{"id":2153,"date":"2013-09-13T08:02:40","date_gmt":"2013-09-13T00:02:40","guid":{"rendered":"http:\/\/kuki.idv.tw\/?p=2153"},"modified":"2013-09-13T08:02:40","modified_gmt":"2013-09-13T00:02:40","slug":"%e9%9d%9e%e5%8e%9f%e5%89%b5android-%e6%80%a7%e8%83%bd%e5%84%aa%e5%8c%96%e5%bb%ba%e8%ad%b0%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/www.kuki.idv.tw\/?p=2153","title":{"rendered":"[\u975e\u539f\u5275]Android \u6027\u80fd\u512a\u5316\u5efa\u8b70\u65b9\u6cd5"},"content":{"rendered":"
\n

\u4f86\u6e90:Android <\/b>\u6027\u80fd\u512a\u5316<\/b>\u5efa\u8b70<\/b><\/a>\u65b9\u6cd5<\/a><\/b><\/b><\/p>\n<\/div>\n

\u5c0d\u65bc\u4e00\u4e9bAndroid\u5c08\u6848\uff0c\u5f71\u97ff\u6027\u80fd\u74f6\u9838\u7684\u4e3b\u8981\u662fAndroid\u81ea\u5df1\u8a18\u61b6\u9ad4\u7ba1\u7406\u6a5f\u5236\u554f\u984c\uff0c\u76ee\u524d\u624b\u6a5f\u5ee0\u5546\u5c0dRAM\u90fd\u6bd4\u8f03\u541d\u55c7\uff0c\u5c0d\u65bc\u8edf\u9ad4\u7684\u6d41\u66a2\u6027\u4f86\u8aaaRAM\u5c0d\u6027\u80fd\u7684\u5f71\u97ff\u5341\u5206\u654f\u611f\uff0c\u9664\u4e86 \u512a\u5316Dalvik\u865b\u64ec\u6a5f\u5668\u7684\u5806\u8a18\u61b6\u9ad4\u5206\u914d\u5916\uff0c\u6211\u5011\u9084\u53ef\u4ee5\u5f37\u5236\u5b9a\u7fa9\u81ea\u5df1\u8edf\u9ad4\u7684\u5c0d\u8a18\u61b6\u9ad4\u5927\u5c0f\u3002<\/p>\n

\u5c0d\u65bc\u4e00\u4e9bAndroid\u5c08\u6848\uff0c\u5f71\u97ff\u6027\u80fd\u74f6\u9838\u7684\u4e3b\u8981\u662fAndroid\u81ea\u5df1\u8a18\u61b6\u9ad4\u7ba1\u7406\u6a5f\u5236\u554f\u984c\uff0c\u76ee\u524d\u624b\u6a5f\u5ee0\u5546\u5c0dRAM\u90fd\u6bd4\u8f03\u541d\u55c7\uff0c\u5c0d\u65bc\u8edf\u9ad4\u7684\u6d41\u66a2\u6027\u4f86\u8aaaRAM\u5c0d\u6027\u80fd\u7684\u5f71\u97ff\u5341\u5206\u654f\u611f\uff0c\u9664\u4e86 \u512a\u5316Dalvik\u865b\u64ec\u6a5f\u5668\u7684\u5806\u8a18\u61b6\u9ad4\u5206\u914d\u5916\uff0c\u6211\u5011\u9084\u53ef\u4ee5\u5f37\u5236\u5b9a\u7fa9\u81ea\u5df1\u8edf\u9ad4\u7684\u5c0d\u8a18\u61b6\u9ad4\u5927\u5c0f\uff0c\u6211\u5011\u4f7f\u7528Dalvik\u63d0\u4f9b\u7684 dalvik.system.VMRuntime\u985e\u4f86\u8a2d\u7f6e\u6700\u5c0f\u5806\u8a18\u61b6\u9ad4\u70ba\u4f8b:

<\/p>\n

    \n
  1. private<\/b>\u00a0final<\/b>\u00a0static<\/b>\u00a0int<\/b>\u00a0CWJ_HEAP_SIZE\u00a0=\u00a06*\u00a01024*\u00a01024\u00a0;<\/li>\n<\/ol>\n


