Interface Builder Outlets. Where can I find them? - xcode4

I can create an Outlet from a ViewController to a View by Ctrl Drag between viewcontroller bar button and the view.
It appears in the context view of the ViewController Bar button.
Where does the outlet created like this appear in code? (or doesn't it?).
The problem I am having is that when I make an Outlet from a view to its controller I sometimes (frequently?) find the pop up choice does not include my View. In other words if I made a view called picView I should see picView as a choice along with view but I only see view.
Later, I find my delegate ViewController methods will not run. When I go back to make the link again, I find mysteriously that my view is now an option and that fixes the issue.
Here are two pictures that illustrate the issue.
Here there is no link available
Here there is a link available

Having gone through the process of creating an App specially to illustrate this point I have discovered that I was looking the wrong way round. Rather than Interface Builder Creating the Outlet I have to put it into the ViewController and then IB can use it to make the link.
This is achieved when I put the outlet into the interface of the ViewController.m file illustrated below. At that moment, the link appears in IB.
//
// SecondViewController.m
// Empty Test
//
// Created by Brian Lockwood on 07/09/2012.
// Copyright (c) 2012 __MyCompanyName__. All rights reserved.
//
#import "SecondViewController.h"
#import "PicView.h"
#interface SecondViewController() <PicViewDataSourceDelegate>
#property (nonatomic, weak) IBOutlet PicView *picView; //<<<<<<<<< this line here
#end

Related

Qt shortcut for custom context menu

I have been reading though a couple of examples and post but I just cannot figure out how to add a shortcut to my custom context menu. My GUI has several elements. One of them is a treeView. For the elements in my treeView I would like to have a custom context menu.
My first approach was according to this tutorial here. The context menu itself worked but the shortcuts cannot work if you create the actin within the show function.
So my second approach was according to this tutorial. But still my shortcuts do not work and if I use the context menu all actions are called twice...
Since I did not find a tutorial or code example, which matches my case, I hope that someone here can explain to me how this is correctly done in theory. Adding a shortcut to an action for a custom context menu.
Where do I have to declare my action?
What needs to be the parent of the action?
On which widget do I need to call addAction?
Thanks for any hints.
Another way is to add your action also to the parent widget (or main window widget). As mentioned in this reply, adding the same action to multiple widgets is fine and it's the way QActions are supposed to be used.
Example with custom HtmlBrowser class deriving from QTextBrowser:
Ctrl+U shortcut works for this code:
HtmlBrowser::HtmlBrowser(QWidget * parent) : QTextBrowser(parent)
{
viewSourceAct = new QAction(tr("View/hide HTML so&urce"), this);
viewSourceAct->setShortcut(tr("Ctrl+U"));
viewSourceAct->setCheckable(true);
parent->addAction(viewSourceAct);
connect(viewSourceAct, &QAction::triggered, this, &HtmlBrowser::viewSourceToggle);
}
and Ctrl+U shortcut does not work with this code (same as above, but without parent->AddAction(...)):
HtmlBrowser::HtmlBrowser(QWidget * parent) : QTextBrowser(parent)
{
viewSourceAct = new QAction(tr("View/hide HTML so&urce"), this);
viewSourceAct->setShortcut(tr("Ctrl+U"));
viewSourceAct->setCheckable(true);
connect(viewSourceAct, &QAction::triggered, this, &HtmlBrowser::viewSourceToggle);
}
Curiously, parent in this case is another widget (tab widget), not MainWindow. Still, adding parent->addAction() helps. And, unlike your suggested answer, it works even when connecting action to simple methods, without slots. Works for me in Qt 5.15.0. Not quite sure why it works, though. Perhaps, the widget the action is added to must be permanent for shortcuts to work? Looks like a bug in Qt.
Thanks to Scheff's hint I got it working. I do not now if this is really the correct way but this works for me.
The action needs to be declared in the constructor of your GUI class (e.g. MainWindow):
actionDel = new QAction(tr("delete"), this);
actionDel->setShortcut(QKeySequence(Qt::Key_Delete));
connect(actionDel, SIGNAL(triggered()), this, SLOT(actionDel_triggered()));
The triggered signal needs to be connected to a slot. Hint: if you create the slot do not use on_ACTIONNAME_triggered, this will interfere with the designer and cause a connection error.
Next add the action to a custom menu
fileContextMenu = new QMenu(this);
fileContextMenu->addAction(actionDel);
And to the widget
ui->treeView->setContextMenuPolicy(Qt::CustomContextMenu);
connect(ui->treeView, SIGNAL(customContextMenuRequested(QPoint)), this, SLOT(showDirContextMenu(QPoint)));
ui->treeView->addAction(actionDel);
All in the constructor of your GUI class.
To show the context menu use the following code in slot used in the above connect:
QModelIndex index=ui->treeView->indexAt(pos);
// Here you can modify the menu e.g. disabling certain actions
QAction* selectedItem = fileContextMenu->exec(ui->treeView->viewport()->mapToGlobal(pos));
If you do not have a slot for an action, the action can be also handled in the context menu slot, but this does not work with shortcuts!
if(selectedItem == actionOpen){
on_treeView_doubleClicked(index);
}

