1.?eclipse的Device中不顯示手機

在eclipse中連接不上手機,出現adb server didn't ACK? fail to start daemon 錯誤.

出現這種原因是因為adb所使用的5037端口被占用了.

使用adb kill-server 關閉adb服務 , 使用adb start-server開啟adb命令 ; 如果5037端口被占用則會出現啟動失敗, 報出上述錯誤;

查看哪些進程占用了端口 :?netstat -ano | findstr "5037" 會出現下面的結果

G:\Documents and Settings\Administrator>netstat -ano | findstr "5037"TCP 127.0.0.1:1939 127.0.0.1:5037 ESTABLISHED 5748TCP 127.0.0.1:1978 127.0.0.1:5037 ESTABLISHED 3000TCP 127.0.0.1:5037 0.0.0.0:0 LISTENING 5748TCP 127.0.0.1:5037 127.0.0.1:1939 ESTABLISHED 5748TCP 127.0.0.1:5037 127.0.0.1:1977 CLOSE_WAIT 5748TCP 127.0.0.1:5037 127.0.0.1:1978 ESTABLISHED 5748

可以看到 5748 3000 兩個進程占用了5037端口.

打開進程管理器, 點擊查看,選擇列,將PID進程標示符勾選上,然后根據pid終止相應的進程.

這兩個進程分別是豌豆莢 和 QQ , 同時將adb.exe 和 tadb.exe 進程干掉.

此時執行 adb start-server 命令即可啟動adb服務 , 之后啟動就會啟動成功.

2.?java.lang.OutOfMemoryError: thread creation failed 錯誤

10-17 09:51:58.830: E/AndroidRuntime(15695): FATAL EXCEPTION: Thread-316 10-17 09:51:58.830: E/AndroidRuntime(15695): java.lang.OutOfMemoryError: thread creation failed 10-17 09:51:58.830: E/AndroidRuntime(15695): at java.lang.VMThread.create(Native Method) 10-17 09:51:58.830: E/AndroidRuntime(15695): at java.lang.Thread.start(Thread.java:1050) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.alarm.AlarmPlayer.enqueue(AlarmPlayer.java:201) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.alarm.AlarmPlayer.resume(AlarmPlayer.java:192) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.director.MpmDirector.filterMpmHealthData(MpmDirector.java:270) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.director.MpmDirector.onHealthDataDecoded(MpmDirector.java:72) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.decoder.BaseDecoder.notifyAllDataDecodedListener(BaseDecoder.java:89) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.decoder.MpmEcgDecoder.caculateEcgResult(MpmEcgDecoder.java:394) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.decoder.MpmEcgDecoder.casulateResult(MpmEcgDecoder.java:269) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.decoder.MpmEcgDecoder.processBigPackageOfEcgData(MpmEcgDecoder.java:100) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.decoder.MpmEcgDecoder.processData(MpmEcgDecoder.java:87) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.decoder.MpmDecoder.operator(MpmDecoder.java:135) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.BqfjApplication$2.receiveData(BqfjApplication.java:148) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.bluetooth.BqfjBluetoothManager.notifyReceivers(BqfjBluetoothManager.java:281) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.bluetooth.BqfjConnectionManager$DataPump.run(BqfjConnectionManager.java:397) 10-17 09:51:58.830: E/AndroidRuntime(15695): at com.ivt.mHealth.util.ReusableThread.run(ReusableThread.java:85) 10-17 09:51:58.830: E/AndroidRuntime(15695): at java.lang.Thread.run(Thread.java:856) 10-17 09:51:58.920: V/StagefrightPlayer(1875): isPlaying 10-17 09:51:58.920: V/MediaPlayerService(1875): [20] isPlaying: 0 10-17 09:51:58.920: V/MediaPlayer(15695): isPlaying: 0 10-17 09:51:58.920: V/MediaPlayer-JNI(15695): isPlaying: 0 10-17 09:51:58.925: D/dalvikvm(2219): GC_FOR_ALLOC freed 1595K, 30% free 26891K/37895K, paused 77ms, total 77ms 10-17 09:51:58.930: E/SQLiteLog(15695): (14) cannot open file at line 30241 of [00bb9c9ce4] 10-17 09:51:58.930: E/SQLiteLog(15695): (14) os_unix.c:30241: (2) open(/NotificationPermissions.db) - 10-17 09:51:58.930: D/STATUSBAR-NetworkController(2441): refreshSignalCluster: data=-1 bt=false

開發中遇到了上述錯誤 , 后來發現是 使用了TraceView導致的

不知道在代碼的什么地方添加了TraceView的相關代碼 , 去掉之后 , 就好了

我在Activity中的onCreate()方法中添加了 :?

