core/java/com/android/internal/policy/ScreenDecorationsUtils.java

/*
 * Copyright (C) 2018 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.internal.policy;

import android.content.Context;
import android.content.res.Resources;
import android.view.RoundedCorners;

import com.android.internal.R;

/**
 * Utility functions for screen decorations used by both window manager and System UI.
 */
public class ScreenDecorationsUtils {

    /**
     * Corner radius that should be used on windows in order to cover the display.
     * These values are expressed in pixels because they should not respect display or font
     * scaling, this means that we don't have to reload them on config changes.
     *
     * Note that if the context is not an UI context(not associated with Display), it will use
     * default display.
     */
    public static float getWindowCornerRadius(Context context) {
        final Resources resources = context.getResources();
        if (!supportsRoundedCornersOnWindows(resources)) {
            return 0f;
        }
        // Use Context#getDisplayNoVerify() in case the context is not an UI context.
        final String displayUniqueId = context.getDisplayNoVerify().getUniqueId();
        // Radius that should be used in case top or bottom aren't defined.
        float defaultRadius = RoundedCorners.getRoundedCornerRadius(resources, displayUniqueId)
                - RoundedCorners.getRoundedCornerRadiusAdjustment(resources, displayUniqueId);

        float topRadius = RoundedCorners.getRoundedCornerTopRadius(resources, displayUniqueId)
                - RoundedCorners.getRoundedCornerRadiusTopAdjustment(resources, displayUniqueId);
        if (topRadius == 0f) {
            topRadius = defaultRadius;
        }
        float bottomRadius = RoundedCorners.getRoundedCornerBottomRadius(resources, displayUniqueId)
                - RoundedCorners.getRoundedCornerRadiusBottomAdjustment(resources, displayUniqueId);
        if (bottomRadius == 0f) {
            bottomRadius = defaultRadius;
        }

        // Always use the smallest radius to make sure the rounded corners will
        // completely cover the display.
        return Math.min(topRadius, bottomRadius);
    }

    /**
     * If live rounded corners are supported on windows.
     */
    public static boolean supportsRoundedCornersOnWindows(Resources resources) {
        return resources.getBoolean(R.bool.config_supportsRoundedCornersOnWindows);
    }
}