Drawable与Bitmap（转）

Drawable

以下这个是测试加载1000个Drawable对象的代码：

public class Main extends Activity

{

    int number = 1000;

    Drawable[] array;

    @Override

    public void onCreate(Bundle savedInstanceState)

    {

       super.onCreate(savedInstanceState);

       setContentView(R.layout.main);

        array = new BitmapDrawable[number];

        for(int i = 0; i < number; i++)

        {

            Log.e("", "测试第" + (i+1) + "张图片");

            array[i] = getResources().getDrawable(R.drawable.img);

        }

    }

}

输出结果：

04-07 21:49:25.248: D/szipinf(7828): Initializing inflate state

04-07 21:49:25.398: E/(7828): 测试第1张图片

04-07 21:49:25.658: D/dalvikvm(7828): GC_EXTERNAL_ALLOC freed 48K, 50% free 2692K/5379K, external 0K/0K, paused 24ms

04-07 21:49:25.748: E/(7828): 测试第2张图片

04-07 21:49:25.748: E/(7828): 测试第3张图片

………………

………………

04-07 21:49:26.089: E/(7828): 测试第998张图片

04-07 21:49:26.089: E/(7828): 测试第999张图片

04-07 21:49:26.089: E/(7828): 测试第1000张图片

程序没有报错，正常运行，加载1000个Drawable对象没问题。

Bitmap

下面再来看一下加载1000个Bitmap对象的代码：

public class Main extends Activity

{

    int number = 1000;

    Bitmap bitmap[];

    @Override

    public void onCreate(Bundle savedInstanceState)

    {

       super.onCreate(savedInstanceState);

       setContentView(R.layout.main);

       bitmap = new Bitmap[number];

       for (int i = 0; i < number; i++)

       {

           Log.e("", "测试第" + (i+1) + "张图片");

           bitmap[i] = BitmapFactory.decodeResource(getResources(), R.drawable.img);

       }

    }

}

输出结果：

04-07 22:06:05.344: D/szipinf(7937): Initializing inflate state

04-07 22:06:05.374: E/(7937): 测试第1张图片

04-07 22:06:05.544: D/dalvikvm(7937): GC_EXTERNAL_ALLOC freed 51K, 50% free 2692K/5379K, external 0K/0K, paused 40ms

04-07 22:06:05.664: E/(7937): 测试第2张图片

04-07 22:06:05.774: D/dalvikvm(7937): GC_EXTERNAL_ALLOC freed 1K, 50% free 2691K/5379K, external 6026K/7525K, paused 31ms

04-07 22:06:05.834: E/(7937): 测试第3张图片

04-07 22:06:05.934: D/dalvikvm(7937): GC_EXTERNAL_ALLOC freed <1K, 50% free 2691K/5379K, external 12052K/14100K, paused 24ms

04-07 22:06:06.004: E/(7937): 测试第4张图片

04-07 22:06:06.124: D/dalvikvm(7937): GC_EXTERNAL_ALLOC freed <1K, 50% free 2691K/5379K, external 18078K/20126K, paused 27ms

04-07 22:06:06.204: E/(7937): 测试第5张图片

04-07 22:06:06.315: D/dalvikvm(7937): GC_EXTERNAL_ALLOC freed <1K, 50% free 2691K/5379K, external 24104K/26152K, paused 26ms

04-07 22:06:06.395: E/(7937): 测试第6张图片

04-07 22:06:06.495: D/dalvikvm(7937): GC_EXTERNAL_ALLOC freed <1K, 50% free 2691K/5379K, external 30130K/32178K, paused 22ms

04-07 22:06:06.565: E/(7937): 测试第7张图片

04-07 22:06:06.665: D/dalvikvm(7937): GC_EXTERNAL_ALLOC freed <1K, 50% free 2691K/5379K, external 36156K/38204K, paused 22ms

04-07 22:06:06.745: E/(7937): 测试第8张图片

04-07 22:06:06.845: D/dalvikvm(7937): GC_EXTERNAL_ALLOC freed 2K, 51% free 2689K/5379K, external 42182K/44230K, paused 23ms

04-07 22:06:06.845: E/dalvikvm-heap(7937): 6170724-byte external allocation too large for this process.

