I have a handson table with 300+. It renders quickly. However, if I update one column in all rows like so:
function() {
console.trace("Start", new Date());
$scope.myData.forEach(function(elem, idx) {
elem.properties.myCol = Math.random();
if (idx % 100 == 0) console.trace("Tick", new Date());
});
console.trace("End", new Date());
};
The loop executes in less than a second, but the browser tab locks up and the page does not update for over a minute. Is there some way I can disable handsontable from reading updates to the array and then triggering a manual redraw? Is there any other way to speed this up?
After updating the handsontable data you can use
$('#yourTable').handsontable("render");
To re-render the handsontable manually after any updates to the data. And set observeChanges:false (It is false by default) while creating handsontable to disable automatic re-rendering by handsontable.
The option that was slowing down rendering was columnSorting: true,. Removing this fixed the issue.
Related
What is the best way to set a saved grid state after the angular-slickgrid has already been created? The Grid State/Presets - Wiki explains setting the saved state on load by setting the gridOptions.presets. In my case, I would like to update the grid state when the underlying saved state has changed in local storage (perhaps saved from another instantiation of the app), and apply the state to the current slickgrid. If I update the gridOptions.presets, is there a method I can call to force the grid to update with the new presets?
Please note that I'm the author of Angular-Slickgrid.
The answer is No it's called Presets for a reason, it only works when creating the grid...but you can still do it with a few method calls. So if you really wanted to use the Grid State then you'll have to save it yourself and then reload the entire grid after applying all previous State. The Grid State that can be applied dynamically are the Filters and Sorting which you can see in Example 4 and Example 25 (with a button click or a dropdown selection like the last example). I did later add a method to change the columns as well and that one is demoed under this Slickgrid-Universal Example 11, in fact that demo will show you exactly the way you want to do it, you can follow the code here.
for a short code sample, you'll need to get the angularGrid instance from (onAngularGridCreated) and then use it to dynamically change the grid. It shows you all the options, you can skip any of them if you don't need or want to change that option.
angularGridReady(angularGrid: AngularGridInstance) {
this.angularGrid = angularGrid;
}
// the `selectedView` should be the result of your Grid State
changeGridView(selectedView: GridState) {
if (selectedView) {
const columns = selectedView?.columns ?? [];
const filters = selectedView?.filters ?? [];
const sorters = selectedView?.sorters ?? [];
this.angularGrid.filterService.updateFilters(filters as CurrentFilter[]);
this.angularGrid.sortService.updateSorting(sorters as CurrentSorter[]);
this.angularGrid.gridStateService.changeColumnsArrangement(columns);
// if you have a frozen grid (pinning)
this.angularGrid.gridService.setPinning(pinning);
} else {
// to reset the grid
this.angularGrid.filterService.clearFilters();
this.angularGrid.sortService.clearSorting(); this.angularGrid.gridStateService.changeColumnsArrangement([...this.columnDefinitions].map(col => ({ columnId: `${col.id}` })));
// if you have a frozen grid (pinning)
this.angularGrid.gridService.clearPinning();
}
// you might want to scroll back to top of the grid if filters are changed
this.angularGrid.slickGrid.scrollColumnIntoView(0);
}
You might not need to re-render the grid but in case the grid UI doesn't show correctly, you could force a re-render of the grid by invalidating all its rows
this.angularGrid.slickGrid.invalidate();
HandsonTable is not rendering all rows - it loads only part of all rows. But when I do Ctrl+A and paste into Excel I see all the rows. Why is Handsontable not displaying all the rows?
<hot-table col-headers="true" row-headers="true" datarows="data" context-menu width="1080">
<hot-column ng-repeat="column in columns" data="{{column.data}}"></hot-column>
</hot-table>
To render all rows, just set renderAllRows: true
The current answer does not answer the original question.
Handsontable does not render all cells at once because it is designed to be efficient for very large data sets. It does this using virtual rendering, dynamically modifying the DOM to include only the cells at the scroll position.
The rows virtual rendering can be disabled by setting renderAllRows: true, as described in the docs: "If typed true then virtual rendering mechanism for handsontable will be disabled." Although it will then not be as efficient for large data sets.
You can also change the number of pre-rendered rows and columns instead of rendering them all. From the performance tips,
You can explicitly specify the number of rows and columns to be rendered outside of the visible part of the table. In some cases you can achieve better results by setting a lower number (as less elements get rendered), but sometimes setting a larger number may also work well (as less operations are being made on each scroll event). Tweaking these settings and finding the sweet spot may improve the feeling of your Handsontable implementation.
This is done by setting viewportRowRenderingOffset and viewportColumnRenderingOffset in the handsontable options. These are by default set to auto which lets handsontable try to find the best value, but may be provided an integer value (e.g. viewportRowRenderingOffset: 70, viewportColumnRenderingOffset: 70).
I had the same problem (using HandsOnTable 6.2.1 and the old AngularJS) and customers would start complaining about not being sure if they were at the end of the table or not.
I was able to create two buttons linked to the functions 'scrollToBeginning' and 'scrollToEnd'. This way the user is sure to be at the last line. Three things specific about my answer:
I expose the functions to the DOM using $scope;
I have an object 'goToLine' holding 3 properties (scrollingToEnd: boolean, row: number, col: number), it is used in other functions not posted here;
I have a list of ID referencing HandsOnTable objects stored in $scope.hots.
