[android_webview] Use a fraction to calculate scroll offset.

android_webview/java/src/org/chromium/android_webview/AwContents.java

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.android_webview;
 
 import android.content.pm.PackageManager;
 import android.content.res.Configuration;
 import android.graphics.Bitmap;
 import android.graphics.Canvas;
@@ skipping 167 matching lines @@
     // Bound method for suppling Picture instances to the AwContentsClient. Will be null if the
     // picture listener API has not yet been enabled, or if it is using invalidation-only mode.
     private Callable<Picture> mPictureListenerContentProvider;
 
     private boolean mContainerViewFocused;
     private boolean mWindowFocused;
 
     private boolean mClearViewActive;
     private boolean mPictureListenerEnabled;
 
+    // These come from the compositor and are updated immediately (in contrast to the values in
+    // ContentViewCore, which are updated at end of every frame).
+    private float mPageScaleFactor = 1.0f;
+    private float mContentWidthDip;
+    private float mContentHeightDip;
+
     private AwAutofillManagerDelegate mAwAutofillManagerDelegate;
 
     private static final class DestroyRunnable implements Runnable {
         private int mNativeAwContents;
         private DestroyRunnable(int nativeAwContents) {
             mNativeAwContents = nativeAwContents;
         }
         @Override
         public void run() {
             // This is a no-op if not currently attached.
@@ skipping 150 matching lines @@
             mInternalAccessAdapter.setMeasuredDimension(measuredWidth, measuredHeight);
         }
 
         @Override
         public void setFixedLayoutSize(int widthDip, int heightDip) {
             nativeSetFixedLayoutSize(mNativeAwContents, widthDip, heightDip);
         }
     }
 
     //--------------------------------------------------------------------------------------------
-    // NOTE: This content size change notification comes from the compositor and reflects the size
-    // of the content on screen (but not neccessarily in the renderer main thread).
-    private class AwContentUpdateFrameInfoListener
-                implements ContentViewCore.UpdateFrameInfoListener {
-        @Override
-        public void onFrameInfoUpdated(float widthCss, float heightCss, float pageScaleFactor) {
-            if (mNativeAwContents == 0) return;
-            int widthPix = (int) Math.floor(widthCss * mDIPScale * pageScaleFactor);
-            int heightPix = (int) Math.floor(heightCss * mDIPScale * pageScaleFactor);
-            mScrollOffsetManager.setContentSize(widthPix, heightPix);
-
-            nativeSetDisplayedPageScaleFactor(mNativeAwContents, pageScaleFactor);
-        }
-    }
-
-    //--------------------------------------------------------------------------------------------
     private class AwScrollOffsetManagerDelegate implements AwScrollOffsetManager.Delegate {
         @Override
         public void overScrollContainerViewBy(int deltaX, int deltaY, int scrollX, int scrollY,
                 int scrollRangeX, int scrollRangeY, boolean isTouchEvent) {
             mInternalAccessAdapter.overScrollBy(deltaX, deltaY, scrollX, scrollY,
                     scrollRangeX, scrollRangeY, 0, 0, isTouchEvent);
         }
 
         @Override
         public void scrollContainerViewTo(int x, int y) {
@@ skipping 176 matching lines @@
         mCleanupReference = new CleanupReference(this, new DestroyRunnable(mNativeAwContents));
 
         int nativeWebContents = nativeGetWebContents(mNativeAwContents);
         mContentViewCore = createAndInitializeContentViewCore(
                 mContainerView, mInternalAccessAdapter, nativeWebContents,
                 new AwGestureStateListener(), mContentsClient.getContentViewClient(),
                 mZoomControls);
         nativeSetJavaPeers(mNativeAwContents, this, mWebContentsDelegate, mContentsClientBridge,
                 mIoThreadClient, mInterceptNavigationDelegate);
         mContentsClient.installWebContentsObserver(mContentViewCore);
-        mContentViewCore.setUpdateFrameInfoListener(new AwContentUpdateFrameInfoListener());
         mSettings.setWebContents(nativeWebContents);
         nativeSetDipScale(mNativeAwContents, (float) mDIPScale);
         updateGlobalVisibleRect();
 
         // The only call to onShow. onHide should never be called.
         mContentViewCore.onShow();
    }
 
