Move WindowContext module to window package

In this way, we can clarify the owners and it is easier to maintain.
Also refactor to move WindowContext creation logic to ContextImpl.

Test: atest WindowContext WindowContextTests WindowContextPolicyTests
Bug: 159767464
Bug: 152193787

Change-Id: I78432aa18aa97e001f5a9a04321109e456fd137b

1 files changed, 103 insertions, 0 deletions

diff --git a/core/java/android/window/WindowTokenClient.java b/core/java/android/window/WindowTokenClient.java
new file mode 100644
index 000000000000..b2fe4d9573f1
--- /dev/null
+++ b/core/java/android/window/WindowTokenClient.java
@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2020 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.window;
+
+import android.annotation.NonNull;
+import android.app.ActivityThread;
+import android.app.IWindowToken;
+import android.app.ResourcesManager;
+import android.content.Context;
+import android.content.res.Configuration;
+import android.os.Bundle;
+import android.os.IBinder;
+import android.view.WindowManagerGlobal;
+
+import java.lang.ref.WeakReference;
+
+/**
+ * This class is used to receive {@link Configuration} changes from the associated window manager
+ * node on the server side, and apply the change to the {@link Context#getResources() associated
+ * Resources} of the attached {@link Context}. It is also used as
+ * {@link Context#getWindowContextToken() the token of non-Activity UI Contexts}.
+ *
+ * @see WindowContext
+ * @see android.view.IWindowManager#registerWindowContextListener(IBinder, int, int, Bundle)
+ *
+ * @hide
+ */
+public class WindowTokenClient extends IWindowToken.Stub {
+    /**
+     * Attached {@link Context} for this window token to update configuration and resources.
+     * Initialized by {@link #attachContext(Context)}.
+     */
+    private WeakReference<Context> mContextRef = null;
+
+    private final ResourcesManager mResourcesManager = ResourcesManager.getInstance();
+
+    /**
+     * Attaches {@code context} to this {@link WindowTokenClient}. Each {@link WindowTokenClient}
+     * can only attach one {@link Context}.
+     * <p>This method must be called before invoking
+     * {@link android.view.IWindowManager#registerWindowContextListener(IBinder, int, int,
+     * Bundle, boolean)}.<p/>
+     *
+     * @param context context to be attached
+     * @throws IllegalStateException if attached context has already existed.
+     */
+    public void attachContext(@NonNull Context context) {
+        if (mContextRef != null) {
+            throw new IllegalStateException("Context is already attached.");
+        }
+        mContextRef = new WeakReference<>(context);
+    }
+
+    @Override
+    public void onConfigurationChanged(Configuration newConfig, int newDisplayId) {
+        final Context context = mContextRef.get();
+        if (context == null) {
+            return;
+        }
+        final int currentDisplayId = context.getDisplayId();
+        final boolean displayChanged = newDisplayId != currentDisplayId;
+        final Configuration config = context.getResources().getConfiguration();
+        final boolean configChanged = config.diff(newConfig) != 0;
+        if (displayChanged || configChanged) {
+            // TODO(ag/9789103): update resource manager logic to track non-activity tokens
+            mResourcesManager.updateResourcesForActivity(this, newConfig, newDisplayId);
+            if (context instanceof WindowContext) {
+                ActivityThread.currentActivityThread().getHandler().post(
+                        () -> ((WindowContext) context).dispatchConfigurationChanged(newConfig));
+            }
+        }
+        if (displayChanged) {
+            context.updateDisplay(newDisplayId);
+        }
+    }
+
+    @Override
+    public void onWindowTokenRemoved() {
+        final Context context = mContextRef.get();
+        if (context != null) {
+            context.destroy();
+            mContextRef.clear();
+        }
+        ActivityThread.currentActivityThread().getHandler().post(() -> {
+            // If the tracked window token is detached, release all views attached to this token.
+            WindowManagerGlobal.getInstance().closeAll(WindowTokenClient.this,
+                    "#onWindowTokenRemoved()", "WindowTokenClient");
+        });
+    }
+}