1 /*
2  * Copyright (C) 2012 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package android.webkit;
18 
19 import android.annotation.NonNull;
20 import android.annotation.Nullable;
21 import android.annotation.SuppressLint;
22 import android.annotation.SystemApi;
23 import android.content.Intent;
24 import android.content.res.Configuration;
25 import android.graphics.Bitmap;
26 import android.graphics.Canvas;
27 import android.graphics.Paint;
28 import android.graphics.Picture;
29 import android.graphics.Rect;
30 import android.graphics.drawable.Drawable;
31 import android.net.Uri;
32 import android.net.http.SslCertificate;
33 import android.os.Bundle;
34 import android.os.Handler;
35 import android.os.Message;
36 import android.print.PrintDocumentAdapter;
37 import android.util.LongSparseArray;
38 import android.util.SparseArray;
39 import android.view.DragEvent;
40 import android.view.KeyEvent;
41 import android.view.MotionEvent;
42 import android.view.PointerIcon;
43 import android.view.View;
44 import android.view.ViewGroup.LayoutParams;
45 import android.view.WindowInsets;
46 import android.view.accessibility.AccessibilityEvent;
47 import android.view.accessibility.AccessibilityNodeInfo;
48 import android.view.accessibility.AccessibilityNodeProvider;
49 import android.view.autofill.AutofillId;
50 import android.view.autofill.AutofillValue;
51 import android.view.inputmethod.EditorInfo;
52 import android.view.inputmethod.InputConnection;
53 import android.view.textclassifier.TextClassifier;
54 import android.view.translation.TranslationCapability;
55 import android.view.translation.TranslationSpec.DataFormat;
56 import android.view.translation.ViewTranslationRequest;
57 import android.view.translation.ViewTranslationResponse;
58 import android.webkit.WebView.HitTestResult;
59 import android.webkit.WebView.PictureListener;
60 import android.webkit.WebView.VisualStateCallback;
61 
62 
63 import java.io.BufferedWriter;
64 import java.io.File;
65 import java.util.List;
66 import java.util.Map;
67 import java.util.concurrent.Executor;
68 import java.util.function.Consumer;
69 
70 /**
71  * WebView backend provider interface: this interface is the abstract backend to a WebView
72  * instance; each WebView object is bound to exactly one WebViewProvider object which implements
73  * the runtime behavior of that WebView.
74  *
75  * All methods must behave as per their namesake in {@link WebView}, unless otherwise noted.
76  *
77  * @hide Not part of the public API; only required by system implementors.
78  */
79 @SystemApi
80 public interface WebViewProvider {
81     //-------------------------------------------------------------------------
82     // Main interface for backend provider of the WebView class.
83     //-------------------------------------------------------------------------
84     /**
85      * Initialize this WebViewProvider instance. Called after the WebView has fully constructed.
86      * @param javaScriptInterfaces is a Map of interface names, as keys, and
87      * object implementing those interfaces, as values.
88      * @param privateBrowsing If {@code true} the web view will be initialized in private /
89      * incognito mode.
90      */
init(Map<String, Object> javaScriptInterfaces, boolean privateBrowsing)91     public void init(Map<String, Object> javaScriptInterfaces,
92             boolean privateBrowsing);
93 
94     // Deprecated - should never be called
setHorizontalScrollbarOverlay(boolean overlay)95     public void setHorizontalScrollbarOverlay(boolean overlay);
96 
97     // Deprecated - should never be called
setVerticalScrollbarOverlay(boolean overlay)98     public void setVerticalScrollbarOverlay(boolean overlay);
99 
100     // Deprecated - should never be called
overlayHorizontalScrollbar()101     public boolean overlayHorizontalScrollbar();
102 
103     // Deprecated - should never be called
overlayVerticalScrollbar()104     public boolean overlayVerticalScrollbar();
105 
getVisibleTitleHeight()106     public int getVisibleTitleHeight();
107 
getCertificate()108     public SslCertificate getCertificate();
109 
setCertificate(SslCertificate certificate)110     public void setCertificate(SslCertificate certificate);
111 
savePassword(String host, String username, String password)112     public void savePassword(String host, String username, String password);
113 
setHttpAuthUsernamePassword(String host, String realm, String username, String password)114     public void setHttpAuthUsernamePassword(String host, String realm,
115             String username, String password);
116 
getHttpAuthUsernamePassword(String host, String realm)117     public String[] getHttpAuthUsernamePassword(String host, String realm);
118 
119     /**
120      * See {@link WebView#destroy()}.