04-07 22:06:06.885: I/dalvikvm-heap(7937): Clamp target GC heap from 48.239MB to 48.000MB

04-07 22:06:06.885: E/GraphicsJNI(7937): VM won't let us allocate 6170724 bytes

04-07 22:06:06.885: D/dalvikvm(7937): GC_FOR_MALLOC freed <1K, 51% free 2689K/5379K, external 42182K/44230K, paused 25ms

04-07 22:06:06.885: D/AndroidRuntime(7937): Shutting down VM

04-07 22:06:06.885: W/dalvikvm(7937): threadid=1: thread exiting with uncaught exception (group=0x40015560)

04-07 22:06:06.885: E/AndroidRuntime(7937): FATAL EXCEPTION: main

04-07 22:06:06.885: E/AndroidRuntime(7937): java.lang.OutOfMemoryError: bitmap size exceeds VM budget

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.graphics.Bitmap.nativeCreate(Native Method)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.graphics.Bitmap.createBitmap(Bitmap.java:477)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.graphics.Bitmap.createBitmap(Bitmap.java:444)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.graphics.Bitmap.createScaledBitmap(Bitmap.java:349)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.graphics.BitmapFactory.finishDecode(BitmapFactory.java:498)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:473)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.graphics.BitmapFactory.decodeResourceStream(BitmapFactory.java:336)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.graphics.BitmapFactory.decodeResource(BitmapFactory.java:359)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.graphics.BitmapFactory.decodeResource(BitmapFactory.java:385)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at bassy.test.drawable.Main.onCreate(Main.java:37)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1722)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1784)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.app.ActivityThread.access$1500(ActivityThread.java:123)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.app.ActivityThread$H.handleMessage(ActivityThread.java:939)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.os.Handler.dispatchMessage(Handler.java:99)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.os.Looper.loop(Looper.java:130)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at android.app.ActivityThread.main(ActivityThread.java:3835)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at java.lang.reflect.Method.invokeNative(Native Method)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at java.lang.reflect.Method.invoke(Method.java:507)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:847)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:605)

04-07 22:06:06.885: E/AndroidRuntime(7937):   at dalvik.system.NativeStart.main(Native Method)

看看上面的输出，才加载到第8张图片，程序就报错了“java.lang.OutOfMemoryError: bitmap size exceeds VM budget”。通过上面的例子，可以看清楚地看出来，使用Drawable保存图片对象，占用更小的内存空间。而使用Biamtp对象，则会占用很大内存空间，很容易就出现OOM了！

下面我们再来看一个例子，这个也是加载Bitmap对象。只不过，之次不是使用BitmapFactory的decodeResource方法，而是使用decodeStream方法，看代码。

public class Main extends Activity

{

    int number = 1000;

    Bitmap bitmap[];

    @Override

    public void onCreate(Bundle savedInstanceState)

    {

       super.onCreate(savedInstanceState);

       setContentView(R.layout.main);

       bitmap = new Bitmap[number];

       for (int i = 0; i < number; i++)

       {

           Log.e("", "测试第" + (i+1) + "张图片");

           bitmap[i] =BitmapFactory.decodeStream(getResources().openRawResource(R.drawable.img));//这里换了方法

       }

    }

}

输出结果：

04-07 22:16:12.676: E/(8091): 测试第561张图片

04-07 22:16:12.756: E/(8091): 测试第562张图片

04-07 22:16:12.826: E/(8091): 测试第563张图片

04-07 22:16:12.906: E/(8091): 测试第564张图片

04-07 22:16:12.906: D/skia(8091): ---------- mmap failed for imageref_ashmem size=2744320 err=12

04-07 22:16:12.906: E/(8091): 测试第565张图片

04-07 22:16:12.906: D/skia(8091): ---------- mmap failed for imageref_ashmem size=2744320 err=12