Here is my raw solution, feel free to adapt / enhance:
$scope.stopScrollingToEnd = function () {
$scope.goToLine.scrollingToEnd = false;
};
$scope.scrollToBeginning = function (goToLine) {
$scope.stopScrollingToEnd();
const hot = $scope.hots[goToLine.id];
hot.scrollViewportTo(0, 0);
};
/**
* Scroll to the end of the List Element.
* We need this functionality because of a bug in HandsOnTable related to its Virtualization process.
* In some cases (complex table), when manually scrolling, the max row is wrong, hence causing major confusion for the user.
* #param {*} goToLine
* #returns
*/
$scope.scrollToEnd = function (goToLine) {
// We scroll to the first line before going to the last to avoid the bug and being sure we get to the last line
$scope.scrollToBeginning(goToLine);
const hot = $scope.hots[goToLine.id];
var numberOfRows = hot.countRows();
// This variable is used to repeat the scrollViewportTo command.
// It is built using the length of `numberOfRows`.
var repeat = numberOfRows ? 1 * Math.ceil(Math.log10(numberOfRows + 1)) : 1;
// Used in other goTo function to avoid conflict.
$scope.goToLine.scrollingToEnd = true;
// FIXME : not supposed to call scrollViewportTo several times... => fixed in recent versions of HandsOnTable ?
for (let n = 0; n < repeat; n++) {
if (!$scope.goToLine.scrollingToEnd) {
return;
}
setTimeout(function () {
if (!$scope.goToLine.scrollingToEnd) {
return;
}
hot.scrollViewportTo(numberOfRows - 1, 0);
}, 500);
}
};
So what I'm trying to accomplish is when the grid is fully loaded, I loop over a certain column that contains checkboxes. Depending on the value of the checkbox I should be able to disable it.
Problem is that I can't access the html element that's there. Am i doing something wrong or overlooking something?
What i've tried:
loadComplete: function() {
// Fetch all the ID's of the rows
var rows = $("#table").getDataIDs();
// Loop over the rows
if(rows.length != 0){
for(i=0; i < rows.length; i++) {
// Get the data so we test on a certain condition
var row = $("#table").jqGrid("getRowData", rows[i]);
if (row.gridCheckbox == 1) {
//disable the element
row.prop("disabled", "disabled");
}
}
}
}
It's important to understand that changing one element on the page follow in the most cases to web browser reflow: validation whether some property (position for example) need be changed in all other elements on the page. If you do changes in the loop then your JavaScript code can be really slow.
Thus it's strictly recommended to reduce the number of changes of the DOM. Especially to reduce the number of changes jqGrid provides rowattr, cellattr and custom formatters. If you need for example to set disabled attribute on some rows then you should now do this in loadComplete, but to use rowattr instead to inform jqGrid that some additional attributes (disabled="disabled") should be set on some rows. jqGrid collect first the string representation of the whole table body and it use one assignment of innerHTML to fill the whole body of the grid in one DOM operation. It improves essentially the performance. See code example in the old answer.
Is there any way i can hide HOT columns from javascript?
The requirement is such that the column to hide will come as a parameter in javascript and based on that the respective column will show hide accordingly.
The HOT has rowHeaders and colHeaders and the data with 20 columns.
Please advise.
OUTDATED SOLUTION
Ok I founnd a possible solution. I tested it out on my own system but it's actually quite simple.
You should be using a customRenderer in your columns option. Read up about this if you aren't already. The idea is that you're giving each cell its own renderer. In this custom function, you can do something like this:
var colsToHide = [3,4,6]; // hide the fourth, fifth, and seventh columns
function getCustomRenderer() {
return function(instance, td, row, col, prop, value, cellProperties) {
if (colsToHide.indexOf(col) > -1) {
td.hidden = true;
} else {
td.hidden = false;
}
}
}
What this renderer does is hide the cells that the var colsToHide specify. All you do now is add a DOM element that lets the user pick which and so every time the table gets rendered (which happens basically after any change, or manually triggered need be), the cells in the columns specified will be hidden, keeping the data array intact like you described. And when not in colsToHide they are re-rendered so make sure you get that working as well.
Here I implemented it with very basic functionality. Just enter the index of a column into the input fields and watch the magic happen.
http://jsfiddle.net/zekedroid/LkLkd405/2/
Better Solution: handsontable: hide some columns without changing data array/object
I have a slickgrid that, in the 'onMouseEnter' event, I do the following:
change the underlying css for the row in question
call grid.invalidateRow()
call grid.render()
These latter two calls are necessary for the new css classes to be reflected. However, I then need to capture the onMouseLeave event, and it is not fired when I move my mouse away from the cell (or row), presumably because the call to invalidate/render has placed a new DOM element under my mouse, and it's no longer the one I initially "entered."
So I have two questions:
Is there another way to have the new css classes for a given cell be rendered without calling invalidateRow/render?
If not, is there another way to do this and still have the onMouseLeave event fired?
One option is to use the setCellCssStyles function.
grid.onMouseEnter.subscribe(function(e, args){
var cell = grid.getCellFromEvent(e),
param = {},
columnCss = {};
for(index in columns){
var id = columns[index].id;
columnCss[id] = 'my_highlighter_style'
}
param[cell.row] = columnCss
args.grid.setCellCssStyles("row_highlighter", param);
})
So the above changes the background-color of every cell of the row that has been moused into. In my fiddle, the mouseLeave subscription performs a simple console.log to ensure it is still firing.
Edit: fixed the external resource usages in the fiddle for cross-browser support