1 /*
2  * Copyright (C) 2013 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.bitmap.view;
18 
19 import android.content.Context;
20 import android.graphics.Bitmap;
21 import android.graphics.drawable.Drawable;
22 import android.net.Uri;
23 import android.os.Build;
24 import android.util.AttributeSet;
25 import android.widget.ImageView;
26 
27 import com.android.bitmap.drawable.BasicBitmapDrawable;
28 
29 /**
30  * A helpful ImageView replacement that can generally be used in lieu of ImageView.
31  * BitmapDrawableImageView has logic to unbind its BasicBitmapDrawable when it is detached from the
32  * window.
33  *
34  * If you are using this with RecyclerView,
35  * or any use-case where {@link android.view.View#onDetachedFromWindow} is
36  * not a good signal for unbind,
37  * makes sure you {@link #setShouldUnbindOnDetachFromWindow} to false.
38  */
39 public class BitmapDrawableImageView extends ImageView {
40     private static final boolean HAS_TRANSIENT_STATE_SUPPORTED =
41         Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN;
42     private static final boolean TEMPORARY = true;
43     private static final boolean PERMANENT = !TEMPORARY;
44 
45     private BasicBitmapDrawable mDrawable;
46     private boolean mShouldUnbindOnDetachFromWindow = true;
47     private boolean mAttachedToWindow;
48 
BitmapDrawableImageView(final Context context)49     public BitmapDrawableImageView(final Context context) {
50         this(context, null);
51     }
52 
BitmapDrawableImageView(final Context context, final AttributeSet attrs)53     public BitmapDrawableImageView(final Context context, final AttributeSet attrs) {
54         this(context, attrs, 0);
55     }
56 
BitmapDrawableImageView(final Context context, final AttributeSet attrs, final int defStyle)57     public BitmapDrawableImageView(final Context context, final AttributeSet attrs,
58             final int defStyle) {
59         super(context, attrs, defStyle);
60     }
61 
shouldUnbindOnDetachFromWindow()62   public boolean shouldUnbindOnDetachFromWindow() {
63     return mShouldUnbindOnDetachFromWindow;
64   }
65 
setShouldUnbindOnDetachFromWindow(boolean shouldUnbindOnDetachFromWindow)66   public void setShouldUnbindOnDetachFromWindow(boolean shouldUnbindOnDetachFromWindow) {
67         mShouldUnbindOnDetachFromWindow = shouldUnbindOnDetachFromWindow;
68     }
69 
70     /**
71      * Get the source drawable for this BitmapDrawableImageView.
72      * @return The source drawable casted to the given type, or null if the type does not match.
73      */
74     @SuppressWarnings("unchecked") // Cast to type parameter.
getTypedDrawable()75     public <E extends BasicBitmapDrawable> E getTypedDrawable() {
76         try {
77             return (E) mDrawable;
78         } catch (Exception ignored) {
79             return null;
80         }
81     }
82 
83     /**
84      * Set the given drawable as the source for this BitmapDrawableImageView.
85      * @param drawable The source drawable.
86      */
setTypedDrawable(E drawable)87     public <E extends BasicBitmapDrawable> void setTypedDrawable(E drawable) {
88         super.setImageDrawable(drawable);
89         if (drawable != mDrawable) {
90             unbindDrawable();
91         }
92         mDrawable = drawable;
93     }
94 
unbindDrawable()95     public void unbindDrawable() {
96         unbindDrawable(PERMANENT);
97     }
98 
unbindDrawable(boolean temporary)99     private void unbindDrawable(boolean temporary) {
100         if (mDrawable != null) {
101             mDrawable.unbind(temporary);
102         }
103     }
104 
105     @Override
setImageResource(final int resId)106     public void setImageResource(final int resId) {
107         super.setImageResource(resId);
108         unbindDrawable();
109         mDrawable = null;
110     }
111 
112     @Override
setImageURI(final Uri uri)113     public void setImageURI(final Uri uri) {
114         super.setImageURI(uri);
115         unbindDrawable();
116         mDrawable = null;
117     }
118 
119     @Override
setImageDrawable(final Drawable drawable)120     public void setImageDrawable(final Drawable drawable) {
121         super.setImageDrawable(drawable);
122         unbindDrawable();
123         mDrawable = null;
124     }
125 
126     @Override
setImageBitmap(final Bitmap bm)127     public void setImageBitmap(final Bitmap bm) {
128         super.setImageBitmap(bm);
129         unbindDrawable();
130         mDrawable = null;
131     }
132 
133     @Override
onAttachedToWindow()134     protected void onAttachedToWindow() {
135         super.onAttachedToWindow();
136         mAttachedToWindow = true;
137         if (mDrawable != null && mDrawable.getKey() == null
138               && mDrawable.getPreviousKey() != null && mShouldUnbindOnDetachFromWindow) {
139             mDrawable.bind(mDrawable.getPreviousKey());
140         }
141     }
142 
143     @Override
onDetachedFromWindow()144     protected void onDetachedFromWindow() {
145         super.onDetachedFromWindow();
146         mAttachedToWindow = false;
147         if (HAS_TRANSIENT_STATE_SUPPORTED && !hasTransientState()
148                 && mShouldUnbindOnDetachFromWindow) {
149             unbindDrawable(TEMPORARY);
150         }
151     }
152 
153     @Override
setHasTransientState(boolean hasTransientState)154     public void setHasTransientState(boolean hasTransientState) {
155         super.setHasTransientState(hasTransientState);
156         if (!hasTransientState && !mAttachedToWindow && mShouldUnbindOnDetachFromWindow) {
157             unbindDrawable(TEMPORARY);
158         }
159     }
160 
161     @Override
onRtlPropertiesChanged(int layoutDirection)162     public void onRtlPropertiesChanged(int layoutDirection) {
163         super.onRtlPropertiesChanged(layoutDirection);
164         if (mDrawable != null) {
165           mDrawable.setLayoutDirectionLocal(layoutDirection);
166         }
167     }
168 }
169