Linking Storyboards Without UINavigationController

I have an iOS 6 app that I am updating to work with iOS 7 and to make it use storyboards. I am trying to use multiple storyboards so that I can break my project down into modules for each screen in the app. So far this has worked out fine but now I need to provide a way to navigate between the various storyboards while still making the work like it did in iOS 6 (but with updated artwork).
I don't use UINavigationController in my existing iOS 6 app and I would prefer not to use it as up to now I have been able to navigate back and forth between XIB's using code on UIButton tap gestures. The UINavigationController doesn't make it easy to customise how the navigation buttons look from what I have learned so far about it.
I found this very clean way of moving between view controllers that are on different storyboards https://github.com/rob-brown/RBStoryboardLink by passing the name of the storyboard in as an attribute.
But it only seems to work when UINavigationController is used. I get an error "Push segues can only be used when the source controller is managed by an instance of UINavigationController" without UINavigationController.
Is there a way to navigate between storyboards by only using the above RBStoryboardlink but without the need for UINavigationController?
Push segues can only be used when the source controller is managed by an instance of UINavigationController
This means you are trying to push a view controller to the source while source don't have any navigation controller stack.In that case, you should try to add the instantiated view controller's view as subview to the source view controller's view.
UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:#"Main" bundle:nil];
UIViewController *viewController = [mainStoryboard instantiateInitialViewController];
[self.view addSubview:viewController.view];
or you modally present, that purely depends on your requirement.
UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:#"Main" bundle:nil];
UIViewController *viewController = [mainStoryboard instantiateInitialViewController];
tabBarViewController.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
[self presentViewController:tabBarViewController animated:NO completion:NULL];

Next and previous control button in winAPI to go to next page (c++)

I am creating an winAPI application in c++ I have a photo in preview pane and I want to create two buttons NEXT and PREVIOUS on clicking them I will go to the next page .
Could you please give me the idea how to do that in c++ ??
Do I need to use QT libraray or it can be done using the in built function of WinAPI like -
HWND hwndButton1 = CreateWindow(L"BUTTON",L"NEXT",WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON,550,800,100,30,m_hwndPreview,(HMENU)buttonid1,(HINSTANCE)GetWindowLong(m_hwndPreview, -6),NULL);
HWND hwndButton2 = CreateWindow(L"BUTTON",L"PREVIOUS",WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON,650,800,100,30,m_hwndPreview,(HMENU)buttonid2,(HINSTANCE)GetWindowLong(m_hwndPreview, -6),NULL);
and then using WM_COMMAND for both the button clicks.
Am I going right?
I just want my API application work like a .pdf extension file...as in PDF files we have up and down arrow and on clicking upon them we can go to the next page..In winAPIc++ I couldn't find any such arrow function.. please tell me if there is any such arrow up/down function present to go to next page (because I am very less interested in creating NEXT and PREVIOUS button using createwindow function.. It looks odd).
You have not mentioned what tools you are using, so we don't know if you have a resouce editor. You should research that in a forum appropriate for the tools. If you think writing one line of code to create a button is "very complicated" then you need a better tool.
If you do not want the buttons to appear on top of the picture then you need another place to put them. One common possibility is a toolbar. It is a strip for buttons along the top or bottom of the main window:
http://msdn.microsoft.com/en-us/library/windows/desktop/bb760435(v=vs.85).aspx
With a resource editor you can draw an arrow on the button. Without a resource editor you can set the button text to a unicode arrow:
SetWindowText(hwndButton1, L"\x25bc"); // down arrow, use 25b2 for up arrow
Most buttons (and other controls) are created using a resource editor, placing the controls on a dialog template or a toolbar resource. If you do that Windows will create the buttons when you create the dialog or toolbar. This method is much preferred because Windows will adjust the size of the buttons as required for the screen settings in use.
If you can't do that you must use CreateWindow as you are doing.
Finally it is done.. I have created the buttons neither using Qt or nor using any createWindowEx..The best and easy approach to follow is resource editor ...just put some button on dialog and use IDD_MAINDIALOG (in my case)
m_hwndPreview = CreateDialogParam( g_hInst,MAKEINTRESOURCE(IDD_MAINDIALOG), m_hwndParent,(DLGPROC)DialogProc, (LPARAM)this);
and then
BOOL CALLBACK AMEPreviewHandler::DialogProc(HWND m_hwndPreview, UINT Umsg, WPARAM wParam, LPARAM lParam)
{
switch(Umsg) // handle these messages
{ .........
}
....
}
and thats done. Very easy task.

