I have a C code which embeds Lua interpreter and some scripts. These scripts relies on stdin/stdout for user input/output.
I am trying to write a simple cocoa application with single NSTextField which will act as a stdin/stdout for my C code.
I was able to bind stdout as explained on this link:
What is the best way to redirect stdout to NSTextView in Cocoa?
How do I bind stdin with my NSTextField?
( In simple word, "scanf" should be able to receive input from text field. )
NOTE: I don't want to use NSTask. My C code has to be part of my cocoa app. ( basically there is no sub-process )
Related
Is there any way to convert the following applescript to Objective-C/C?
tell application "System Events" to set visible of process "Safari" to false
I know I could execute this applescript in Objective-C using the NSAppleScript class or calling system("osascript -e '...'"), however isn't there another way?
How does applescript do this?
Alternatively can I hide a window from another application from Objective-C/C?
Update:
I have found out that you can use SBApplication class to do this:
SBApplication *SystemEvents = [SBApplication applicationWithBundleIdentifier:#"com.apple.systemevents"];
/*SystemEventsApplicationProcess*/ id Safari = [[SystemEvents performSelector:#selector(applicationProcesses)] objectWithName:#"Safari"];
[Safari setVisible:NO]; // Doesn't work!
However this doesn't work as setVisible probably doesn't do what I think.
This is the class hierarchy of SystemEventsApplicationProcess:
SystemEventsApplicationProcess : SystemEventsProcess : SystemEventsUIElement : SystemEventsItem : SBObject : NSObject
And here are the methods available for these SystemEventsXXX classes:
SystemEventsApplicationProcess
applicationFile
SystemEventsProcess
setVisible:
visible
unixId
totalPartitionSize
shortName
partitionSpaceUsed
name
id
hasScriptingTerminology
setFrontmost:
frontmost
fileType
file
displayedName
creatorType
Classic
bundleIdentifier
backgroundOnly
architecture
acceptsRemoteEvents
acceptsHighLevelEvents
windows
menuBars
SystemEventsUIElement
select
clickAt:
setValue:
value
title
subrole
setSize:
size
setSelected:
selected
roleDescription
role
setPosition:
position
orientation
name
minimumValue
maximumValue
help
setFocused:
focused
entireContents
enabled
objectDescription
objectClass
accessibilityDescription
windows
valueIndicators
UIElements
toolBars
textFields
textAreas
tables
tabGroups
staticTexts
splitterGroups
splitters
sliders
sheets
scrollBars
scrollAreas
rows
relevanceIndicators
radioGroups
radioButtons
progressIndicators
popUpButtons
popOvers
outlines
menuItems
menuButtons
menuBarItems
menuBars
menus
lists
incrementors
images
growAreas
groups
drawers
comboBoxes
columns
colorWells
checkboxes
buttons
busyIndicators
browsers
attributes
actions
SystemEventsItem
setName:
name
id
removeActionFromUsingActionName:usingActionNumber:
pick
keyUp
keyDown
increment
editActionOfUsingActionName:usingActionNumber:
doScript
doFolderActionFolderActionCode:withItemList:withWindowSize:
decrement
confirm
cancel
attachedScripts
attachActionToUsing:
stop
start
saveAs:in:
moveTo:
exists
duplicateTo:withProperties:
delete
closeSaving:savingIn:
setProperties:
properties
objectClass
SBObject
// ...
NSObject
// ...
You can use NSRunningApplication, which represents (as its name implies) a running application, and has a -hide method.
NSWorkspace will give you a list of all the running apps: [[NSWorkspace sharedWorkspace] runningApplications], which you can filter, or you can get the object representing Safari using its bundle identifier: +[NSRunningApplication runningApplicationsWithBundleIdentifier:] (note that actually returns an array in case there are multiple running instances of the same app).
The code won't work unless you add the scripting bridge framework to your project and a couple other things. Have you done that... I can't tell. This link seems to have a good explanation of what is required if you need instructions.
By the way, "set visible" means hide the application just like if you hid it from the application menu. However if you want to hide an application I'm sure there's an NSWorkspace method.
Last bit of advice... for only a few lines of applescript code NSApplescript would be your best option. If you intend to use lots of applescript script code then the scripting bridge is the better choice, although I myself often just put a compiled script in my project and then use NSApplescript to initiate the handlers from that script. You can also use the ApplescriptObjC language too. You have lots of choices.
In a .xib for an application I'm working on, I have a quartz composer viewer object (QCView) in the window. I also have a patch controller (QCPatchController). The patch controller has its own class files in xCode, but they aren't doing anything right now. Following the apple docs, I was able to bind some values within the .nib file so if I edited a text field, it would pass this value to a published input on the QC document. Unfortunately, these docs say nothing about how to pass values programatically. How can I pass values (in code) to a QC patch?
Thanks in advance!
You should be able to use -setValue:forKeyPath:. For example:
[patchController setValue:#"foo" forKeyPath:#"patch.stringinput.value"];
I have an AppleScript that I am trying to convert to ScriptingBridge. Since my application is a C++/Obj-C application, ScriptingBridge is much easier to use and quite a bit faster (not to mention I hate dynamically building AppleScripts).
The AppleScript sends a message to Photoshop to open a file. The file parameter is sent as an alias, but ScriptingBridge imports the parameter as an id. I don't know what Obj-C object I should pass in?
I've tried passing an NSURL and an NSString (probably incorrectly :-P), but to no avail. Any suggestions on what I should be passing for the file alias?
The short answer is that you can't open documents in Photoshop with Scripting Bridge.