     /**
      * Called on the "source" AwContents that is opening the popup window to
@@ skipping 168 matching lines @@
                     mScrollOffsetManager.computeMaximumVerticalScrollOffset())) {
             mContainerView.invalidate();
         }
     }
 
     public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
         mLayoutSizer.onMeasure(widthMeasureSpec, heightMeasureSpec);
     }
 
     public int getContentHeightCss() {
-        return (int) Math.ceil(mContentViewCore.getContentHeightCss());
+        return (int) Math.ceil(mContentHeightDip);
     }
 
     public int getContentWidthCss() {
-        return (int) Math.ceil(mContentViewCore.getContentWidthCss());
+        return (int) Math.ceil(mContentWidthDip);
     }
 
     public Picture capturePicture() {
         if (mNativeAwContents == 0) return null;
         return new AwPicture(nativeCapturePicture(mNativeAwContents,
                     mScrollOffsetManager.computeHorizontalScrollRange(),
                     mScrollOffsetManager.computeVerticalScrollRange()));
     }
 
     public void clearView() {
@@ skipping 564 matching lines @@
         msg.sendToTarget();
     }
 
     /**
      * @see android.webkit.WebView#getScale()
      *
      * Please note that the scale returned is the page scale multiplied by
      * the screen density factor. See CTS WebViewTest.testSetInitialScale.
      */
     public float getScale() {
-        return (float)(mContentViewCore.getScale() * mDIPScale);
+        return (float)(mPageScaleFactor * mDIPScale);
     }
 
     /**
      * @see android.webkit.WebView#flingScroll(int, int)
      */
     public void flingScroll(int velocityX, int velocityY) {
         mScrollOffsetManager.flingScroll(velocityX, velocityY);
     }
 
     /**
@@ skipping 457 matching lines @@
         mLayoutSizer.onPageScaleChanged(webLayoutPageScaleFactor);
     }
 
     @CalledByNative
     private void onWebLayoutContentsSizeChanged(int widthCss, int heightCss) {
         // This change notification comes from the renderer thread, not from the cc/ impl thread.
         mLayoutSizer.onContentSizeChanged(widthCss, heightCss);
     }
 
     @CalledByNative
+    private void setMaxContainerViewScrollOffset(int maxX, int maxY) {
+        mScrollOffsetManager.setMaxScrollOffset(maxX, maxY);
+    }
+
+    @CalledByNative
     private void scrollContainerViewTo(int x, int y) {
         mScrollOffsetManager.scrollContainerViewTo(x, y);
     }
 
     @CalledByNative
+    private void setContentsSize(int widthDip, int heightDip) {
+        mContentWidthDip = widthDip;
+        mContentHeightDip = heightDip;
+    }
+
+    @CalledByNative
+    private void setPageScaleFactor(float pageScaleFactor) {
+        mPageScaleFactor = pageScaleFactor;
+    }
+
+    @CalledByNative
     private void setAwAutofillManagerDelegate(AwAutofillManagerDelegate delegate) {
         mAwAutofillManagerDelegate = delegate;
         delegate.init(mContentViewCore);
     }
 
     @CalledByNative
     private void didOverscroll(int deltaX, int deltaY) {
         if (mOverScrollGlow != null) {
             mOverScrollGlow.setOverScrollDeltas(deltaX, deltaY);
         }
@@ skipping 94 matching lines @@
     private native void nativeUpdateLastHitTestData(int nativeAwContents);
 
     private native void nativeOnSizeChanged(int nativeAwContents, int w, int h, int ow, int oh);
     private native void nativeScrollTo(int nativeAwContents, int x, int y);
     private native void nativeSetViewVisibility(int nativeAwContents, boolean visible);
     private native void nativeSetWindowVisibility(int nativeAwContents, boolean visible);
     private native void nativeSetIsPaused(int nativeAwContents, boolean paused);
     private native void nativeOnAttachedToWindow(int nativeAwContents, int w, int h);
     private static native void nativeOnDetachedFromWindow(int nativeAwContents);
     private native void nativeSetDipScale(int nativeAwContents, float dipScale);
-    private native void nativeSetDisplayedPageScaleFactor(int nativeAwContents,
-            float pageScaleFactor);
     private native void nativeSetFixedLayoutSize(int nativeAwContents, int widthDip, int heightDip);
 
     // Returns null if save state fails.
     private native byte[] nativeGetOpaqueState(int nativeAwContents);
 
     // Returns false if restore state fails.
     private native boolean nativeRestoreFromOpaqueState(int nativeAwContents, byte[] state);
 
     private native int nativeReleasePopupAwContents(int nativeAwContents);
     private native void nativeFocusFirstNode(int nativeAwContents);
     private native void nativeSetBackgroundColor(int nativeAwContents, int color);
 
     private native int nativeGetAwDrawGLViewContext(int nativeAwContents);
     private native int nativeCapturePicture(int nativeAwContents, int width, int height);
     private native void nativeEnableOnNewPicture(int nativeAwContents, boolean enabled);
 
     private native void nativeInvokeGeolocationCallback(
             int nativeAwContents, boolean value, String requestingFrame);
 
     private native void nativeSetJsOnlineProperty(int nativeAwContents, boolean networkUp);
 }