cosmetic changes for JavaDoc and logging for scroll

Change-Id: I5bf1044c51b642d682d4a0b3b4dc18aabe3a12cd

3 files changed, 15 insertions, 4 deletions

diff --git a/src/com/google/android/droiddriver/UiDevice.java b/src/com/google/android/droiddriver/UiDevice.java
index 682409e..d55689a 100644
--- a/src/com/google/android/droiddriver/UiDevice.java
+++ b/src/com/google/android/droiddriver/UiDevice.java
@@ -45,6 +45,11 @@ public interface UiDevice {
 
   /**
    * Takes a screenshot of current window and stores it in {@code path} as PNG.
+   * <p>
+   * If this is used in a test which extends
+   * {@link android.test.ActivityInstrumentationTestCase2}, call this before
+   * {@code tearDown()} because {@code tearDown()} finishes activities created
+   * by {@link android.test.ActivityInstrumentationTestCase2#getActivity()}.
    *
    * @param path the path of file to save screenshot
    * @return true if screen shot is created successfully
diff --git a/src/com/google/android/droiddriver/scroll/DynamicSentinelStrategy.java b/src/com/google/android/droiddriver/scroll/DynamicSentinelStrategy.java
index 7970e26..488b231 100644
--- a/src/com/google/android/droiddriver/scroll/DynamicSentinelStrategy.java
+++ b/src/com/google/android/droiddriver/scroll/DynamicSentinelStrategy.java
@@ -97,11 +97,14 @@ public class DynamicSentinelStrategy extends AbstractSentinelStrategy {
       }
 
       String newString = getUniqueStringFromSentinel(newSentinel);
-      // If newString is null, newSentinel must be partially shown. In this case
-      // we return true to allow further scrolling. But program error could also
-      // cause this, e.g. a bad choice of GetStrategy. log for debugging.
+      // A legitimate case for newString being null is when newSentinel is
+      // partially shown. We return true to allow further scrolling. But program
+      // error could also cause this, e.g. a bad choice of GetStrategy, which
+      // results in unnecessary scroll actions that have no visual effect. This
+      // log helps troubleshooting in the latter case.
       if (newString == null) {
-        Logs.logfmt(Log.WARN, "Unique String under sentinel %s is null", newSentinel);
+        Logs.logfmt(Log.WARN, "Unique String is null: sentinel=%s, uniqueStringFinder=%s",
+            newSentinel, uniqueStringFinder);
         return true;
       }
       if (newString.equals(getUniqueStringFromSentinel(oldSentinel))) {
diff --git a/src/com/google/android/droiddriver/uiautomation/UiAutomationDriver.java b/src/com/google/android/droiddriver/uiautomation/UiAutomationDriver.java
index f9c7578..49b04ac 100644
--- a/src/com/google/android/droiddriver/uiautomation/UiAutomationDriver.java
+++ b/src/com/google/android/droiddriver/uiautomation/UiAutomationDriver.java
@@ -26,6 +26,7 @@ import android.view.accessibility.AccessibilityNodeInfo;
 
 import com.google.android.droiddriver.base.BaseDroidDriver;
 import com.google.android.droiddriver.exceptions.TimeoutException;
+import com.google.android.droiddriver.util.Logs;
 import com.google.common.primitives.Longs;
 
 /**
@@ -89,6 +90,7 @@ public class UiAutomationDriver extends BaseDroidDriver {
    * clear the AccessibilityNodeInfoCache.
    */
   public void clearAccessibilityNodeInfoCache() {
+    Logs.call(this, "clearAccessibilityNodeInfoCache");
     uiDevice.sleep();
     uiDevice.wakeUp();
   }
@@ -100,6 +102,7 @@ public class UiAutomationDriver extends BaseDroidDriver {
    * discretion.
    */
   public void clearAccessibilityNodeInfoCacheHack() {
+    Logs.call(this, "clearAccessibilityNodeInfoCacheHack");
     AccessibilityManager accessibilityManager =
         (AccessibilityManager) context.getInstrumentation().getTargetContext()
             .getSystemService(Context.ACCESSIBILITY_SERVICE);