I have a listbox in which multiple list items are there. I want to implement something like if we click on the list item, it will collapse and show the summary of the clicked item:
I have been searching this on the web for quite sometime but haven't got any good solution. I am very new to Win32. Any suggestions on how to approach this like which control should I use. Any help will be appreciated.
Standard ListBox and ListView controls do not natively support expanding/collapsing items, however it is possible to implement it in a ListBox with some extra work.
Give the ListBox the LBS_OWNERDRAWVARIABLE list box style to allow the list to contain items of different heights. When a new item is added to the list, the ListBox will send a WM_MEASUREITEM message to its parent window asking for the item's initial height. Return an appropriate height based on whether the item should be displayed as collapsed or expanded.
Once an item has been added to the list, you can send the ListBox a LB_SETITEMHEIGHT message to assign a new height for that item based on whether it should now be displayed collapsed or expanded. Then invalidate the ListBox to trigger a repaint of the items.
The LBS_OWNERDRAW... styles require you to manually draw each list item whenever the ListBox sends a WM_DRAWITEM message to its parent window. You can draw the requested item on the provided HDC however you want, such as with the DrawText() function, configuring its parameters based on whether the item's text is currently being displayed as collapsed or expanded. Also use the state information provided by the message itself to configure the HDC's font and background/foreground colors as desired (particularly important when rendering items in the selected and focused states).
With that in place, all you have left to do is make your click handler determine the index of the item being clicked on (via GetMessagePos(), ScreenToClient(), and LB_ITEMFROMPOINT), and then assign it a new height based on its new expanded/collapsed state, and let the resulting repaint draw the new text accordingly.
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My app needs to be small in nature so I make it 500 x 100 px in size.
The problem is the ComboBox selection items are also squeezed into that small window size. Of course, I can scroll it, but it doesn't feel right this way.
Here is the picture:
Is it possible to expand the ComboBox selection list so that it exceeds the parent window? Preferably in XAML if possible
Is it possible to expand the ComboBox selection list so that it exceeds the parent window?
No, this is impossible in UWP apps. While using ComboBox class, it displays the drop-down list in PopupRoot, which is a layer has the same view port as its parent window. Anything outside this view port will be clipped, users can't see them. For example, following is a normal ComboBox:
After I give a Margin="-20,-30,0,0" to the drop-down list, it looks like
The part outside the window is clipped.
Besides, The implementation of ComboBox will also make sure the ComboBox's selection list won't exceeds the parent window. The selection list's max height is calculated at runtime, it will be always less than the parent window's height and we can't change its value manually, so it is not possible to expand the ComboBox's selection list.
It's not possible, but you can extend your page to the title bar to have at least some additional space using CoreApplicationViewTitleBar.ExtendViewIntoTitleBar property.
Take a look here and here. (I know the examples are written in C# but it should be similar in C++)
Is there any way to add QActions as a list item on QListWidget?
I want to make a customization window which will show list of actions on a widget for move up, move down, Rename and other options. I'd like to display it on the widget same as it appears as a context menu.
I tried adding it as a list item with icon and text, but the look it not very good:
i) list items with blank icon are not aligning properly, even after adding a blank icon of size 16*16 is not taking up any space and text with icons & w/o icon are not aligning.
ii) I'm unable to add right-pointing black triangle at the right most, in-case of sub-menus cause somehow unicode character for this is not getting displayed on my Linux machine.
That's why I want to add QActions as it are getting popped at original place.
Any suggestions?
Yes I have a suggestion : do not try to make fancy widgets like this, users will not find it intuitive
You should find another way to implement this.
Imo, something like a QToolButton with a QToolButton::MenuButtonPopup popup mode will do the trick. This way, you can embed menu and sub-menus in a widget, using QToolButton::setMenu().
I am maintaining a ATL/WTL project in which it contains a tree view. The class used for the tree view is CTreeViewCtrl. Now the client has asked to wrap the tree item text when it goes out of view though we can re-size the pane or scroll left of right anytime to see the content. It also shows the full string, when hidden, as a tool tip when mouse pointer is hovered on a tree item.
Is there any way I can set in the tree item or the tree view to wrap the text content.
Thanks
There's a way: do custom drawing of treeview's items while processing NM_CUSTOMDRAW message from treeview control, specifically the CDDS_ITEMPOSTPAINT drawing stage.
On custom drawing you draw multi-line text using ::DrawText() with DT_WORDBREAK flag.
In order to have enough space available for text to fit in use TVITEMEX structure's iIntegral field. You'll have to specify number of lines for each node by sending TVM_SETITEM message to treeview window with pointer to TVITEMEX as LPARAM. You'll have to recalculate number of lines for each of tree's nodes every time treeview's width changes (WM_SIZE).
I have a CTreeListCtrl in my MFC application.What I need to do is add a button in a particular column of a node when a particular condition is satisfied(type is changed to reference).
In the image I have edited and added a blue rounded oval to mark the place of desired button.What I want to do is to invoke a dialog on clicking it.But I don't have any clue whether it is possible or not.If yes then pls give me some suggesions.
This is no normal tree control. It is already customized to use multiple columns and I am sure it uses some kid of owner draw. For me it seams more like a list control with tree Features... I know some similar code from Codepproject..
Creating a "real" button (window) isn't wise/good. because it is another window inside the list control...
Change your code to "Draw a button. You can use DrawFrameControl.
Just intercept the left mouse click. Check the range if this area is cliecked. Fire a user defined message to the parent window.
I have created a List view control with View = Icon / List, with LVS_EX_CHECKBOXES enabled.
And the checkboxes overlap with the items text, so I am wondering how could I create a owner drawn list view with checkboxes ?
I have seen that one has to process LVN_ITEMCHANGED notitication to test if an item has been checked.
How does this apply when the checkbox itself gets owner drawn, how do I approach this problem.
How Do I manage the events, the checkbox checking and unchecking while drawing my own, do I have to implement the checking routines myself or do I get something from the window? A message or something? While drawing my own checkbox how do I differentiate between a click on the item and a click on the checkbox, do I have to check the coordinates of the cursor when the click occured? how do I do this.
THis is with view= icon, it shows ok with view=list