->header_button));
-		}
-	}
-
 	switch (prop_id) {
 		case PROP_HEADER_ICON_NAME:
-			g_return_if_fail(GTK_IS_WIDGET(self->header_button));
-			koto_button_set_icon_name(self->header_button, g_strdup(g_value_get_string(val)), FALSE);
+			koto_expander_set_icon_name(self, g_strdup(g_value_get_string(val)));
 			break;
 		case PROP_HEADER_LABEL:
 			g_return_if_fail(GTK_IS_WIDGET(self->header_button));
@@ -193,6 +183,14 @@ static void koto_expander_init(KotoExpander * self) {
 	gtk_revealer_set_reveal_child(GTK_REVEALER(self->revealer), TRUE); // Set to be revealed by default
 	gtk_revealer_set_transition_type(GTK_REVEALER(self->revealer), GTK_REVEALER_TRANSITION_TYPE_SLIDE_DOWN);
 
+	KotoButton * new_button = koto_button_new_with_icon(NULL, "emblem-favorite-symbolic", NULL, KOTO_BUTTON_PIXBUF_SIZE_SMALL);
+
+	if (KOTO_IS_BUTTON(new_button)) { // Created our widget successfully
+		self->header_button = new_button;
+		gtk_widget_set_hexpand(GTK_WIDGET(self->header_button), TRUE);
+		gtk_box_prepend(GTK_BOX(self->header), GTK_WIDGET(self->header_button));
+	}
+
 	self->header_expand_button = koto_button_new_with_icon("", "pan-down-symbolic", "pan-up-symbolic", KOTO_BUTTON_PIXBUF_SIZE_SMALL);
 	gtk_box_append(GTK_BOX(self->header), GTK_WIDGET(self->header_expand_button));
 
@@ -204,6 +202,26 @@ static void koto_expander_init(KotoExpander * self) {
 	koto_button_add_click_handler(self->header_expand_button, KOTO_BUTTON_CLICK_TYPE_PRIMARY, G_CALLBACK(koto_expander_toggle_content), self);
 }
 
+// koto_expander_set_icon_name will set the icon for our inner KotoButton for this Expander
+void koto_expander_set_icon_name(
+	KotoExpander *self,
+	gchar * icon
+) {
+	if (!KOTO_IS_EXPANDER(self)) { // Not a KotoExpander
+		return;
+	}
+
+	if (!koto_utils_is_string_valid(icon)) { // Not a valid string
+		return;
+	}
+
+	if (!KOTO_IS_BUTTON(self->header_button)) { // Don't have a header button for whatever reason
+		return;
+	}
+
+	koto_button_set_icon_name(self->header_button, icon, FALSE);
+}
+
 void koto_expander_set_secondary_button(
 	KotoExpander * self,
 	KotoButton * new_button

src/koto-expander.h

@@ -36,8 +36,8 @@ KotoExpander * koto_expander_new_with_button(
 GtkWidget * koto_expander_get_content(KotoExpander * self);
 
 void koto_expander_set_icon_name(
-	KotoExpander * self,
-	const gchar* in
+	KotoExpander *self,
+	gchar * icon
 );
 
 void koto_expander_set_label(