I'm just starting to use SlickGrid but I've had a lot of success creating a remote model that can interact with the paging plugin. The only problem I have seems to be a browser issue, but I'm curious if anyone knows a trick that may resolve the issue.
I'm retrieving the data page by page in my model via AJAX and updating the grid with the grid.setData() and grid.render() methods.
The problem I would like to solve is that when the length of data changes the vertical scroll bar gets really confused, unless I change the current visibility of the filter panel (grid.hideTopPanel() or grid.showTopPanel()). By confused I mean that the scroll handle in the scroll bar doesn't change size to indicate the different number of rows that are now current, and if the list grows, the scroll handle size jumps all over the place as I scroll up and down.
I'm assuming the "fix" works because it forces the browser to recalculate the view port height, but is there any way to force that to happen? Or is there a better way to do what I'm trying to do?
Ok mleibman straightened me out, what I actually was looking for was grid.updateRowCount(). I believe he will be adding a call to this in grid.setData(), but for now just make sure the 2 method calls are used together.
Have you tried grid.invalidate() ? Im my experience that forces the grid to recalculate pretty much everything. It may be more heavy-handed than you need but at least you can see if a complete invalidate solves the problem.
I figured it out. You need to call grid.resizeCanvas() after calling grid.setData(). It seems like this should be part of the grid.setData() method because a call to it will change the number of rows. But anyway, that's what you need to do.
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I have a grid in ExtJS 6.0.2 that can be set to auto-refresh (it reloads once every ~10 seconds), but when it does, I want it to stay where it is instead of scrolling to the top each time. We have successfully used preserveScrollOnRefresh to do this with other grids, but for one particular grid, it's not working. In order to try to get it working, I decided to try calling getScrollY() before reloading the store and setScrollY() after, but that didn't work either. When I stepped through with the debugger, for some reason, getScrollY() returned 0 even when I had the grid scrolled all the way to the bottom.
Is there anything else that I can try?
it sounds like this is working for other grids in your app, so without seeing any code I'd suggest that something with that store/grid ecosystem is not configured the same as other grids in your app.
perhaps post a fiddle (fiddle.sencha.com) with an example, that may also help you find your answer if the fiddle works.
Just using 'mix-blend-mode:overlay' on a text element and it causes my browser to scroll really slow while the text is in the screen view. As soon as you scroll past the text item, the scroll goes back to butter smooth.
The lag effect, which affects both chrome and firefox is solved if I remove the mix-blend-mode.
Has anyone else had a similar problem with mix-blend-mode?
Not sure if this will help you in your case, but I had a 'transform: scale(-1);' set on element that had 'mix-blend-mode' enabled. When I removed the transform the performance was silky smooth! So, if you're using any sort of 'transform' I'd remove it and look for an alternative solution if possible.
It may also help if you set 'isolation' property to the layer beneath, as per example here: https://developer.mozilla.org/en-US/docs/Web/CSS/mix-blend-mode#HTML_example
what does Recalculate Layout Paint mean in chrome developer tool TimeLine records? and how to improve the page performance by reduce the page Recalculate,Layout and Paint's count? can give some suggestion?thanks
Basically, they're your browser figuring out how to draw the changes that you made to the page.
Don't worry about getting rid of them -- if you did that, your site would be static.
However... ...if you want to do something that IS useful for performance, which does have to do with reflows and repaints, then batch your changes together.
Lets say that you got a job at Twitter.
And your job is to write the next version of the window that adds each twitter post to the screen.
If a user gets 250 new tweets in their timeline, and you add each one in a loop, one after the other, the browser is going to slow way down, because every time you add one, it will have to reflow (move things around to make space for the thing you added) and repaint (style everything that was affected by the addition).
A better way of doing it would be to build the list of new tweets together off-DOM (ie: with elements that aren't actually on the page right now), and then add them all at once.
This cuts down on the number of times that a browser has to figure out where everything needs to go.
#Fabricio -- Micro-optimizing might not be great, but appending hundreds of browser elements in a loop, versus putting all of them in at the same time can make a big difference.
Just ask the Twitter guys, who weren't bothering to cache their jQuery objects.
Here's a very handy list of properties and methods that trigger the layout (reflow) of a page:
http://gent.ilcore.com/2011/03/how-not-to-trigger-layout-in-webkit.html
You want to minimize these calls as much as possible -- especially in situations where performance is critical, such as during the scroll event, or when animating large blocks of content.
You can use the "Profiles" tab and "Audits" tab to detect the performance of your code. The will give you a report about your codes.
You can reduce the page Recalculate,Layout and Paint's count by many ways.
Append many child at one time.
Hide elements before change them.
