| /* |
| * 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.car.ui.uxr; |
| |
| import static com.android.car.ui.core.CarUi.MIN_TARGET_API; |
| |
| import android.annotation.TargetApi; |
| import android.view.View; |
| |
| import androidx.annotation.Nullable; |
| |
| import java.util.Arrays; |
| import java.util.function.Function; |
| |
| /** |
| * This is a utility class designed to make it easier to create a new {@link DrawableStateView}. |
| * |
| * To use, subclass a view and forward it's {@link View#onCreateDrawableState(int)} and |
| * {@link DrawableStateView#setExtraDrawableState(int[], int[])} methods to this object. |
| */ |
| @SuppressWarnings("AndroidJdkLibsChecker") |
| @TargetApi(MIN_TARGET_API) |
| class DrawableStateUtil implements DrawableStateView { |
| |
| private final View mView; |
| @Nullable |
| private int[] mStateToAdd; |
| @Nullable |
| private int[] mStateToRemove; |
| |
| DrawableStateUtil(View view) { |
| mView = view; |
| } |
| |
| /** |
| * Forward the View's onCreateDrawableState to this method. |
| * |
| * @param extraSpace The extraSpace parameter passed to the View's onCreateDrawableState |
| * @param callSuper A reference to the View's super.onCreateDrawableState() |
| * @return The intended result of the View's onCreateDrawableState() |
| */ |
| public int[] onCreateDrawableState(int extraSpace, Function<Integer, int[]> callSuper) { |
| int[] result; |
| if (mStateToAdd == null) { |
| result = callSuper.apply(extraSpace); |
| } else { |
| result = mergeDrawableStates( |
| callSuper.apply(extraSpace + mStateToAdd.length), mStateToAdd); |
| } |
| |
| if (mStateToRemove != null && mStateToRemove.length != 0) { |
| result = Arrays.stream(result) |
| .filter(state -> Arrays.stream(mStateToRemove).noneMatch( |
| toRemove -> state == toRemove)) |
| .toArray(); |
| } |
| |
| return result; |
| } |
| |
| /** |
| * Forward your View's setExtraDrawableState here. |
| */ |
| @Override |
| public void setExtraDrawableState(@Nullable int[] stateToAdd, @Nullable int[] stateToRemove) { |
| mStateToAdd = stateToAdd; |
| mStateToRemove = stateToRemove; |
| mView.refreshDrawableState(); |
| } |
| |
| /** Copied from {@link View} */ |
| private static int[] mergeDrawableStates(int[] baseState, int[] additionalState) { |
| int i = baseState.length - 1; |
| while (i >= 0 && baseState[i] == 0) { |
| i--; |
| } |
| System.arraycopy(additionalState, 0, baseState, i + 1, additionalState.length); |
| return baseState; |
| } |
| } |