handle some NPEs Android2D

Author: codeanticode

core/src/processing/core/PGraphicsAndroid2D.java

@@ -26,6 +26,7 @@
 import java.util.zip.GZIPInputStream;
 
 import processing.data.XML;
+import android.app.Activity;
 import android.app.ActivityManager;
 import android.app.ActivityManager.MemoryInfo;
 import android.graphics.*;
@@ -147,7 +148,7 @@ protected void allocate() {
 
   @Override
   public void dispose() {
-    bitmap.recycle();
+    if (bitmap != null) bitmap.recycle();
   }
 
 
@@ -1089,7 +1090,9 @@ protected void imageImpl(PImage src,
     // but I don't think it is particularly efficient, as the bitmaps are stored
     // in native heap for Android 10 and older.
     MemoryInfo mi = new MemoryInfo();
-    ActivityManager activityManager = (ActivityManager) parent.getActivity().getSystemService(android.content.Context.ACTIVITY_SERVICE);
+    Activity activity = parent.getActivity();
+    if (activity == null) return;
+    ActivityManager activityManager = (ActivityManager) activity.getSystemService(android.content.Context.ACTIVITY_SERVICE);
     activityManager.getMemoryInfo(mi);
     if (mi.lowMemory) {
       src.bitmap.recycle();