How to select an item of combobox when pressing a key - objective-c

I have a combo box with a array of items in string. After i click the arrow to show all the items, i want when i press a key which represent first letter of a item then the respective item will be selected (item is highlighted and NSComboBoxSelectionDidChangeNotification is posted). TextField of combobox is set to not be editable in this case.
I'm new to cocoa and objective and I don't know how to implement this.
I try to implement all methods of NSComboBoxDataSource protocol but the item is highlighted without any notification when i input text to textfield of combobox which is then editable (just a try because i want it isn't editable).
Any suggestion would be appreciated.

Related

Object reference in vb. Net when clicking icon

I have a panel that fills with icons of characters. I have a second panel I would like to fill with icons from which character is selected. What is the best way to know which character was selected? Both panels are flow layout panels. I can hover over the character and display the name but I need a good way to reference which character is clicked. The entire object is a user control and another object that retrieves the champion icons to fill the first panel. Thank you.
You need to handle the form.KeyPress event.
Control.KeyPress Event
Examine the KeyEventArgs and go from there.

OSX: Move keyboard focus between textfields and buttons using tab key

I am trying to toggle between textfields and buttons on my view using keyboard's tab button. The switching between textfields work but it does not switch between buttons. The view is shown as below.I did not find enough resources online to proceed further. Does anyone know how to resolve this?
There is nothing you can do with that issue.
It turns out that in the System Preferences > Keyboard > Shortcuts there is a checkbox, where you can change behaviour of the whole system:
To move keyboard focus only between text boxes and lists
To move keyboard between any of controls
And by default first checkbox is pressed.
As an addition. By default, NSWindow assigns an initial first responder and constructs a key view loop with the objects it finds. You can also change key view loop by calling this method: setNextKeyView.
For example,
[firstTextBox setNextKeyView:secondTextBox];
[secondTextBox setNextKeyView:secondButton];
[secondButton setNextKeyView:firstButton];
[firstButton setNextKeyView:firstTextBox];
This means that for users who expect moving control focus through all controls, this will work. And for those who have disabled this feature in settings, this won't work.
You can right-click on text field, drag "nextKeyView" and drop on another text field that you want to focus next when user press tab. Look like my picture below:
To add to #mjonka's answer, To move focus between controls is dependent on user's keyboard-shortcuts settings. What could be alternate solution is to just selecting your desired action button in your xib file and setting "Key Equivalent" value field to "enter" key in Attributes inspector as shown below. Same thing can be done for cancel button by setting "Key Equivalent" value to "Esc" key.

Scroll automatically to a control inside scrollviewer

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?

vb.net winforms datagridview how to tell where the user clicked in a cell

I am adding a custom column to a custom datagridview. One of the options this new datagridcolumn has is the ability show a value and then a button to allow the user to click on the button and something will happen. The button only takes up the right portion of the cell and the rest is a value. This button and value are displayable always and the button should always be able to be clicked on. In datagridview's display mode the value and button are painted. What I need help on is how to tell whether the user clicked on the button portion of the cell. Can someone please provide example code on how to do this?
Thanks,
Greg
Never mind I figured it out. I just put some logic in the cellclick event of the datagridview to get the GetCellDisplayRectangle and converted that to screen points and got where the mouse is on the screen and did a bounds test with the rectangle contains method.

Is there a way to control the NSMenuItem item that is initially highlighted when opening a menu?

I'm working on the details of a symbols pop up button, similar to what Xcode 3 at the top of its editor window.
My controller object is the delegate of the NSMenu that is shown when the NSPopUpButton is shown. I implement the two methods numberOfItemsInMenu: and menu:updateItem:atIndex:shouldCancel: to populate the menu right before it's about to be displayed.
However, the title and image of the selected NSMenuItem have to change each time the user changes the selection in the editor NSTextView, or makes changes to the text; just as is the case with Xcode.
The problem I'm having is when the user goes to click on the NSPopUpButton to display the NSMenu, the selected NSMenuItem and the item that should be selected do not match up, since the menu doesn't have the proper number of items yet.
I'm wondering if there is a way to control which NSMenuItem is initially highlighted and tracked when the user clicks to open the menu. As it stands, the first item it always highlighted and tracked or, if the user had previously selected a item, that item is highlighted and tracked.
I tried explaining as best I could, but here is a image illustrating my problem:
I want the highlighted item to be the same as the selected item when the user opens the menu. Any ideas?
I would use a NSPopupbutton - it can do what you want. maybe you even hide it?
I am not very sure that I understood your problem but If we can add tags to these menu Items.
e.g.
[mMenuItemOne setTag : 1];
[mMenuItemTwo setTag : 2];
[mMenuItemThree setTag : 3];
[mMenuItemFour setTag : 4];}
we can select any Menu item using
[_popUp selectItemWithTag: _selectedItem];
Just a hint not a full solution.
Try to post an NSMouseMoved event to your app right after the menu shown.
Main problem is here to detect the position of the item you want to be highlighted.
Just a starting point.
Have you tried this NSMenuDelegate method:Handling Highlighting
– menu:willHighlightItem:
NSMenuDelegate Protocol Reference
Also you can store the NSMenuItem index in some var to keep track of the selected item for later use.
I'm not sure, do you want to move the mouse selection highlight (the blue stuff) or the checkmark?
In general, the checkmark is the thing you want to change. You can do so from your validateMenuItem: method (or at any other time if your item is set not to take part in validation) using the -setState: method.
The blue highlight is an indicator of the user's keyboard input or mouse location, and you should not mess with it. Changing it does not make any sense, as it would be changed back the moment the user moves the mouse even a single pixel.
That said, you can set the selectedItem of the NSPopUpButton, which will cause the entire menu to be moved so the selectedItem is under the mouse (assuming the mouse just clicked the popup button).
If your menu delegate method is called after the pop up button has decided what item to select, you can't use it. Instead, you could probably set the selectedItem and menu of the popup button from a NSPopUpButtonWillPopUpNotification handler.
If that is also called too late, you'll probably have to subclass NSPopupButtonCell and do it in an override of -attachPopUpWithFrame:inView: (I think that's the spot that should also work when you don't click and just hit the space key while the popup button is selected).