chore: add CF functions for using bookmark data
fixes#116 (a closed issue)
Provides the definitions for some of the CF functions for using Bookmark data (which is useful for sandboxed applications).
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chore: add simple NSControl class
I needed to use `[button setEnabled]` for an `NSButton`, so I added some of `NSControl`'s basic functionality.
Example usage:
```rust
use cocoa::foundation::NSRect;
use cocoa::appkit::{NSButton, NSControl, NSView};
// Parent view
let view = NSView::alloc(nil)
.initWithFrame_(NSRect::new(NSPoint::new(0., 0.), NSSize::new(200., 200.)));
// Add button to view
let button = NSButton::alloc(nil)
.initWithFrame_(NSRect::new(NSPoint::new(20., 20.), NSSize::new(150., 50.)));
NSView::addSubview_(view, button);
// Prints "1" (button enabled)
println!("{:?}", NSControl::isEnabled_(button));
// Disable the button
NSControl::setEnabled_(button, NO);
// Prints "0" (button disabled)
println!("{:?}", NSControl::isEnabled_(button));
```
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Converting between dictionary types
I'm trying to use the `CFDictionary` and `CFMutableDictionary` types more extensively. But run into problems. They are not very compatible with each other. This crate for example does not expose any clean way of using `CFDictionaryCreateMutableCopy` to create a `CFMutableDictionary` from any `CFDictionary`. I added a `From` implementation for this.
It was not possible to, in some safe/simple way, cast a `CFDictionary<K, V>` into the untyped `CFDictionary<*const c_void, *const c_void>` something I added `to_untyped` to be able to do.
When it comes to downcasting, it was not possible to downcast a `CFType` into a dictionary, since they don't implement `ConcreteCFType`. Something they probably should, for the case where the keys and values are just void pointers. `CFArray` does exactly this.
Lastly, what I needed the most was to be able to convert a `CFMutableDictionary` into a `CFDictionary`. This allows me to borrow an immutable `CFDictionary` via the `ItemRef` type basically. It's possible to work around this and actually have owned instances of a `CFDictionary` and a `CFMutableDictionary` pointing to the same actual dictionary by doing this:
```rust
let mut_dict = CFMutableDictionary::new();
let mut_dict2 = mut_dict.clone();
let dict = mut_dict.as_immutable();
// Here one can mutate the dict via `mut_dict2` while `dict` is still in scope/alive.
```
But since we already allow cloning a `CFMutableDictionary` to have two mutable references to the same dictionary I guess someone decided this should be viewed as safe. Both `CFDictionary` and `CFMutableDictionary` does not implement `Send` so we should not end up in any actual thread inconsistencies here.
If the above is indeed considered safe, I could get rid of the `ItemRef` juggling and just make it `fn as_immutable(&self) -> CFDictionary` directly maybe? Would simplify usage.
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Add constants for new AppKit versions through El Capitan.
I need this to fix `winit`, because Mojave has some new behavior around
layer-backed views and version sniffing is the easiest way to detect when I need to handle it.
This also bumps the version to 0.18.3.
r? @jdm
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I need this to fix `winit`, because Mojave has some new behavior around
layer-backed views and version sniffing is the easiest way to detect when I
need to handle it.
This also bumps the version to 0.18.3.
bors-servo
