WindowId
  public
  
  
  
  class
  WindowId
  
    extends Object
  
  
  
  
  
      implements
      
        Parcelable
      
  
  
| java.lang.Object | |
| ↳ | android.view.WindowId | 
Safe identifier for a window.  This currently allows you to retrieve and observe
 the input focus state of the window.  Most applications will
 not use this, instead relying on the simpler (and more efficient) methods available
 on View.  This classes is useful when window input interactions need to be
 done across processes: the class itself is a Parcelable that can be passed to other
 processes for them to interact with your window, and it provides a limited safe API
 that doesn't allow the other process to negatively harm your window.
Summary
| Nested classes | |
|---|---|
| 
        
        
        
        
        class | WindowId.FocusObserverSubclass for observing changes to the focus state of an  | 
| Inherited constants | 
|---|
| Fields | |
|---|---|
| 
    public
    static
    final
    Creator<WindowId> | CREATOR
 | 
| Public methods | |
|---|---|
| 
        
        
        
        
        
        int | 
      describeContents()
      Describe the kinds of special objects contained in this Parcelable instance's marshaled representation. | 
| 
        
        
        
        
        
        boolean | 
      equals(Object otherObj)
      Comparison operator on two IntentSender objects, such that true is returned then they both represent the same operation from the same package. | 
| 
        
        
        
        
        
        int | 
      hashCode()
      Returns a hash code value for the object. | 
| 
        
        
        
        
        
        boolean | 
      isFocused()
      Retrieve the current focus state of the associated window. | 
| 
        
        
        
        
        
        void | 
      registerFocusObserver(WindowId.FocusObserver observer)
      Start monitoring for changes in the focus state of the window. | 
| 
        
        
        
        
        
        String | 
      toString()
      Returns a string representation of the object. | 
| 
        
        
        
        
        
        void | 
      unregisterFocusObserver(WindowId.FocusObserver observer)
      Stop monitoring changes in the focus state of the window. | 
| 
        
        
        
        
        
        void | 
      writeToParcel(Parcel out, int flags)
      Flatten this object in to a Parcel. | 
| Inherited methods | |
|---|---|
Fields
Public methods
describeContents
public int describeContents ()
Describe the kinds of special objects contained in this Parcelable
 instance's marshaled representation. For example, if the object will
 include a file descriptor in the output of writeToParcel(android.os.Parcel, int),
 the return value of this method must include the
 CONTENTS_FILE_DESCRIPTOR bit.
| Returns | |
|---|---|
| int | a bitmask indicating the set of special object types marshaled
 by this Parcelable object instance.
 Value is either 0orCONTENTS_FILE_DESCRIPTOR | 
equals
public boolean equals (Object otherObj)
Comparison operator on two IntentSender objects, such that true is returned then they both represent the same operation from the same package.
| Parameters | |
|---|---|
| otherObj | Object: This value may benull. | 
| Returns | |
|---|---|
| boolean | trueif this object is the same as the obj
          argument;falseotherwise. | 
hashCode
public int hashCode ()
Returns a hash code value for the object. This method is
 supported for the benefit of hash tables such as those provided by
 HashMap.
 
 The general contract of hashCode is:
 
- Whenever it is invoked on the same object more than once during
     an execution of a Java application, the hashCodemethod must consistently return the same integer, provided no information used inequalscomparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
- If two objects are equal according to the equalsmethod, then calling thehashCodemethod on each of the two objects must produce the same integer result.
- It is not required that if two objects are unequal
     according to the equalsmethod, then calling thehashCodemethod on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.
| Returns | |
|---|---|
| int | a hash code value for this object. | 
isFocused
public boolean isFocused ()
Retrieve the current focus state of the associated window.
| Returns | |
|---|---|
| boolean | |
registerFocusObserver
public void registerFocusObserver (WindowId.FocusObserver observer)
Start monitoring for changes in the focus state of the window.
| Parameters | |
|---|---|
| observer | WindowId.FocusObserver | 
toString
public String toString ()
Returns a string representation of the object.
| Returns | |
|---|---|
| String | a string representation of the object. | 
unregisterFocusObserver
public void unregisterFocusObserver (WindowId.FocusObserver observer)
Stop monitoring changes in the focus state of the window.
| Parameters | |
|---|---|
| observer | WindowId.FocusObserver | 
writeToParcel
public void writeToParcel (Parcel out, int flags)
Flatten this object in to a Parcel.
| Parameters | |
|---|---|
| out | Parcel: The Parcel in which the object should be written.
 This value cannot benull. | 
| flags | int: Additional flags about how the object should be written.
 May be 0 orParcelable.PARCELABLE_WRITE_RETURN_VALUE.
 Value is either0or a combination ofParcelable.PARCELABLE_WRITE_RETURN_VALUE, and android.os.Parcelable.PARCELABLE_ELIDE_DUPLICATES | 
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Last updated 2025-02-10 UTC.
