在android中camera.setParameters失败
我已经在我的应用程序中包含了相机function。 我也推出了在市场上的应用程序。 我从其中一个用户那里得到一个错误信息，他打开相机时出现错误。
我已经在2.1上testing了该设备上的应用程序。 我从用户得到的错误是使用nexus之一将主要运行2.2 …这是我收到的logcat错误…
java.lang.RuntimeException: setParameters failed at android.hardware.Camera.native_setParameters(Native Method) at android.hardware.Camera.setParameters(Camera.java:647) at com.CameraApp.Preview.surfaceChanged(Preview.java:67) at android.view.SurfaceView.updateWindow(SurfaceView.java:538) at android.view.SurfaceView.dispatchDraw(SurfaceView.java:339) at android.view.ViewGroup.drawChild(ViewGroup.java:1638) at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1367) at android.view.ViewGroup.drawChild(ViewGroup.java:1638) at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1367) at android.view.ViewGroup.drawChild(ViewGroup.java:1638) at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1367) at android.view.View.draw(View.java:6743) at android.widget.FrameLayout.draw(FrameLayout.java:352) at android.view.ViewGroup.drawChild(ViewGroup.java:1640) at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1367) at android.view.View.draw(View.java:6743) at android.widget.FrameLayout.draw(FrameLayout.java:352) at com.android.internal.policy.impl.PhoneWindow$DecorView.draw(PhoneWindow.java:1842) at android.view.ViewRoot.draw(ViewRoot.java:1407) at android.view.ViewRoot.performTraversals(ViewRoot.java:1163) at android.view.ViewRoot.handleMessage(ViewRoot.java:1727) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:123) at android.app.ActivityThread.main(ActivityThread.java:4627) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:521) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626) at dalvik.system.NativeStart.main(Native Method) 我在2.2模拟器上运行应用程序也检查它。 但它工作正常。 任何人都可以告诉我为什么错误发生？
这是我在评论中提到的那个class级：
class Preview extends SurfaceView implements SurfaceHolder.Callback { private static final String TAG = "Preview"; SurfaceHolder mHolder; public Camera camera; Preview(Context context) { super(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); } public void surfaceCreated(SurfaceHolder holder) { // The Surface has been created, acquire the camera and tell it where // to draw. camera = Camera.open(); try { camera.setPreviewDisplay(holder); } catch (IOException exception) { camera.release(); camera = null; // TODO: add more exception handling logic here } } public void surfaceDestroyed(SurfaceHolder holder) { // Surface will be destroyed when we return, so stop the preview. // Because the CameraDevice object is not a shared resource, it's very // important to release it when the activity is paused. camera.stopPreview(); camera.release(); camera = null; } public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) { // Now that the size is known, set up the camera parameters and begin // the preview. Camera.Parameters parameters = camera.getParameters(); parameters.setPreviewSize(w, h); camera.setParameters(parameters); camera.startPreview(); } @Override public void draw(Canvas canvas) { super.draw(canvas); Paint p= new Paint(Color.RED); Log.d(TAG,"draw"); canvas.drawText("PREVIEW", canvas.getWidth()/2, canvas.getHeight()/2, p ); } }
这是失败的，因为不是所有的设备支持任意的预览大小。 显然有些做，但你不能依靠它。 在你的surfaceChanged方法中，你需要做这样的事情：
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) { Camera.Parameters parameters = camera.getParameters(); List<Camera.Size> previewSizes = parameters.getSupportedPreviewSizes(); // You need to choose the most appropriate previewSize for your app Camera.Size previewSize = // .... select one of previewSizes here parameters.setPreviewSize(previewSize.width, previewSize.height); camera.setParameters(parameters); camera.startPreview(); }
你必须找出一个方法来扩展这个，以便你不会失去宽高比等。
这里是Android SDK文档的参考 。
