[core, darwin, android] Add onDidEnterIdle to MapObserver.

didEnterIdle fires whenever render completes and no repaint is scheduled.

3 files changed, 29 insertions, 0 deletions

diff --git a/platform/macos/src/MGLMapView.mm b/platform/macos/src/MGLMapView.mm
index 2f379ab406..eb877216d2 100644
--- a/platform/macos/src/MGLMapView.mm
+++ b/platform/macos/src/MGLMapView.mm
@@ -934,6 +934,16 @@ public:
     }
 }
 
+- (void)mapViewDidEnterIdle {
+    if (!_mbglMap) {
+        return;
+    }
+    
+    if ([self.delegate respondsToSelector:@selector(mapViewDidEnterIdle)]) {
+        [self.delegate mapViewDidEnterIdle:self];
+    }
+}
+
 - (void)mapViewDidFinishLoadingStyle {
     if (!_mbglMap) {
         return;
@@ -3050,6 +3060,10 @@ public:
         bool fullyRendered = mode == mbgl::MapObserver::RenderMode::Full;
         [nativeView mapViewDidFinishRenderingMapFullyRendered:fullyRendered];
     }
+    
+    void onDidEnterIdle() override {
+        [nativeView mapViewDidEnterIdle];
+    }
 
     void onDidFinishLoadingStyle() override {
         [nativeView mapViewDidFinishLoadingStyle];
diff --git a/platform/macos/src/MGLMapViewDelegate.h b/platform/macos/src/MGLMapViewDelegate.h
index 2a8b28c1b4..ad59f5bd39 100644
--- a/platform/macos/src/MGLMapViewDelegate.h
+++ b/platform/macos/src/MGLMapViewDelegate.h
@@ -152,6 +152,19 @@ NS_ASSUME_NONNULL_BEGIN
 - (void)mapViewDidFinishRenderingFrame:(MGLMapView *)mapView fullyRendered:(BOOL)fullyRendered;
 
 /**
+ Tells the delegate that the map view is entering an idle state, and no more
+ drawing will be necessary until new data is loaded or there is some interaction
+ with the map.
+ 
+ - No camera transitions are in progress
+ - All currently requested tiles have loaded
+ - All fade/transition animations have completed
+ 
+ @param mapView The map view that has just entered the idle state.
+ */
+- (void)mapViewDidEnterIdle:(MGLMapView *)mapView;
+
+/**
  Tells the delegate that the map has just finished loading a style.
 
  This method is called during the initialization of the map view and after any
diff --git a/platform/macos/test/MGLMapViewDelegateIntegrationTests.swift b/platform/macos/test/MGLMapViewDelegateIntegrationTests.swift
index 00635d97eb..109c279a09 100644
--- a/platform/macos/test/MGLMapViewDelegateIntegrationTests.swift
+++ b/platform/macos/test/MGLMapViewDelegateIntegrationTests.swift
@@ -24,6 +24,8 @@ extension MGLMapViewDelegateIntegrationTests: MGLMapViewDelegate {
     func mapViewDidFinishRenderingFrame(_ mapView: MGLMapView, fullyRendered: Bool) {}
 
     func mapViewDidFinishRenderingMap(_ mapView: MGLMapView, fullyRendered: Bool) {}
+    
+    func mapViewDidEnterIdle(_ mapView: MGLMapView) {}
 
     func mapViewDidFailLoadingMap(_ mapView: MGLMapView, withError error: Error) {}