diff --git a/src/com/android/launcher3/widget/picker/WidgetsListLayoutManager.java b/src/com/android/launcher3/widget/picker/WidgetsListLayoutManager.java new file mode 100644 index 0000000000..2b7f544c56 --- /dev/null +++ b/src/com/android/launcher3/widget/picker/WidgetsListLayoutManager.java @@ -0,0 +1,51 @@ +/* + * Copyright (C) 2021 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 com.android.launcher3.widget.picker; + +import android.content.Context; + +import androidx.annotation.Nullable; +import androidx.recyclerview.widget.LinearLayoutManager; +import androidx.recyclerview.widget.RecyclerView; + +import com.android.launcher3.widget.picker.SearchAndRecommendationsScrollController.OnContentChangeListener; + +/** + * A layout manager for the {@link WidgetsRecyclerView}. + * + * {@link #setOnContentChangeListener(OnContentChangeListener)} can be used to register a callback + * for when the content of the layout manager has changed, following measurement and animation. + */ +public final class WidgetsListLayoutManager extends LinearLayoutManager { + @Nullable + private OnContentChangeListener mOnContentChangeListener; + + public WidgetsListLayoutManager(Context context) { + super(context); + } + + @Override + public void onLayoutCompleted(RecyclerView.State state) { + super.onLayoutCompleted(state); + if (mOnContentChangeListener != null) { + mOnContentChangeListener.onContentChanged(); + } + } + + public void setOnContentChangeListener(@Nullable OnContentChangeListener listener) { + mOnContentChangeListener = listener; + } +} diff --git a/src/com/android/launcher3/widget/picker/WidgetsRecyclerView.java b/src/com/android/launcher3/widget/picker/WidgetsRecyclerView.java index 4f4f1a3566..3ee8b33b53 100644 --- a/src/com/android/launcher3/widget/picker/WidgetsRecyclerView.java +++ b/src/com/android/launcher3/widget/picker/WidgetsRecyclerView.java @@ -23,7 +23,6 @@ import android.view.MotionEvent; import android.view.View; import android.widget.TableLayout; -import androidx.annotation.NonNull; import androidx.annotation.Nullable; import androidx.recyclerview.widget.LinearLayoutManager; import androidx.recyclerview.widget.RecyclerView; @@ -83,7 +82,9 @@ public class WidgetsRecyclerView extends BaseRecyclerView implements OnItemTouch super.onFinishInflate(); // create a layout manager with Launcher's context so that scroll position // can be preserved during screen rotation. - setLayoutManager(new LinearLayoutManager(getContext())); + WidgetsListLayoutManager layoutManager = new WidgetsListLayoutManager(getContext()); + layoutManager.setOnContentChangeListener(mOnContentChangeListener); + setLayoutManager(layoutManager); } @Override @@ -92,22 +93,6 @@ public class WidgetsRecyclerView extends BaseRecyclerView implements OnItemTouch mAdapter = (WidgetsListAdapter) adapter; } - @Override - public void onChildAttachedToWindow(@NonNull View child) { - super.onChildAttachedToWindow(child); - if (mOnContentChangeListener != null) { - mOnContentChangeListener.onContentChanged(); - } - } - - @Override - public void onChildDetachedFromWindow(@NonNull View child) { - super.onChildDetachedFromWindow(child); - if (mOnContentChangeListener != null) { - mOnContentChangeListener.onContentChanged(); - } - } - /** * Maps the touch (from 0..1) to the adapter position that should be visible. */ @@ -268,6 +253,10 @@ public class WidgetsRecyclerView extends BaseRecyclerView implements OnItemTouch public void setOnContentChangeListener(@Nullable OnContentChangeListener listener) { mOnContentChangeListener = listener; + WidgetsListLayoutManager layoutManager = (WidgetsListLayoutManager) getLayoutManager(); + if (layoutManager != null) { + layoutManager.setOnContentChangeListener(listener); + } } /**