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.
Cgdisplaymode extensions
I am writing a tool to change resolution on MacOS. For this I needed, more support for CGDisplayMode methods. I also need support for CGConfigureDisplayWithDisplayMode().
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Allow most CGContext methods to be usable from a immutable reference and expose several more methods
If this is too much to submit at once, please tell me. This is what I've got left to send in and I'm unsure where to break it up more.
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Jan Andre Ikenmeyer