Debug.startMethodTracing();
在onDestroy()方法中添加了 :

Debug.stopMethodTracing();
去掉了上述兩行代碼 , 就不會出現上述錯誤了 ;

3.?Call requires API level 8 (current min is 1)錯誤

導入了一個程序 , 每次運行之后都會出現該錯誤 .

點擊clean 錯誤就會消失 , 但是執行該錯誤的時候該錯誤就會重新出現 .?

這個錯誤需要在AndroidManifest.xml配置文件中修改 user-sdk 標簽

給user-sdk 添加一個android:minSdkVersion="8" 屬性

4.?奇怪的空指針異常

今天出現一個奇怪的錯誤, 很簡單空指針異常, 我只負責編碼, 不管編譯, 然后上傳到SVN上, 結果出了下面的錯誤 , 看了半天 , 木有看懂 :?

11-13 10:39:53.337: E/AndroidRuntime(11030): FATAL EXCEPTION: Thread-394 11-13 10:39:53.337: E/AndroidRuntime(11030): java.lang.NullPointerException 11-13 10:39:53.337: E/AndroidRuntime(11030): at com.ivt.mHealth.widget.aa.b(Unknown Source) 11-13 10:39:53.337: E/AndroidRuntime(11030): at com.ivt.mHealth.widget.DisplaySurfaceView.a(Unknown Source) 11-13 10:39:53.337: E/AndroidRuntime(11030): at com.ivt.mHealth.widget.ae.run(Unknown Source)
我一看 蒙了 , 這是什么錯誤 , 沒定義過這個類啊 , 后來才想起來 這是代碼混淆以后的效果 .?

有點無語 ... 想了半小時才反應過來?

我直接從SVN上down了一下代碼, 重新編譯下 , ╮(╯▽╰)╭ 撥云見日?

11-13 10:41:57.432: E/AndroidRuntime(11507): FATAL EXCEPTION: Thread-398 11-13 10:41:57.432: E/AndroidRuntime(11507): java.lang.NullPointerException 11-13 10:41:57.432: E/AndroidRuntime(11507): at com.ivt.mHealth.widget.BpmSurface.drawMpmBpm(BpmSurface.java:169) 11-13 10:41:57.432: E/AndroidRuntime(11507): at com.ivt.mHealth.widget.BpmSurface.drawToSurfaceView(BpmSurface.java:109) 11-13 10:41:57.432: E/AndroidRuntime(11507): at com.ivt.mHealth.widget.DisplaySurfaceView.drawToSurface(DisplaySurfaceView.java:183) 11-13 10:41:57.432: E/AndroidRuntime(11507): at com.ivt.mHealth.widget.DisplaySurfaceView.access$1(DisplaySurfaceView.java:178) 11-13 10:41:57.432: E/AndroidRuntime(11507): at com.ivt.mHealth.widget.DisplaySurfaceView$RenderThread.run(DisplaySurfaceView.java:144)

以后千萬不要看編譯出來的產品的log , 都是混效過的 ........?

這是少上傳了一行代碼到SVN上啊 ...... 淚奔 .... 半小時就這么浪費了

5. 內存溢出錯誤?

