Missed signal in FusedPrintersLoader.

1. In the FusedPrintersLoader we start observing the printers on
   the device and if they change we send the result. If however,
   the printers are already loaded in our session (because it
   joined an ongoing printer discovery) and the pritners do not
   change, the loader never sends its result. Now we are registring
   the callback only after historical printers are loaded. We
   also immediately check after starting discovery whether the
   there are printers in the discovery session and if so deliver
   them.

2. Improved logging in the FusedPrintersLoader.

bug:10940712

Change-Id: Ieb9b897d64780742125b29309462dea3eda170a6

1 files changed, 40 insertions, 21 deletions

diff --git a/packages/PrintSpooler/src/com/android/printspooler/FusedPrintersProvider.java b/packages/PrintSpooler/src/com/android/printspooler/FusedPrintersProvider.java
index b4eb08a566d2..3a1a3c40662c 100644
--- a/packages/PrintSpooler/src/com/android/printspooler/FusedPrintersProvider.java
+++ b/packages/PrintSpooler/src/com/android/printspooler/FusedPrintersProvider.java
@@ -128,7 +128,7 @@ public class FusedPrintersProvider extends Loader<List<PrinterInfo>> {
     @Override
     protected void onStartLoading() {
         if (DEBUG) {
-            Log.i(LOG_TAG, "onStartLoading()" + FusedPrintersProvider.this.hashCode());
+            Log.i(LOG_TAG, "onStartLoading() " + FusedPrintersProvider.this.hashCode());
         }
         // The contract is that if we already have a valid,
         // result the we have to deliver it immediately.
@@ -143,7 +143,7 @@ public class FusedPrintersProvider extends Loader<List<PrinterInfo>> {
     @Override
     protected void onStopLoading() {
         if (DEBUG) {
-            Log.i(LOG_TAG, "onStopLoading()" + FusedPrintersProvider.this.hashCode());
+            Log.i(LOG_TAG, "onStopLoading() " + FusedPrintersProvider.this.hashCode());
         }
         onCancelLoad();
     }
@@ -151,7 +151,7 @@ public class FusedPrintersProvider extends Loader<List<PrinterInfo>> {
     @Override
     protected void onForceLoad() {
         if (DEBUG) {
-            Log.i(LOG_TAG, "onForceLoad()" + FusedPrintersProvider.this.hashCode());
+            Log.i(LOG_TAG, "onForceLoad() " + FusedPrintersProvider.this.hashCode());
         }
         loadInternal();
     }
@@ -161,37 +161,52 @@ public class FusedPrintersProvider extends Loader<List<PrinterInfo>> {
             PrintManager printManager = (PrintManager) getContext()
                     .getSystemService(Context.PRINT_SERVICE);
             mDiscoverySession = printManager.createPrinterDiscoverySession();
+            mPersistenceManager.readPrinterHistory();
+        }
+        if (mPersistenceManager.isReadHistoryCompleted()
+                && !mDiscoverySession.isPrinterDiscoveryStarted()) {
             mDiscoverySession.setOnPrintersChangeListener(new OnPrintersChangeListener() {
                 @Override
                 public void onPrintersChanged() {
-                    ArrayMap<PrinterId, PrinterInfo> printersMap =
-                            new ArrayMap<PrinterId, PrinterInfo>();
-                    List<PrinterInfo> printers = mDiscoverySession.getPrinters();
-                    final int printerCount = printers.size();
-                    for (int i = 0; i < printerCount; i++) {
-                        PrinterInfo printer = printers.get(i);
-                        printersMap.put(printer.getId(), printer);
+                    if (DEBUG) {
+                        Log.i(LOG_TAG, "onPrintersChanged() count:"
+                                + mDiscoverySession.getPrinters().size()
+                                + " " + FusedPrintersProvider.this.hashCode());
                     }
-                    computeAndDeliverResult(printersMap);
+                    updatePrinters(mDiscoverySession.getPrinters());
                 }
             });
-            mPersistenceManager.readPrinterHistory();
-        }
-        if (mPersistenceManager.isReadHistoryCompleted()
-                && !mDiscoverySession.isPrinterDiscoveryStarted()) {
             final int favoriteCount = mFavoritePrinters.size();
             List<PrinterId> printerIds = new ArrayList<PrinterId>(favoriteCount);
             for (int i = 0; i < favoriteCount; i++) {
                 printerIds.add(mFavoritePrinters.get(i).getId());
             }
             mDiscoverySession.startPrinterDisovery(printerIds);
+            List<PrinterInfo> printers = mDiscoverySession.getPrinters();
+            if (!printers.isEmpty()) {
+                updatePrinters(printers);
+            }
+        }
+    }
+
+    private void updatePrinters(List<PrinterInfo> printers) {
+        if (mPrinters.equals(printers)) {
+            return;
+        }
+        ArrayMap<PrinterId, PrinterInfo> printersMap =
+                new ArrayMap<PrinterId, PrinterInfo>();
+        final int printerCount = printers.size();
+        for (int i = 0; i < printerCount; i++) {
+            PrinterInfo printer = printers.get(i);
+            printersMap.put(printer.getId(), printer);
         }
+        computeAndDeliverResult(printersMap);
     }
 