121      * As well as releasing the internal state and resources held by the implementation,
122      * the provider should null all references it holds on the WebView proxy class, and ensure
123      * no further method calls are made to it.
124      */
destroy()125     public void destroy();
126 
setNetworkAvailable(boolean networkUp)127     public void setNetworkAvailable(boolean networkUp);
128 
saveState(Bundle outState)129     public WebBackForwardList saveState(Bundle outState);
130 
savePicture(Bundle b, final File dest)131     public boolean savePicture(Bundle b, final File dest);
132 
restorePicture(Bundle b, File src)133     public boolean restorePicture(Bundle b, File src);
134 
restoreState(Bundle inState)135     public WebBackForwardList restoreState(Bundle inState);
136 
loadUrl(String url, Map<String, String> additionalHttpHeaders)137     public void loadUrl(String url, Map<String, String> additionalHttpHeaders);
138 
loadUrl(String url)139     public void loadUrl(String url);
140 
postUrl(String url, byte[] postData)141     public void postUrl(String url, byte[] postData);
142 
loadData(String data, String mimeType, String encoding)143     public void loadData(String data, String mimeType, String encoding);
144 
loadDataWithBaseURL(String baseUrl, String data, String mimeType, String encoding, String historyUrl)145     public void loadDataWithBaseURL(String baseUrl, String data,
146             String mimeType, String encoding, String historyUrl);
147 
evaluateJavaScript(String script, ValueCallback<String> resultCallback)148     public void evaluateJavaScript(String script, ValueCallback<String> resultCallback);
149 
saveWebArchive(String filename)150     public void saveWebArchive(String filename);
151 
saveWebArchive(String basename, boolean autoname, ValueCallback<String> callback)152     public void saveWebArchive(String basename, boolean autoname, ValueCallback<String> callback);
153 
stopLoading()154     public void stopLoading();
155 
reload()156     public void reload();
157 
canGoBack()158     public boolean canGoBack();
159 
goBack()160     public void goBack();
161 
canGoForward()162     public boolean canGoForward();
163 
goForward()164     public void goForward();
165 
canGoBackOrForward(int steps)166     public boolean canGoBackOrForward(int steps);
167 
goBackOrForward(int steps)168     public void goBackOrForward(int steps);
169 
isPrivateBrowsingEnabled()170     public boolean isPrivateBrowsingEnabled();
171 
pageUp(boolean top)172     public boolean pageUp(boolean top);
173 
pageDown(boolean bottom)174     public boolean pageDown(boolean bottom);
175 
insertVisualStateCallback(long requestId, VisualStateCallback callback)176     public void insertVisualStateCallback(long requestId, VisualStateCallback callback);
177 
clearView()178     public void clearView();
179 
capturePicture()180     public Picture capturePicture();
181 
createPrintDocumentAdapter(String documentName)182     public PrintDocumentAdapter createPrintDocumentAdapter(String documentName);
183 
getScale()184     public float getScale();
185 
setInitialScale(int scaleInPercent)186     public void setInitialScale(int scaleInPercent);
187 
invokeZoomPicker()188     public void invokeZoomPicker();
189 
getHitTestResult()190     public HitTestResult getHitTestResult();
191 
requestFocusNodeHref(Message hrefMsg)192     public void requestFocusNodeHref(Message hrefMsg);
193 
requestImageRef(Message msg)194     public void requestImageRef(Message msg);
195 
getUrl()196     public String getUrl();
197 
getOriginalUrl()198     public String getOriginalUrl();
199 
getTitle()200     public String getTitle();
201 
getFavicon()202     public Bitmap getFavicon();
203 
getTouchIconUrl()204     public String getTouchIconUrl();
205 
getProgress()206     public int getProgress();
207 
getContentHeight()208     public int getContentHeight();
209 
getContentWidth()210     public int getContentWidth();
211 
pauseTimers()212     public void pauseTimers();
213 
resumeTimers()214     public void resumeTimers();
215 
onPause()216     public void onPause();
217 
onResume()218     public void onResume();
219 
isPaused()220     public boolean isPaused();
221 
freeMemory()222     public void freeMemory();
223 
clearCache(boolean includeDiskFiles)224     public void clearCache(boolean includeDiskFiles);
225 
clearFormData()226     public void clearFormData();
