[android] expose symbol placement transition duration option

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/Style.java

@@ -375,9 +375,16 @@ public class Style {
 
   /**
    * <p>
-   * Set the transition duration for style changes.
+   * Set the transition options for style changes.
    * </p>
-   * The default value for delay and duration is zero, so any changes take effect without animation.
+   * If not set, any changes take effect without animation, besides symbols,
+   * which will fade in/out with a default duration after symbol collision detection.
+   * <p>
+   * To disable symbols fade in/out animation,
+   * pass transition options with {@link TransitionOptions#enablePlacementTransitions} equal to false.
+   * <p>
+   * Both {@link TransitionOptions#duration} and {@link TransitionOptions#delay}
+   * will also change the behavior of the symbols fade in/out animation if the placement transition is enabled.
    *
    * @param transitionOptions the transition options
    */
@@ -388,9 +395,17 @@ public class Style {
 
   /**
    * <p>
-   * Get the transition for style changes.
+   * Get the transition options for style changes.
    * </p>
-   * The default value for delay and transition is zero, so any changes take effect without animation.
+   * By default, any changes take effect without animation, besides symbols,
+   * which will fade in/out with a default duration after symbol collision detection.
+   * <p>
+   * To disable symbols fade in/out animation,
+   * pass transition options with {@link TransitionOptions#enablePlacementTransitions} equal to false
+   * into {@link #setTransition(TransitionOptions)}.
+   * <p>
+   * Both {@link TransitionOptions#duration} and {@link TransitionOptions#delay}
+   * will also change the behavior of the symbols fade in/out animation if the placement transition is enabled.
    *
    * @return TransitionOptions the transition options
    */

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/TransitionOptions.java

@@ -1,8 +1,6 @@
 package com.mapbox.mapboxsdk.style.layers;
 
 import android.support.annotation.Keep;
-import android.support.annotation.NonNull;
-import android.support.annotation.Nullable;
 
 /**
  * Resembles transition property from the style specification.
@@ -15,6 +13,8 @@ public class TransitionOptions {
   private long duration;
   @Keep
   private long delay;
+  @Keep
+  private boolean enablePlacementTransitions;
 
   /**
    * Create a transition property based on duration and a delay.
@@ -23,8 +23,21 @@ public class TransitionOptions {
    * @param delay    the delay to start the transition
    */
   public TransitionOptions(long duration, long delay) {
+    this(duration, delay, true);
+  }
+
+  /**
+   * Create a transition property.
+   *
+   * @param duration                   the duration of the transition
+   * @param delay                      the delay to start the transition
+   * @param enablePlacementTransitions the flag that describes whether the fade in/out symbol placement transition
+   *                                   should be enabled. Defaults to true.
+   */
+  public TransitionOptions(long duration, long delay, boolean enablePlacementTransitions) {
     this.duration = duration;
     this.delay = delay;
+    this.enablePlacementTransitions = enablePlacementTransitions;
   }
 
   /**
@@ -33,12 +46,30 @@ public class TransitionOptions {
    * @param duration the duration of the transition
    * @param delay    the delay to start the transition
    * @return a new transition property object
+   * @deprecated use {@link #fromTransitionOptions(long, long, boolean)} instead
    */
   @Keep
+  @Deprecated
   public static TransitionOptions fromTransitionOptions(long duration, long delay) {
+    // Invoked from JNI only
     return new TransitionOptions(duration, delay);
   }
 
+  /**
+   * Create a transition property.
+   *
+   * @param duration                   the duration of the transition
+   * @param delay                      the delay to start the transition
+   * @param enablePlacementTransitions the flag that describes whether the fade in/out symbol placement transition
+   *                                   should be enabled. Defaults to true.
+   * @return a new transition property object
+   */
+  @Keep
+  static TransitionOptions fromTransitionOptions(long duration, long delay, boolean enablePlacementTransitions) {
+    // Invoked from JNI only
+    return new TransitionOptions(duration, delay, enablePlacementTransitions);
+  }
+
   /**
    * Get the transition duration.
    *
@@ -57,8 +88,17 @@ public class TransitionOptions {
     return delay;
   }
 
+  /**
+   * Get the flag that describes whether the fade in/out symbol placement transition should be enabled.
+   *
+   * @return true if the fade in/out symbol placement transition should be enabled, false otherwise
+   */
+  public boolean isEnablePlacementTransitions() {
+    return enablePlacementTransitions;
+  }
+
   @Override
-  public boolean equals(@Nullable Object o) {
+  public boolean equals(Object o) {
     if (this == o) {
       return true;
     }
@@ -71,22 +111,26 @@ public class TransitionOptions {
     if (duration != that.duration) {
       return false;
     }
-    return delay == that.delay;
+    if (delay != that.delay) {
+      return false;
+    }
+    return enablePlacementTransitions == that.enablePlacementTransitions;
   }
 
   @Override
   public int hashCode() {
     int result = (int) (duration ^ (duration >>> 32));
     result = 31 * result + (int) (delay ^ (delay >>> 32));
+    result = 31 * result + (enablePlacementTransitions ? 1 : 0);
     return result;
   }
 
-  @NonNull
   @Override
   public String toString() {
     return "TransitionOptions{"
       + "duration=" + duration
       + ", delay=" + delay
+      + ", enablePlacementTransitions=" + enablePlacementTransitions
       + '}';
   }
 }