adb shell dumpsys meminfo com.ivt.mHealth

08-12 12:48:52.798: I/dalvikvm-heap(15260): Clamp target GC heap from 64.996MB to 64.000MB 08-12 12:48:52.798: D/dalvikvm(15260): GC_FOR_ALLOC freed 1K, 3% free 63863K/65543K, paused 190ms, total 190ms 08-12 12:48:52.798: I/dalvikvm-heap(15260): Forcing collection of SoftReferences for 21473-byte allocation 08-12 12:48:52.988: I/dalvikvm-heap(15260): Clamp target GC heap from 64.987MB to 64.000MB 08-12 12:48:52.988: D/dalvikvm(15260): GC_BEFORE_OOM freed 9K, 3% free 63853K/65543K, paused 186ms, total 186ms 08-12 12:48:52.988: E/dalvikvm-heap(15260): Out of memory on a 21473-byte allocation. 08-12 12:48:52.988: I/dalvikvm(15260): "main" prio=5 tid=1 RUNNABLE 08-12 12:48:52.988: I/dalvikvm(15260): | group="main" sCount=0 dsCount=0 obj=0x40efd508 self=0x40d62778 08-12 12:48:52.988: I/dalvikvm(15260): | sysTid=15260 nice=0 sched=0/0 cgrp=apps handle=1074577200 08-12 12:48:52.988: I/dalvikvm(15260): | schedstat=( 21710980394 3466435126 36123 ) utm=1846 stm=324 core=1 08-12 12:48:52.988: I/dalvikvm(15260): at com.ivt.mHealth.util.ByteArrayBuffer.expand(ByteArrayBuffer.java:~28) 08-12 12:48:52.988: I/dalvikvm(15260): at com.ivt.mHealth.util.ByteArrayBuffer.append(ByteArrayBuffer.java:62) 08-12 12:48:52.988: I/dalvikvm(15260): at com.ivt.mHealth.util.BqfjHttpHeaderPacker.packHttpHeader(BqfjHttpHeaderPacker.java:185) 08-12 12:48:52.988: I/dalvikvm(15260): at com.ivt.mHealth.datacommunication.impl.BqfjSendRTMpmDataMessageHandler$PacketTransController.sendPacket(BqfjSendRTMpmDataMessageHandler.java:770) 08-12 12:48:52.988: I/dalvikvm(15260): at com.ivt.mHealth.datacommunication.impl.BqfjSendRTMpmDataMessageHandler$PacketTransController.onPacketReceived(BqfjSendRTMpmDataMessageHandler.java:814) 08-12 12:48:52.988: I/dalvikvm(15260): at com.ivt.mHealth.datacommunication.impl.BqfjSendRTMpmDataMessageHandler$1.handleMessage(BqfjSendRTMpmDataMessageHandler.java:526) 08-12 12:48:52.988: I/dalvikvm(15260): at android.os.Handler.dispatchMessage(Handler.java:99) 08-12 12:48:52.988: I/dalvikvm(15260): at android.os.Looper.loop(Looper.java:137) 08-12 12:48:52.988: I/dalvikvm(15260): at android.app.ActivityThread.main(ActivityThread.java:4921) 08-12 12:48:52.988: I/dalvikvm(15260): at java.lang.reflect.Method.invokeNative(Native Method) 08-12 12:48:52.988: I/dalvikvm(15260): at java.lang.reflect.Method.invoke(Method.java:511) 08-12 12:48:52.988: I/dalvikvm(15260): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1038) 08-12 12:48:52.988: I/dalvikvm(15260): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:805) 08-12 12:48:52.988: I/dalvikvm(15260): at dalvik.system.NativeStart.main(Native Method) 08-12 12:48:52.988: D/AndroidRuntime(15260): Shutting down VM 08-12 12:48:52.988: W/dalvikvm(15260): threadid=1: thread exiting with uncaught exception (group=0x40efc2a0) 08-12 12:48:52.993: V/BluetoothSocket.cpp(15260): readNative 08-12 12:48:52.993: E/AndroidRuntime(15260): FATAL EXCEPTION: main 08-12 12:48:52.993: E/AndroidRuntime(15260): java.lang.OutOfMemoryError 08-12 12:48:52.993: E/AndroidRuntime(15260): at com.ivt.mHealth.util.ByteArrayBuffer.expand(ByteArrayBuffer.java:28) 08-12 12:48:52.993: E/AndroidRuntime(15260): at com.ivt.mHealth.util.ByteArrayBuffer.append(ByteArrayBuffer.java:62) 08-12 12:48:52.993: E/AndroidRuntime(15260): at com.ivt.mHealth.util.BqfjHttpHeaderPacker.packHttpHeader(BqfjHttpHeaderPacker.java:185) 08-12 12:48:52.993: E/AndroidRuntime(15260): at com.ivt.mHealth.datacommunication.impl.BqfjSendRTMpmDataMessageHandler$PacketTransController.sendPacket(BqfjSendRTMpmDataMessageHandler.java:770) 08-12 12:48:52.993: E/AndroidRuntime(15260): at com.ivt.mHealth.datacommunication.impl.BqfjSendRTMpmDataMessageHandler$PacketTransController.onPacketReceived(BqfjSendRTMpmDataMessageHandler.java:814) 08-12 12:48:52.993: E/AndroidRuntime(15260): at com.ivt.mHealth.datacommunication.impl.BqfjSendRTMpmDataMessageHandler$1.handleMessage(BqfjSendRTMpmDataMessageHandler.java:526) 08-12 12:48:52.993: E/AndroidRuntime(15260): at android.os.Handler.dispatchMessage(Handler.java:99) 08-12 12:48:52.993: E/AndroidRuntime(15260): at android.os.Looper.loop(Looper.java:137) 08-12 12:48:52.993: E/AndroidRuntime(15260): at android.app.ActivityThread.main(ActivityThread.java:4921) 08-12 12:48:52.993: E/AndroidRuntime(15260): at java.lang.reflect.Method.invokeNative(Native Method) 08-12 12:48:52.993: E/AndroidRuntime(15260): at java.lang.reflect.Method.invoke(Method.java:511) 08-12 12:48:52.993: E/AndroidRuntime(15260): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1038) 08-12 12:48:52.993: E/AndroidRuntime(15260): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:805) 08-12 12:48:52.993: E/AndroidRuntime(15260): at dalvik.system.NativeStart.main(Native Method) 08-12 12:48:53.013: E/android.os.Debug(2224): !@Dumpstate > dumpstate -k -t -z -d -o /data/log/dumpstate_app_error 08-12 12:48:53.018: I/dumpstate(308): begin

