I have a listView that has a textField in the item template. To make sure that the listView saves the data I have used the code from this link it works in that it saves the data to the listView item but it looses focus every time the onChange event fires the updateItemAt method so the keyboard disappears after every key press.
I have tried onBlur but I then get the original text flashing up before it is replaced with the new text from the blur event.
Is there a way to stop loosing focus when the updateItemAt listView method is fired?
No, there is not, because by updateItemAt you are re-rendering that row.
Also, its not a best practice to store data in proxy objects. Better store the data in the data collection that drives your listview or a separate object/array.
Related
I have a scrollviewer in page which shows data vertically, and it contains controls like grid, stackpanel and listbox.
Listbox contains items with expanderview. On click of expander view header it expands, I just want that whenever it expands its content get visible in page. Means i have to automatically change scroll position and make visible a Listbox selected control.
Is there any way?
There is a way to manage it Programatically with use of Timer. When the timer is triggerd, we call the timer_Tick event handler, which scrolls to the current index and marks it as selected, and then updates the index. After the last item is highlighted the index is reset to the first item. You can find useful sample here Auto-scrolling ListBox for Windows Phone
You need to calculate the offset where you want to scroll to, and then use ScrollToVerticalOffset(your_offset_value) method.
Have a look over here : How to use ScrollViewer.ScrollToVerticalOffset?
i have developed custom control which inherits Button control, actually i`m creating button with one picturebox and label on Button(picturebox and label are child controls). I created same method and wired child controls to behave as clicking on parent(Button), it works but its slow no mather what i do(tried with InvokeOnClick, me.performclick, Me.OnClick(New EventArgs()), tried with same method for all events), but clicking on label or picture box is slow, i need it to be fast as clicking directly on button cause in my application is very important to be able to click on button twice in second for example, if you click on label or picturebox twice at second it will fire just one time not 2.
What i have been thinking of is to make label and picturebox invisible for event is it possible or anyother idea ?
Thanks in forward
You are doing battle with ControlStyles.StandardDoubleClick. Which is turned on for the PictureBox and Label controls but turned off for Button.
So when you are clicking rapidly on either the picturebox or the label then they'll generate the DoubleClick event instead of the Click event. You'll interpret that as "slow" since you probably didn't write a handler for that event. Subscribing the event and calling Me.OnClick is a workaround.
Just don't do this. PictureBox and Label are point-and-click convenience controls but they are extraordinarily wasteful. It takes just two lines of code in the button's OnPaint() method override to get the exact same outcome, minus the overhead and the event problems. Use e.Graphics.DrawImage() to draw the pb's image and TextRenderer.DrawText() to draw the label's text.
Using MouseDown event ensures the event is triggered once per click, regardless of click/doubleclick.
I am using Visual Basic.net and have a question: If I have a piece of code, such as refreshing a ListView, and the form that the ListView is on is not currently visible, does this code execute? I am just wondering if it is a waste of memory to execute this code, or if it is not executed at all.
If you're firing a timer, and that timer is executing code that refreshes the display of the list view, it will execute, but the display will not refresh until you ... actually display it to the user.
In other words, the ListView's state gets updated with the changes, but the changes aren't displayed until the form is visible. No video card pixels are harmed in the updating of the hidden ListView, in other words.
Refreshing listview doesn't harm/waste memory unless the data(Listview items) are too many. If your code contains retrival of listview items for some other controls or dynamic manipulations based on data/items from the listview then refreshing listview is needed.
How do we detect a scrolling event in GridView (like ViewChanged on ScrollViewer) on somethig like the default GridView template sample app? I'd like to replicate the effect that the netflix App does on the left red strip.
I tried putting the GridView inside a scrollviewer, but I've been unsuccessful at stretching it to fill the screen for different resolutions.
Update: I intend to use this with VariableGrid control that's on NuGet - though it's not an official control, it inherits GridView
The best way to do this seems that you can read through the components of the control, and assign events to it. based on what's happening in this example
http://mikaelkoskinen.net/post/WinRT-XAML-Automatically-Scrolling-ListView-to-Bottom-and-Detecting-When-ListView-is-Scrolled.aspx
I grabbed access to the scrollbar, suing the VisualTreeExtensions and I could capture the event Scroll, just like in the example. I had to read the children when the Loaded event of the grid was fired.
There is a simpler way.
Edit a template of the GridView, and look inside the XAML to find a ScrollViewer which is a component of the GridView.
The ScrollViewer has a ViewChanged event that you can subscribe to. Now whenever the GridView is scrolled, this event will be fired.
Try ManipulationCompleted and PointerReleased events on GridView. This is just using keyboard mouse..
I’m trying to make a button that displays an image, that’s easy, but the image is an editable icon so I want the image on the button to be updated every time the form is started how can this be done?
I am making the assumption that you are using WinForms and saving your editied icon to a file.
Take a look at this MSDN page on ButtonBase.Image Property.
From above link:
button1.Image = Image.FromFile("C:\Graphics\MyBitmap.bmp")
You can put this in the New Subroutine after the InitializeComponent Statement. or in your Form Load event.
Use Graphics method and also handle the Paint event of Button. You can add text and primitive drawing on Image or Button region.