Give images and other elements height and width.
when i use pivot with in the panorama .pivot are used as a gallery view. i want to move pivot when i swipe it .but the problem is this because of both panorama and pivot are the same gesture event so both are they move .
i want swipe only my pivot view .
I would like some sample code or any other suggestion to do this.
so please give me a solution for doing this and
also give me a link where i easily understand this. Thanx in advance
You shouldn't have a Pivot in a Panorama control. End of discussion.
I believe it is achievable, because I've already solved similar issues with having WebBrowser control inside a custom horizontal-scrollable overview container like Pivot/Panorama, but believe me, it is NOT worth it. I've had to dig very deep into the visualstructure of the controls and attach my own manipulation-handlers to their viscera, manually choose which horiz/verti events to pass and which to cancel, and so on. This is not so easy, takes a lot of time, and doesn't guarantee that on the end you will have something behaving in a way you wanted to achieve in the first place. If you are not bound by some contract to preserve the shape of the UI, please, drop the idea and redesign your UI, just to save on your sanity and nerves.
But, if you are already insane or really want to dig where noone should, start on analysing your UI as a two rectangles: large pano and small pivo, and think which part should behave how on different possible touches/h-v swipes/h-v pans/pinches/so on. Write it down just to for reference, or soon you will probably start making small mistakes that will interfere with your understaning of the flow of the events.
I've checked the version I have, and "my" Panorama uses internally the UIElement.ManipulationXXXX events. In that case:
Display visualtrees of your UI and try attaching manipulation-events to every control. In those events, write/log which control's which handler was invoked. Then make some swipe/scroll on your APP and observe events. Analyze how they were bubbling and try cancelling (e.Handled=true) the manipulation-completed and/or manipulation-delta events somewhere between pivot and panorama. Your goal is to have the panorama see that e.Handled=true, while your pivot must see e.Handled=false. Your Pivot will probably see the event sooner than the Pano, so that point should be relatively easy.
If it fails to work, then you should check your version of the Pano, and check how it detects movements. If, for example, it uses the GestureListener - try the same trick with it. Etc.
And remember, you can always make your own horizontal-overwiew-container that will look like Pano, behave like Pano, and that will work with Pivo better - because it will be your code and you will tell it what and when to move. if you want to go this way, start on google and check all the preliminary Panorama previews that random people have published before that control was published by MS.
It's a longshot that anyone can help with this, but here goes. I inherited a VB6 app with a Janus GridEX control. It iterates through records, and is editable. Problem is, if I edit a cell and hit the button to go to the next record, the change is applied to the next record, not the one I was editing. It's like, I need it to finish up the edit before going to the next record. I've had this sort of problem before in VC++, and sometimes you have to "KillFocus" on the control you're on or something. I just don't know what to do here. I tried sending a carriage return, since if you return out of the edit cell, it works, but sending a carriage return manually doesn't work. What's the secret?
Is your grid bound or unbound?
It's hard to tell from your description, but I imagine that if your are having this problem then it's probably bound.
As the other answer asked, is the button the RecordNavigator that is built into the control or is it a separate button? The reason I bring this up again, is that I have seen issues in the VB6 applications I support where a toolbar will often intercept and interfere with how the JanusGrid should work.
To get around this limitation, I have added the following code in the click handler of any toolbars where there is also a JanusGrid control on the form.
If jsgxYourGridName.EditMode = jgexEditModeOn Then jsgxYourGridName.Update
This way any changes are immediately applied to the current row.
If this does not help, then I have also seen problems where the recordset that is bound to the grid gets out of sync with the internal recordset in the grid. You can check this by comparing the bookmark of the grid to the bookmark of the recordset.
Ie. mrsYourRecordset.Bookmark = jsgxYourGrid.ADORecordset.Bookmark
At one point I may have also used something like this.
jsgxYourGrid.ADORecordset.Bookmark = jsgxYourGrid.RowBookmark(jsgxYourGrid.RowIndex(jsgxYourGrid.Row))
Finally you can try setting a breakpoint in the BeforeUpdate, RowColChange and/or AfterColUpdate events of the grid, to see what record the grid is really on when clicking on the button.
It depends whether the button is internal to Janus GridEX or not. If it internal then just about the only thing you can do is look at the events the control exposes to see if there a sequence that can let you know that this problem occurs. Then you can try to take corrective action by restoring the row you moved to and put the edit in the row you left.
If the button is external to Janus then you can use the debug mode to trace sequence of statement that control the transfer of focus to the next row. It could be something out of order or a side effect of the particular sequence of commands. I have run into both with different controls.
Remember that you can edit while in debug mode so you can try different approaches and test until you find one that works.