| // Copyright 2015 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.chrome.browser; |
| |
| import android.app.Activity; |
| import android.os.Build; |
| import android.view.View; |
| |
| import org.chromium.chrome.browser.tabmodel.EmptyTabModelSelectorObserver; |
| import org.chromium.chrome.browser.tabmodel.TabModelSelector; |
| import org.chromium.chrome.browser.tabmodel.TabModelSelectorObserver; |
| |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| |
| /** |
| * Handler for tracking and updating the assist status for a given activity. |
| */ |
| public class AssistStatusHandler { |
| private final Activity mActivity; |
| private final TabModelSelectorObserver mSelectorObserver; |
| |
| private Boolean mAssistSupported; |
| private TabModelSelector mTabModelSelector; |
| private Method mSetAssistBlockedMethod; |
| |
| /** |
| * Builds an assist status handler for the specified activity. |
| * @param activity The activity whose assist status should be updated. |
| */ |
| public AssistStatusHandler(Activity activity) { |
| mActivity = activity; |
| |
| mSelectorObserver = new EmptyTabModelSelectorObserver() { |
| @Override |
| public void onChange() { |
| updateAssistState(); |
| } |
| }; |
| } |
| |
| /** |
| * Set the selector that the assist handler should track for tab updates. |
| * @param selector The selector broadcasting tab updates for the activity associated with |
| * this handler. |
| */ |
| public void setTabModelSelector(TabModelSelector selector) { |
| if (mTabModelSelector != null) { |
| mTabModelSelector.removeObserver(mSelectorObserver); |
| } |
| |
| mTabModelSelector = selector; |
| if (mTabModelSelector != null) { |
| mTabModelSelector.addObserver(mSelectorObserver); |
| } |
| |
| updateAssistState(); |
| } |
| |
| /** |
| * Destroy the handler and removes any remaining dependencies. |
| */ |
| public void destroy() { |
| if (mTabModelSelector != null) { |
| mTabModelSelector.removeObserver(mSelectorObserver); |
| mTabModelSelector = null; |
| } |
| } |
| |
| /** |
| * @return Whether assist is currently supported based on the Activity state. |
| */ |
| public boolean isAssistSupported() { |
| return mTabModelSelector == null || !mTabModelSelector.isIncognitoSelected(); |
| } |
| |
| /** |
| * Trigger an update of the assist state. |
| */ |
| public final void updateAssistState() { |
| if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) return; |
| |
| boolean isAssistSupported = isAssistSupported(); |
| if (mAssistSupported == null || mAssistSupported != isAssistSupported) { |
| if (mSetAssistBlockedMethod == null) { |
| try { |
| mSetAssistBlockedMethod = |
| View.class.getMethod("setAssistBlocked", boolean.class); |
| } catch (NoSuchMethodException e) { |
| return; |
| } |
| } |
| View rootContent = mActivity.findViewById(android.R.id.content); |
| try { |
| mSetAssistBlockedMethod.invoke(rootContent, !isAssistSupported); |
| } catch (IllegalAccessException | IllegalArgumentException |
| | InvocationTargetException e) { |
| return; |
| } |
| } |
| mAssistSupported = isAssistSupported; |
| } |
| } |