iMRuby

iMRuby is an engine that acts as a bridge between Objective-C and Ruby(Mruby)

Demo

// objective-c file
@interface MRBViewController ()

@property (nonatomic, strong) MRBContext *context;

@end

@implementation MRBViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    // 执行view.rb
    NSString *scriptPath = [[NSBundle mainBundle] pathForResource:@"view" ofType:@"rb"];
    NSString *script = [NSString stringWithContentsOfFile:scriptPath encoding:NSUTF8StringEncoding error:nil];
    self.context = [[MRBContext alloc] init];
    self.context.exceptionHandler = ^(NSError * _Nonnull exception) {
        NSLog(@"%@", exception.userInfo[@"msg"]);
    };
    
    [self.context registerConst:@"Target" value:self];
    [self.context evaluateScript:script];
    MRBValue *superView = [MRBValue valueWithObject:self.view inContext:self.context];
    [self.context callFunc:@"create_view" args:@[superView]];
    
}

- (void)touchAction:(id)sender
{
    [self.context evaluateScript:@"showAlertView"];
}

@end

# ruby file
require_cocoa "UIColor"
require_cocoa "UIView"
require_cocoa "UIImage"
require_cocoa "UIImageView"
require_cocoa "UILabel"
require_cocoa "UIFont"
require_cocoa "UIButton"
require_cocoa "UIAlertController"
require_cocoa "UIAlertAction"
require_cocoa "UIScrollView"

def create_view(super_view)
    # Clolors
    red = UIColor.redColor
    blue = UIColor.blueColor
    green = UIColor.greenColor
    yellow = UIColor.yellowColor
    white = UIColor.whiteColor
    
    super_view.setBackgroundColor_(white)
    # ScrollView
    bounds = super_view.bounds
    scrollview = UIScrollView.alloc.init
    scrollview.setUserInteractionEnabled_(true)
    scrollview.setScrollenabled_(true)
    scrollview.setFrame_(bounds)
    scrollview.setContentSize_({'width' => bounds['width'], 'height' => bounds['height']+10})
    scrollview.setBackgroundColor_(yellow)
    super_view.addSubview_(scrollview)
    
    scrollview.addSubview_(createLabel("UIScrollView", 40, 20))
    
    # UIlabel
    scrollview.addSubview_(createLabel("UILabel", 40, 64))
    
    label = UILabel.alloc.init
    label.setFrame_({'x' => 200, 'y' => 64, 'width' => 150, 'height' => 50})
    label.setText_("Hello World!")
    label.setFont_(UIFont.systemFontOfSize_(24))
    label.setTextColor_(red)
    label.setBackgroundColor_(green)
    scrollview.addSubview_(label)
    
    # UIView
    scrollview.addSubview_(createLabel("UIView", 40, 120))
    
    blue_sub_view = UIView.alloc.init
    blue_sub_view.setFrame_({'x' => 200, 'y' => 120, 'width' => 100, 'height' => 100})
    blue_sub_view.setBackgroundColor_(blue)
    scrollview.addSubview_(blue_sub_view)
    
    # UIImageView
    scrollview.addSubview_(createLabel("UIImageView", 40, 230))
    
    image = UIImage.imageNamed_("logo")
    image_view = UIImageView.alloc.initWithImage_(image)
    image_view.setFrame_({'x'=>200, 'y'=> 230, 'width' => 100, 'height' => 100})
    scrollview.addSubview_(image_view)
    
    # UIButton
    scrollview.addSubview_(createLabel("UIButton", 40, 340))

    btn = UIButton.buttonWithType_(0)
    ## MRBCocoa::Const::Target is defined in OC
    ## [self.context registerConst:@"Target" value:self];
    ## “self” is the view controller
    ## "touchAction:" action is defined in OC and execute ruby script to show alert
    btn.addTarget_action_forControlEvents_(MRBCocoa::Const::Target, "touchAction:", 1<<6)
    btn.setTitle_forState_("Click to show alert", 0)
    btn.setFrame_({'x' => 200, 'y' => 340, 'width' => 170, 'height' => 50})
    btn.setBackgroundColor_(red)
    scrollview.addSubview_(btn)
end

def showAlertView
    # UIAlertController
    completion = Proc.new {puts "show..."}
    completion_block = completion.to_cocoa_block("void,void")
    alertController = UIAlertController.alertControllerWithTitle_message_preferredStyle_("iMRuby", "Hello World!", 1)
    
    ok_handler = Proc.new {|action| puts "OK..."}
    ok_handler_block = ok_handler.to_cocoa_block("void, UIAlertAction")
    okAction = UIAlertAction.actionWithTitle_style_handler_("OK", 0, ok_handler_block)
    
    alertController.addAction_(okAction)
    
    MRBCocoa::Const::Target.presentViewController_animated_completion_(alertController, true, completion_block)
end

def createLabel(text, x, y)
    label = UILabel.alloc.init
    label.setFrame_({'x' => x, 'y' => y, 'width' => 150, 'height' => 50})
    label.setText_(text)
    label.setFont_(UIFont.systemFontOfSize_(24))
    label.setTextColor_(UIColor.blackColor)
    return label
end

