When using virtual scrolling and number of rows changes then the scrollbar's thumb may remain below available data.
Scenario:
Use virtual scrolling and async data binding
Load e. g. 1000 rows
Scroll to the end
Change the data to e. g. 100
Problem:
The thumb remains at the bottom and no data is actually visible. You can scroll up again, but it is confusing for the user and it would be better to scroll to the top programmatically.
Question:
Is there a way to scroll to the top programmatically?
Try Element.scrollTop
If it is angular app, you can use the following code:
let gridContent = this.elRef.nativeElement.getElementsByClassName('k-grid-content')[0];
if (gridContent) {
gridContent.scrollTop = 0;
}
where elRef is passed using consturctor:
constructor(private elRef: ElementRef) { }
Related
I've 3 (loader, locker and debug view) hidden views (touchEnabled and visible set to false, and zIndex to 1) above the main view (zIndex = 2).
Each 'over' view has this method:
$.debugView.show = function() {
$.debugView.touchEnabled = $.debugView.visible = true;
$.debugView.zIndex = 3;
};
$.debugView.hide = function() {
$.debugView.touchEnabled = $.debugView.visible = false;
$.debugView.zIndex = 1;
};
This screen has the 3 'over' views hidden:
Now, I'm opening the 'debug view', but, SOMETIMES it seems like it changes the positions (as if the center it's on the top left corner instead of the center of the device).
Instead of the required result:
If I use the opacity instead of the visible property, it works properly.
This might be an SDK bug right?
<Alloy>
<Window>
<View id="content"/>
<View id="locker"/>
<View id="loader"/>
<View id="debugView"/>
</Window>
</Alloy>
All of these 4 views don't have width or height (so it uses the Ti.UI.FILL as default)
I have noticed this too with a completely different implementation. I had just one view that I included in a window.
Apparently the left and top calculations were not done properly if the elements is hidden.
What I did to solve the issue is to hardcode the left/top position by calculating the left position using this:
$.content.left = (Ti.Platform.displayCaps.platformWidth - 75) / 2;
Where in my case 75 is the width the element has, so that'll be bigger in your case. You can do the same for height.
Now, this is an iOS only solution. On Android you will need to take DPI into consideration calculating it.
I do think it is a bug, though this solution works perfectly for me. I recommend looking at JIRA and see if it is a known issue, and if not, raise it with a very specific explanation of the problem, preferably with a reproducible case delivered as an app. Classic would help most. And if it is not reproducible in classic it might be an alloy issue.
I am using c1truedbgrid. I have columns added in the grid with one column having button which is displayed is every row. I need to disable the button in a particular row depending on some business logic. How this can be done?
I am not sure why there aren't any answer.
Its fairly simple. Lets say I want to disable the buttons from those rows where ID is even.
for(int i = 0; i< c1truedbgridobject.Splits[0].Rows.Count; i++)
{
if(Convert.ToInt32(c1truedbgridobject[i,1].ToString())%2 == 0)
{
//Disable here
}
}
However the disable part is dependent on how you are adding button to a cell. Since add button is referenced to whole column and not to a particular cell.
Anyhow using a OwnerDrawCell is also an option.
EDIT:
This seems as a limitation of C1TrueDBGrid. You may use C1FlexGrid as an alternative.
You need to make property of that column as "locked=True" as Below example when you initializing grid.
C1TrueDbGridName.Splits(0).DisplayColumns("YourColumnNameHavingButton").Locked = True
it will make your row not to be editable
MFC doc/view architecture, sdi (more precisely multiple top-level windows).
In my view class, I set my "playground" (i.e. logical space) with SetScrollSizes(); Then I want to limit maximum frame window size to that of view's maximum size.
Here is what I'm doing but I think there might be better solution, please advice:
I'm implementing OnGetMinMaxInfo() in my CMainFrame. There I try to get active view's scroll sizes, and set lpMMI->ptMaxTrackSize appropriately. Below is the code:
void CMainFrame::OnGetMinMaxInfo(MINMAXINFO* lpMMI)
{
// Call base version:
CFrameWndEx::OnGetMinMaxInfo(lpMMI);
// Get active view:
CScrollView *pScrollView = (CScrollView *)GetActiveView();
if (pScrollView && pScrollView->IsKindOf(RUNTIME_CLASS(CMyFckinView)))
{
// Get total size of playground:
CSize sizePlayground = pScrollView->GetTotalSize();
// Test if the size is non-zero, i.e. there is at least one node displayed:
if (sizePlayground.cx && sizePlayground.cy/* && !IsPrintPreview()*/)
{
// Set maximum window size to match our playground size:
CRect rectClient, rectWindow;
pScrollView->GetClientRect(&rectClient);
this->GetWindowRect(&rectWindow);
if (rectWindow.top > -5000 && rectWindow.left > -5000) // Avoid when minimized...
{
lpMMI->ptMaxTrackSize.x = sizePlayground.cx + (rectWindow.Width() - rectClient.Width());
lpMMI->ptMaxTrackSize.y = sizePlayground.cy + (rectWindow.Height() - rectClient.Height());
return;
}
}
}
}
This works but has one problem: When print preview is displayed (standard MFC print preview), I obviously want to allow free window resizing, so I use runtime info GetActiveView()->IsKindOf(...) to determine that active view is really my view, and not print-preview's view (which is CPreviewViewEx). But when I close the print preview, OnGetMinMaxInfo is not called, so I'm unable to adjust frame size according to my view again. As soon as I move the window OnGetMinMaxInfo gets called again and correctly adjusts frame size, but without manually moving the window old size (to which the print preview was sized to) is retained and has ugly artifact.
