| java.lang.Object | |
| ↳ | android.os.Looper |
Class used to run a message loop for a thread. Threads by default do
not have a message loop associated with them; to create one, call
prepare() in the thread that is to run the loop, and then
loop() to have it process messages until the loop is stopped.
Most interaction with a message loop is through the
Handler class.
This is a typical example of the implementation of a Looper thread,
using the separation of prepare() and loop() to create an
initial Handler to communicate with the Looper.
class LooperThread extends Thread {
public Handler mHandler;
public void run() {
Looper.prepare();
mHandler = new Handler() {
public void handleMessage(Message msg) {
// process incoming messages here
}
};
Looper.loop();
}
}
| Public Methods | |||||||||||
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Returns the application's main looper, which lives in the main thread of the application.
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Return the Thread associated with this Looper.
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Run the message queue in this thread.
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Return the Looper object associated with the current thread.
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Return the
MessageQueue object associated with the current
thread. | |||||||||||
Initialize the current thread as a looper.
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Initialize the current thread as a looper, marking it as an
application's main looper.
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Quits the looper.
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Quits the looper safely.
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Control logging of messages as they are processed by this Looper.
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Returns a string containing a concise, human-readable description of this
object.
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[Expand]
Inherited Methods | |||||||||||
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From class
java.lang.Object
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Returns the application's main looper, which lives in the main thread of the application.
Run the message queue in this thread. Be sure to call
quit() to end the loop.
Return the Looper object associated with the current thread. Returns null if the calling thread is not associated with a Looper.
Return the MessageQueue object associated with the current
thread. This must be called from a thread running a Looper, or a
NullPointerException will be thrown.
Initialize the current thread as a looper, marking it as an
application's main looper. The main looper for your application
is created by the Android environment, so you should never need
to call this function yourself. See also: prepare()
Quits the looper.
Causes the loop() method to terminate without processing any
more messages in the message queue.
Any attempt to post messages to the queue after the looper is asked to quit will fail.
For example, the sendMessage(Message) method will return false.
Using this method may be unsafe because some messages may not be delivered
before the looper terminates. Consider using quitSafely() instead to ensure
that all pending work is completed in an orderly manner.
Quits the looper safely.
Causes the loop() method to terminate as soon as all remaining messages
in the message queue that are already due to be delivered have been handled.
However pending delayed messages with due times in the future will not be
delivered before the loop terminates.
Any attempt to post messages to the queue after the looper is asked to quit will fail.
For example, the sendMessage(Message) method will return false.
Control logging of messages as they are processed by this Looper. If enabled, a log message will be written to printer at the beginning and ending of each message dispatch, identifying the target Handler and message contents.
| printer | A Printer object that will receive log messages, or null to disable message logging. |
|---|
Returns a string containing a concise, human-readable description of this object. Subclasses are encouraged to override this method and provide an implementation that takes into account the object's type and data. The default implementation is equivalent to the following expression:
getClass().getName() + '@' + Integer.toHexString(hashCode())
See Writing a useful
toString method
if you intend implementing your own toString method.