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vast improvement on movement of caret due to isolation of cause of problem - TLDR is Chrome detects blank rows line heights as incorrect

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This commit is contained in:
John McLear 2013-09-25 14:57:02 +01:00
parent 3e1e92c100
commit 487f1a969f
1 changed files with 22 additions and 7 deletions
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29
src/static/js/ace2_inner.js
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@ -3793,21 +3793,35 @@ function Ace2Inner(){
}, 200);
}
/* Attempt to apply some sanity to cursor handling in Chrome after a copy / paste event
We have to do this the way we do because rep. doesn't hold the value for keyheld events IE if the user
presses and holds the arrow key */
presses and holds the arrow key .. Sorry if this is ugly, blame Chrome's weird handling of viewports after new content is added*/
if((evt.which == 37 || evt.which == 38 || evt.which == 39 || evt.which == 40) && $.browser.chrome){
var viewport = getViewPortTopBottom();
var myselection = document.getSelection(); // get the current caret selection, can't use rep. here because that only gives us the start position not the current
var caretOffsetTop = myselection.focusNode.parentNode.offsetTop; // get the carets selection offset in px IE 214
var lineHeight = $(myselection.focusNode.parentNode).parent().height(); // get the line height of the caret line
var caretOffsetTop = myselection.focusNode.parentNode.offsetTop || myselection.focusNode.offsetTop; // get the carets selection offset in px IE 214
var lineHeight = $(myselection.focusNode.parentNode).parent("div").height(); // get the line height of the caret line
// top.console.log("offsetTop", myselection.focusNode.parentNode.parentNode.offsetTop);
try {
lineHeight = $(myselection.focusNode).height() // needed for how chrome handles line heights of null objects
// console.log("lineHeight now", lineHeight);
}catch(e){}
var caretOffsetTopBottom = caretOffsetTop + lineHeight;
var visibleLineRange = getVisibleLineRange(); // the visible lines IE 1,10
if(caretOffsetTop){ // sometimes caretOffsetTop bugs out and returns 0, not sure why, possible Chrome bug? Either way if it does we don't wanna mess with it
var caretIsNotVisible = (caretOffsetTop <= viewport.top || caretOffsetTopBottom >= viewport.bottom); // Is the Caret Visible to the user?
// top.console.log(caretOffsetTop, viewport.top, caretOffsetTopBottom, viewport.bottom);
var caretIsNotVisible = (caretOffsetTop < viewport.top || caretOffsetTopBottom >= viewport.bottom); // Is the Caret Visible to the user?
// Expect some weird behavior caretOffsetTopBottom is greater than viewport.bottom on a keypress down
var offsetTopSamePlace = caretOffsetTop == viewport.top; // sometimes moving key left & up leaves the caret at the same point as the viewport.top, technically the caret is visible but it's not fully visible so we should move to it
if(offsetTopSamePlace && (evt.which == 37 || evt.which == 38)){
var newY = caretOffsetTop;
setScrollY(newY);
}
if(caretIsNotVisible){ // is the cursor no longer visible to the user?
// top.console.log("Caret is NOT visible to the user");
// top.console.log(caretOffsetTop,viewport.top,caretOffsetTopBottom,viewport.bottom);
// Oh boy the caret is out of the visible area, I need to scroll the browser window to lineNum.
if(evt.which == 37 || evt.which == 38){ // If left or up arrow
var newY = caretOffsetTop; // That was easy!
@ -3819,10 +3833,11 @@ function Ace2Inner(){
// top.console.log("line #", rep.selStart[0]); // the line our caret is on
// top.console.log("firstvisible", visibleLineRange[0]); // the first visiblel ine
// top.console.log("lastVisible", visibleLineRange[1]); // the last visible line
// top.console.log(rep.selStart[0],visibleLineRange[1],rep.selStart[0], visibleLineRange[0]);
// Holding down arrow after a paste can lose the cursor -- This is the best fix I can find
if(rep.selStart[0] >= visibleLineRange[1] || rep.selStart[0] < visibleLineRange[0] ){ // if we're not at the bottom of the viewport
// top.console.log(viewport, lineHeight, myselection);
// top.console.log("Moving down doc", viewport, lineHeight, myselection);
// is the line in alignment with the bottom of the viewport cause if so we shouldnt be paginating?
// TODO: Make it so chrome doesnt need to redraw the page by only applying this technique if required
var newY = caretOffsetTop;
}else{ // we're at the bottom of the viewport so snap to a "new viewport"