Saner(?) listbox navigation.

diff --git a/listbox.c b/listbox.c
index 65d88972f9d9d39e8902e13e8d70ca55ec9fef4c..23e8f1fe374c1635c4fd62275ffb88692016c9c6 100644 (file)
--- a/listbox.c
+++ b/listbox.c
@@ -37,6 +37,7 @@ struct listbox {
 static void listboxDraw(newtComponent co);
 static void listboxDestroy(newtComponent co);
 static struct eventResult listboxEvent(newtComponent co, struct event ev);
+static void newtListboxRealSetCurrent(newtComponent co);
 
 static struct componentOps listboxOps = {
     listboxDraw,
@@ -89,7 +90,8 @@ newtComponent newtListbox(int left, int top, int height, int flags) {
     return co;
 }
 
-void newtListboxSetCurrent(newtComponent co, int num) {
+void newtListboxSetCurrent(newtComponent co, int num)
+{
     struct listbox * li = co->data;
     if (num >= li->numItems)
        li->currItem = li->numItems - 1;
@@ -106,13 +108,19 @@ void newtListboxSetCurrent(newtComponent co, int num) {
        li->startShowItem = li->numItems - co->height;
     if(li->startShowItem < 0)
        li->startShowItem = 0;
+    newtListboxRealSetCurrent(co);
+}
+
+static void
+newtListboxRealSetCurrent(newtComponent co)
+{
+    struct listbox * li = co->data;
     if(li->sb)
        newtScrollbarSet(li->sb, li->currItem + 1, li->numItems);
     listboxDraw(co);
     if(co->callback) co->callback(co, co->callbackData);
 }
 
-
 void newtListboxSetWidth(newtComponent co , int width) {
     struct listbox * li = co->data;
     
@@ -383,11 +391,13 @@ static struct eventResult listboxEvent(newtComponent co, struct event ev) {
 
        switch(ev.u.key) {
          case NEWT_KEY_ENTER:
-           if(li-> flags & NEWT_FLAG_RETURNEXIT)
+           if(li->numItems <= 0) break;
+           if(li->flags & NEWT_FLAG_RETURNEXIT)
                er.result = ER_EXITFORM;
            break;
 
          case NEWT_KEY_UP:
+           if(li->numItems <= 0) break;
            if(li->currItem > 0) {
                li->currItem--;
                if(li->currItem < li->startShowItem)
@@ -401,6 +411,7 @@ static struct eventResult listboxEvent(newtComponent co, struct event ev) {
            break;
 
          case NEWT_KEY_DOWN:
+           if(li->numItems <= 0) break;
            if(li->currItem < li->numItems - 1) {
                li->currItem++;
                if(li->currItem > (li->startShowItem + co->height - 1)) {
@@ -417,21 +428,42 @@ static struct eventResult listboxEvent(newtComponent co, struct event ev) {
            break;
 
          case NEWT_KEY_PGUP:
-           newtListboxSetCurrent(co, li->currItem - co->height + 1);
+           if(li->numItems <= 0) break;
+           li->startShowItem -= co->height - 1;
+           if(li->startShowItem < 0)
+               li->startShowItem = 0;
+           li->currItem -= co->height - 1;
+           if(li->currItem < 0)
+               li->currItem = 0;
+           newtListboxRealSetCurrent(co);
            er.result = ER_SWALLOWED;
            break;
 
          case NEWT_KEY_PGDN:
-           newtListboxSetCurrent(co, li->currItem + co->height - 1);
+           if(li->numItems <= 0) break;
+           li->startShowItem += co->height;
+           if(li->startShowItem > (li->numItems - co->height)) {
+               li->startShowItem = li->numItems - co->height;
+           }
+           li->currItem += co->height;
+           if(li->currItem > li->numItems) {
+               li->currItem = li->numItems - 1;
+           }
+           newtListboxRealSetCurrent(co);
            er.result = ER_SWALLOWED;
            break;
 
          case NEWT_KEY_HOME:
+           if(li->numItems <= 0) break;
            newtListboxSetCurrent(co, 0);
            er.result = ER_SWALLOWED;
            break;
 
          case NEWT_KEY_END:
+           if(li->numItems <= 0) break;
+           li->currItem = li->numItems - 1;
+           li->startShowItem = li->numItems - co->height - 1;
+           newtListboxRealSetCurrent(co);
            newtListboxSetCurrent(co, li->numItems - 1);
            er.result = ER_SWALLOWED;
            break;