1 /* 2 * Copyright 2019 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 22 /** 23 * Used to receive callbacks on {@link WebView} renderer events. 24 * 25 * WebViewRenderProcessClient instances may be set or retrieved via {@link 26 * WebView#setWebViewRenderProcessClient(WebViewRenderProcessClient)} and {@link 27 * WebView#getWebViewRenderProcessClient()}. 28 * 29 * Instances may be attached to multiple WebViews, and thus a single renderer event may cause 30 * a callback to be called multiple times with different WebView parameters. 31 */ 32 public abstract class WebViewRenderProcessClient { 33 /** 34 * Called when the renderer currently associated with {@code view} becomes unresponsive as a 35 * result of a long running blocking task such as the execution of JavaScript. 36 * 37 * <p>If a WebView fails to process an input event, or successfully navigate to a new URL within 38 * a reasonable time frame, the renderer is considered to be unresponsive, and this callback 39 * will be called. 40 * 41 * <p>This callback will continue to be called at regular intervals as long as the renderer 42 * remains unresponsive. If the renderer becomes responsive again, {@link 43 * WebViewRenderProcessClient#onRenderProcessResponsive} will be called once, and this method 44 * will not subsequently be called unless another period of unresponsiveness is detected. 45 * 46 * <p>The minimum interval between successive calls to {@code onRenderProcessUnresponsive} is 5 47 * seconds. 48 * 49 * <p>No action is taken by WebView as a result of this method call. Applications may 50 * choose to terminate the associated renderer via the object that is passed to this callback, 51 * if in multiprocess mode, however this must be accompanied by correctly handling 52 * {@link WebViewClient#onRenderProcessGone} for this WebView, and all other WebViews associated 53 * with the same renderer. Failure to do so will result in application termination. 54 * 55 * @param view The {@link WebView} for which unresponsiveness was detected. 56 * @param renderer The {@link WebViewRenderProcess} that has become unresponsive, 57 * or {@code null} if WebView is running in single process mode. 58 */ 59 public abstract void onRenderProcessUnresponsive( 60 @NonNull WebView view, @Nullable WebViewRenderProcess renderer); 61 62 /** 63 * Called once when an unresponsive renderer currently associated with {@code view} becomes 64 * responsive. 65 * 66 * <p>After a WebView renderer becomes unresponsive, which is notified to the application by 67 * {@link WebViewRenderProcessClient#onRenderProcessUnresponsive}, it is possible for the 68 * blocking renderer task to complete, returning the renderer to a responsive state. In that 69 * case, this method is called once to indicate responsiveness. 70 * 71 * <p>No action is taken by WebView as a result of this method call. 72 * 73 * @param view The {@link WebView} for which responsiveness was detected. 74 * 75 * @param renderer The {@link WebViewRenderProcess} that has become responsive, or {@code null} 76 * if WebView is running in single process mode. 77 */ 78 public abstract void onRenderProcessResponsive( 79 @NonNull WebView view, @Nullable WebViewRenderProcess renderer); 80 } 81
