My program's GUI has a table with a textbox in each cell. When the user types something on a cell I want my program to get that something, plus the row and column the cell occupies on the table.
Creating an event for each cell manually is a lot of work, and each event would do the same thing, so I was wondering if there's an easier way to do this?
You can use one event handler function for several events, in your case the problem is to determine who has raised the event.
It is important to mention that tablelayout panels don't actually have cells, where you could think of container of objects. Some tricks have mentioned here for how to detect clicked row and column of changed textboxes(this link provided example of buttons but it is the same for texboxes too) but I highly recommend to use GridViews instead.
Related
I have an app which allows users to send messages to each. The process is accomplished by saving the sent messages in a local SQLite database, while actually sending the messages to a database and using push notifications to send the message to the recipient's SQLite database. The set up I have works fine. However, what I am confused about is how to set up the actual interactive UI for the user (I am using XCode). I figured it should be a UITableView with each table cell representing a message. However, with this approach I run into a few requirements:
Variable TextView Sizes
Just as with regular iOS messaging, the TextView's size needs to be variable, adjusting its dimensions to fit all of the text in each message. I do not know how to accomplish this. I have a general understanding of how to generally vary sizes, but no clue how to dynamically have it based on the text within that view.
Variable TextView Positions
Again, just as with regular iOS messaging, the textview needs to be offset to either the right or left side depending on whether the sender was the user or who the are conversing with, respectively. I also do not know how to do this, because it changes the center of the textview.
Non-selectability
Xcode allows cells to be pressed. Handling what happens after this selection can be achieved by the didSelectRowatIndexPath tableView function. I can simply not implement this, but clicking on the cell causes it to turn darker to indicate it has been pressed. I would like to eliminate this while retaining the ability to, say, select some of the text and copy and paste it or whatever (just like messaging works normally on your phone).
Other Approaches?
This is the real meat of the question. I have considered the above approach because that is all that I have been able to come up with based on my limited experience with XCode UI elements. If there is a better approach (perhaps even a pod or framework) for this purpose I would love to hear it. I do not need the messaging UI to look amazing, just clean and crisp.
I suggest the following:
Variable TextView Sizes:
I assume you do use auto layout. If you don’t yet, please consider using it since it make life much easier!
If you use a UITableView, you can adjust the height of its UITableViewCells dynamically, depending on the actual content by using self-sizing cells. You can find a tutorial how to do this here.
Variable TextView Positions:
I assume you have a UITextView within a table view cell. In this case, you have to set auto layout constraints to the borders of the cell’s contentView. If you define a custom subclass of a UITableViewCell, you can define in this class 2 IBOutlet properties that are linked to say the left and the right layout constraints (e.g. var leftLayoutConstraint: NSLayoutConstraint). Then, you can set the constraint’s constant property as required when the cell is laid out, i.e. in the layoutSubviews function of the custom table view cell.
Non-selectability:
I am not sure what you mean by „I can simply not implement this“. Please make sure that you set the delegate property of the UITableView to the view controller where you want to handle cell selection. Selecting a cell changes the cells color by default, but you can change this: In the storyboard, select your table view’s prototype cell, and open Xcode’s utility pane (top rightmost button). Under „Table view cell“ you find „Selection“ that you can set to „None“.
I hope this helps!
I am new to Windows Phone Programming. In my application, I Have a listbox which lists the phone contacts. Currently it is listed as a regular list with equal size for list items in the UI.I am looking to modify the front end like this :
I dont want to have different sizes /back ground color for each list items rather a fixed UI and let the lists scroll through it and the list item in the view, at any time, should be displayed as in the picture.
I dont expect any codes as answers but any examples are welcome too, just want to know using what feature this kind of functionality is possible so that i can do my reading!
Thanks,
Deepak
It would be difficult to modify an existing control (ListBox for example) to act like this, so your best bet would probably be an ItemsControl with its RenderTransform set as a TranslateTransform.
If you place a Rectangle (with Fill="Transparent") over the ItemsControl, you can attach handlers to the ManipulationStarted, ManipulationDelta, and ManipulationCompleted events to control the "scrolling" by setting the TranslateTransform's Y offset.
To resize the items in the list there are two options: a custom panel or manual setting.
Custom Panel
You could create a custom Panel implementation that will appropriately resize its Children based on a property you would create to represent the scroll position. Set the ItemsControl to use your panel, and either through binding or attaching a handler to the panel's Loaded event and keeping a pointer to the panel, update the aforementioned property from inside the ManipulationDelta handler.
Manual Setting
From inside of the ManipulationDelta handler, you can also calculate the various heights of the boxes and use MyItemsControl.ItemContainerGenerator.ContainerFromIndex to get the visual for each item and set its height.
I would suggest putting this all inside of a custom UserControl.
You may have issues with clipping using the TranslateTransform but hopefully this will get you started. Unfortunately, this looks like a rather difficult control to try making as your first windows phone project!
So Finally I did manage to find a way to do it.
First approach was as #Murkaeus suggested, Using UserControl and ManipulationDelta event handler. However for some reason the manipulationDelta event was triggered only for 2 finger gestures (Zoom, Pinch..etc), I have no clue why. And after some trying I had to give up on this.
The next approach was using Listbox itself. The source of the Listbox was set as the List( of Models objects) that I create after reading the contact information from phone. The height and color of the listbox item was bound to a property in my model named "scaleLevel" and was accordingly converted by implementing IValueConvertors to give predefined color and height values for different scale levels.