Installation

iMRuby is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod 'iMRuby'

Class UML

Usage

iMRuby usage is like JavascriptCore of iOS. aticle url

Ruby and OC are converted to each other

OC type	Ruby type
nil	nil
NSString	string, symbol
NSNumber	Fixnum, Float, boolean
NSDictionary	Hash
NSArray	Array
NSDate	Time
NSBlock	Wrapper object ruby class MRBCocoa::Block
id/NSObject	Wrapper object ruby class MRBCocoa::Object
class	Wrapper object ruby class MRBCocoa::Klass
CGPoint	specific Hash {'x' => 1, 'y' => 1}
CGSize	specific Hash {'width' => 1, 'height' => 1}
CGRect	specific Hash {'x' => 1, 'y' => 1, 'width' => 1, 'height' => 1}
NSRange	specific Hash {'location' => 0, 'length' => 1}

create `MRBContext` instance

self.context = [[MRBContext alloc] init];

run ruby script

[self.context evaluateScript:@"puts \"Happy Niu year!\""];
# => Happy Niu year!

catch exception

self.context.exceptionHandler = ^(NSError * _Nonnull exception) {
        NSLog(@"%@", exception.userInfo[@"msg"]);
    };
[self.context evaluateScript:@"happy_nui_year(2021)"];
# => undefined method 'happy_niu_year' (NOMethodError)

register constant

[self.context registerConst:@"Niu" value:@"Happy Niu year!"];
[self.context evaluateScript:@"puts MRBCocoa::Const::Niu"];
# => Happy Niu year!

register method

[self.context registerFunc:@"happy_niu_year" block:^NSInteger(int a, int b){
    NSLog(@"start...");
    int sum = a + b;
    NSLog(@"finish...");
    return sum;
 }];
 MRBValue *sum = [self.context evaluateScript:@"MRBCocoa.happy_niu_year(2020,1)"];
 NSInteger niu_year = sum.toInt64;
 NSLog(@"%@", @(niu_year));
# => start...
# => finish...
# => 2021

register method or constant by subscript

self.context[@"Niu"] = @"Happy Niu year!";
self.context[@"happy_niu_year"] = ^NSInteger(int a, int b) {
     NSLog(@"start...");
     int sum = a + b;
     NSLog(@"finish...");
    return sum;
};
MRBValue *sum = [self.context evaluateScript:@"puts MRBCocoa::Const::Niu;MRBCocoa.happy_niu_year(2020,1)"];
NSInteger niu_year = sum.toInt64;
NSLog(@"%@", @(niu_year));

OC invoke ruby method

# ruby.rb
def test_func(str)
    puts str
end

    MRBValue *strParam = [MRBValue valueWithString:@"hello" inContext:self.context];
    [self.context callFunc:@"test_func" args:@[strParam]];

ruby invoke OC object method

// OC .m file
@interface Person : NSObject
@property (nonatomic, copy) NSString *name;
@property (nonatomic, assign) int age;
- (NSString *)say_something:(NSString *)message;
- (void)coding:(NSString *)code finished:(BOOL(^)(NSString *name, int age))finished;
@end
@implementation Person
- (NSString *)say_something:(NSString *)message
{
    NSLog(@"%@", message);
    return [self.name stringByAppendingString:message];
}
- (void)coding:(NSString *)code finished:(BOOL(^)(NSString *name, int age))finished
{
    NSLog(@"I am coding %@", code);
    if (finished) {
        BOOL f = finished(self.name, self.age);
        NSLog(@"Block return value: %@", @(f));
    }
}
@end

# ruby .rb file
require_cocoa 'Person'

person = Person.alloc.init
person.setName_('anan')
person.setAge_(2)
message = person.say__something_("happy Niu year!")
puts message

finished = Proc.new {|name, age| puts "I am #{name}, #{age} year old"; true}
finished_block = finished.to_cocoa_block("BOOL, NSString *, int");
person.coding_finished_("Ruby", finished_block)

invoke OC method rules:

replace ':' with '_'

- (NSString *)saySomething:(NSString *)message;
message = person.saySomething_("happy Niu year!")

replace '_' with '__'

- (NSString *)say_something:(NSString *)message;
message = person.say__something_("happy Niu year!")

if '_' or '__' is in the head of oc mehtod name, do nothing

- (NSString *)__say_something:(NSString *)message;
message = person.__say__something_("happy Niu year!")

if oc method has a NSBlock parameter, can use to_cocoa_block to convert Proc to NSBlock

- (void)coding:(NSString *)code finished:(BOOL(^)(NSString *name, int age))finished;

// ruby
finished = Proc.new {|name, age| puts "I am #{name}, #{age} year old"; true}
finished_block = finished.to_cocoa_block("BOOL, NSString *, int");
person.coding_finished_("Ruby", finished_block)

Notice

If you run the example on a simulator on Apple silicon(M1),You need try to add arm64 to the Build Settings -> Architectures -> Excluded Architectures for Any iOS Simulator SDK.

Author

ping.cao

License

iMRuby is available under the MIT license. See the LICENSE file for more info.

tailang/iMRuby