fix(zoomimage): android fix for current zoom being reset on updateImageUri

Author: farfromrefug

packages/zoomimage/platforms/android/java/com/facebook/samples/zoomable/DefaultZoomableController.java

@@ -72,6 +72,10 @@ public interface ImageBoundsListener {
   private final RectF mTempRect = new RectF();
   private boolean mWasTransformCorrected;
 
+  // used to not reset transform on updateImageUri ( controller update )
+  public boolean ignoreNextResetUntilEnabled = false;
+
+
   public static DefaultZoomableController newInstance() {
     return new DefaultZoomableController(TransformGestureDetector.newInstance());
   }
@@ -83,6 +87,9 @@ public DefaultZoomableController(TransformGestureDetector gestureDetector) {
 
   /** Rests the controller. */
   public void reset() {
+    if (ignoreNextResetUntilEnabled) {
+      return;
+    }
     mGestureDetector.reset();
     mPreviousTransform.reset();
     mActiveTransform.reset();
@@ -101,6 +108,8 @@ public void setEnabled(boolean enabled) {
     mIsEnabled = enabled;
     if (!enabled) {
       reset();
+    } else {
+      ignoreNextResetUntilEnabled = false;
     }
   }
 

src/zoomimage/index.android.ts

@@ -18,6 +18,11 @@ export class ZoomImg extends ZoomImageBase {
         return this.nativeViewProtected?.getZoomableController() as com.facebook.samples.zoomable.DefaultZoomableController;
     }
 
+    updateImageUri() {
+        // this prevents the controller from reseting the current transform
+        this.getController().ignoreNextResetUntilEnabled = true;
+        return super.updateImageUri();
+    }
     [zoomScaleProperty.setNative](scale: number) {
         //possible?
         // if (this.nativeViewProtected) {

src/zoomimage/typings/android.d.ts

@@ -213,6 +213,7 @@ declare namespace com {
                     public static LIMIT_TRANSLATION_Y: number = 2;
                     public static LIMIT_SCALE: number = 4;
                     public static LIMIT_ALL: number = 7;
+                    public ignoreNextResetUntilEnabled : boolean;
                     public mapViewToImage(param0: globalAndroid.graphics.PointF): globalAndroid.graphics.PointF;
                     public isIdentity(): boolean;
                     public wasTransformCorrected(): boolean;