misc scrollable positioning.

lib/widget.js

@@ -2606,15 +2606,12 @@ Box.prototype._getCoords = function(get) {
     // this.parent.lpos.yi - which was saved after it's render() **with the
     // childBase subtracted!!!!*** This means nested elements within
     // a scrollable box are screwy unless we do this.
+    // We only do this when `get` is true, because that gets this.parent.lpos.
+    // If it's false, the parent's position is calculated on the spot.
     var cb = el.childBase;
     if (get) {
-      var el_ = this;
-      // Do we need to get every parent?
-      while (el_ = el_.parent) {
-        if (el_ === el) break;
-        yi += el_.lpos.cb;
-        yl += el_.lpos.cb;
-      }
+      yi += this.parent.lpos.cb;
+      yl += this.parent.lpos.cb;
     }
 
     ryi = yi - el._getTop(get) - el.itop;
@@ -3202,7 +3199,7 @@ ScrollableBox.prototype.scrollTo = function(offset) {
   return this.scroll(offset - (this.childBase + this.childOffset));
 };
 
-ScrollableBox.prototype.scroll = function(offset) {
+ScrollableBox.prototype.scroll = function(offset, always) {
   if (!this.scrollable) return;
 
   // Handle scrolling.
@@ -3213,7 +3210,7 @@ ScrollableBox.prototype.scroll = function(offset) {
     , t
     , b;
 
-  if (this.alwaysScroll) {
+  if (this.alwaysScroll || always) {
     // Semi-workaround
     this.childOffset = offset > 0
       ? visible - 1 + offset
@@ -4033,7 +4030,6 @@ Textbox.prototype.render = function() {
   // setContent is necessary to clear the area in case
   // .shrink is being used and the new content is smaller.
   // Could technically optimize this.
-  if (!this._getCoords(true)) return;
   if (this.secret) {
     this.setContent('');
     return this._render();
@@ -4090,7 +4086,7 @@ Textarea.prototype.updateCursor = function() {
     return;
   }
 
-  var lpos = this.getCoords();
+  var lpos = this._getCoords();
   if (!lpos) return;
 
   var last = this._clines[this._clines.length-1]
@@ -4646,7 +4642,6 @@ Checkbox.prototype.type = 'checkbox';
 
 Checkbox.prototype._render = Checkbox.prototype.render;
 Checkbox.prototype.render = function() {
-  //if (!this._getCoords(true)) return;
   if (this.type === 'radio-button') {
     this.setContent('(' + (this.checked ? '*' : ' ') + ') ' + this.text);
   } else {
@@ -5223,7 +5218,6 @@ Listbar.prototype.setItems = function(commands) {
 
 Listbar.prototype._render = Listbar.prototype.render;
 Listbar.prototype.render = function() {
-  if (!this._getCoords(true)) return;
   var self = this
     , drawn = 0;
 

test/widget-form.js

@@ -30,12 +30,12 @@ form.on('submit', function(data) {
 });
 
 form.key('d', function() {
-  form.scroll(1);
+  form.scroll(1, true);
   screen.render();
 });
 
 form.key('u', function() {
-  form.scroll(-1);
+  form.scroll(-1, true);
   screen.render();
 });
 
@@ -143,6 +143,46 @@ submit.on('press', function() {
   form.submit();
 });
 
+var box1 = blessed.box({
+  parent: form,
+  left: 1,
+  top: 10,
+  height: 10,
+  width: 10,
+  content: 'one',
+  bg: 'cyan'
+});
+
+var box2 = blessed.box({
+  parent: box1,
+  left: 1,
+  top: 2,
+  height: 8,
+  width: 9,
+  content: 'two',
+  bg: 'magenta'
+});
+
+var box3 = blessed.box({
+  parent: box2,
+  left: 1,
+  top: 2,
+  height: 6,
+  width: 8,
+  content: 'three',
+  bg: 'yellow'
+});
+
+var box4 = blessed.box({
+  parent: box3,
+  left: 1,
+  top: 2,
+  height: 4,
+  width: 7,
+  content: 'four',
+  bg: 'blue'
+});
+
 var output = blessed.scrollabletext({
   parent: screen,
   mouse: true,