material-components_material-components-android/lib/java/com/google/android/material/imageview/ShapeableImageView.java

/*
 * Copyright (C) 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
 *
 *       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.google.android.material.imageview;

import com.google.android.material.R;

import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.ColorStateList;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Matrix.ScaleToFit;
import android.graphics.Outline;
import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.graphics.Path;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.Shader;
import android.graphics.drawable.BitmapDrawable;
import android.os.Build.VERSION;
import android.os.Build.VERSION_CODES;
import androidx.annotation.ColorRes;
import androidx.annotation.DimenRes;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.annotation.Px;
import androidx.appcompat.content.res.AppCompatResources;
import androidx.appcompat.widget.AppCompatImageView;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
import android.view.ViewOutlineProvider;
import com.google.android.material.resources.MaterialResources;
import com.google.android.material.shape.ShapeAppearanceModel;
import com.google.android.material.shape.ShapeAppearancePathProvider;
import com.google.android.material.shape.Shapeable;

/**
 * An ImageView that draws the bitmap with the provided Shape.
 */
@ExperimentalImageView
public class ShapeableImageView extends AppCompatImageView implements Shapeable {

  private static final int DEF_STYLE_RES = R.style.Widget_MaterialComponents_ShapeableImageView;

  private static final String TAG = "ShapeableImageView";

  private final ShapeAppearancePathProvider pathProvider = new ShapeAppearancePathProvider();
  private final Matrix matrix;
  private final RectF source;
  private final RectF destination;
  private final Paint bitmapPaint;
  private final Paint borderPaint;
  private final Path path = new Path();

  private ColorStateList strokeColor;
  private ShapeAppearanceModel shapeAppearanceModel;
  @Px
  private int strokeWidth;

  public ShapeableImageView(Context context) {
    this(context, null, 0);
  }

  public ShapeableImageView(Context context, @Nullable AttributeSet attrs) {
    this(context, attrs, 0);
  }

  public ShapeableImageView(Context context, @Nullable AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    matrix = new Matrix();
    source = new RectF();
    destination = new RectF();
    bitmapPaint = new Paint();
    bitmapPaint.setAntiAlias(true);
    bitmapPaint.setFilterBitmap(true);
    bitmapPaint.setDither(true);

    TypedArray attributes = context.obtainStyledAttributes(
        attrs,
        R.styleable.ShapeableImageView,
        defStyle,
        DEF_STYLE_RES);

    strokeColor =
        MaterialResources.getColorStateList(
            context, attributes, R.styleable.ShapeableImageView_strokeColor);

    strokeWidth = attributes.getDimensionPixelSize(R.styleable.ShapeableImageView_strokeWidth, 0);

    borderPaint = new Paint();
    borderPaint.setStyle(Style.STROKE);
    borderPaint.setAntiAlias(true);
    shapeAppearanceModel =
        ShapeAppearanceModel.builder(context, attrs, defStyle, DEF_STYLE_RES).build();
    if (VERSION.SDK_INT >= VERSION_CODES.LOLLIPOP) {
      setOutlineProvider(new OutlineProvider());
    }
  }

  @Override
  protected void onDraw(Canvas canvas) {
    // only supporting BitmapDrawable for now.
    if (!(getDrawable() instanceof BitmapDrawable)) {
      Log.e(TAG, "Shapeable Image view does not support the provided drawable. "
          + "Only BitmapDrawble is supported");
      return;
    }

    BitmapDrawable bitmapDrawable = (BitmapDrawable) getDrawable();
    Bitmap bitmap = bitmapDrawable.getBitmap();
    if (bitmap == null) {
      Log.e(TAG, "Bitmap from drawable was null");
      return;
    }

    source.set(0, 0, bitmap.getWidth(), bitmap.getHeight());
    drawBitmap(bitmap, canvas, source, destination);
  }

  @Override
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    destination.set(
        getPaddingLeft(),
        getPaddingTop(),
        getMeasuredWidth() - getPaddingRight(),
        getMeasuredHeight() - getPaddingBottom());
    pathProvider.calculatePath(shapeAppearanceModel, 1f /*interpolation*/, destination, path);
  }

  private void drawBitmap(
      Bitmap bitmap,
      Canvas canvas,
      RectF source,
      RectF dest) {
    // Draw bitmap through shader first.
    BitmapShader shader = new BitmapShader(
        bitmap,
        Shader.TileMode.CLAMP,
        Shader.TileMode.CLAMP);
    matrix.reset();

