I am building my custom UIControl, a custom button built as an IBDesignable, which needs to change based on the size class in which it is being displayed. I have a method -setupForTraitCollection, which looks like this:
func setupForTraitCollection() {
switch(traitCollection.horizontalSizeClass, traitCollection.verticalSizeClass) {
case (.Regular, _):
// iPad - not compressed design
compressed = false
default:
// iPhone - compressed design
compressed = true
}
}
This code works great when compiled, but in live rendering, and when debugging the view, it never hits the "iPad" switch case. I am starting to give up here and simply accept that traitCollections aren't available in live rendering, but I'd like to have this confirmed. Better still, if someone could point me in the direction of finding a solution.
So the to-the-point question is - Can I use traitCollections in an IBDesignable and if so, how?
I'd really like to be able to change size class in IB and see the result on my custom control.
Interface Builder does not yet set the trait collection for designable views when we are rendering in Xcode. We are tracking this with radar://17278773. Filing a report at http://bugreport.apple.com and mentioning that bug ID will help us track demand and prioritize appropriately.
Related
I have this using wix/react-native-navigation:
static navigatorStyle = {
navBarHideOnScroll: true,
largeTitle: true
}
How can I add a search input (without using navBarCustomView) under the large title? Something like this:
Currently it is not supported.
This feature requires setting a searchController to the navigationItem of the native view-controller. As simple as it might seem, it's actually a bit complicated due to the fact that RNN will need to expose the functionality and API of the native UISearchController. That said, it's possible that it will be added in the future.
I have a UWP application.
And i have a need to change locale on the fly, so i have this for language changing:
Windows.Globalization.ApplicationLanguages.PrimaryLanguageOverride = language.FourDigitCode;
ResourceContext.GetForViewIndependentUse().Reset();
ResourceContext.GetForCurrentView();
But there is a problem that system features language doesn't switch ( only after application relaunch ) how can i fix it?
Here is an example:
Now i run this code:
Windows.Globalization.ApplicationLanguages.PrimaryLanguageOverride = "lv-LV";
ResourceContext.GetForViewIndependentUse().Reset();
ResourceContext.GetForCurrentView();
The UI gets localized, but system features still remain unlocalized:
But when i restart the app, all is OK:
Any ideas how can i fix it?
I'm afraid there is no fix for this and what you've seen is by design. Ref Remarks of PrimaryLanguageOverride property:
When you set the PrimaryLanguageOverride, this is immediately reflected in the Languages property. However, this change may not take effect immediately on resources loaded in the app UI. To make sure the app responds to such changes, you can listen to the QualifierValues property on a default resource context and take whatever actions may be needed to reload resources. Those requirements may vary depending on the UI framework used by the app, and it may be necessary to restart the app.
For your scenario, a restart is needed. I'd suggest that you can add a tip to tell users to restart the app and also a button to close the app like what used in News App.
And to close the app, we can call Application.Exit method like the following.
Application.Current.Exit();
Maybe page reloading can fix it? Try to re-navigate to the same page.
Found the example below here.
//like this
private bool Reload(object param = null)
{
var type = Frame.CurrentSourcePageType;
Frame.Navigate(type, param);
Frame.BackStack.Remove(Frame.BackStack.Last());
}
// or like this
private bool Reload(object param = null)
{
var frame = Window.Current.Content as Frame;
frame.Navigate(frame.CurrentSourcePageType, param);
frame.BackStack.Remove(frame .BackStack.Last());
}
My application has deep navigational chains of 8+ screens deep (Wizard-style). When i'm editing a View Controller, and i want to make a quick visual change and re-test, As a tester, I have to go through the full flow to end up where I was before recompiling, in the same Data state. Is there a way that Xcode can somehow preserve the application state, and re-run the same view controller?
If there was an automated way to detect the last launched screen, and re-display it after the recompile, that would save a lot of developers a lot of time.
I realize something like this can be built custom. Something like:
IF A Certain Debug Flag is ON:
- Retrieve from NSUserDefaults the Class Name of the last controller used, and redisplay it.
The problem with this is: Data State and Navigation State will not be preserved. Also, all other object state which invokes and depends on your controller will not be included. That's why I need a more universal solution.
IF A Certain Debug Flag is ON: - Retrieve from NSUserDefaults the Class Name of the last controller used, and redisplay it.
The problem with this is: Data State and Navigation State will not be preserved.
But this is exactly the problem that the built-in state saving and restoration mechanism is intended to solve, is it not?
https://developer.apple.com/library/ios/featuredarticles/ViewControllerPGforiPhoneOS/PreservingandRestoringState.html
I recommend you use a User Interface target and then create an XCTestCase that works on your view controller and exercise it. Use the new record button in Xcode 7 to get you started with the test case. Familiarize yourself with some of the new queries it uses for some of the dynamic information you may be creating.
Another option would be to inject your test case's UI state into the application delegate in the setup function of an XCTestCase. Then it will need custom logic to navigate to the correct view controller. Then your test case could focus on just that ViewController once the Application delegate has navigated to it.