227 
clearHistory()228     public void clearHistory();
229 
clearSslPreferences()230     public void clearSslPreferences();
231 
copyBackForwardList()232     public WebBackForwardList copyBackForwardList();
233 
setFindListener(WebView.FindListener listener)234     public void setFindListener(WebView.FindListener listener);
235 
findNext(boolean forward)236     public void findNext(boolean forward);
237 
findAll(String find)238     public int findAll(String find);
239 
findAllAsync(String find)240     public void findAllAsync(String find);
241 
showFindDialog(String text, boolean showIme)242     public boolean showFindDialog(String text, boolean showIme);
243 
clearMatches()244     public void clearMatches();
245 
documentHasImages(Message response)246     public void documentHasImages(Message response);
247 
setWebViewClient(WebViewClient client)248     public void setWebViewClient(WebViewClient client);
249 
getWebViewClient()250     public WebViewClient getWebViewClient();
251 
252     @Nullable
getWebViewRenderProcess()253     public WebViewRenderProcess getWebViewRenderProcess();
254 
setWebViewRenderProcessClient( @ullable Executor executor, @Nullable WebViewRenderProcessClient client)255     public void setWebViewRenderProcessClient(
256             @Nullable Executor executor,
257             @Nullable WebViewRenderProcessClient client);
258 
259     @Nullable
getWebViewRenderProcessClient()260     public WebViewRenderProcessClient getWebViewRenderProcessClient();
261 
setDownloadListener(DownloadListener listener)262     public void setDownloadListener(DownloadListener listener);
263 
setWebChromeClient(WebChromeClient client)264     public void setWebChromeClient(WebChromeClient client);
265 
getWebChromeClient()266     public WebChromeClient getWebChromeClient();
267 
setPictureListener(PictureListener listener)268     public void setPictureListener(PictureListener listener);
269 
addJavascriptInterface(Object obj, String interfaceName)270     public void addJavascriptInterface(Object obj, String interfaceName);
271 
removeJavascriptInterface(String interfaceName)272     public void removeJavascriptInterface(String interfaceName);
273 
createWebMessageChannel()274     public WebMessagePort[] createWebMessageChannel();
275 
postMessageToMainFrame(WebMessage message, Uri targetOrigin)276     public void postMessageToMainFrame(WebMessage message, Uri targetOrigin);
277 
getSettings()278     public WebSettings getSettings();
279 
setMapTrackballToArrowKeys(boolean setMap)280     public void setMapTrackballToArrowKeys(boolean setMap);
281 
flingScroll(int vx, int vy)282     public void flingScroll(int vx, int vy);
283 
getZoomControls()284     public View getZoomControls();
285 
canZoomIn()286     public boolean canZoomIn();
287 
canZoomOut()288     public boolean canZoomOut();
289 
zoomBy(float zoomFactor)290     public boolean zoomBy(float zoomFactor);
291 
zoomIn()292     public boolean zoomIn();
293 
zoomOut()294     public boolean zoomOut();
295 
dumpViewHierarchyWithProperties(BufferedWriter out, int level)296     public void dumpViewHierarchyWithProperties(BufferedWriter out, int level);
297 
findHierarchyView(String className, int hashCode)298     public View findHierarchyView(String className, int hashCode);
299 
setRendererPriorityPolicy(int rendererRequestedPriority, boolean waivedWhenNotVisible)300     public void setRendererPriorityPolicy(int rendererRequestedPriority, boolean waivedWhenNotVisible);
301 
getRendererRequestedPriority()302     public int getRendererRequestedPriority();
303 
getRendererPriorityWaivedWhenNotVisible()304     public boolean getRendererPriorityWaivedWhenNotVisible();
305 
306     @SuppressWarnings("unused")
setTextClassifier(@ullable TextClassifier textClassifier)307     public default void setTextClassifier(@Nullable TextClassifier textClassifier) {}
308 
309     @NonNull
getTextClassifier()310     public default TextClassifier getTextClassifier() { return TextClassifier.NO_OP; }
311 
312     //-------------------------------------------------------------------------
313     // Provider internal methods
314     //-------------------------------------------------------------------------
315 
316     /**
317      * @return the ViewDelegate implementation. This provides the functionality to back all of
318      * the name-sake functions from the View and ViewGroup base classes of WebView.
