Java tutorial
/* * Copyright (C) 2012 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package android.webkit; import android.annotation.NonNull; import android.annotation.Nullable; import android.annotation.SystemApi; import android.content.Intent; import android.content.res.Configuration; import android.graphics.Bitmap; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.Picture; import android.graphics.Rect; import android.graphics.drawable.Drawable; import android.net.Uri; import android.net.http.SslCertificate; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.print.PrintDocumentAdapter; import android.util.SparseArray; import android.view.DragEvent; import android.view.KeyEvent; import android.view.MotionEvent; import android.view.View; import android.view.ViewGroup.LayoutParams; import android.view.accessibility.AccessibilityEvent; import android.view.accessibility.AccessibilityNodeInfo; import android.view.accessibility.AccessibilityNodeProvider; import android.view.autofill.AutofillValue; import android.view.inputmethod.EditorInfo; import android.view.inputmethod.InputConnection; import android.view.textclassifier.TextClassifier; import android.webkit.WebView.HitTestResult; import android.webkit.WebView.PictureListener; import android.webkit.WebView.VisualStateCallback; import java.io.BufferedWriter; import java.io.File; import java.util.Map; /** * WebView backend provider interface: this interface is the abstract backend to a WebView * instance; each WebView object is bound to exactly one WebViewProvider object which implements * the runtime behavior of that WebView. * * All methods must behave as per their namesake in {@link WebView}, unless otherwise noted. * * @hide Not part of the public API; only required by system implementors. */ @SystemApi public interface WebViewProvider { //------------------------------------------------------------------------- // Main interface for backend provider of the WebView class. //------------------------------------------------------------------------- /** * Initialize this WebViewProvider instance. Called after the WebView has fully constructed. * @param javaScriptInterfaces is a Map of interface names, as keys, and * object implementing those interfaces, as values. * @param privateBrowsing If {@code true} the web view will be initialized in private / * incognito mode. */ public void init(Map<String, Object> javaScriptInterfaces, boolean privateBrowsing); // Deprecated - should never be called public void setHorizontalScrollbarOverlay(boolean overlay); // Deprecated - should never be called public void setVerticalScrollbarOverlay(boolean overlay); // Deprecated - should never be called public boolean overlayHorizontalScrollbar(); // Deprecated - should never be called public boolean overlayVerticalScrollbar(); public int getVisibleTitleHeight(); public SslCertificate getCertificate(); public void setCertificate(SslCertificate certificate); public void savePassword(String host, String username, String password); public void setHttpAuthUsernamePassword(String host, String realm, String username, String password); public String[] getHttpAuthUsernamePassword(String host, String realm); /** * See {@link WebView#destroy()}. * As well as releasing the internal state and resources held by the implementation, * the provider should null all references it holds on the WebView proxy class, and ensure * no further method calls are made to it. */ public void destroy(); public void setNetworkAvailable(boolean networkUp); public WebBackForwardList saveState(Bundle outState); public boolean savePicture(Bundle b, final File dest); public boolean restorePicture(Bundle b, File src); public WebBackForwardList restoreState(Bundle inState); public void loadUrl(String url, Map<String, String> additionalHttpHeaders); public void loadUrl(String url); public void postUrl(String url, byte[] postData); public void loadData(String data, String mimeType, String encoding); public void loadDataWithBaseURL(String baseUrl, String data, String mimeType, String encoding, String historyUrl); public void evaluateJavaScript(String script, ValueCallback<String> resultCallback); public void saveWebArchive(String filename); public void saveWebArchive(String basename, boolean autoname, ValueCallback<String> callback); public void stopLoading(); public void reload(); public boolean canGoBack(); public void goBack(); public boolean canGoForward(); public void goForward(); public boolean canGoBackOrForward(int steps); public void goBackOrForward(int steps); public boolean isPrivateBrowsingEnabled(); public boolean pageUp(boolean top); public boolean pageDown(boolean bottom); public void insertVisualStateCallback(long requestId, VisualStateCallback callback); public void clearView(); public Picture capturePicture(); public PrintDocumentAdapter createPrintDocumentAdapter(String documentName); public float getScale(); public void setInitialScale(int scaleInPercent); public void invokeZoomPicker(); public HitTestResult getHitTestResult(); public void requestFocusNodeHref(Message hrefMsg); public void requestImageRef(Message msg); public String getUrl(); public String getOriginalUrl(); public String getTitle(); public Bitmap getFavicon(); public String getTouchIconUrl(); public int getProgress(); public int getContentHeight(); public int getContentWidth(); public void pauseTimers(); public void resumeTimers(); public void onPause(); public void onResume(); public boolean isPaused(); public void freeMemory(); public void clearCache(boolean includeDiskFiles); public void clearFormData(); public void clearHistory(); public void clearSslPreferences(); public WebBackForwardList copyBackForwardList(); public void setFindListener(WebView.FindListener listener); public void findNext(boolean forward); public int findAll(String find); public void findAllAsync(String find); public boolean showFindDialog(String text, boolean showIme); public void clearMatches(); public void documentHasImages(Message response); public void setWebViewClient(WebViewClient client); public WebViewClient getWebViewClient(); public void setDownloadListener(DownloadListener listener); public void setWebChromeClient(WebChromeClient client); public WebChromeClient getWebChromeClient(); public void setPictureListener(PictureListener listener); public void addJavascriptInterface(Object obj, String interfaceName); public void removeJavascriptInterface(String interfaceName); public WebMessagePort[] createWebMessageChannel(); public void postMessageToMainFrame(WebMessage