content: /*
   * Copyright 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 android.graphics.drawable;
  
  import android.annotation.IntRange;
  import android.annotation.NonNull;
  import android.annotation.Nullable;
  import android.content.pm.ActivityInfo;
  import android.content.res.ColorStateList;
  import android.content.res.Resources;
  import android.graphics.BlendMode;
  import android.graphics.Canvas;
  import android.graphics.ColorFilter;
  import android.graphics.PixelFormat;
  import android.graphics.Rect;
  import android.util.MathUtils;
  
  /**
   * A Drawable that manages a {@link ColorDrawable} to make it stateful and backed by a
   * {@link ColorStateList}.
   */
  public class ColorStateListDrawable extends Drawable implements Drawable.Callback {
      private ColorDrawable mColorDrawable;
      private ColorStateListDrawableState mState;
      private boolean mMutated = false;
  
      public ColorStateListDrawable() {
          mState = new ColorStateListDrawableState();
          initializeColorDrawable();
      }
  
      public ColorStateListDrawable(@NonNull ColorStateList colorStateList) {
          mState = new ColorStateListDrawableState();
          initializeColorDrawable();
          setColorStateList(colorStateList);
      }
  
      @Override
      public void draw(@NonNull Canvas canvas) {
          mColorDrawable.draw(canvas);
      }
  
      @Override
      @IntRange(from = 0, to = 255)
      public int getAlpha() {
          return mColorDrawable.getAlpha();
      }
  
      @Override
      public boolean isStateful() {
          return mState.isStateful();
      }
  
      @Override
      public boolean hasFocusStateSpecified() {
          return mState.hasFocusStateSpecified();
      }
  
      @Override
      public @NonNull Drawable getCurrent() {
          return mColorDrawable;
      }
  
      @Override
      public void applyTheme(@NonNull Resources.Theme t) {
          super.applyTheme(t);
  
          if (mState.mColor != null) {
              setColorStateList(mState.mColor.obtainForTheme(t));
          }
  
          if (mState.mTint != null) {
              setTintList(mState.mTint.obtainForTheme(t));
          }
      }
  
      @Override
      public boolean canApplyTheme() {
          return super.canApplyTheme() || mState.canApplyTheme();
      }
  
      @Override
      public void setAlpha(@IntRange(from = 0, to = 255) int alpha) {
          mState.mAlpha = alpha;
          onStateChange(getState());
      }
  
      /**
       * Remove the alpha override, reverting to the alpha defined on each color in the
       * {@link ColorStateList}.
       */
      public void clearAlpha() {
          mState.mAlpha = -1;
          onStateChange(getState());
      }
  
      @Override
      public void setTintList(@Nullable ColorStateList tint) {
          mState.mTint = tint;
          mColorDrawable.setTintList(tint);
          onStateChange(getState());
      }
  
      @Override
      public void setTintBlendMode(@NonNull BlendMode blendMode) {
          mState.mBlendMode = blendMode;
          mColorDrawable.setTintBlendMode(blendMode);
          onStateChange(getState());
      }
  
      @Override
      public @Nullable ColorFilter getColorFilter() {
          return mColorDrawable.getColorFilter();
      }
  
      @Override
      public void setColorFilter(@Nullable ColorFilter colorFilter) {
          mColorDrawable.setColorFilter(colorFilter);
      }
  
      @Override
      public @PixelFormat.Opacity int getOpacity() {
          return mColorDrawable.getOpacity();
      }
  
      @Override
      protected void onBoundsChange(Rect bounds) {
          super.onBoundsChange(bounds);
          mColorDrawable.setBounds(bounds);
      }
  
      @Override
      protected boolean onStateChange(int[] state) {
          if (mState.mColor != null) {
              int color = mState.mColor.getColorForState(state, mState.mColor.getDefaultColor());
  
              if (mState.mAlpha != -1) {
                  color = (color & 0xFFFFFF) | MathUtils.constrain(mState.mAlpha, 0, 255) << 24;
              }
  
              if (color != mColorDrawable.getColor()) {
                  mColorDrawable.setColor(color);
                  mColorDrawable.setState(state);
                  return true;
              } else {
                  return mColorDrawable.setState(state);
              }
          } else {
              return false;
          }
      }
  