---

1.什么是 OutOfMemoryError：

? ?官方引用：?Thrown when a request for memory is made that can not be satisfied using the available platform resources. Such a request may be made by both the running application or by an internal function of the VM.
? ?通俗的講：就是在請求一塊內存的時候，當前可用資源不夠用來請求時拋出的一種錯誤。我們知道，每個 android 程序就是一個獨立 dalvik vm 實例，每個實例限制了最大內存占用，如果超過了這個限制，系統就會拋出這個錯誤。所以跟整個設備的剩余內存沒太大關系，當然如果設備剩余內存都不足以再運行一個程序時，系統就會選擇 kill 部分程序以確保有足夠內存運行其他程序。

?

2.android 內存組成：

? ?android 內存由 dalvik 和 native 2部分組成，dalvik 也就是 java 堆，創建的對象就是在這里分配的，而 native 是通過 c/c++ 方式申請的內存，Bitmap 就是以一種方式分配的（android3.0 以后，系統默認是通過 dalvik 分配的）。當然無論以何種方式分配，2部分加起來不能超過 android 對單個程序的內存限制。

?

3.內存限制大小：

1 ActivityManager activityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE); 2 activityManager.getMemoryClass();

?以上方法會返回以 M 為單位的數字，可能在不同的平臺或者設備上值都不太一樣，比如：HTC G7 默認 24M，Galaxy 36M，emulator-2.3 24M，等等。

?

4.程序實際占用：

? 以一個簡單的 android 程序為例，該程序是用 eclipse adt 自動生成的最簡單的一個 android 項目，只有1個 activity 和 adt 自動生成的 res 目錄，測試環境：emulator-2.3.3
? 啟動該程序，命令行運行：

?

adb shell dumpsys meminfo com.mem.demo

?

? 執行結果：

?