     @Override
     protected boolean onCancelLoad() {
         if (DEBUG) {
-            Log.i(LOG_TAG, "onCancelLoad()" + FusedPrintersProvider.this.hashCode());
+            Log.i(LOG_TAG, "onCancelLoad() " + FusedPrintersProvider.this.hashCode());
         }
         return cancelInternal();
     }
@@ -214,7 +229,7 @@ public class FusedPrintersProvider extends Loader<List<PrinterInfo>> {
     @Override
     protected void onReset() {
         if (DEBUG) {
-            Log.i(LOG_TAG, "onReset()" + FusedPrintersProvider.this.hashCode());
+            Log.i(LOG_TAG, "onReset() " + FusedPrintersProvider.this.hashCode());
         }
         onStopLoading();
         mPrinters.clear();
@@ -227,7 +242,7 @@ public class FusedPrintersProvider extends Loader<List<PrinterInfo>> {
     @Override
     protected void onAbandon() {
         if (DEBUG) {
-            Log.i(LOG_TAG, "onAbandon()" + FusedPrintersProvider.this.hashCode());
+            Log.i(LOG_TAG, "onAbandon() " + FusedPrintersProvider.this.hashCode());
         }
         onStopLoading();
     }
@@ -288,7 +303,8 @@ public class FusedPrintersProvider extends Loader<List<PrinterInfo>> {
 
         public void readPrinterHistory() {
             if (DEBUG) {
-                Log.i(LOG_TAG, "read history started");
+                Log.i(LOG_TAG, "read history started "
+                        + FusedPrintersProvider.this.hashCode());
             }
             mReadHistoryInProgress = true;
             mReadTask = new ReadTask();
@@ -364,7 +380,7 @@ public class FusedPrintersProvider extends Loader<List<PrinterInfo>> {
             @Override
             protected void onPostExecute(List<PrinterInfo> printers) {
                 if (DEBUG) {
-                    Log.i(LOG_TAG, "read history completed"
+                    Log.i(LOG_TAG, "read history completed "
                             + FusedPrintersProvider.this.hashCode());
                 }
 
@@ -393,7 +409,10 @@ public class FusedPrintersProvider extends Loader<List<PrinterInfo>> {
                 try {
                     in = mStatePersistFile.openRead();
                 } catch (FileNotFoundException fnfe) {
-                    Log.i(LOG_TAG, "No existing printer history.");
+                    if (DEBUG) {
+                        Log.i(LOG_TAG, "No existing printer history "
+                                + FusedPrintersProvider.this.hashCode());
+                    }
                     return new ArrayList<PrinterInfo>();
                 }
                 try {