added start pause restart methods in BallView

Author: glomadrian

app/src/main/res/layout/activity_main.xml

@@ -240,7 +240,7 @@
         android:layout_width="100dp"
         android:layout_height="100dp"
         lib:balls="10"
-        lib:movement_cycle_time="1500"
+        lib:movement_cycle_time="2500"
         lib:ball_colors="@array/colors"
         lib:path="diamond"
         lib:ball_size="4dp"

loadingballs/src/main/java/com/github/glomadrian/loadingballssample/BallView.java

@@ -25,6 +25,7 @@ public class BallView extends View {
   private float maxBallSize;
   private float ballSize = 20;
   private BallPathAnimator ballPathAnimator;
+  private BallSizeAnimator ballSizeAnimator;
   private int numberOfBalls = 3;
   private int ballSizeAnimationDuration = 400;
   private int ballPathAnimationDuration = 1500;
@@ -81,28 +82,24 @@ private void initColorsAttributes(TypedArray attributes) {
   @Override
   protected void onSizeChanged(int w, int h, int oldw, int oldh) {
     super.onSizeChanged(w, h, oldw, oldh);
-
     Path path = PathFactory.makePath(pathType, new Point(w / 2, h / 2), w, h, (int) maxBallSize);
-
     initBallPathAnimator(path);
-
     if (sizeAnimationEnabled) {
       initBallSizeAnimator(path);
     }
+    start();
   }
 
   private void initBallPathAnimator(Path path) {
     ballPathAnimator = new BallPathAnimator(path, ballPathAnimationDuration);
     ballPathAnimator.setBallPathAnimatorListener(new AnimatorListener());
     ballPathAnimator.addBalls(balls);
-    ballPathAnimator.start();
   }
 
   private void initBallSizeAnimator(Path path) {
-    BallSizeAnimator ballSizeAnimator =
+    ballSizeAnimator =
         new BallSizeAnimator(path, ballSizeAnimationDuration, minBallSize, maxBallSize);
     ballSizeAnimator.addBalls(balls);
-    ballSizeAnimator.start();
   }
 
   private void createBalls() {
@@ -115,6 +112,27 @@ private void createBalls() {
     }
   }
 
+  public void start() {
+    ballPathAnimator.start();
+    if (sizeAnimationEnabled) {
+      ballSizeAnimator.start();
+    }
+  }
+
+  public void stop() {
+    ballPathAnimator.stop();
+    if (sizeAnimationEnabled) {
+      ballSizeAnimator.start();
+    }
+  }
+
+  public void restart() {
+    ballPathAnimator.restart();
+    if (sizeAnimationEnabled) {
+      ballSizeAnimator.restart();
+    }
+  }
+
   @Override
   protected void onDraw(Canvas canvas) {
     for (Ball ball : balls) {

loadingballs/src/main/java/com/github/glomadrian/loadingballssample/animator/AbstractBallAnimator.java

@@ -7,7 +7,7 @@
 /**
  * @author Adrián García Lomas
  */
-public class AbstractBallAnimator {
+public abstract class AbstractBallAnimator {
 
   protected List<Ball> balls;
   protected BallAnimatorListener ballAnimatorListener;
@@ -28,6 +28,12 @@ public void setBallPathAnimatorListener(BallAnimatorListener ballAnimatorListene
     this.ballAnimatorListener = ballAnimatorListener;
   }
 
+  public abstract void start();
+
+  public abstract void stop();
+
+  public abstract void restart();
+
   public interface BallAnimatorListener {
 
     void onUpdate();

loadingballs/src/main/java/com/github/glomadrian/loadingballssample/animator/BallPathAnimator.java

@@ -50,12 +50,24 @@ private void initValueAnimator() {
     valueAnimator.addUpdateListener(this);
   }
 
+  @Override
   public void start() {
     float size = balls.size();
     offset = 1 / size;
     valueAnimator.start();
   }
 
+  @Override
+  public void stop(){
+    valueAnimator.cancel();
+  }
+
+  @Override
+  public void restart(){
+    stop();
+    start();
+  }
+
   @Override
   public void onAnimationUpdate(ValueAnimator animation) {
     float value = animation.getAnimatedFraction();

loadingballs/src/main/java/com/github/glomadrian/loadingballssample/animator/BallSizeAnimator.java

@@ -4,6 +4,8 @@
 import android.graphics.Path;
 import android.view.animation.AccelerateDecelerateInterpolator;
 import com.github.glomadrian.loadingballssample.Ball;
+import java.util.ArrayList;
+import java.util.List;
 
 /**
  * @author Adrián García Lomas
@@ -15,20 +17,40 @@ public class BallSizeAnimator extends AbstractBallAnimator {
   private Path path;
   private float minBallSize;
   private float maxBallSize;
+  private List<ValueAnimator> animators;
 
   public BallSizeAnimator(Path path, int duration, float minBallSize, float maxBallSize) {
     this.duration = duration;
     this.path = path;
     this.minBallSize = minBallSize;
     this.maxBallSize = maxBallSize;
+    init();
+  }
+
+  private void init() {
+    animators = new ArrayList<>();
   }
 
   public void start() {
+    animators.clear();
     for (int i = 0; i < balls.size(); i++) {
       createBallAnimatorAndStart(balls.get(i), 300 * i);
     }
   }
 
+  @Override
+  public void stop() {
+    for (ValueAnimator animator : animators) {
+      animator.cancel();
+    }
+  }
+
+  @Override
+  public void restart() {
+    stop();
+    start();
+  }
+
   private void createBallAnimatorAndStart(Ball ball, int startDelay) {
     ValueAnimator valueAnimator = new ValueAnimator();
     valueAnimator.setFloatValues(minBallSize, maxBallSize);
@@ -38,6 +60,7 @@ private void createBallAnimatorAndStart(Ball ball, int startDelay) {
     valueAnimator.setRepeatMode(ValueAnimator.REVERSE);
     valueAnimator.setRepeatCount(ValueAnimator.INFINITE);
     valueAnimator.setStartDelay(startDelay);
+    animators.add(valueAnimator);
     valueAnimator.start();
   }