NSRunLoop

Inherits From: NSObject

Conforms To: NSObject (NSObject)

Declared In: Foundation/NSRunLoop.h

Class Description

The NSRunLoop class declares the programmatic interface to objects that manage input sources. An NSRunLoop object processes input for sources such as mouse and keyboard events from the window system, NSTimers, POSIX file descriptors, and NSConnections, based on a mode argument. A given NSRunLoop object processes input for input sources associated with a particular mode.

In general, your application won't need to either create or explicitly manage NSRunLoop objects. Each thread has an NSRunLoop object automatically created for it. The NSApplication object creates a default thread and therefore creates a default run loop.

Applications wanting to perform their own explicit run loop management should send the currentRunLoop message to the NSRunLoop class object to obtain the NSRunLoop object for the current thread, then invoke one of the methods described below in Running a Run Loop to obtain input.

Currently defined modes are:

NSDefaultRunLoopMode Use this mode to deal with input sources other than NSConnections. Defined in the Foundation/NSRunLoop.h header file.

NSConnectionReplyMode Use this mode to indicate NSConnections waiting for replies. Defined in the Foundation/NSConnection.h header file.

Accessing the Current Run Loop

• + (NSRunLoop *)currentRunLoop Returns the NSRunLoop for the current thread.
• - (NSString *)currentMode Returns the current run loop mode.
• - (NSDate *)limitDateForMode:(NSString *)mode Polls timers and platform-specific input managers for their limit date (if any). Timers will fire if appropriate. Returns nil if there are no input sources for this mode.

• - (void)addTimer:(NSTimer *)aTimer Registers the timer aTimer with input filter mode. The run forMode:(NSString *)mode loop causes the timer to fire at its scheduled fire date. Note that timers are removed from modes if they supply nil as their fire date.

• - (void)acceptInputForMode:(NSString *)mode Runs the run loop, accepting input from the input sources beforeDate:(NSDate *)limitDate for the mode specified by mode until the time specified by limitDate.
• - (void)run Runs the run loop in the default mode until there is nothing to do.
• - (BOOL)runMode:(NSString *)mode Runs the run loop, accepting input from filter mode beforeDate:(NSDate *)limitDate until limitDate or until the earliest limit date for input sources in this mode. Returns NO without starting the run loop if there are no limit dates set for input sources (that is, there's nothing to do).
• - (void)runUntilDate:(NSDate *)limitDate Runs the run loop until limitDate or until there are no limit dates set for input sources (that is, there's nothing to do).