Apple's docs really spell it out like it is. All classes must have a container, which is a mutable array, that they need to be added to before they can be acted upon, as shown in the generated header...
#interface photoshopCS4Application : SBApplication
- (SBElementArray *) documents;
- (SBElementArray *) fonts;
- (SBElementArray *) notifiers;
... and that is the complete list of top-level containers available to us. The open command requires a photoshopCS4OpenOptions to be generated and populated. Because the API doesn't expose the array to store the newly created photoshopCS4OpenOptions object, we can't use a newly created photoshopCS4OpenOptions object. Therefore we can't make a target document and by extensions can't use the open command in Scripting Bridge. The same can be said of all the commands that require some kind of options object.
The only workaround that I have sorted out is to either open a document with native Applescript called from Cocoa or objc-appscript, and then parse the documents array looking for the one just opened. It's not ideal, but then neither is Scripting Bridge because it requires application developers write their scripting APIs in a very specific way that is not native to the OSA framework.
If your program is such that opening a Photoshop document can be executed outside your AppleScript script/Scripting Bridge code, Cocoa provides a method to open files with a specific application:
[[NSWorkspace sharedWorkspace] openFile:#"/Users/bavarious/Desktop/test.psd" withApplication:#"Adobe Photoshop CS4"];
or, if you want to use the default application that handles that file type, you can drop the application name altogether:
[[NSWorkspace sharedWorkspace] openFile:#"/Users/bavarious/Desktop/test.psd"];
Consider Appscript. http://appscript.sourceforge.net/
Here's the code using that:
APApplication *adobePhotoshopCs4 = [APApplication applicationWithName: #"Adobe Photoshop CS4"];
id result = [[adobePhotoshopCs4 open_] send];
(Note, I'm not a Cocoa programmer - I mainly use Appscript with Python but Appscript comes with ASTranslate which translates Applescript into Python, Ruby or Obj-C and that's the output - but I've found there are subtle mistakes in the past sometimes with the translator)
I am creating an app which needs to be opened if a user double clicks on a file with a certain extension.. How do i register the file extension with my app? and then read the contents?.
E.G the file could have the extension words.ThisApp and it could be in XML Format.. how could I read that in objective c into an array?
I think you should read the Document-Based Applications Overview.
To register an extension to your application, bring up the Target info window (Project » Edit Current Target "My Target"... at the bottom) and open the "Properties" tab. Fill in the blanks for your document type there. For more info, read Storing document type informations in the Application's Property List, contained inside the above guide.
To read XML data, consider using a NSXMLParser (google it for examples) to drive the results into a NSMutableArray as you see fit; and to get the data into your application, consider using a NSDocument subclass, as suggested (again) in the document-based application overview.
As you might understand, this document is quite a vital read.
I'm curious, what role does the int main function play in a Cocoa program? Virtually all of the sample code I've been looking at has only the following code in main.m:
#import <Cocoa/Cocoa.h>
int main(int argc, char *argv[])
{
return NSApplicationMain(argc, (const char **) argv);
}
What exactly is this doing, and where does the program actually start stepping through commands? It seems my conceptions need readjustment.
Since a Cocoa project starts like any other, the entry point for the Operating system is main. However the Cocoa Architecture is constructed to actually start the processing of your program from NSApplicationMain, which is responsible for loading the initial window from your application and starting up the Events loop used to process GUI events.
Apple has a very in depth discussion on this under the Cocoa Fundamentals Guide : The Core Application Architecture on Mac OS X
If you want to learn how control passes from "launch this" to the main() function, the execve man page has the details. You would also want to read about dyld. main() is a part of the Unix standard. Every single program that you can run effectively has a main().
As others have mentioned, NSApplicationMain passes control to Cocoa. The documentation is quite specific as to what it does.
One interesting note, NSApplicationMain doesn't actually every return. That is, if you were to separate the call to NSApplicationMain from the return in your main function and put code in between, that code would never be executed.
main() is the entry point for your program.
When you run your program that is the first function called. Your program ends when you exit that function.
Also note that this does not come from Objective-C. This is simple C.
Have a look at
Wikipedia's page on it
Value returned from main is returned by the process to operating system when the process is done.
Shell stores the value returned by last process and you can get it back with $? :
> ls
a b c
> echo $?
0
> ls x
x: No such file or directory
> echo $?
1
ls is an application like anything else.
You can use the return value to chain multiple processes together using shell script or anything else that can execute a process and check for return value.
I'm wondering where the code begins
executing (like why does an NSView
subclass execute and draw without me
explicitly calling it?) and if I'm not
supposed to stick my main loop in int
main() where does it go?
In an xcode project you have a main.m file that contains the 'int main' function. You won't actually find the code that calls the NSView draw explicitly, this code is hidden deep within an iPhone or Mac OS X framework. Just know that there is an event loop hidden deep within your 'int main' that checks for changes so that it knows when to update your view. You don't need to know where this event loop is, it's not useful information since you can override methods or create and assign delegates that can do things when this happens.
To get a better answer, you'll need to explain what you mean by a 'main loop' that you wanted to put inside the 'int main' function.
It's just weird to me coming off a
little experience in C++. It looks
unnatural that the main function would
be so empty.
You can encapsulate a billion lines of code into one function and put it into 'int main'. Don't be deceived by a main only having a few lines, that is done on purpose. Good programming teaches us to keep code in specific containers so that it is well organized. Apple chose to make the "real" launch point of their iPhone apps in this single line of code inside the main.m file:
int retVal = UIApplicationMain(argc, argv, nil, #"SillyAppDelegate");
From that one piece of code, an app's delegate is launched and won't return control to the main function until it is done.