319      */
getViewDelegate()320     /* package */ ViewDelegate getViewDelegate();
321 
322     /**
323      * @return a ScrollDelegate implementation. Normally this would be same object as is
324      * returned by getViewDelegate().
325      */
getScrollDelegate()326     /* package */ ScrollDelegate getScrollDelegate();
327 
328     /**
329      * Only used by FindActionModeCallback to inform providers that the find dialog has
330      * been dismissed.
331      */
notifyFindDialogDismissed()332     public void notifyFindDialogDismissed();
333 
334     //-------------------------------------------------------------------------
335     // View / ViewGroup delegation methods
336     //-------------------------------------------------------------------------
337 
338     /**
339      * Provides mechanism for the name-sake methods declared in View and ViewGroup to be delegated
340      * into the WebViewProvider instance.
341      * NOTE: For many of these methods, the WebView will provide a super.Foo() call before or after
342      * making the call into the provider instance. This is done for convenience in the common case
343      * of maintaining backward compatibility. For remaining super class calls (e.g. where the
344      * provider may need to only conditionally make the call based on some internal state) see the
345      * {@link WebView.PrivateAccess} callback class.
346      */
347     // TODO: See if the pattern of the super-class calls can be rationalized at all, and document
348     // the remainder on the methods below.
349     interface ViewDelegate {
shouldDelayChildPressedState()350         public boolean shouldDelayChildPressedState();
351 
onProvideVirtualStructure(android.view.ViewStructure structure)352         public void onProvideVirtualStructure(android.view.ViewStructure structure);
353 
onProvideAutofillVirtualStructure( @uppressWarnings"unused") android.view.ViewStructure structure, @SuppressWarnings("unused") int flags)354         default void onProvideAutofillVirtualStructure(
355                 @SuppressWarnings("unused") android.view.ViewStructure structure,
356                 @SuppressWarnings("unused") int flags) {
357         }
358 
autofill(@uppressWarnings"unused") SparseArray<AutofillValue> values)359         default void autofill(@SuppressWarnings("unused") SparseArray<AutofillValue> values) {
360         }
361 
isVisibleToUserForAutofill(@uppressWarnings"unused") int virtualId)362         default boolean isVisibleToUserForAutofill(@SuppressWarnings("unused") int virtualId) {
363             return true; // true is the default value returned by View.isVisibleToUserForAutofill()
364         }
365 
onProvideContentCaptureStructure( @onNull @uppressWarnings"unused") android.view.ViewStructure structure, @SuppressWarnings("unused") int flags)366         default void onProvideContentCaptureStructure(
367                 @NonNull @SuppressWarnings("unused") android.view.ViewStructure structure,
368                 @SuppressWarnings("unused") int flags) {
369         }
370 
371         @SuppressLint("NullableCollection")
onCreateVirtualViewTranslationRequests( @onNull @uppressWarnings"unused") long[] virtualIds, @NonNull @SuppressWarnings("unused") @DataFormat int[] supportedFormats, @NonNull @SuppressWarnings("unused") Consumer<ViewTranslationRequest> requestsCollector)372         default void onCreateVirtualViewTranslationRequests(
373                 @NonNull @SuppressWarnings("unused") long[] virtualIds,
374                 @NonNull @SuppressWarnings("unused") @DataFormat int[] supportedFormats,
375                 @NonNull @SuppressWarnings("unused")
376                         Consumer<ViewTranslationRequest> requestsCollector) {
377         }
378 
onVirtualViewTranslationResponses( @onNull @uppressWarnings"unused") LongSparseArray<ViewTranslationResponse> response)379         default void onVirtualViewTranslationResponses(
380                 @NonNull @SuppressWarnings("unused")
381                         LongSparseArray<ViewTranslationResponse> response) {
382         }
383 