What can I do? Basically if I could trap the moment when print preview is closed, I could use following trick:
// Trigger the WM_MINMAXINFO message:
CFrameWnd *pFrame = GetParentFrame();
RECT rectWindow;
pFrame->GetWindowRect(&rectWindow);
pFrame->MoveWindow(&rectWindow);
But I don't know how to trap print-preview closure.
What I'm trying to accomplish seems quite standard: who would want to have frame window resized bigger than view's logical size (set by SetScrollSizes())? So there should be some more natural solution maybe?
In your CMyFckinView, handle a message that is reliably sent when the print preview is closed and then post a user message to the mainframe which will trigger your "force minmax" code. Perhaps WM_FOCUS or WM_ACTIVATE?
I have a FlowLayoutPanel and a UserControl.
I've added multiple usercontrols into the FlowLayoutPanel, and I'm trying to dock them to the top, so when I change the size of the FlowLayoutPanel the size (width) of the usercontrols changes accordingly.
You cannot dock anything inside a FlowLayoutPanel, it's simply ignored.
Check out the answer here apparently posted by the Microsoft team.
They say:
The FlowLayoutPanel relies on a largest control to effectively define the column/row within it. The code below set's the size of the first control to the width of the FLP to achieve a layout similar to what you want.
private void flowLayoutPanel1_Layout(object sender, LayoutEventArgs e)
{
flowLayoutPanel1.Controls[0].Dock = DockStyle.None;
for (int i = 1; i < flowLayoutPanel1.Controls.Count; i++)
{
flowLayoutPanel1.Controls[i].Dock = DockStyle.Top;
}
flowLayoutPanel1.Controls[0].Width = flowLayoutPanel1.DisplayRectangle.Width - flowLayoutPanel1.Controls[0].Margin.Horizontal;
}
Key thing is to use the Layout event.
This solution worked for me up to a point. Your UserControls have to have AutoSize turned off / stay a uniform size.
In my case I wanted AutoSize turned on so as to allow the UserControl to expand/contract vertically while filling the width of the FlowLayoutPanel.
I had to find a different solution. But the above might help you in your case.
I have a resizeable CListCtrl and I want to avoid any item being displayed partially, ever.
For example:
I want Item 9 to not be displayed in this case. Is there a flag or method for this? How would you go about solving this issue?
I tried the following and it was no good:
void CMyCListCtrl::OnEndScrolling()
{
int iCount = this->GetCountPerPage();
EnsureVisible(iCount - 1, FALSE);
}
after catching
...
ON_NOTIFY( LVN_ENDSCROLL, IDC_LIST1, OnEndScroll )
...
void CWheelTestDlg::OnEndScroll(NMHDR* pNMHDR, LRESULT* pResult)
{
LPNMLVSCROLL pnmLVScroll = (LPNMLVSCROLL) pNMHDR;
m_MyListCtrl.OnEndScrolling();
*pResult = 0;
}
In the CListCtrl parent dialog. (which I don't want to do, I want to do everything in my CListCtrl derived class only, if possible).
All I accomplish is showing item 9 completely, but item 10 is partially visible below it. If I have 30 items I don't want to scroll the list to show item 30, I want to show up to item 8 with no partially visible item below it.
CListCtrl doesn't appear to support Integral Height.
Here's a solution that accomplishes what you desire by forcefully changing the control height [with commented conditions] (http://www.codeproject.com/Messages/418084/Socket-accept-call.aspx):
/////////////////////////////////////////////////////////////////////////////////
// This assumes a REPORT-style CListCtrl.
//
// Resize the control. This works correctly only if scrolling is disabled. If
// there is scrolling, then setting to the size from ApproximateViewRect() will
// always give scroll bars showing. Which is irritating.
//
// We need to adjust the vertical size from what ApproximateViewRect() returns
// by one row minus border width
//////////////////////////////////////////////////////////////////////////////////
CSize sz = m_list.ApproximateViewRect(); // always adds room for a new row
CRect itRect; // Get the height of a single row (there had better *be* a row!)
m_list.GetItemRect(0, &itRect, LVIR_BOUNDS);
int vOffset = itRect.Height() - 3; // leave a little 'cuz it looks better
m_list.SetWindowPos(NULL, 0, 0, sz.cx, sz.cy - vOffset,
SWP_NOZORDER|SWP_NOACTIVATE|SWP_NOMOVE);
I have the similar problem in wince, and find a solution accidentally. No direct solution in internet, so i decide to re-position scroll bar after receive some message, and the only message i can used in wince is WM_LBUTTONDOWN, other messages such as OnEndScroll are not called, maybe something wrong in my code.
Whatever, i use Timer（ON_WM_TIMER） to re-position scroll bar when receive WM_LBUTTONDOWN message, then find that list control doesn't scroll automatically! then i remain a empty OnTimer function and remove everything else. It works, and i guess list control use Timer to scroll partial row.
Hope useful to you.