    <\/p>\n

      \n
    1. VMRuntime.getRuntime().setMinimumHeapSize(CWJ_HEAP_SIZE);<\/li>\n<\/ol>\n

      \/\/\u8a2d\u7f6e\u6700\u5c0fheap\u8a18\u61b6\u9ad4\u70ba6MB\u5927\u5c0f\u3002\u7576\u7136\u5c0d\u65bc\u8a18\u61b6\u9ad4\u5403\u7dca\u4f86\u8aaa\u9084\u53ef\u4ee5\u901a\u904e\u624b\u52d5\u5e72\u6d89GC\u53bb\u8655\u7406


      bitmap \u8a2d\u7f6e\u5716\u7247\u5c3a\u5bf8\uff0c\u907f\u514d \u8a18\u61b6\u9ad4\u6ea2\u51fa OutOfMemoryError\u7684\u512a\u5316\u65b9\u6cd5
      \u2605android \u4e2d\u7528bitmap \u6642\u5f88\u5bb9\u6613\u8a18\u61b6\u9ad4\u6ea2\u51fa\uff0c\u5831\u5982\u4e0b\u932f\u8aa4\uff1aJava.lang.OutOfMemoryError : bitmap size exceeds VM budget

      \u25cf \u4e3b\u8981\u662f\u52a0\u4e0a\u9019\u6bb5\uff1a
      <\/p>\n

        \n
      1. BitmapFactory.Options\u00a0options\u00a0=\u00a0new<\/b>\u00a0BitmapFactory.Options();<\/li>\n
      2. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0options.inSampleSize\u00a0=\u00a02;<\/li>\n<\/ol>\n



        \n\u25cf eg1\uff1a(\u901a\u904eUri\u53d6\u5716\u7247)
        <\/p>\n

          \n
        1. private<\/b>\u00a0ImageView\u00a0preview;<\/li>\n
        2. BitmapFactory.Options\u00a0options\u00a0=\u00a0new<\/b>\u00a0BitmapFactory.Options();<\/li>\n
        3. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0options.inSampleSize\u00a0=\u00a02;\/\/\u5716\u7247\u5bec\u9ad8\u90fd\u70ba\u539f\u4f86\u7684\u4e8c\u5206\u4e4b\u4e00\uff0c\u5373\u5716\u7247\u70ba\u539f\u4f86\u7684\u56db\u5206\u4e4b\u4e00<\/li>\n
        4. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0Bitmap\u00a0bitmap\u00a0=\u00a0BitmapFactory.decodeStream(cr<\/li>\n
        5. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0.openInputStream(uri),\u00a0null<\/b>,\u00a0options);<\/li>\n
        6. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0preview.setImageBitmap(bitmap);<\/li>\n<\/ol>\n


          \u4ee5\u4e0a\u4ee3\u78bc\u53ef\u4ee5\u512a\u5316\u8a18\u61b6\u9ad4\u6ea2\u51fa\uff0c\u4f46\u5b83\u53ea\u662f\u6539\u8b8a\u5716\u7247\u5927\u5c0f\uff0c\u4e26\u4e0d\u80fd\u5fb9\u5e95\u89e3\u6c7a\u8a18\u61b6\u9ad4\u6ea2\u51fa\u3002
          \u25cf eg2:\uff08\u901a\u904e\u8def\u5f91\u53bb\u5716\u7247\uff09
          <\/p>\n

            \n
          1. private<\/b>\u00a0ImageView\u00a0preview;<\/li>\n
          2. private<\/b>\u00a0String\u00a0fileName=\u00a0“\/sdcard\/DCIM\/Camera\/2010-05-14\u00a016.01.44.jpg”;<\/li>\n
          3. BitmapFactory.Options\u00a0options\u00a0=\u00a0new<\/b>\u00a0BitmapFactory.Options();<\/li>\n
          4. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0options.inSampleSize\u00a0=\u00a02;\/\/\u5716\u7247\u5bec\u9ad8\u90fd\u70ba\u539f\u4f86\u7684\u4e8c\u5206\u4e4b\u4e00\uff0c\u5373\u5716\u7247\u70ba\u539f\u4f86\u7684\u56db\u5206\u4e4b\u4e00<\/li>\n
          5. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0Bitmap\u00a0b\u00a0=\u00a0BitmapFactory.decodeFile(fileName,\u00a0options);<\/li>\n
          6. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0preview.setImageBitmap(b);<\/li>\n
          7. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0filePath.setText(fileName);<\/li>\n<\/ol>\n