dispatchCreateViewTranslationRequest( @onNull @uppressWarnings"unused") Map<AutofillId, long[]> viewIds, @NonNull @SuppressWarnings("unused") @DataFormat int[] supportedFormats, @Nullable @SuppressWarnings("unused") TranslationCapability capability, @NonNull @SuppressWarnings("unused") List<ViewTranslationRequest> requests)384         default void dispatchCreateViewTranslationRequest(
385                 @NonNull @SuppressWarnings("unused") Map<AutofillId, long[]> viewIds,
386                 @NonNull @SuppressWarnings("unused") @DataFormat int[] supportedFormats,
387                 @Nullable @SuppressWarnings("unused") TranslationCapability capability,
388                 @NonNull @SuppressWarnings("unused") List<ViewTranslationRequest> requests) {
389 
390         }
391 
getAccessibilityNodeProvider()392         public AccessibilityNodeProvider getAccessibilityNodeProvider();
393 
onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info)394         public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info);
395 
onInitializeAccessibilityEvent(AccessibilityEvent event)396         public void onInitializeAccessibilityEvent(AccessibilityEvent event);
397 
performAccessibilityAction(int action, Bundle arguments)398         public boolean performAccessibilityAction(int action, Bundle arguments);
399 
setOverScrollMode(int mode)400         public void setOverScrollMode(int mode);
401 
setScrollBarStyle(int style)402         public void setScrollBarStyle(int style);
403 
onDrawVerticalScrollBar(Canvas canvas, Drawable scrollBar, int l, int t, int r, int b)404         public void onDrawVerticalScrollBar(Canvas canvas, Drawable scrollBar, int l, int t,
405                 int r, int b);
406 
onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY)407         public void onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY);
408 
onWindowVisibilityChanged(int visibility)409         public void onWindowVisibilityChanged(int visibility);
410 
onDraw(Canvas canvas)411         public void onDraw(Canvas canvas);
412 
setLayoutParams(LayoutParams layoutParams)413         public void setLayoutParams(LayoutParams layoutParams);
414 
performLongClick()415         public boolean performLongClick();
416 
onConfigurationChanged(Configuration newConfig)417         public void onConfigurationChanged(Configuration newConfig);
418 
onCreateInputConnection(EditorInfo outAttrs)419         public InputConnection onCreateInputConnection(EditorInfo outAttrs);
420 
onDragEvent(DragEvent event)421         public boolean onDragEvent(DragEvent event);
422 
onKeyMultiple(int keyCode, int repeatCount, KeyEvent event)423         public boolean onKeyMultiple(int keyCode, int repeatCount, KeyEvent event);
424 
onKeyDown(int keyCode, KeyEvent event)425         public boolean onKeyDown(int keyCode, KeyEvent event);
426 
onKeyUp(int keyCode, KeyEvent event)427         public boolean onKeyUp(int keyCode, KeyEvent event);
428 
onAttachedToWindow()429         public void onAttachedToWindow();
430 
onDetachedFromWindow()431         public void onDetachedFromWindow();
432 
onMovedToDisplay(int displayId, Configuration config)433         public default void onMovedToDisplay(int displayId, Configuration config) {}
434 
onVisibilityChanged(View changedView, int visibility)435         public void onVisibilityChanged(View changedView, int visibility);
436 
onWindowFocusChanged(boolean hasWindowFocus)437         public void onWindowFocusChanged(boolean hasWindowFocus);
438 
onFocusChanged(boolean focused, int direction, Rect previouslyFocusedRect)439         public void onFocusChanged(boolean focused, int direction, Rect previouslyFocusedRect);
440 
setFrame(int left, int top, int right, int bottom)441         public boolean setFrame(int left, int top, int right, int bottom);
442 
onSizeChanged(int w, int h, int ow, int oh)443         public void onSizeChanged(int w, int h, int ow, int oh);
444 
onScrollChanged(int l, int t, int oldl, int oldt)445         public void onScrollChanged(int l, int t, int oldl, int oldt);
446 
dispatchKeyEvent(KeyEvent event)447         public boolean dispatchKeyEvent(KeyEvent event);
448 
onTouchEvent(MotionEvent ev)449         public boolean onTouchEvent(MotionEvent ev);
450 
onHoverEvent(MotionEvent event)451         public boolean onHoverEvent(MotionEvent event);
452 
