diff options
Diffstat (limited to 'core/java/android/database/ContentObserver.java')
-rw-r--r-- | core/java/android/database/ContentObserver.java | 79 |
1 files changed, 70 insertions, 9 deletions
diff --git a/core/java/android/database/ContentObserver.java b/core/java/android/database/ContentObserver.java index 4c20262..e4fbc28 100644 --- a/core/java/android/database/ContentObserver.java +++ b/core/java/android/database/ContentObserver.java @@ -16,6 +16,7 @@ package android.database; +import android.net.Uri; import android.os.Handler; /** @@ -83,6 +84,9 @@ public abstract class ContentObserver { /** * This method is called when a content change occurs. + * <p> + * Subclasses should override this method to handle content changes. + * </p> * * @param selfChange True if this is a self-change notification. */ @@ -91,32 +95,89 @@ public abstract class ContentObserver { } /** - * Dispatches a change notification to the observer. + * This method is called when a content change occurs. + * Includes the changed content Uri when available. + * <p> + * Subclasses should override this method to handle content changes. + * To ensure correct operation on older versions of the framework that + * did not provide a Uri argument, applications should also implement + * the {@link #onChange(boolean)} overload of this method whenever they + * implement the {@link #onChange(boolean, Uri)} overload. + * </p><p> + * Example implementation: + * <pre><code> + * // Implement the onChange(boolean) method to delegate the change notification to + * // the onChange(boolean, Uri) method to ensure correct operation on older versions + * // of the framework that did not have the onChange(boolean, Uri) method. + * {@literal @Override} + * public void onChange(boolean selfChange) { + * onChange(selfChange, null); + * } + * + * // Implement the onChange(boolean, Uri) method to take advantage of the new Uri argument. + * {@literal @Override} + * public void onChange(boolean selfChange, Uri uri) { + * // Handle change. + * } + * </code></pre> + * </p> * + * @param selfChange True if this is a self-change notification. + * @param uri The Uri of the changed content, or null if unknown. + */ + public void onChange(boolean selfChange, Uri uri) { + onChange(selfChange); + } + + /** + * Dispatches a change notification to the observer. + * <p> * If a {@link Handler} was supplied to the {@link ContentObserver} constructor, * then a call to the {@link #onChange} method is posted to the handler's message queue. * Otherwise, the {@link #onChange} method is invoked immediately on this thread. + * </p> * * @param selfChange True if this is a self-change notification. + * + * @deprecated Use {@link #dispatchChange(boolean, Uri)} instead. */ + @Deprecated public final void dispatchChange(boolean selfChange) { + dispatchChange(selfChange, null); + } + + /** + * Dispatches a change notification to the observer. + * Includes the changed content Uri when available. + * <p> + * If a {@link Handler} was supplied to the {@link ContentObserver} constructor, + * then a call to the {@link #onChange} method is posted to the handler's message queue. + * Otherwise, the {@link #onChange} method is invoked immediately on this thread. + * </p> + * + * @param selfChange True if this is a self-change notification. + * @param uri The Uri of the changed content, or null if unknown. + */ + public final void dispatchChange(boolean selfChange, Uri uri) { if (mHandler == null) { - onChange(selfChange); + onChange(selfChange, uri); } else { - mHandler.post(new NotificationRunnable(selfChange)); + mHandler.post(new NotificationRunnable(selfChange, uri)); } } private final class NotificationRunnable implements Runnable { - private final boolean mSelf; + private final boolean mSelfChange; + private final Uri mUri; - public NotificationRunnable(boolean self) { - mSelf = self; + public NotificationRunnable(boolean selfChange, Uri uri) { + mSelfChange = selfChange; + mUri = uri; } @Override public void run() { - ContentObserver.this.onChange(mSelf); + ContentObserver.this.onChange(mSelfChange, mUri); } } @@ -128,10 +189,10 @@ public abstract class ContentObserver { } @Override - public void onChange(boolean selfChange) { + public void onChange(boolean selfChange, Uri uri) { ContentObserver contentObserver = mContentObserver; if (contentObserver != null) { - contentObserver.dispatchChange(selfChange); + contentObserver.dispatchChange(selfChange, uri); } } |