            \n\u2605Android <\/b>\u9084\u6709\u4e00\u4e9b\u6027\u80fd\u512a\u5316\u7684\u65b9\u6cd5\uff1a<\/b>
            \u25cf\u00a0\u00a0\u9996\u5148\u8a18\u61b6\u9ad4\u65b9\u9762\uff0c\u53ef\u4ee5\u53c3\u8003 Android\u5806\u8a18\u61b6\u9ad4\u4e5f\u53ef\u81ea\u5df1\u5b9a\u7fa9\u5927\u5c0f \u548c \u512a\u5316Dalvik\u865b\u64ec\u6a5f\u5668\u7684\u5806\u8a18\u61b6\u9ad4\u5206\u914d

            \u25cf\u00a0\u00a0\u57fa\u790e\u985e\u578b\u4e0a\uff0c\u56e0\u70baJava\u6c92\u6709\u5be6\u969b\u7684\u6307\u6a19\uff0c\u5728\u654f\u611f\u904b\u7b97\u65b9\u9762\u9084\u662f\u8981\u501f\u52a9NDK\u4f86\u5b8c\u6210\u3002\u9019\u9ede\u6bd4\u8f03\u6709\u610f\u601d\u7684\u662fGoogle \u63a8\u51faNDK\u53ef\u80fd\u662f\u5e6b\u52a9\u904a\u6232\u958b\u767c\u4eba\u54e1\uff0c\u6bd4\u5982OpenGL ES\u7684\u652f\u6301\u6709\u660e\u986f\u7684\u6539\u89c0\uff0c\u672c\u5730\u4ee3\u78bc\u64cd\u4f5c\u5716\u5f62\u4ecb\u9762\u662f\u5f88\u5fc5\u8981\u7684\u3002

            \u25cf\u00a0\u00a0\u5716\u5f62\u7269\u4ef6\u512a\u5316\uff0c\u9019\u88e1\u8981\u8aaa\u7684\u662fAndroid\u4e0a\u7684Bitmap\u7269\u4ef6\u92b7\u6bc0\uff0c\u53ef\u4ee5\u501f\u52a9recycle()\u65b9\u6cd5\u986f\u793a\u8b93GC\u56de\u6536\u4e00\u500bBitmap\u7269\u4ef6\uff0c\u901a\u5e38\u5c0d\u4e00\u500b\u4e0d\u7528\u7684Bitmap\u53ef\u4ee5\u4f7f\u7528\u4e0b\u9762\u7684\u65b9\u5f0f\uff0c\u5982

            <\/p>\n

              \n
            1. if<\/b>(bitmapObject.isRecycled()==false<\/b>)\u00a0\/\/\u5982\u679c\u6c92\u6709\u56de\u6536<\/li>\n
            2. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0bitmapObject.recycle();<\/li>\n<\/ol>\n



              \n\u25cf\u00a0\u00a0\u76ee\u524d\u7cfb\u7d71\u5c0d\u52d5\u756b\u652f\u63f4\u6bd4\u8f03\u5f31\u667a\u5c0d\u65bc\u5e38\u898f\u61c9\u7528\u7684\u88dc\u9593\u904e\u6e21\u6548\u679c\u53ef\u4ee5\uff0c\u4f46\u662f\u5c0d\u65bc\u904a\u6232\u800c\u8a00\u4e00\u822c\u7684\u7f8e\u5de5\u53ef\u80fd\u7fd2\u6163\u4e86GIF\u65b9\u5f0f\u7684\u7d71\u4e00\u8655\u7406\uff0c\u76ee\u524dAndroid\u7cfb\u7d71\u50c5\u80fd\u9810\u89bdGIF\u7684\u7b2c\u4e00\u5e40\uff0c\u53ef\u4ee5\u501f\u52a9J2ME\u4e2d\u901a\u904e\u57f7\u884c\u7dd2\u548c\u81ea\u5df1\u5beb\u89e3\u6790\u5668\u7684\u65b9\u5f0f\u4f86\u8b80\u53d6GIF89\u683c\u5f0f\u7684\u8cc7\u6e90\u3002