Applications Memory Usage (kB):Uptime: 1195344 Realtime: 1195344** MEMINFO in pid 333 [com.mem.demo] **native dalvik other total--------------------------------------------------------| size: 3968 5379 N/A 9347 || || allocated: 3964 2649 N/A 6613 |--------------------------------------------------------free: 3 2730 N/A 2733(Pss): 553 449 2516 3518(shared dirty): 2272 1868 6648 10788(priv dirty): 420 32 1140 1592ObjectsViews: 0 ViewRoots: 0AppContexts: 0 Activities: 0Assets: 2 AssetManagers: 2Local Binders: 5 Proxy Binders: 10Death Recipients: 0OpenSSL Sockets: 0SQLheap: 0 MEMORY_USED: 0PAGECACHE_OVERFLOW: 0 MALLOC_SIZE: 0Asset Allocationszip:/data/app/com.mem.demo-1.apk:/resources.arsc: 1K

?

從上面被框出來的部分可以看出，一個最簡單的 android 程序在啟動后都有 6m 左右內存的占用（上面是 6613kb）。那這 6m 的內存除了該 android 自己的資源和類之外，其他的還有什么呢：

簡單說：在初始化的時候會 preload 一些東西，這些就包括 classes 和系統資源，就是系統的一些布局啊，圖片啊，等等，在 android 完成啟動以后，這部分就通過內存共享的方式共享給其他程序，可以讓其他程序可以調用這部分資源，代碼可以參考：http://goo.gl/EKvCV，android 整個啟動流程可以參考：http://goo.gl/K36Lr?。

?

5.發生 OOM ：

?為了制造 OOM，我們對上面最簡單的程序進行了改寫：

?

12345678910111213141516171819202122

package?com.mem.demo;import?android.app.Activity;import?android.graphics.Bitmap;import?android.graphics.BitmapFactory;import?android.os.Bundle;public?class?DemoActivityextends?Activity {????Bitmap map1, map2, map3, map4;????/** Called when the activity is first created. */????@Override????public?void?onCreate(Bundle savedInstanceState) {????????super.onCreate(savedInstanceState);????????setContentView(R.layout.main);????????map1 = BitmapFactory.decodeResource(getResources(), R.drawable.big1);????????map2 = BitmapFactory.decodeResource(getResources(), R.drawable.big2);????????map3 = BitmapFactory.decodeResource(getResources(), R.drawable.big3);????????map4 = BitmapFactory.decodeResource(getResources(), R.drawable.big4);????}}

?

其中：big1 到 big4 都是 1600*900 分辨率的圖片，放在 drawbable-hdpi 文件夾下面，啟動程序，發生了 OOM：

?

05-08 07:44:44.372: E/dalvikvm-heap(386): 5760000-byte external allocation too large for this process. 05-08 07:44:44.412: I/dalvikvm-heap(386): Clamp target GC heap from 25.099MB to 24.000MB 05-08 07:44:44.412: E/GraphicsJNI(386): VM won't let us allocate 5760000 bytes 05-08 07:44:44.412: D/dalvikvm(386): GC_FOR_MALLOC freed 0K, 53% free 2548K/5379K, external 18500K/20548K, paused 36ms 05-08 07:44:44.422: D/skia(386): --- decoder->decode returned false 05-08 07:44:44.422: D/AndroidRuntime(386): Shutting down VM 05-08 07:44:44.432: W/dalvikvm(386): threadid=1: thread exiting with uncaught exception (group=0x40015560) 05-08 07:44:44.442: E/AndroidRuntime(386): FATAL EXCEPTION: main 05-08 07:44:44.442: E/AndroidRuntime(386): java.lang.OutOfMemoryError: bitmap size exceeds VM budget 05-08 07:44:44.442: E/AndroidRuntime(386): at android.graphics.BitmapFactory.nativeDecodeAsset(Native Method) 05-08 07:44:44.442: E/AndroidRuntime(386): at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:460) 05-08 07:44:44.442: E/AndroidRuntime(386): at android.graphics.BitmapFactory.decodeResourceStream(BitmapFactory.java:336) 05-08 07:44:44.442: E/AndroidRuntime(386): at android.graphics.BitmapFactory.decodeResource(BitmapFactory.java:359) 05-08 07:44:44.442: E/AndroidRuntime(386): at android.graphics.BitmapFactory.decodeResource(BitmapFactory.java:385) 05-08 07:44:44.442: E/AndroidRuntime(386): at com.mem.demo.DemoActivity.onCreate(DemoActivity.java:20) 05-08 07:44:44.442: E/AndroidRuntime(386): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047) 05-08 07:44:44.442: E/AndroidRuntime(386): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611) 05-08 07:44:44.442: E/AndroidRuntime(386): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663) 05-08 07:44:44.442: E/AndroidRuntime(386): at android.app.ActivityThread.access$1500(ActivityThread.java:117) 05-08 07:44:44.442: E/AndroidRuntime(386): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931) 05-08 07:44:44.442: E/AndroidRuntime(386): at android.os.Handler.dispatchMessage(Handler.java:99) 05-08 07:44:44.442: E/AndroidRuntime(386): at android.os.Looper.loop(Looper.java:123) 05-08 07:44:44.442: E/AndroidRuntime(386): at android.app.ActivityThread.main(ActivityThread.java:3683) 05-08 07:44:44.442: E/AndroidRuntime(386): at java.lang.reflect.Method.invokeNative(Native Method) 05-08 07:44:44.442: E/AndroidRuntime(386): at java.lang.reflect.Method.invoke(Method.java:507) 05-08 07:44:44.442: E/AndroidRuntime(386): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) 05-08 07:44:44.442: E/AndroidRuntime(386): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) 05-08 07:44:44.442: E/AndroidRuntime(386): at dalvik.system.NativeStart.main(Native Method)

