DraweeView.java

/*
 * Copyright (c) 2015-present, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 */

package com.facebook.drawee.view;

import javax.annotation.Nullable;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.ImageView;

import com.facebook.common.internal.Objects;
import com.facebook.drawee.interfaces.DraweeHierarchy;
import com.facebook.drawee.interfaces.DraweeController;

/**
 * View that displays a {@link DraweeHierarchy}.
 *
 * <p> Hierarchy should be set prior to using this view. See {@code setHierarchy}. Because creating
 * a hierarchy is an expensive operation, it is recommended this be done once per view, typically
 * near creation time.
 *
 * <p> In order to display an image, controller has to be set. See {@code setController}.

 * <p> Although ImageView is subclassed instead of subclassing View directly, this class does not
 * support ImageView's setImageXxx, setScaleType and similar methods. Extending ImageView is a short
 * term solution in order to inherit some of its implementation (padding calculations, etc.).
 * This class is likely to be converted to extend View directly in the future, so avoid using
 * ImageView's methods and properties (T5856175).
 */
public class DraweeView<DH extends DraweeHierarchy> extends ImageView {

  private DraweeHolder<DH> mDraweeHolder;

  public DraweeView(Context context) {
    super(context);
    init(context);
  }

  public DraweeView(Context context, AttributeSet attrs) {
    super(context, attrs);
    init(context);
  }

  public DraweeView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    init(context);
  }

  private void init(Context context) {
    mDraweeHolder = DraweeHolder.create(null, context);
  }

  /** Sets the hierarchy. */
  public void setHierarchy(DH hierarchy) {
    mDraweeHolder.setHierarchy(hierarchy);
    super.setImageDrawable(mDraweeHolder.getTopLevelDrawable());
  }

  /** Gets the hierarchy if set, throws NPE otherwise. */
  public DH getHierarchy() {
    return mDraweeHolder.getHierarchy();
  }

  /** Returns whether the hierarchy is set or not. */
  public boolean hasHierarchy() {
    return mDraweeHolder.hasHierarchy();
  }

  /** Gets the top-level drawable if hierarchy is set, null otherwise. */
  @Nullable public Drawable getTopLevelDrawable() {
    return mDraweeHolder.getTopLevelDrawable();
  }

  /** Sets the controller. */
  public void setController(@Nullable DraweeController draweeController) {
    mDraweeHolder.setController(draweeController);
    super.setImageDrawable(mDraweeHolder.getTopLevelDrawable());
  }

  /** Gets the controller if set, null otherwise. */
  @Nullable public DraweeController getController() {
    return mDraweeHolder.getController();
  }

  /** Returns whether the controller is set or not.  */
  public boolean hasController() {
    return mDraweeHolder.getController() != null;
  }

  @Override
  protected void onAttachedToWindow() {
    super.onAttachedToWindow();
    mDraweeHolder.onAttach();
  }

  @Override
  protected void onDetachedFromWindow() {
    super.onDetachedFromWindow();
    mDraweeHolder.onDetach();
  }

  @Override
  public void onStartTemporaryDetach() {
    super.onStartTemporaryDetach();
    mDraweeHolder.onDetach();
  }

  @Override
  public void onFinishTemporaryDetach() {
    super.onFinishTemporaryDetach();
    mDraweeHolder.onAttach();
  }

  @Override
  public boolean onTouchEvent(MotionEvent event) {
    if (mDraweeHolder.onTouchEvent(event)) {
      return true;
    }
    return super.onTouchEvent(event);
  }

  /**
   * Use this method only when using this class as an ordinary ImageView.
   * @deprecated Use {@link #setController(DraweeController)} instead.
   */
  @Override
  @Deprecated
  public void setImageDrawable(Drawable drawable) {
    mDraweeHolder.setController(null);
    super.setImageDrawable(drawable);
  }

  /**
   * Use this method only when using this class as an ordinary ImageView.
   * @deprecated Use {@link #setController(DraweeController)} instead.
   */
  @Override
  @Deprecated
  public void setImageBitmap(Bitmap bm) {
    mDraweeHolder.setController(null);
    super.setImageBitmap(bm);
  }

  /**
   * Use this method only when using this class as an ordinary ImageView.
   * @deprecated Use {@link #setController(DraweeController)} instead.
   */
  @Override
  @Deprecated
  public void setImageResource(int resId) {
    mDraweeHolder.setController(null);
    super.setImageResource(resId);
  }

  /**
   * Use this method only when using this class as an ordinary ImageView.
   * @deprecated Use {@link #setController(DraweeController)} instead.
   */
  @Override
  @Deprecated
  public void setImageURI(Uri uri) {
    mDraweeHolder.setController(null);
    super.setImageURI(uri);
  }

  @Override
  public String toString() {
    return Objects.toStringHelper(this)
        .add("holder", mDraweeHolder.toString())
        .toString();
  }
}