              \u25cf \u5c0d\u65bc\u5927\u591a\u6578Android\u624b\u6a5f\u6c92\u6709\u904e\u591a\u7684\u7269\u7406\u6309\u9375\u53ef\u80fd\u6211\u5011\u9700\u8981\u60f3\u50cf\u4e0b\u4e86\u505a\u597d\u624b\u52e2\u8b58\u5225 GestureDetector \u548c\u91cd\u529b\u611f\u61c9\u4f86\u5be6\u73fe\u64cd\u63a7\u3002\u901a\u5e38\u6211\u5011\u9084\u8981\u8003\u616e\u8aa4\u64cd\u4f5c\u554f\u984c\u7684\u964d\u566a\u8655\u7406\u3002

              Android\u5806\u8a18\u61b6\u9ad4\u4e5f\u53ef\u81ea\u5df1\u5b9a\u7fa9\u5927\u5c0f

              \u00a0 \u00a0\u5c0d\u65bc\u4e00\u4e9b\u5927\u578bAndroid\u5c08\u6848\u6216\u904a\u6232\u4f86\u8aaa\u5728\u6f14\u7b97\u6cd5\u8655\u7406\u4e0a\u6c92\u6709\u554f\u984c\u5916\uff0c\u5f71\u97ff\u6027\u80fd\u74f6\u9838\u7684\u4e3b\u8981\u662fAndroid\u81ea\u5df1\u8a18\u61b6\u9ad4\u7ba1\u7406\u6a5f\u5236\u554f\u984c\uff0c\u76ee\u524d\u624b\u6a5f\u5ee0\u5546\u5c0dRAM\u90fd\u6bd4\u8f03\u541d\u55c7\uff0c\u5c0d\u65bc\u8edf\u9ad4\u7684\u6d41\u66a2\u6027\u4f86\u8aaaRAM\u5c0d\u6027\u80fd\u7684\u5f71\u97ff\u5341\u5206\u654f\u611f\uff0c\u9664\u4e86\u4e0a\u6b21Android\u958b\u767c\u7db2\u63d0\u5230\u7684\u512a\u5316Dalvik\u865b\u64ec\u6a5f\u5668\u7684\u5806\u8a18\u61b6\u9ad4\u5206\u914d\u5916\uff0c\u6211\u5011\u9084\u53ef\u4ee5\u5f37\u5236\u5b9a\u7fa9\u81ea\u5df1\u8edf\u9ad4\u7684\u5c0d\u8a18\u61b6\u9ad4\u5927\u5c0f\uff0c\u6211\u5011\u4f7f\u7528Dalvik\u63d0\u4f9b\u7684 dalvik.system.VMRuntime\u985e\u4f86\u8a2d\u7f6e\u6700\u5c0f\u5806\u8a18\u61b6\u9ad4\u70ba\u4f8b:

              <\/p>\n

                \n
              1. private<\/b>\u00a0final<\/b>\u00a0static<\/b>\u00a0int<\/b>\u00a0CWJ_HEAP_SIZE\u00a0=\u00a06*\u00a01024*\u00a01024\u00a0;<\/li>\n<\/ol>\n


                <\/p>\n

                  \n
                1. VMRuntime.getRuntime().setMinimumHeapSize(CWJ_HEAP_SIZE);<\/li>\n<\/ol>\n

