Merge pull request #3 from greghe/feature-bitmap-array-constructors

Adds two constructors to ParticleSystem that accept an array of bitmaps.
Corresponds to Leonids pull request plattysoft#70.

LeonidsLib/src/main/java/com/plattysoft/leonids/ParticleSystem.java

@@ -218,6 +218,37 @@ public ParticleSystem(Activity a, int maxParticles, Bitmap bitmap, long timeToLi
 		}
 	}
 
+	/**
+	 * Utility constructor that receives an array of Bitmaps
+	 *
+	 * @param a The parent activity
+	 * @param maxParticles The maximum number of particles
+	 * @param bitmaps An array of bitmaps which will be randomly assigned to particles
+	 * @param timeToLive The time to live for the particles
+	 * @param parentViewId The view Id for the parent of the particle system
+	 */
+	public ParticleSystem(Activity a, int maxParticles, Bitmap[] bitmaps, long timeToLive, int parentViewId) {
+		this((ViewGroup) a.findViewById(parentViewId), maxParticles, timeToLive);
+		for (int i=0; i<mMaxParticles; i++) {
+			mParticles.add (new Particle (bitmaps[mRandom.nextInt(bitmaps.length)]));
+		}
+	}
+
+	/**
+	 * Utility constructor that receives an array of Bitmaps
+	 *
+	 * @param parentView The parent view group
+	 * @param maxParticles The maximum number of particles
+	 * @param bitmaps An array of bitmaps which will be randomly assigned to particles
+	 * @param timeToLive The time to live for the particles
+	 */
+	public ParticleSystem(ViewGroup parentView, int maxParticles, Bitmap[] bitmaps, long timeToLive) {
+		this(parentView, maxParticles, timeToLive);
+		for (int i=0; i<mMaxParticles; i++) {
+			mParticles.add (new Particle (bitmaps[mRandom.nextInt(bitmaps.length)]));
+		}
+	}
+
     /**
      * Utility constructor that receives an AnimationDrawable
      *