?

從日志上看，內存不足發生在 decode big4 這個圖片的時候，我們對內存情況進行打印：

?

Applications Memory Usage (kB): Uptime: 958383 Realtime: 958383** MEMINFO in pid 386 [com.mem.demo] **native dalvik other totalsize: 25144 5379 N/A 30523allocated: 20799 2614 N/A 23413free: 60 2765 N/A 2825(Pss): 494 426 18494 19414(shared dirty): 2288 1876 5292 9456(priv dirty): 360 28 17836 18224

?

從內存打印情況看出，當前已經分配了 23m 左右內存，同時結合 logcat 錯誤日志，big4 這個圖片需要申請 5760000byte，即:5.76m 的內存，加起來就是 29m 左右內存，我們測試環境是 emulator2.3.3 默認是
24m，內存不足以申請這么多，所以拋出了OOM。

那為什么區區3，4張圖片就會讓 android 程序內存不足？?
設備限制是一方面，像上面第3點說的，每個 android 設備的內存限制不一樣，這個程序在模擬器上會有問題，在其他設備上，比如：galaxy 就不會有問題。最主要的還是跟圖片所占內存有關系，那么一張圖片到底
占用多少內存呢，java 沒有 c 的 sizeof() 函數，無法準確去量化這個數值，但是可以有粗略的計算方法：

?

寬 * 高 * 每個像素所占的 bytes

?

寬度和高度這個很容易獲得，那每個像素所占的 bytes 呢，這個主要取決于 decode 圖片的方式：

?

Bitmap.Config ALPHA_8 Each pixel is stored as a single translucency (alpha) channel. Bitmap.Config ARGB_4444 This field is deprecated. Because of the poor quality of this configuration, it is advised to use ARGB_8888 instead. Bitmap.Config ARGB_8888 Each pixel is stored on 4 bytes. Bitmap.Config RGB_565 Each pixel is stored on 2 bytes and only the RGB channels are encoded: red is stored with 5 bits of precision (32 possible values), green is store d with 6 bits of precision (64 possible values) and blue is stored with 5 bits of precision.

?

以上是官方文檔對?Bitmap.Config?類的描述，所以，如果以 ARGB_8888 的方式 decode，那個每個像素占用4個 bytes，而如果用 RGB_565 就占用2個 bytes。
我們計算一下，在 2.3 以后，程序自帶的圖片資源，都默認以 ARGB_8888 的方式，而在此以之前是以 RGB_565 的方式（不確定，待驗證），所以顏色會有損耗，典型的就是如果有漸變色的話，會出現光圈。
所以，計算如下：

?

1600 * 900 * 4 = 5760000

?

?這個 5760000 也就是上面 logcat 錯誤日志里面所提到的申請數字，當然在實際用命令打印出的內存情況上看，比這個數字要大，是因為這只是圖片像素的內存，還有一些屬性，變量和類本身沒有計算在內。

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