04-07 22:16:12.906: E/(8091): 测试第566张图片

04-07 22:16:12.916: E/filemap(8091): mmap(0,416798) failed: Out of memory

04-07 22:16:12.916: D/filemap(8091): munmap(0x0, 0) failed

04-07 22:16:12.916: W/asset(8091): create map from entry failed

04-07 22:16:12.916: D/AndroidRuntime(8091): Shutting down VM

04-07 22:16:12.916: W/dalvikvm(8091): threadid=1: thread exiting with uncaught exception (group=0x40015560)

04-07 22:16:12.936: E/AndroidRuntime(8091): FATAL EXCEPTION: main

04-07 22:16:12.936: E/AndroidRuntime(8091): java.lang.RuntimeException: Unable to start activity ComponentInfo{bassy.test.drawable/bassy.test.drawable.Main}: android.content.res.Resources$NotFoundException: File res/drawable-mdpi/img.png from drawable resource ID #0x7f020001

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1768)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1784)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.app.ActivityThread.access$1500(ActivityThread.java:123)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.app.ActivityThread$H.handleMessage(ActivityThread.java:939)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.os.Handler.dispatchMessage(Handler.java:99)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.os.Looper.loop(Looper.java:130)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.app.ActivityThread.main(ActivityThread.java:3835)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at java.lang.reflect.Method.invokeNative(Native Method)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at java.lang.reflect.Method.invoke(Method.java:507)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:847)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:605)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at dalvik.system.NativeStart.main(Native Method)

04-07 22:16:12.936: E/AndroidRuntime(8091): Caused by: android.content.res.Resources$NotFoundException: File res/drawable-mdpi/img.png from drawable resource ID #0x7f020001

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.content.res.Resources.openRawResource(Resources.java:860)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.content.res.Resources.openRawResource(Resources.java:836)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at bassy.test.drawable.Main.onCreate(Main.java:43)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1722)

04-07 22:16:12.936: E/AndroidRuntime(8091):   ... 11 more

04-07 22:16:12.936: E/AndroidRuntime(8091): Caused by: java.io.FileNotFoundException: res/drawable-mdpi/img.png

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.content.res.AssetManager.openNonAssetNative(Native Method)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.content.res.AssetManager.openNonAsset(AssetManager.java:429)

04-07 22:16:12.936: E/AndroidRuntime(8091):   at android.content.res.Resources.openRawResource(Resources.java:857)

04-07 22:16:12.936: E/AndroidRuntime(8091):   ... 15 more

从上面可以看出，程序在加载到第566张的时候，就出现了OOM错误。不过，跟第2个例子比起来，你会发现，程序可以加载更多的图片。这说明了使用BitmapFactory的decodeResource方法会占据大量内存，而使用使用decodeStream方法，则占据更小的内存。

我是天王盖地虎的分割线

从上面三个例子，可以看出，用第一种方法（即用Drawable加载图片）可以加载更加的图片，加载32张图片的时间约为0.01秒！我试着把Drawable的数量调至1000000，程序在运行时，停在了153761张图片里，手机提示，“应用程序无响应…”

个人猜测，Drawable应该不属于常驻内存的对象，不然的话，不可能不会出现OOM的～～

刚才又做了个测试，把第一个例子中的

array[i] = getResources().getDrawable(R.drawable.img);

方法换成了

array[i] = Drawable.createFromStream(getResources().openRawResource(R.drawable.img), null);

结果和第三个例子一样，在第566张图片中，出现了OOM错误！而且，加载的时间都是一样～～

我是天王盖地虎的分割线

Bitmap转Drawable

Bitmap bm=xxx; //xxx根据你的情况获取

BitmapDrawable bd=BitmapDrawable(bm);

Android开发网提示因为BtimapDrawable是Drawable的子类，最终直接使用bd对象即可。

Drawable转Bitmap

转成Bitmap对象后，可以将Drawable对象通过Android的SK库存成一个字节输出流，最终还可以保存成为jpg和png的文件。

Drawable d=xxx; //xxx根据自己的情况获取drawable

BitmapDrawable bd = (BitmapDrawable) d;

Bitmap bm = bd.getBitmap();

