Not sure I'm asking the right question, but it's a start. I have a user control with a ListView and, ideally, I would like to nest this same control inside of the ListView to provide recursion. This would behave somewhat like a TreeView with child nodes.
This might be a monumentally bad idea. :) In fact, I feed like MSFT is pointing me in that direction, because when I try this I am told that I can't do it.
So, how would you do this? What's the right way?
Sounds like You do need a TreeView after all, but need more functionality than it provides by default... How about extending the TreeNode/TreeView?
Here is an example for that:
http://www.codeproject.com/KB/tree/DropDownTreeView.aspx
Or you can extend the ListView, in fact, this article shows how to create a TreeListView which sounds very similar to what you're trying to do:
http://www.codeproject.com/KB/list/extendedlistviews.aspx
Either way, it sounds like you need a custom control, based on the TreeView and ListView.
Good Luck!
Related
I’ve been using Xamarin.Forms for a bit lately and can generally get enough information following the Microsoft docs. But I seem to be stuck now that I need to create a custom renderer, so if someone could help, I’d really appreciate.
I read through the docs on creating a custom render and maybe I missed the part I’m looking for, but I’m not able to tell if as part of OnElementChanged, I also need to render all the children of the Element?
The ContentPage could have a StackLayout for example with several child elements. If I dont have to render these, how do they get rendered/laid-out?
No, you don't need to render ContentPage's children.
When you create a Custom Renderer you are only extending Xamarin's renderer, meaning you only add functionality (unless you explicitly change something, like redefining a property).
So, basically, the ContentPage render/lay-out the children the same way it renders/lays-out without the Custom Renderer.
Answering your second question, actually the layout and positioning is done without renderers, as said here Xamarin.Forms Layouts.
If you want to dig deeper, you can try to understand how the ContentView (it's the easier one) is positioned by reading the source code. Here the TemplatedView (ContentView's base class) is calling LayoutChildIntoBoundingRegion for each of its children: TemplatedView.
Then this line on the LayoutChildIntoBoundingRegion calls the Layout method of the view: Layout.
The VisualElement.Layout method only gets the rectangle and sets the Bounds of the view (Layout Method). The Bounds setter is called: Setter.
Well, now you can go on and explore more of the source code if you want, but I think you got the idea ;)
Hope it helps!
I understand that treeview in asp.net comes with checkboxes option for usage. However, in my application, I will require 2 additional checkboxes or radiobutton on the righthand side of each leaf node of my treeview.
However, I seem to be unable to find a solution to this requirement, and i think treeview structure does not support this feature.
I'm new to asp and I'm not sure if there is any other class which i can use upon to implement this feature.
Hope I can have some ideas from you guys to implement this
All help is appreciated
Thanks!
Regards
bernerd
The tree view control is quite limited however I've found this project http://www.codeproject.com/Articles/43057/ASTreeView-Free-ASP-NET-TreeView-Control which has extended its functionality - check out the reference and see if it provides what you need OR use it as a base to extend it as your scope requires!
i am wondering if there is a way to skin the whole drop down box, after searching Google i could only find thing like adding icons resizing and alike, but no full skinning of the box.
Is this at all possible and if so how? i would very much like my whole program to be skinned rather than everything but the drop down boxes.
I am more of a designer than a coder so as far as code goes I'm quite a novice with the code side, would be a great help if you could give me a point in the right direction and/or a quick insight how to do it.
in flex... sorry
Thanks.
i am wondering if there is a way to skin the whole drop down box,
Yes, create a custom skin class for the DropDownList, just like you would any other Spark class. You can use code for the DropDownListSkin as a reference point for creating your own. In Flash Builder, if you create a new MXML Skin; and specify the hostComponent as a DropDownList then you'll get the DropDownListSkin code as a starter point for your customization.
For more info, read these docs on skinning Spark Components.
We did, in essence, exactly this to create our Mobile DropDownList.
I am trying to make a side panel in a Flex application that would hold a bunch of properties of a selected object. The number of properties may become huge, but they all fall into some certain categories.
For that, I am looking for a flex control that would be like a collapsible field group. Or like an accordion that can have multiple open panels at a time. Do you know, where can I get one?
UPDATE: I want something like the second example on the following page: http://extjs.com/deploy/dev/examples/form/dynamic.html
Thanks,
Artem.
http://www.flexdownloads.com/#view=detail;vstr1=19
is what you are looking for.
It sounds to me like you are looking for some sort of tree component. Flex actually has one of those and you should probably take a look at it.
This is a good link to see what controls are included in flex http://examples.adobe.com/flex3/componentexplorer/explorer.html
I've got a QTableView for which I want to display the last column always in edit mode. (It's a QComboBox where the user should be able to always change the value.)
I think I've seen the solution in the Qt documentation, but I can't find it anymore. Is there a simple way of doing it?
I think I could archive this effect by using openPersistentEditor() for every cell, but I'm looking for a better way. (Like specifying it only one time for the whole column.)
One way to get the automatic editing behaviour is to call the view's setEditTriggers() function with the QAbstractItemView::AllEditTriggers value.
To display the contents of a given column in a certain way, take a look at QAbstractItemView::setItemDelegateForColumn(). This will let you specify a custom delegate just for those items that need it. However, it won't automatically create an editor widget for each of them (there could in principle be thousands of them), but you could use the delegate to render each item in a way that makes it look like an editor widget.
There are two possibilities:
Using setIndexWidget, but Trolltech writes:
This function should only be used to
display static content within the
visible area corresponding to an item
of data. If you want to display custom
dynamic content or implement a custom
editor widget, subclass QItemDelegate
instead.
(And it breaks the Model/View pattern…)
Or using a delegate's paint method. But here you have to implement everything like enabled/disabled elements yourself.
The QAbstractItemModel::flags virtual function is called to test if an item is editable (see Qt::ItemIsEditable). Take a look at Making the Model Editable in the Model/View Programming documentation.
I can't see an easy way to do this, but you might be able to manage by using a delegate. I honestly don't know exactly how it would work, but you should be able to get something working if you try hard enough. If you get a proper delegate, you should be able to set it on a whole view, one cell of a view, or just a column or row.