    // Fit bitmap to bounds.
    matrix.setRectToRect(source, dest, ScaleToFit.FILL);

    shader.setLocalMatrix(matrix);
    bitmapPaint.setShader(shader);

    canvas.drawPath(path, bitmapPaint);
    borderPaint.setStrokeWidth(strokeWidth);
    int colorForState = strokeColor
        .getColorForState(getDrawableState(), strokeColor.getDefaultColor());

    if (strokeWidth > 0 && colorForState != Color.TRANSPARENT) {
      borderPaint.setColor(colorForState);
      canvas.drawPath(path, borderPaint);
    }
  }

  @Override
  public void setShapeAppearanceModel(@NonNull ShapeAppearanceModel shapeAppearanceModel) {
    this.shapeAppearanceModel = shapeAppearanceModel;
    requestLayout();
  }

  @NonNull
  @Override
  public ShapeAppearanceModel getShapeAppearanceModel() {
    return shapeAppearanceModel;
  }

  /**
   * Sets the stroke color resource for this ImageView. Both stroke color and stroke width must be
   * set for a stroke to be drawn.
   *
   * @param strokeColorResourceId Color resource to use for the stroke.
   * @attr ref com.google.android.libraries.material.imageview.R.styleable#ShapeableImageView_strokeColor
   * @see #setStrokeColor(ColorStateList)
   * @see #getStrokeColor()
   */
  public void setStrokeColorResource(@ColorRes int strokeColorResourceId) {
    setStrokeColor(AppCompatResources.getColorStateList(getContext(), strokeColorResourceId));
  }

  /**
   * Returns the stroke color for this ImageView.
   *
   * @attr ref com.google.android.libraries.material.imageview.R.styleable#ShapeableImageView_strokeColor
   * @see #setStrokeColor(ColorStateList)
   * @see #setStrokeColorResource(int)
   */
  @Nullable
  public ColorStateList getStrokeColor() {
    return strokeColor;
  }

  /**
   * Sets the stroke width for this ImageView. Both stroke color and stroke width must be set for a
   * stroke to be drawn.
   *
   * @param strokeWidth Stroke width for this ImageView.
   * @attr ref com.google.android.libraries.material.imageview.R.styleable#ShapeableImageView_strokeWidth
   * @see #setStrokeWidthResource(int)
   * @see #getStrokeWidth()
   */
  public void setStrokeWidth(@Px int strokeWidth) {
    if (this.strokeWidth != strokeWidth) {
      this.strokeWidth = strokeWidth;
      invalidate();
    }
  }

  /**
   * Sets the stroke width dimension resource for this ImageView. Both stroke color and stroke width
   * must be set for a stroke to be drawn.
   *
   * @param strokeWidthResourceId Stroke width dimension resource for this ImageView.
   * @attr ref com.google.android.libraries.material.imageview.R.styleable#ShapeableImageView_strokeWidth
   * @see #setStrokeWidth(int)
   * @see #getStrokeWidth()
   */
  public void setStrokeWidthResource(@DimenRes int strokeWidthResourceId) {
    setStrokeWidth(getResources().getDimensionPixelSize(strokeWidthResourceId));
  }

  /**
   * Gets the stroke width for this ImageView.
   *
   * @return Stroke width for this ImageView.
   * @attr ref com.google.android.libraries.material.imageview.R.styleable#ShapeableImageView_strokeWidth
   * @see #setStrokeWidth(int)
   * @see #setStrokeWidthResource(int)
   */
  @Px
  public int getStrokeWidth() {
    return strokeWidth;
  }

  public void setStrokeColor(@Nullable ColorStateList strokeColor) {
    this.strokeColor = strokeColor;
    invalidate();
  }

  @TargetApi(VERSION_CODES.LOLLIPOP)
  class OutlineProvider extends ViewOutlineProvider {

    private Rect rect = new Rect();

    @Override
    public void getOutline(View view, Outline outline) {
      if (shapeAppearanceModel != null && shapeAppearanceModel.isRoundRect(destination)) {
        destination.round(rect);
        float cornerSize =
            shapeAppearanceModel.getBottomLeftCornerSize().getCornerSize(destination);
        outline.setRoundRect(rect, cornerSize);
      }
    }
  }
}