                  \/\/\u8a2d\u7f6e\u6700\u5c0fheap\u8a18\u61b6\u9ad4\u70ba6MB\u5927\u5c0f\u3002\u7576\u7136\u5c0d\u65bc\u8a18\u61b6\u9ad4\u5403\u7dca\u4f86\u8aaa\u9084\u53ef\u4ee5\u901a\u904e\u624b\u52d5\u5e72\u6d89GC\u53bb\u8655\u7406\uff0c\u6211\u5011\u5c07\u5728\u4e0b\u6b21\u63d0\u5230\u5177\u9ad4\u61c9\u7528\u3002

                  \u512a\u5316<\/b>Dalvik<\/b>\u865b\u64ec\u6a5f\u5668\u7684\u5806\u8a18\u61b6\u9ad4\u5206\u914d<\/b>

                  \u5c0d\u65bcAndroid\u5e73\u81fa\u4f86\u8aaa\uff0c\u5176\u8a17\u7ba1\u5c64\u4f7f\u7528\u7684Dalvik JavaVM\u5f9e\u76ee\u524d\u7684\u8868\u73fe\u4f86\u770b\u9084\u6709\u5f88\u591a\u5730\u65b9\u53ef\u4ee5\u512a\u5316\u8655\u7406\uff0c\u6bd4\u5982\u6211\u5011\u5728\u958b\u767c\u4e00\u4e9b\u5927\u578b\u904a\u6232\u6216\u8017\u8cc7\u6e90\u7684\u61c9\u7528\u4e2d\u53ef\u80fd\u8003\u616e\u624b\u52d5\u5e72\u6d89GC\u8655\u7406\uff0c\u4f7f\u7528 dalvik.system.VMRuntime\u985e\u63d0\u4f9b\u7684setTargetHeapUtilization\u65b9\u6cd5\u53ef\u4ee5\u589e\u5f37\u7a0b\u5f0f\u5806\u8a18\u61b6\u9ad4\u7684\u8655\u7406\u6548\u7387\u3002\u7576\u7136\u5177\u9ad4\u539f\u7406\u6211\u5011\u53ef\u4ee5\u53c3\u8003\u958b\u6e90\u5de5\u7a0b\uff0c\u9019\u88e1\u6211\u5011\u50c5\u8aaa\u4e0b\u4f7f\u7528\u65b9\u6cd5:\u00a0 \u00a0private final static floatTARGET_HEAP_UTILIZATION = 0.75f; \u5728\u7a0b\u5f0fonCreate\u6642\u5c31\u53ef\u4ee5\u8abf\u7528 VMRuntime.getRuntime().setTargetHeapUtilization(TARGET_HEAP_UTILIZATION); \u5373\u53ef\u3002<\/p>\n

                   <\/p>\n","protected":false},"excerpt":{"rendered":"

                  \u4f86\u6e90:Android \u6027\u80fd\u512a\u5316\u5efa\u8b70\u65b9\u6cd5 \u5c0d\u65bc\u4e00\u4e9bAndroid\u5c08\u6848\uff0c\u5f71\u97ff\u6027\u80fd\u74f6\u9838\u7684\u4e3b\u8981\u662fAndroid\u81ea\u5df1\u8a18\u61b6 … \u95b1\u8b80\u5168\u6587\u3008[\u975e\u539f\u5275]Android \u6027\u80fd\u512a\u5316\u5efa\u8b70\u65b9\u6cd5\u3009<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/www.kuki.idv.tw\/index.php?rest_route=\/wp\/v2\/posts\/2153"}],"collection":[{"href":"https:\/\/www.kuki.idv.tw\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.kuki.idv.tw\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.kuki.idv.tw\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.kuki.idv.tw\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2153"}],"version-history":[{"count":2,"href":"https:\/\/www.kuki.idv.tw\/index.php?rest_route=\/wp\/v2\/posts\/2153\/revisions"}],"predecessor-version":[{"id":2155,"href":"https:\/\/www.kuki.idv.tw\/index.php?rest_route=\/wp\/v2\/posts\/2153\/revisions\/2155"}],"wp:attachment":[{"href":"https:\/\/www.kuki.idv.tw\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2153"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.kuki.idv.tw\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2153"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.kuki.idv.tw\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2153"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}