onGenericMotionEvent(MotionEvent event)453         public boolean onGenericMotionEvent(MotionEvent event);
454 
onTrackballEvent(MotionEvent ev)455         public boolean onTrackballEvent(MotionEvent ev);
456 
requestFocus(int direction, Rect previouslyFocusedRect)457         public boolean requestFocus(int direction, Rect previouslyFocusedRect);
458 
onMeasure(int widthMeasureSpec, int heightMeasureSpec)459         public void onMeasure(int widthMeasureSpec, int heightMeasureSpec);
460 
requestChildRectangleOnScreen(View child, Rect rect, boolean immediate)461         public boolean requestChildRectangleOnScreen(View child, Rect rect, boolean immediate);
462 
setBackgroundColor(int color)463         public void setBackgroundColor(int color);
464 
setLayerType(int layerType, Paint paint)465         public void setLayerType(int layerType, Paint paint);
466 
preDispatchDraw(Canvas canvas)467         public void preDispatchDraw(Canvas canvas);
468 
onStartTemporaryDetach()469         public void onStartTemporaryDetach();
470 
onFinishTemporaryDetach()471         public void onFinishTemporaryDetach();
472 
onActivityResult(int requestCode, int resultCode, Intent data)473         public void onActivityResult(int requestCode, int resultCode, Intent data);
474 
getHandler(Handler originalHandler)475         public Handler getHandler(Handler originalHandler);
476 
findFocus(View originalFocusedView)477         public View findFocus(View originalFocusedView);
478 
479         @SuppressWarnings("unused")
onCheckIsTextEditor()480         default boolean onCheckIsTextEditor() {
481             return false;
482         }
483 
484         /**
485          * @see View#onApplyWindowInsets(WindowInsets).
486          *
487          * <p>This is the entry point for the WebView implementation to override. It returns
488          * {@code null} when the WebView implementation hasn't implemented the WindowInsets support
489          * on S yet. In this case, the {@link View#onApplyWindowInsets()} super method will be
490          * called instead.
491          *
492          * @param insets Insets to apply
493          * @return The supplied insets with any applied insets consumed.
494          */
495         @SuppressWarnings("unused")
496         @Nullable
onApplyWindowInsets(@ullable WindowInsets insets)497         default WindowInsets onApplyWindowInsets(@Nullable WindowInsets insets) {
498             return null;
499         }
500 
501         /**
502          * @hide Only used by WebView.
503          */
504         @SuppressWarnings("unused")
505         @Nullable
onResolvePointerIcon(@onNull MotionEvent event, int pointerIndex)506         default PointerIcon onResolvePointerIcon(@NonNull MotionEvent event, int pointerIndex) {
507             return null;
508         }
509     }
510 
511     interface ScrollDelegate {
512         // These methods are declared protected in the ViewGroup base class. This interface
513         // exists to promote them to public so they may be called by the WebView proxy class.
514         // TODO: Combine into ViewDelegate?
515         /**
516          * See {@link android.webkit.WebView#computeHorizontalScrollRange}
517          */
computeHorizontalScrollRange()518         public int computeHorizontalScrollRange();
519 
520         /**
521          * See {@link android.webkit.WebView#computeHorizontalScrollOffset}
522          */
computeHorizontalScrollOffset()523         public int computeHorizontalScrollOffset();
524 
525         /**
526          * See {@link android.webkit.WebView#computeVerticalScrollRange}
527          */
computeVerticalScrollRange()528         public int computeVerticalScrollRange();
529 
530         /**
531          * See {@link android.webkit.WebView#computeVerticalScrollOffset}
532          */
computeVerticalScrollOffset()533         public int computeVerticalScrollOffset();
534 
535         /**
536          * See {@link android.webkit.WebView#computeVerticalScrollExtent}
537          */
computeVerticalScrollExtent()538         public int computeVerticalScrollExtent();
539 
540         /**
541          * See {@link android.webkit.WebView#computeScroll}
542          */
computeScroll()543         public void computeScroll();
544     }
545 }
546