From 716bbc7b787cd16978fea7d9370b430ce2cb26f8 Mon Sep 17 00:00:00 2001
From: cpfeiffer <cpfeiffer@users.noreply.github.com>
Date: Sat, 25 Jul 2015 00:08:15 +0200
Subject: [PATCH] Avoid NPE when fetching activity data:

java.lang.NullPointerException: Attempt to write to field 'int nodomain.freeyourgadget.gadgetbridge.miband.MiBandSupport$ActivityStruct.activityDataHolderProgress' on a null object reference
        at nodomain.freeyourgadget.gadgetbridge.miband.MiBandSupport.flushActivityDataHolder(MiBandSupport.java:748)
        at nodomain.freeyourgadget.gadgetbridge.miband.MiBandSupport.handleActivityNotif(MiBandSupport.java:689)
        at nodomain.freeyourgadget.gadgetbridge.miband.MiBandSupport.onCharacteristicChanged(MiBandSupport.java:583)
        at nodomain.freeyourgadget.gadgetbridge.btle.BtLEQueue$2.onCharacteristicChanged(BtLEQueue.java:369)
---
 .../gadgetbridge/miband/MiBandSupport.java            | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/miband/MiBandSupport.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/miband/MiBandSupport.java
index 33da795d0..6d2b49fa0 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/miband/MiBandSupport.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/miband/MiBandSupport.java
@@ -672,7 +672,6 @@ public class MiBandSupport extends AbstractBTLEDeviceSupport {
 
         if (activityStruct.activityDataRemainingBytes == 0) {
             sendAckDataTransfer(activityStruct.activityDataTimestampToAck, activityStruct.activityDataUntilNextHeader);
-            flushActivityDataHolder();
         }
     }
 
@@ -712,6 +711,11 @@ public class MiBandSupport extends AbstractBTLEDeviceSupport {
     }
 
     private void flushActivityDataHolder() {
+        if (activityStruct == null) {
+            LOG.debug("nothing to flush, struct is already null");
+            return;
+        }
+        LOG.debug("flushing activity data holder");
         byte category, intensity, steps;
 
         ActivityDatabaseHandler dbHandler = GBApplication.getActivityDatabaseHandler();
@@ -770,6 +774,10 @@ public class MiBandSupport extends AbstractBTLEDeviceSupport {
             TransactionBuilder builder = performInitialized("send acknowledge");
             builder.write(getCharacteristic(MiBandService.UUID_CHARACTERISTIC_CONTROL_POINT), ack);
             builder.queue(getQueue());
+
+            // flush to the DB after sending the ACK
+            flushActivityDataHolder();
+
             //The last data chunk sent by the miband has always length 0.
             //When we ack this chunk, the transfer is done.
             if(getDevice().isBusy() && bytesTransferred==0) {
@@ -781,6 +789,7 @@ public class MiBandSupport extends AbstractBTLEDeviceSupport {
     }
 
     private void handleActivityFetchFinish() {
+        LOG.info("Fetching activity data has finished.");
         activityStruct = null;
         unsetBusy();
     }