      @Override
      public void invalidateDrawable(@NonNull Drawable who) {
          if (who == mColorDrawable && getCallback() != null) {
              getCallback().invalidateDrawable(this);
          }
      }
  
      @Override
      public void scheduleDrawable(@NonNull Drawable who, @NonNull Runnable what, long when) {
          if (who == mColorDrawable && getCallback() != null) {
              getCallback().scheduleDrawable(this, what, when);
          }
      }
  
      @Override
      public void unscheduleDrawable(@NonNull Drawable who, @NonNull Runnable what) {
          if (who == mColorDrawable && getCallback() != null) {
              getCallback().unscheduleDrawable(this, what);
          }
      }
  
      @Override
      public @NonNull ConstantState getConstantState() {
          mState.mChangingConfigurations = mState.mChangingConfigurations
                  | (getChangingConfigurations() & ~mState.getChangingConfigurations());
          return mState;
      }
  
      /**
       * Returns the ColorStateList backing this Drawable, or a new ColorStateList of the default
       * ColorDrawable color if one hasn't been defined yet.
       *
       * @return a ColorStateList
       */
      public @NonNull ColorStateList getColorStateList() {
          if (mState.mColor == null) {
              return ColorStateList.valueOf(mColorDrawable.getColor());
          } else {
              return mState.mColor;
          }
      }
  
      @Override
      public int getChangingConfigurations() {
          return super.getChangingConfigurations() | mState.getChangingConfigurations();
      }
  
      @Override
      public @NonNull Drawable mutate() {
          if (!mMutated && super.mutate() == this) {
              mState = new ColorStateListDrawableState(mState);
              mMutated = true;
          }
          return this;
      }
  
      /**
       * @hide
       */
      @Override
      public void clearMutated() {
          super.clearMutated();
          mMutated = false;
      }
  
      /**
       * Replace this Drawable's ColorStateList. It is not copied, so changes will propagate on the
       * next call to {@link #setState(int[])}.
       *
       * @param colorStateList A color state list to attach.
       */
      public void setColorStateList(@NonNull ColorStateList colorStateList) {
          mState.mColor = colorStateList;
          onStateChange(getState());
      }
  
      static final class ColorStateListDrawableState extends ConstantState {
          ColorStateList mColor = null;
          ColorStateList mTint = null;
          int mAlpha = -1;
          BlendMode mBlendMode = DEFAULT_BLEND_MODE;
          @ActivityInfo.Config int mChangingConfigurations = 0;
  
          ColorStateListDrawableState() {
          }
  
          ColorStateListDrawableState(ColorStateListDrawableState state) {
              mColor = state.mColor;
              mTint = state.mTint;
              mAlpha = state.mAlpha;
              mBlendMode = state.mBlendMode;
              mChangingConfigurations = state.mChangingConfigurations;
          }
  
          @Override
          public Drawable newDrawable() {
              return new ColorStateListDrawable(this);
          }
  
          @Override
          public @ActivityInfo.Config int getChangingConfigurations() {
              return mChangingConfigurations
                      | (mColor != null ? mColor.getChangingConfigurations() : 0)
                      | (mTint != null ? mTint.getChangingConfigurations() : 0);
          }
  
          public boolean isStateful() {
              return (mColor != null && mColor.isStateful())
                      || (mTint != null && mTint.isStateful());
          }
  
          public boolean hasFocusStateSpecified() {
              return (mColor != null && mColor.hasFocusStateSpecified())
                      || (mTint != null && mTint.hasFocusStateSpecified());
          }
  
          @Override
          public boolean canApplyTheme() {
              return (mColor != null && mColor.canApplyTheme())
                      || (mTint != null && mTint.canApplyTheme());
          }
      }
  
      private ColorStateListDrawable(@NonNull ColorStateListDrawableState state) {
          mState = state;
          initializeColorDrawable();
      }
  
      private void initializeColorDrawable() {
          mColorDrawable = new ColorDrawable();
          mColorDrawable.setCallback(this);
  
          if (mState.mTint != null) {
              mColorDrawable.setTintList(mState.mTint);
          }
  
          if (mState.mBlendMode != DEFAULT_BLEND_MODE) {
              mColorDrawable.setTintBlendMode(mState.mBlendMode);
          }
      }
  }
  