Unable to get html file to display in UIWebView

I am attempting to follow this example: http://howtomakeiphoneapps.com/uiwebview-tutorial/239/
I have added a UIWebView into my view (using Storyboard)... I added the IBOutlet to my .h controller file. (see image at: http://imgur.com/GfUmC). I added a delegate to the view controller like this:
#import <UIKit/UIKit.h>
#interface slWebViewController : UIViewController <UIWebViewDelegate> {
IBOutlet UIWebView *slWebView;
}
#end
Since I'm using XCode 4, I don't know how to set the UIWebView's delegate to the File Owner, which is why I think this is what I'm getting a black screen. I'm missing something, but I don't know what. At this point, I would really, really appreciate any help I can get solving this...
In your Storyboard, right click (or ctrl-click) and drag from your UIWebView to the File's Owner on the left side, and choose "delegate".
Alternatively, select the webView (as in your image). Note the top outlet, "delegate". Drag from there to the File's Owner.
Or you can code it. In viewDidLoad, type "self.sIWebView.delegate = self;"
All of this is assuming that you have your URL request right. In case you don't, here's an example:
NSURL * url = [NSURL URLWithString:#"http://google.com"];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL: url
cachePolicy: NSURLRequestReloadIgnoringCacheData
timeoutInterval: 10];
[sIWebView loadRequest:request];
EDIT: If you are presenting the webView modally, add this code to the view controller that segues to your webview: -(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{ if ([segue.identifier isEqualToString:#"SegueIdentifier"]) { WebViewController *webView = segue.destinationViewController; webView.delegate = self; } } You'll need to add an identifier to your segue. Just click on the segue itself, go to the third tab from the right, and type in an identifier.
UPDATE: I've isolated the problem to the webViewConroller.m file. Everything is connected properly. If I place the loadRequest code in the viewController at viewDidLoad, I see Google. If I place the loadRequest code in the "webViewController", and mark the ViewContoller as a custom class of webViewController, I get the black screen. I'm wondering if there isn't a better way to get the UIWebView to display content? I really don't need a controller for the webView, just when the segue for that cell is tapped, display the contents of the UIWebView... not sure I can do it with XCode...

Assigning an NSView to a window's contentView in the NIB

I am doing an exercise that assigns a view programmatically, but in which the author says, "We could do this in IB, but let's do it in code".
Here is the setUp.
1) 2 nib files, one "MainMenu" , the other an "ActivityView" nib. In this case, the "MainMenu" nib contains the Window and the contentView. The "ActivityView" contains a view, whose file's Owner is a subclassed NSViewController, which is instantiated in the "MainMenu" nib.
The other thing is that the AppDelegate contains an IBOutlet to the "ActivityView" object in the MainMenu nib file.
So, programmatically, in the "applicationDidFinishLaunching" (of the AppDelegate), the code that is used, and works is:
self.window.contentView=ac.view // where ac is an NSViewController Subclass
I would like to understand how to do this in the IB, but have been unable to do so. The closest was a suggestion to copy and paste the view from the 2nd nib, ( which works) but does not seem elegant, or perhaps this is the way it is done. Connecting the view outlet of the ActivityController ( i.e. the owner of the ActivityView's nib) in the MainMenu nib to the view of the window, does not work. There is a good chance I am not asking the correct question, so would appreciate some insights into what the issue is that I am missing.

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