--- /dev/null
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.support.v2.content;
+
+import android.content.Context;
+import android.database.ContentObserver;
+import android.database.Cursor;
+import android.net.Uri;
+
+import java.io.FileDescriptor;
+import java.io.PrintWriter;
+import java.util.Arrays;
+
+/**
+ * Static library support version of the framework's {@link android.content.CursorLoader}.
+ * Used to write apps that run on platforms prior to Android 3.0. When running
+ * on Android 3.0 or above, this implementation is still used; it does not try
+ * to switch to the framework's implementation. See the framework SDK
+ * documentation for a class overview.
+ */
+public class CursorLoader extends AsyncTaskLoader<Cursor> {
+ final ForceLoadContentObserver mObserver;
+
+ Uri mUri;
+ String[] mProjection;
+ String mSelection;
+ String[] mSelectionArgs;
+ String mSortOrder;
+
+ Cursor mCursor;
+
+ /* Runs on a worker thread */
+ @Override
+ public Cursor loadInBackground() {
+ Cursor cursor = getContext().getContentResolver().query(mUri, mProjection, mSelection,
+ mSelectionArgs, mSortOrder);
+ if (cursor != null) {
+ // Ensure the cursor window is filled
+ cursor.getCount();
+ registerContentObserver(cursor, mObserver);
+ }
+ return cursor;
+ }
+
+ /**
+ * Registers an observer to get notifications from the content provider
+ * when the cursor needs to be refreshed.
+ */
+ void registerContentObserver(Cursor cursor, ContentObserver observer) {
+ cursor.registerContentObserver(mObserver);
+ }
+
+ /* Runs on the UI thread */
+ @Override
+ public void deliverResult(Cursor cursor) {
+ if (isReset()) {
+ // An async query came in while the loader is stopped
+ if (cursor != null) {
+ cursor.close();
+ }
+ return;
+ }
+ Cursor oldCursor = mCursor;
+ mCursor = cursor;
+
+ if (isStarted()) {
+ super.deliverResult(cursor);
+ }
+
+ if (oldCursor != null && oldCursor != cursor && !oldCursor.isClosed()) {
+ oldCursor.close();
+ }
+ }
+
+ /**
+ * Creates an empty unspecified CursorLoader. You must follow this with
+ * calls to {@link #setUri(Uri)}, {@link #setSelection(String)}, etc
+ * to specify the query to perform.
+ */
+ public CursorLoader(Context context) {
+ super(context);
+ mObserver = new ForceLoadContentObserver();
+ }
+
+ /**
+ * Creates a fully-specified CursorLoader. See
+ * {@link ContentResolver#query(Uri, String[], String, String[], String)
+ * ContentResolver.query()} for documentation on the meaning of the
+ * parameters. These will be passed as-is to that call.
+ */
+ public CursorLoader(Context context, Uri uri, String[] projection, String selection,
+ String[] selectionArgs, String sortOrder) {
+ super(context);
+ mObserver = new ForceLoadContentObserver();
+ mUri = uri;
+ mProjection = projection;
+ mSelection = selection;
+ mSelectionArgs = selectionArgs;
+ mSortOrder = sortOrder;
+ }
+
+ /**
+ * Starts an asynchronous load of the contacts list data. When the result is ready the callbacks
+ * will be called on the UI thread. If a previous load has been completed and is still valid
+ * the result may be passed to the callbacks immediately.
+ *
+ * Must be called from the UI thread
+ */
+ @Override
+ protected void onStartLoading() {
+ if (mCursor != null) {
+ deliverResult(mCursor);
+ }
+ if (takeContentChanged() || mCursor == null) {
+ forceLoad();
+ }
+ }
+
+ /**
+ * Must be called from the UI thread
+ */
+ @Override
+ protected void onStopLoading() {
+ // Attempt to cancel the current load task if possible.
+ cancelLoad();
+ }
+
+ @Override
+ public void onCanceled(Cursor cursor) {
+ if (cursor != null && !cursor.isClosed()) {
+ cursor.close();
+ }
+ }
+
+ @Override
+ protected void onReset() {
+ super.onReset();
+
+ // Ensure the loader is stopped
+ onStopLoading();
+
+ if (mCursor != null && !mCursor.isClosed()) {
+ mCursor.close();
+ }
+ mCursor = null;
+ }
+
+ public Uri getUri() {
+ return mUri;
+ }
+
+ public void setUri(Uri uri) {
+ mUri = uri;
+ }
+
+ public String[] getProjection() {
+ return mProjection;
+ }
+
+ public void setProjection(String[] projection) {
+ mProjection = projection;
+ }
+
+ public String getSelection() {
+ return mSelection;
+ }
+
+ public void setSelection(String selection) {
+ mSelection = selection;
+ }
+
+ public String[] getSelectionArgs() {
+ return mSelectionArgs;
+ }
+
+ public void setSelectionArgs(String[] selectionArgs) {
+ mSelectionArgs = selectionArgs;
+ }
+
+ public String getSortOrder() {
+ return mSortOrder;
+ }
+
+ public void setSortOrder(String sortOrder) {
+ mSortOrder = sortOrder;
+ }
+
+ @Override
+ public void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args) {
+ super.dump(prefix, fd, writer, args);
+ writer.print(prefix); writer.print("mUri="); writer.println(mUri);
+ writer.print(prefix); writer.print("mProjection=");
+ writer.println(Arrays.toString(mProjection));
+ writer.print(prefix); writer.print("mSelection="); writer.println(mSelection);
+ writer.print(prefix); writer.print("mSelectionArgs=");
+ writer.println(Arrays.toString(mSelectionArgs));
+ writer.print(prefix); writer.print("mSortOrder="); writer.println(mSortOrder);
+ writer.print(prefix); writer.print("mCursor="); writer.println(mCursor);
+ writer.print(prefix); writer.print("mContentChanged="); writer.println(mContentChanged);
+ }
+}
notaz.gp2x.de / android_pandora.git / blobdiff