I created an attached property for the scrollviewer vertical offset like mentioned [here] (http://www.scottlogic.co.uk/blog/colin/2010/07/exposing-and-binding-to-a-silverlight-scrollviewer%E2%80%99s-scrollbars/)!
This event is triggered on change of the vertical offset and every time there is a scroll, I find out which listbox item to be enlarged and which reduced based current vertical offset.
Once I have this information, I change the property ("scaleLevel") of the affected items in the List (of Model) (which is bound to listbox height and color). This change is updated in UI using the INotifyPropertyChanged Event.
I have no idea if this the best way of doing it , but it works well and there is no considerable in updating the UI despite the processing involved.
I would like to hear your opinion about the implementation and any other solution which you feel will work better.
I have a table that the user should not be able to edit directly (although user actions may cause changes). One column may contain a string too long for any reasonable size cell, so to see everything there, the user needs to scroll the cell (using arrow keys, for example).
If I make either the column or cell not editible, I loose the ability to scroll the cell.
If I make it editable, of course, I loose the ability to keep the user from changeing it.
(I'm using NSArray controller and a couple of NSObject controllers to get from the model to the table view using bindings. Binding compliance via #property(copy) and #synthesize. Updating the model with setXXXX:xxx).
Thanks,
John Velman
What's wrong with letting the table display tooltips for overflowed contents? This is automatic as of 10.5 if I recall correctly, else you can use the delegate method -tableView:toolTipForCell:rect:tableColumn:row:mouseLocation: for better control.
I want to build a Cocoa App with a list of entries very similar to the ToDo list of Things.app (see the screencast). The question is whether I should use
a TableView,
a CollectionView or
a WebView.
I think it could work with all of them, but which one suits the following requirements best?
have a list of entries -> 1 column & many rows
reordering with drag & drop
select single entries & use keys for actions like delete
open up an entry: the row should expand to show more input fields
customized look: rounded corners, shadow, background gradient
So far my research says that the TableView has most of the functionality, but is harder to customize in its appearance, the CollectionView doesn't have drag & drop (right?) but is easy to design and the WebView would take much effort to not hurt the user experience and I can't bind my model directly to input fields.
What pros and cons am I missing and what would you recommend to use?
A WebView doesn't make sense. You might as well create a web application if you use a WebView. An NSCollectionView is more for grid like data, like TV listings per hour.
NSTableView is the only one that makes sense in this case. I've implemented all 5 bullet points with with an NSTableView without issue. You need to extend NSTableView and do some custom drawing for the customized look. That's the hardest part.
open up an entry: the row should expand to show more input fields
You need an outline view. A table view is for flat lists.
Note that NSOutlineView is a subclass of NSTableView, so all the table-view features work on an outline view as well.
There are people who've done this already. One that I've used successfully is by Matteo Bertozzi and is available here: http://th30z.netsons.org/2009/03/cocoa-sidebar-with-badges-take-2/ It might take a bit of massaging to get it to work properly (especially if you need complex drag-and-drop behavior), but for basic functionality, such as getting the section titles and items in the list, it works excellently.
Edit: This has come up before and is a common question on the cocoa-dev email list. Here are some other options.
Just took a look at Things.app itself using "F-script anywhere".
They've used a subclass of NSTableView called "DetailTableView" which presents the condensed todo items. Collapsed todo items are implemented using a custom cell called "ToDoCell", but the expanded look you get when editing is interesting. In that case they've got a custom view called "ToDoEditView" which is inserted as a subview of the DetailTableView when required. I suspect this editing view is temporarily added as a subview in the correct location and the corresponding row of the tableview gets resized temporarily while it is present.
All pretty speculative .. I'd love to know the details of how this was done. It's an awesome UI.
I'm approaching the very same problem in my app (with one big list similar to the Things todo list) and I think a table view would make a lot of sense here.
The trick is having your cells ("rows") expand when double-clicked. That's about all the progress I've made so far.
I am trying to give a ListBox drag and drop ordering functionality and I have hit a wall. I got it to work when I specify the list box items in xaml but it does not work when I bind to a list it no longer works because the items are no longer of a listboxitem type.
I found this code http://blog.dobaginski.com/josh/?p=52 that allows me to get the underlying ListBoxItem but I can't get the mouse move event to fire.
I have went through other tutorials but have not been able to find one that deals with a ListBox. Has anyone done this with a ListBox.
The events I am using are SelectedChange, MouseMove, and LeftMouseButtonUp (I think that name is right). I am not using LeftMouseButtonDown because I couldn't get it to fire.
As far as i know you cannot get at the listbox item container when using data binding. YOu could in Beta 1.
You also cannot set a mouse event handler in the style, you must use a data template, just so you know.
You will likely have to use the mouse move event from a parent element, probably the UserControl or main layout control that hosts the listbox.
State changes and animations need to be in the style though so... you still cant get at the listbox item, just the element inside it in the data template.
Oh and if doing drag and drop HitTest is now protected so that will make the Drop harder.
since today you can download the final 2.0 version of Silverlight with some add ons, check the Scott's web log
I've been trying to do the same thing in WPF,
but have only found many buggy implementations.
One person has guided me towards the blog of Beatriz Costa,
and from what I remember she's one of those rare geniouses,
so I suggest you read that as well... I know I will
Blog of Beatriz Costa