Of course you can use the debugger and breakpoints in the Test Case and your View Controller while UI Testing. By "scripting" this you do significantly less manual clicking on a device to test a ViewCOntroller
Also you've now got a Test! Hopefully worth something to you down the road when you change something
In my Cocoa app, I want to prevent Flash from loading in a WebView, and let the user decide if the Flash should be shown for each page. (That's the same behavior already available through the ClickToFlash plugin or Safari extension. Bundling any of those extensions is probably not an option because of licensing issues.)
Unfortunately most of the Flash I'm trying to avoid is generated from embedded JavaScript specifically designed to prevent easy flash blocking, so I cannot filter the raw HTML for inclusion of Flash objects.
Also, I cannot disable JavaScript for my WebView, as the page I want to display looks completely different when JavaScript is turned off.
Is there a notification/hook I can use to modify the page DOM after JavaScript has been executed, but before the Flash plugin is loaded?
Or should I pursue a different direction?
Thanks,
Ilja
Ideally, you would just define your own WebKit plug-in that handles the application/shockwave-flash MIME type and make your plug-in do nothing.
However, there is unfortunately no way to control the priority of multiple WebKit plug-ins that all register for the same MIME type. The loading order of WebKit plug-ins is totally random and arbitrary, so you cannot guarantee that your plug-in will handle the Flash object instead of the Flash plug-in.
The only way around this that I've found is to subclass WebView and override the private method -_pluginForMIMEType: like so:
#class WebBasePluginPackage;
#interface WebView ( MyFlashPluginHack )
- (WebBasePluginPackage *)_pluginForMIMEType:(NSString *)MIMEType;
#end
#implementation MyWebView
- (WebBasePluginPackage *)_pluginForMIMEType:(NSString *)MIMEType
{
if ( [MIMEType isEqualToString:#"application/x-shockwave-flash"] )
{
return [super _pluginForMIMEType:#"application/my-plugin-type"];
}
else
{
return [super _pluginForMIMEType:MIMEType];
}
}
#end
Then you just need to create a custom WebKit plugin to handle "application/my-plugin-type" and have that plug-in do nothing at all.
Okay, we pretty much figured this out.
Since there is no official API that lets the host app know when JavaScript has finished or control what plugin should load, we are now using custom JavaScript that gets inserted into the received HTML we want to display.
The ClickToFlash Safari extension (not the Internet plugin, which it is based on) was a good inspiration.
In .NET I just do something like DataForm.Source = Object and then magic happens. Platform routes data changes from ui fileds to object properties, does validation and so on. Can I do something similar with Cocoa Touch and CoreData objects?
The closest thing in Cocoa is 'Key-Value Observing'. In the desktop Cocoa framework you can use bindings to hook user interface elements up to underlying objects so that changes in the objects or UI elements are reflected in the other.
Whilst Cocoa on iOS doesn't have this sort of UI bindings, you can still use 'Key-Value Observing' to synchronise changes in the data model with UI elements as described here:
http://developer.apple.com/library/iOS/#documentation/General/Conceptual/Devpedia-CocoaApp/KVO.html
I wrote a little open-source library that provides some simple data-binding functionality. It's basically just a wrapper around key-value observing (KVO).
http://github.com/kristopherjohnson/KJSimpleBinding
There are a few other similar libraries on GitHub:
http://github.com/dewind/KeyPathBindings
http://github.com/jonsterling/Observe
http://github.com/mruegenberg/objc-simple-bindings
http://github.com/zeasy/EasyBinding
Probably should also mention Github's Reactive Cocoa, a framework for composing and transforming sequences of values, an objective-C version of .NET's Reactive Extensions (Rx).
Binding mechanics can be done really simple (from the sample):
// RACObserve(self, username) creates a new RACSignal that sends a new value
// whenever the username changes. -subscribeNext: will execute the block
// whenever the signal sends a value.
[RACObserve(self, username) subscribeNext:^(NSString *newName) {
NSLog(#"%#", newName);
}];
Don't forget NSFetchedResultsController.
Not a full blown data bound controller, but makes table views a lot easier to use with Core Data.
If you're using Swift, check out Bond framework: https://github.com/ReactiveKit/Bond
Binding is as simple as:
textField.reactive.text.bind(to: label.reactive.text)
It plays well with functional:
textField.reactive.text
.map { "Hi " + $0 }
.bind(to: label.reactive.text)
And provides simple observations:
textField.reactive.text
.observeNext { text in
print(text)
}
STV (http://sensiblecocoa.com) is a framework that can do that within tableviews
I use CoreDataTableViewController from the Stanford University for my TableViewControllers. It hides a lot of details that you would normally implement in your TableViewController.
Googling for CoreDataTableViewController.h and .m will help you on the road. There are versions from several courses available, the latest does ARC, the old ones don't.
For syncing labels and edit fields with an NSManagedObject, I am still looking for a good solution.
Yes, there is a data binding framework that integrates well into Interface Builder and requires only minimal code overhead (if at all).
Take a look at https://github.com/mutech/aka-ios-beacon
EDIT:
You can for example bind a table view to a fetched results controller simply by setting the data source binding property of the table view in interface builder to:
[ yourResultsController ] { defaultCellMapping: "YourCellId" }
And the only thing you have to do is to define a property yourResultsController in your view controller.
The wiki provides a rather complete documentation and a lot of example use cases.