最终bm就是我们需要的Bitmap对象了。

参考：http://blog.csdn.net/ygc973797893/article/details/7620352

Drawable与Bitmap（转）的更多相关文章

Android Drawable、Bitmap、byte[]之间的转换
转自http://blog.csdn.net/june5253/article/details/7826597 1.Bitmap-->Drawable Bitmap drawable2Bitma ...
Drawable和Bitmap区别
Bitmap - 称作位图,一般位图的文件格式后缀为bmp,当然编码器也有很多如RGB565.RGB888.作为一种逐像素的显示对象执行效率高,但是缺点也很明显存储效率低.我们理解为一种存储对象比较好 ...
获取应用图标，Drawable 转bitmap
获取应用图标: PackageManager p = context.getPackageManager(); Drawable draw=null; ApplicationInfo info; tr ...
简单谈谈Resource，Drawable和Bitmap之间的转换
一直接触这些东西,还是归个类整理一下比较好. Resource -> Drawable Drawable draw1 = this.getResources().getDrawable(R.dr ...
android 获取资源文件 r.drawable中的图片转换为drawable、bitmap
1.R-Drawable Resources resources = mContext.getResources(); Drawable drawable = resources.getDrawabl ...
Android -- Drawable与Bitmap测试
Drawable 以下这个是测试加载10 ...
Drawable和Bitmap转换
一.Bitmap转Drawable Bitmap mBitMap=getYourBitMap(); //getYourBitMap()是你获取BitMap的方法 BitmapDrawable mBit ...
Drawable、Bitmap、byte[]之间的转换
android在处理一写图片资源的时候,会进行一些类型的转换: 1 Drawable → Bitmap 的简单方法 ((BitmapDrawable)res.getDrawable(R.drawabl ...
Drawable与Bitmap 自定义
Drawable简介 Drawable是Android平下通用的图形对象,它可以装载常用格式的图像,比如GIF.PNG.JPG,当然也支持BMP.相比于View,我们并不需要去考虑如何measure. ...

随机推荐

dede列表标签递增数字生成
今天给人家调试程序,用到[field:global name=autoindex/ ] 调用指定频道.而频道前面需要加CSS代码,CSS代码正好是按序号排列的忽然发现,是从0开始. 于是修改了一下代 ...
phpcms v9 get调用标签整理
常见的phpcms标签调用 1.调用本系统单条数据(调用ID为1的信息,标题长度不超过25个汉字,显示更新日期): "select * from phpcms_content where ...
用Web Picasa API搭建站内相册
在flickr时代,为了专门把站内嵌入相册,还专门写了一篇文章把Flickr相册搬回家.flickr被墙之后,我就把个人相册转到了Web Picasa上.用Picasa Web就简单多了,官方提供了S ...
如何执行一个mysql的sql脚本文件
sql脚本是包含一到多个sql命令的sql语句,我们可以将这些sql脚本放在一个文本文件中(我们称之为“sql脚本文件”),然后通过相关的命令执行这个sql脚本文件.基本步骤如下:一.创建包含sql命 ...
cygwin编译ffmpeg移植到android平台问题集锦
编译环境: windows xp Cygwin 1.1.3.1 NDK r9 1.提示各种command not found 比如 ./config.sh: line 6: $'--arch=arm\ ...
Tiling
地址:http://poj.org/problem?id=2506 递推公式::f[x]=f[x-1]+f[x-2]*2 需要用到大数. #include<stdio.h> #includ ...
c# 集合ArrayList；特殊集合Stack、Queue
一) ArrayList 1.foreach遍历数组中各个元素,执行内部语句 2. 3. 4. myarry.Clear();//将集合清空 bool b = myarry.Contains(3 ...
【HDOJ】1885 Key Task
状态压缩+BFS,一次AC. /* 1885 */ #include <iostream> #include <queue> #include <cstring> ...
学习C++所需看的书和顺序
初学: <C++ 编程思想> <C++ Primer><The C++ Programming Language> 提高: <C++ 的发展与演化> & ...
phpMyAdmin 跨站脚本漏洞
漏洞名称: phpMyAdmin 跨站脚本漏洞 CNNVD编号: CNNVD-201307-647 发布时间: 2013-08-09 更新时间: 2013-08-09 危害等级: 低危漏洞类型: ...

Drawable与Bitmap（转）

Drawable与Bitmap（转）的更多相关文章

随机推荐

热门专题