【发布时间】：2014-04-01 07:47:50
【问题描述】：
我正在使用 Xamarin.Android
我面临的问题是，当我们使用位图时，DalvikVM 堆大小会产生 OutOfMemoryException。
我已经实现了 IDisposable 模式来使用位图
using (var bmp = ImageResizer.DecodeSampledBitmapFromResource (Resources,
Resource.Drawable.exampleImage, Resources.DisplayMetrics.WidthPixels / 2,
(int)((Resources.DisplayMetrics.WidthPixels / 2) * _aspect)))
{
_btnFoo.SetImageBitmap (bmp);
bmp.Dispose ();
}
public static class ImageResizer
{
public static int CalculateInSampleSize(BitmapFactory.Options options,
int reqWidth, int reqHeight)
{
// Raw height and width of image
var height = (float)options.OutHeight;
var width = (float)options.OutWidth;
var inSampleSize = 1D;
if (height > reqHeight || width > reqWidth)
{
inSampleSize = width > height
? height/reqHeight
: width/reqWidth;
}
return (int) inSampleSize;
}
public static Bitmap DecodeSampledBitmapFromResource(Resources res, int resId,
int reqWidth, int reqHeight)
{
var options = new BitmapFactory.Options {
InJustDecodeBounds = true,
};
using (var dispose = BitmapFactory.DecodeResource(res, resId, options)) {
}
options.InSampleSize = CalculateInSampleSize(options, reqWidth, reqHeight);
options.InJustDecodeBounds = false;
return BitmapFactory.DecodeResource(res, resId, options);
}
}
实施此修复有助于解决一些问题，但是当使用第三个位图时，该应用程序仅在 Galaxy S4 上崩溃 在上述修复之前发生。
请参阅下面的堆栈跟踪以了解崩溃。
I/dalvikvm-heap( 312): Clamp target GC heap from 132.902MB to 128.000MB
D/dalvikvm( 312): GC_FOR_ALLOC freed 1852K, 4% free 126271K/130904K, paused 25ms, total 25ms
I/dalvikvm-heap( 312): Forcing collection of SoftReferences for 3134212-byte allocation
I/dalvikvm-heap( 312): Clamp target GC heap from 132.894MB to 128.000MB
D/dalvikvm( 312): GC_BEFORE_OOM freed 10K, 4% free 126261K/130904K, paused 29ms, total 29ms
E/dalvikvm-heap( 312): Out of memory on a 3134212-byte allocation.
I/dalvikvm( 312): "main" prio=5 tid=1 RUNNABLE
I/dalvikvm( 312): | group="main" sCount=0 dsCount=0 obj=0x413eeb38 self=0x413ddd78
I/dalvikvm( 312): | sysTid=312 nice=0 sched=0/0 cgrp=apps handle=1074968028
I/dalvikvm( 312): | state=R schedstat=( 0 0 0 ) utm=246 stm=59 core=2
I/dalvikvm( 312): at android.graphics.BitmapFactory.nativeDecodeAsset(Native Method)
I/dalvikvm( 312): at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:596)
I/dalvikvm( 312): at android.graphics.BitmapFactory.decodeResourceStream(BitmapFactory.java:444)
I/dalvikvm( 312): at android.graphics.BitmapFactory.decodeResource(BitmapFactory.java:472)
I/dalvikvm( 312): at guild.android.screens.CouponItemScreen.n_onTouch(Native Method)
I/dalvikvm( 312): at guild.android.screens.CouponItemScreen.onTouch(CouponItemScreen.java:47)
I/dalvikvm( 312): at android.view.View.dispatchTouchEvent(View.java:7495)
I/dalvikvm( 312): at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2291)
I/dalvikvm( 312): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1985)
I/dalvikvm( 312): at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2291)
I/dalvikvm( 312): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1985)
I/dalvikvm( 312): at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2291)
I/dalvikvm( 312): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1985)
I/dalvikvm( 312): at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2291)
I/dalvikvm( 312): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1985)
I/dalvikvm( 312): at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2291)
I/dalvikvm( 312): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1985)
I/dalvikvm( 312): at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:2240)
I/dalvikvm( 312): at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1535)
I/dalvikvm( 312): at android.app.Activity.dispatchTouchEvent(Activity.java:2466)
I/dalvikvm( 312): at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:2188)
I/dalvikvm( 312): at android.view.View.dispatchPointerEvent(View.java:7689)
I/dalvikvm( 312): at android.view.ViewRootImpl.deliverPointerEvent(ViewRootImpl.java:3794)
I/dalvikvm( 312): at android.view.ViewRootImpl.deliverInputEvent(ViewRootImpl.java:3678)
I/dalvikvm( 312): at android.view.ViewRootImpl.doProcessInputEvents(ViewRootImpl.java:4916)
I/dalvikvm( 312): at android.view.ViewRootImpl.enqueueInputEvent(ViewRootImpl.java:4895)
I/dalvikvm( 312): at android.view.ViewRootImpl$WindowInputEventReceiver.onInputEvent(ViewRootImpl.java:4993)
I/dalvikvm( 312): at android.view.InputEventReceiver.dispatchInputEvent(InputEventReceiver.java:185)
I/dalvikvm( 312): at android.os.MessageQueue.nativePollOnce(Native Method)
I/dalvikvm( 312): at android.os.MessageQueue.next(MessageQueue.java:125)
I/dalvikvm( 312): at android.os.Looper.loop(Looper.java:124)
I/dalvikvm( 312): at android.app.ActivityThread.main(ActivityThread.java:5279)
I/dalvikvm( 312): at java.lang.reflect.Method.invokeNative(Native Method)
I/dalvikvm( 312): at java.lang.reflect.Method.invoke(Method.java:511)
I/dalvikvm( 312): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1102)
I/dalvikvm( 312): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:869)
I/dalvikvm( 312): at dalvik.system.NativeStart.main(Native Method)
I/dalvikvm( 312):
D/skia ( 312): --- allocation failed for scaled bitmap
D/dalvikvm(15696): GC_CONCURRENT freed 2085K, 39% free 14681K/23884K, paused 2ms+13ms, total 40ms
【问题讨论】：
标签： android bitmap garbage-collection out-of-memory xamarin