message, Uri targetOrigin); public WebSettings getSettings(); public void setMapTrackballToArrowKeys(boolean setMap); public void flingScroll(int vx, int vy); public View getZoomControls(); public boolean canZoomIn(); public boolean canZoomOut(); public boolean zoomBy(float zoomFactor); public boolean zoomIn(); public boolean zoomOut(); public void dumpViewHierarchyWithProperties(BufferedWriter out, int level); public View findHierarchyView(String className, int hashCode); public void setRendererPriorityPolicy(int rendererRequestedPriority, boolean waivedWhenNotVisible); public int getRendererRequestedPriority(); public boolean getRendererPriorityWaivedWhenNotVisible(); @SuppressWarnings("unused") public default void setTextClassifier(@Nullable TextClassifier textClassifier) { } @NonNull public default TextClassifier getTextClassifier() { return TextClassifier.NO_OP; } //------------------------------------------------------------------------- // Provider internal methods //------------------------------------------------------------------------- /** * @return the ViewDelegate implementation. This provides the functionality to back all of * the name-sake functions from the View and ViewGroup base classes of WebView. */ /* package */ ViewDelegate getViewDelegate(); /** * @return a ScrollDelegate implementation. Normally this would be same object as is * returned by getViewDelegate(). */ /* package */ ScrollDelegate getScrollDelegate(); /** * Only used by FindActionModeCallback to inform providers that the find dialog has * been dismissed. */ public void notifyFindDialogDismissed(); //------------------------------------------------------------------------- // View / ViewGroup delegation methods //------------------------------------------------------------------------- /** * Provides mechanism for the name-sake methods declared in View and ViewGroup to be delegated * into the WebViewProvider instance. * NOTE: For many of these methods, the WebView will provide a super.Foo() call before or after * making the call into the provider instance. This is done for convenience in the common case * of maintaining backward compatibility. For remaining super class calls (e.g. where the * provider may need to only conditionally make the call based on some internal state) see the * {@link WebView.PrivateAccess} callback class. */ // TODO: See if the pattern of the super-class calls can be rationalized at all, and document // the remainder on the methods below. interface ViewDelegate { public boolean shouldDelayChildPressedState(); public void onProvideVirtualStructure(android.view.ViewStructure structure); default void onProvideAutofillVirtualStructure( @SuppressWarnings("unused") android.view.ViewStructure structure, @SuppressWarnings("unused") int flags) { } default void autofill(@SuppressWarnings("unused") SparseArray<AutofillValue> values) { } default boolean isVisibleToUserForAutofill(@SuppressWarnings("unused") int virtualId) { return true; // true is the default value returned by View.isVisibleToUserForAutofill() } public AccessibilityNodeProvider getAccessibilityNodeProvider(); public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info); public void onInitializeAccessibilityEvent(AccessibilityEvent event); public boolean performAccessibilityAction(int action, Bundle arguments); public void setOverScrollMode(int mode); public void setScrollBarStyle(int style); public void onDrawVerticalScrollBar(Canvas canvas, Drawable scrollBar, int l, int t, int r, int b); public void onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY); public void onWindowVisibilityChanged(int visibility); public void onDraw(Canvas canvas); public void setLayoutParams(LayoutParams layoutParams); public boolean performLongClick(); public void onConfigurationChanged(Configuration newConfig); public InputConnection onCreateInputConnection(EditorInfo outAttrs); public boolean onDragEvent(DragEvent event); public boolean onKeyMultiple(int keyCode, int repeatCount, KeyEvent event); public boolean onKeyDown(int keyCode, KeyEvent event); public boolean onKeyUp(int keyCode, KeyEvent event); public void onAttachedToWindow(); public void onDetachedFromWindow(); public default void onMovedToDisplay(int displayId, Configuration config) { } public void onVisibilityChanged(View changedView, int visibility); public void onWindowFocusChanged(boolean hasWindowFocus); public void onFocusChanged(boolean focused, int direction, Rect previouslyFocusedRect); public boolean setFrame(int left, int top, int right, int bottom); public void onSizeChanged(int w, int h, int ow, int oh); public void onScrollChanged(int l, int t, int oldl, int oldt); public boolean dispatchKeyEvent(KeyEvent event); public boolean onTouchEvent(MotionEvent ev); public boolean onHoverEvent(MotionEvent event); public boolean onGenericMotionEvent(MotionEvent event); public boolean onTrackballEvent(MotionEvent ev); public boolean requestFocus(int direction, Rect previouslyFocusedRect); public void onMeasure(int widthMeasureSpec, int heightMeasureSpec); public boolean requestChildRectangleOnScreen(View child, Rect rect, boolean immediate); public void setBackgroundColor(int color); public void setLayerType(int layerType, Paint paint); public void preDispatchDraw(Canvas canvas); public void onStartTemporaryDetach(); public void onFinishTemporaryDetach(); public void onActivityResult(int requestCode, int resultCode, Intent data); public Handler getHandler(Handler originalHandler); public View findFocus(View originalFocusedView); @SuppressWarnings("unused") default boolean onCheckIsTextEditor() { return false; } } interface ScrollDelegate { // These methods are declared protected in the ViewGroup base class. This interface // exists to promote them to public so they may be called by the WebView proxy class. // TODO: Combine into ViewDelegate? /** * See {@link android.webkit.WebView#computeHorizontalScrollRange} */ public int computeHorizontalScrollRange(); /** * See {@link android.webkit.WebView#computeHorizontalScrollOffset} */ public int computeHorizontalScrollOffset(); /** * See {@link android.webkit.WebView#computeVerticalScrollRange} */ public int computeVerticalScrollRange(); /** * See {@link android.webkit.WebView#computeVerticalScrollOffset} */ public int computeVerticalScrollOffset(); /** * See {@link android.webkit.WebView#computeVerticalScrollExtent} */ public int computeVerticalScrollExtent(); /** * See {@link android.webkit.WebView#computeScroll} */ public void computeScroll(); } }