Add Android resolution limit to prevent crash on reder large bitmaps

Author: douglasjunior

README.md

@@ -78,6 +78,7 @@ For more details, see the [Sample Project](https://github.com/douglasjunior/reac
 |source|`string`||Path to a file stored on the device.|
 |distanceBetweenPages|`number`|`16`|Distance in `DPI` between pages.|
 |maxZoom|`number`|`5`|Max zoom scale.|
+|maxPageResolution|`number`|`2048`|(Android only) Max page resolution (width/height) when zooming. Defined to prevent Android crash when zooming too much: https://github.com/douglasjunior/react-native-pdf-renderer/issues/26 . |
 |singlePage|`boolean`|`false`|(Experimental) Renders only the first page without scroll. (useful for display thumbnail)|
 |onPageChange|`(current: number, total: number) => void`||Invoked on pages scroll.|
 |style|`StyleProp<ViewStyle>`||Styles to be applied to the native [view](https://reactnative.dev/docs/view-style-props).|

Sample/App.tsx

@@ -82,7 +82,8 @@ function App(): JSX.Element {
           style={{backgroundColor: 'red'}}
           source={source}
           distanceBetweenPages={16}
-          maxZoom={5}
+          maxZoom={20}
+          maxPageResolution={2048}
           singlePage={singlePage}
           onPageChange={(current, total) => {
             console.log('onPageChange', {current, total});

android/src/main/java/com/github/douglasjunior/reactNativePdfRenderer/modules/PdfRendererRecyclerView.java

@@ -64,6 +64,7 @@ public class PdfRendererRecyclerView extends RecyclerView {
     private final LayoutManager mLayoutManager;
     private boolean mRequestedLayout = false;
     private float mMaxZoom = 5;
+    private float mMaxPageResolution;
     private float mDistanceBetweenPages = 0;
     private int mWidth;
     private int mHeight;
@@ -104,6 +105,10 @@ public void setDistanceBetweenPages(float distanceBetweenPages) {
         );
     }
 
+    public void setMaxPageResolution(float maxPageResolution) {
+        this.mMaxPageResolution = maxPageResolution;
+    }
+
     public void setMaxZoom(float maxZoom) {
         this.mMaxZoom = maxZoom;
     }
@@ -153,7 +158,11 @@ private void dispatchPageChangeEvent() {
     protected void dispatchDraw(@NonNull Canvas canvas) {
         canvas.save();
         canvas.concat(mMatrix);
-        super.dispatchDraw(canvas);
+        try {
+            super.dispatchDraw(canvas);
+        } catch (Exception ex) {
+            Log.e("PdfRendererRecyclerView", "Error dispatching draw", ex);
+        }
         canvas.restore();
     }
 
@@ -409,13 +418,30 @@ public ImageView getImageView() {
                 return (ImageView) this.itemView;
             }
 
-            public void update(int position, float newZoom) {
-                var page = mPdfRenderer.openPage(position);
-                var bitmap = Bitmap.createBitmap(
-                        Math.round(page.getWidth() * newZoom),
-                        Math.round(page.getHeight() * newZoom),
+            private @NonNull Bitmap createBitmap(float newZoom, int pageWidth, int pageHeight) {
+                var scaledPageWidth = Math.round(pageWidth * newZoom);
+                var scaledPageHeight = Math.round(pageHeight * newZoom);
+
+                float scalingFactor = Math.min(
+                        mMaxPageResolution / scaledPageWidth,
+                        mMaxPageResolution / scaledPageHeight
+                );
+
+                float zoomFactor = Math.min(newZoom, scalingFactor);
+
+                return Bitmap.createBitmap(
+                        Math.round(scaledPageWidth * zoomFactor),
+                        Math.round(scaledPageHeight * zoomFactor),
                         Bitmap.Config.ARGB_4444
                 );
+            }
+
+            public void update(int position, float newZoom) {
+                var page = mPdfRenderer.openPage(position);
+                var pageWidth = page.getWidth();
+                var pageHeight = page.getHeight();
+                var bitmap = createBitmap(newZoom, pageWidth, pageHeight);
+
                 page.render(bitmap, null, null, PdfRenderer.Page.RENDER_MODE_FOR_DISPLAY);
 
                 var imageView = getImageView();
@@ -428,7 +454,7 @@ public void update(int position, float newZoom) {
                     lp.height = LayoutParams.MATCH_PARENT;
                     lp.setMargins(0, 0, 0, 0);
                 } else {
-                    lp.height = Math.round(((float) mWidth / (float) page.getWidth()) * (float) page.getHeight());
+                    lp.height = Math.round(((float) mWidth / (float) pageWidth) * (float) pageHeight);
                     lp.setMargins(0, 0, 0, (int) mDistanceBetweenPages);
                 }
                 imageView.setLayoutParams(lp);

android/src/main/java/com/github/douglasjunior/reactNativePdfRenderer/modules/PdfRendererViewManager.java

@@ -109,4 +109,10 @@ public void setDistanceBetweenPages(ViewGroup layout, @Nullable float distanceBe
         var recyclerView = (PdfRendererRecyclerView) layout.getChildAt(0);
         recyclerView.setDistanceBetweenPages(distanceBetweenPages);
     }
+
+    @ReactProp(name = "maxPageResolution")
+    public void setMaxPageResolution(ViewGroup layout, @Nullable float maxPageResolution) {
+        var recyclerView = (PdfRendererRecyclerView) layout.getChildAt(0);
+        recyclerView.setMaxPageResolution(maxPageResolution);
+    }
 }

package.json

@@ -1,7 +1,7 @@
 {
   "name": "react-native-pdf-renderer",
   "displayName": "React-Native Pdf Renderer",
-  "version": "1.3.2",
+  "version": "1.4.0",
   "description": "⚛ A zoomable, blazing fast, zero dependencies, pure native, typed PDF Renderer for Android and iOS.",
   "main": "src",
   "license": "MIT",