/*
 * Copyright 2019 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
 *
 *     https://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.google.android.material.ripple;

import android.graphics.Canvas;
import androidx.annotation.RestrictTo;
import androidx.annotation.RestrictTo.Scope;
import com.google.android.material.shape.MaterialShapeDrawable;
import com.google.android.material.shape.ShapeAppearanceModel;

/**
 * A compat {@link android.graphics.drawable.Drawable} to be used pre-Lollipop for drawing an
 * overlay on top of a background for pressed, focused, and hovered states.
 *
 * <p>This Drawable is a {@link MaterialShapeDrawable} so that it can be shaped to match a
 * MaterialShapeDrawable background.
 *
 * <p>Unlike the framework {@link android.graphics.drawable.RippleDrawable}, this will <b>not</b>
 * apply different alphas for pressed, focused, and hovered states and it does not provide a ripple
 * animation for the pressed state.
 */
@RestrictTo(Scope.LIBRARY_GROUP)
public class RippleDrawableCompat extends MaterialShapeDrawable {

  /**
   * Whether this compat ripple should be drawn. True when enabled and (pressed, focused, or
   * enabled).
   */
  private boolean shouldDrawRipple = false;

  /**
   * Creates a {@link RippleDrawableCompat} with the given shape.
   *
   * @param shapeAppearanceModel the {@link ShapeAppearanceModel} containing the path that will be
   *     rendered in this drawable.
   */
  public RippleDrawableCompat(ShapeAppearanceModel shapeAppearanceModel) {
    super(shapeAppearanceModel);
  }

  @Override
  public void draw(Canvas canvas) {
    if (shouldDrawRipple) {
      super.draw(canvas);
    }
  }

  @Override
  protected boolean onStateChange(int[] stateSet) {
    final boolean changed = super.onStateChange(stateSet);
    boolean enabled = false;
    boolean pressed = false;
    boolean focused = false;
    boolean hovered = false;

    for (int state : stateSet) {
      if (state == android.R.attr.state_enabled) {
        enabled = true;
      } else if (state == android.R.attr.state_focused) {
        focused = true;
      } else if (state == android.R.attr.state_pressed) {
        pressed = true;
      } else if (state == android.R.attr.state_hovered) {
        hovered = true;
      }
    }
    shouldDrawRipple = enabled && (pressed || focused || hovered);
    return changed;
  }
}

Create compat ripples that are based on MaterialShapeDrawable and only draw when enabled and in the pressed, focused, or hovered states.
Create compat ripples that are based on MaterialShapeDrawable and only draw when enabled and in the pressed, focused, or hovered states.

PiperOrigin-RevId: 253783048
