我有一些拍照代码,可在Android 2.1和2.2中使用。
但是这些代码在Android 2.3上无法使用。
在花了一些时间解决这个徒劳的问题之后,我想在这里寻求帮助。

我的拍照流程如下:

创建一个类Camlayer扩展SurfaceView

public class CamLayer extends SurfaceView implements SurfaceHolder.Callback {
    private void init(Context context){
        // Install a SurfaceHolder.Callback so we get notified when the
        // underlying surface is created and destroyed.
        mHolder = getHolder();
        mHolder.addCallback(this);
        mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        mCamera = Camera.open();
    }

    public CamLayer(Context context) {
        super(context);
        init(context);
    }

    public CamLayer(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context);
    }

    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        Log.i(TAG+".surfaceChanged", "being called!");
        Log.i(TAG+".surfaceChanged", "w="+w);
        Log.i(TAG+".surfaceChanged", "h="+h);
        if (isPreviewRunning) {
            mCamera.stopPreview();
        }

        try {
            mCamera.setPreviewDisplay(holder);
            mCamera.setPreviewCallback(mPreviewCallback);
        } catch (IOException e) {
            Log.e(TAG+".surfaceCreated", "mCamera.setPreviewDisplay(holder);");
        }

        Camera.Parameters p = mCamera.getParameters();
        setOptimalSize(p, w, h, SIZEOFPREVIEW);
        setOptimalSize(p, w, h, SIZEOFPICTURE);
        mCamera.setParameters(p);

        mCamera.startPreview();
        isPreviewRunning = true;
    }

    public void takePicture(){
        Log.i(TAG+".takePicture", "being called!");
        mCamera.takePicture(null, null, mPictureCallback);
        Log.i(TAG+".takePicture", "call ended!");
    }
}
CamLayer.takePicture()将由外部类调用以启动。

问题在于,在Android 2.3.3上,takePicture将挂起,因此发现了ANR问题。在/data/anr/traces.txt中,找到以下内容。如您所见,native_takePicture从不返回。

DALVIK线程:
(mutexes: tll=0 tsl=0 tscl=0 ghl=0 hwl=0 hwll=0)
"main" prio=5 tid=1 NATIVE

  | group="main" sCount=1 dsCount=0 obj=0x40022170 self=0xce68

  | sysTid=2411 nice=0 sched=0/0 cgrp=default handle=-1345006464

  at android.hardware.Camera.native_takePicture(Native Method)

  at android.hardware.Camera.takePicture(Camera.java:746)

  at android.hardware.Camera.takePicture(Camera.java:710)

  at oms.cj.tube.camera.CamLayer.takePicture(CamLayer.java:256)

  at oms.cj.tube.camera.DefineColor.takePicture(DefineColor.java:61)

  at oms.cj.tube.camera.DefineColor.onKeyUp(DefineColor.java:71)

  at android.view.KeyEvent.dispatch(KeyEvent.java:1280)

  at android.app.Activity.dispatchKeyEvent(Activity.java:2078)

  at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:16
66)
  at android.view.ViewRoot.deliverKeyEventToViewHierarchy(ViewRoot.java:2571)

  at android.view.ViewRoot.handleFinishedEvent(ViewRoot.java:2546)

  at android.view.ViewRoot.handleMessage(ViewRoot.java:1878)

  at android.os.Handler.dispatchMessage(Handler.java:99)

  at android.os.Looper.loop(Looper.java:123)

  at android.app.ActivityThread.main(ActivityThread.java:3691)

  at java.lang.reflect.Method.invokeNative(Native Method)

  at java.lang.reflect.Method.invoke(Method.java:507)

  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:841)

  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:599)

  at dalvik.system.NativeStart.main(Native Method)

有人有同样的问题吗?知道如何解决吗?

最佳答案

我还观察到mCamera.takePicture(null,null,handler)卡住。我尝试在调用takePicture()之前清除预览处理程序:mCamera.setPreviewCallback(null),它现在可以工作。

10-08 15:10