切换摄像头的Android时相机preVIEW死机？ [英] Android camera preview freezes when switching cameras?
本文介绍了切换摄像头的Android时相机preVIEW死机？的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我写一个自定义的相机我的应用程序。它与无论是前面或后面的摄像头打开活动时找工作，但我真的在里面活动切换相机挣扎。
I am writing a custom camera for my app. It's working find when opening the activity with either of the back or front cameras, but I'm really struggling with switching cameras inside the activity.
当我点击切换拍照键，的preVIEW冻结并没有任何反应。我试图在有关相机和preVIEW其他问题提出的答案和提示，但没有任何工程。
When I tap the switching camera button, the preview freezes and nothing happens. I have tried the answers and tips suggested in other questions related to the camera and the preview, but nothing works.
下面是我的活动：
public class CameraActivity extends Activity implements SurfaceHolder.Callback {
//================================================================================
// Properties
//================================================================================
// Tag
private final String TAG = "CameraActivity";
// Camera and CameraPreview objects
private Camera mCamera;
// SurfaceHolder object
private SurfaceHolder mSurfaceHolder;
// private CameraPreview mPreview;
// ImageButtons
private ImageButton captureButton;
private ImageButton camSwitchButton;
// Picture previewLayout
FrameLayout previewLayout;
SurfaceView preview;
// Current camera is facing FRONT or BACK
private int currentCameraId = Camera.CameraInfo.CAMERA_FACING_FRONT;
// Picture taking callback
private Camera.PictureCallback mPictureCallback;
//================================================================================
// Methods
//================================================================================
@Override
public void onCreate(final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Activity with no notification bar
requestWindowFeature(Window.FEATURE_NO_TITLE);
// Set content view
setContentView(R.layout.activity_camera);
// Initialize activity and previews
InitActivity();
InitPreview();
// Set onClicks
}
/**
* Initialize activity views
*/
private void InitActivity() {
// Create an instance of Camera
mCamera = GetCameraInstance(currentCameraId);
// Set the SurfaceView
preview = (SurfaceView) findViewById(R.id.camera_preview);
mSurfaceHolder = preview.getHolder();
mSurfaceHolder.addCallback(this);
}
/**
* Initialize the camera preview
*/
private void InitPreview() {
if (mCamera != null) {
try {
mCamera.setPreviewDisplay(mSurfaceHolder);
} catch (IOException e) {
// log
}
mCamera.startPreview();
}
}
@Override
protected void onPause() {
super.onPause();
if (mCamera != null) {
mCamera.stopPreview();
mCamera.release(); // release the camera for other applications
// mCamera = null;
}
}
@Override
protected void onResume() {
super.onResume();
if (mCamera == null) {
InitActivity();
InitPreview();
}
}
/**
* Get camera instance
* @return Camera instance (null if doesn't exist)
*/
private Camera GetCameraInstance(int camid) {
Camera c = null;
try {
c = Camera.open(camid); // attempt to get a Camera instance
Camera.Parameters campar = c.getParameters();
// Set auto-focus
if (getPackageManager().hasSystemFeature("android.hardware.camera.autofocus")) {
campar.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);
}
c.setParameters(campar);
}
catch (Exception e){
// log
}
return c; // returns null if camera is unavailable
}
/**
* Switch the camera from front to back and vica verca
*/
private void SwitchCamera() {
if (mCamera != null) {
mCamera.stopPreview();
mCamera.release();
// mCamera = null;
}
//swap the id of the camera to be used
if (currentCameraId == Camera.CameraInfo.CAMERA_FACING_BACK) {
currentCameraId = Camera.CameraInfo.CAMERA_FACING_FRONT;
}
else currentCameraId = Camera.CameraInfo.CAMERA_FACING_FRONT;
// Remove the view and re-add it
ViewGroup rootView = (ViewGroup) preview.getParent();
rootView.removeView(previewLayout);
mCamera = GetCameraInstance(currentCameraId);
InitActivity();
}
@Override
public void surfaceCreated(SurfaceHolder surfaceHolder) {
Logger.Log(TAG, "SurfaceCreated");
InitPreview();
}
@Override
public void surfaceChanged(SurfaceHolder surfaceHolder, int format, int width, int height) {
// Return if no surface found
if (mSurfaceHolder.getSurface() == null) {
return;
}
// Start preview with new settings
Camera.Parameters params = mCamera.getParameters();
boolean isPortrait = IsPortrait();
// Configure the parameters (so the image is showing correctly)
ConfigureCameraParameters(params, isPortrait);
// Start preview
InitPreview();
}
@Override
public void surfaceDestroyed(SurfaceHolder surfaceHolder) {
if (mCamera != null) {
mCamera.stopPreview();
mCamera.release();
mCamera = null;
}
}
/**
* Configure the camer parameters
* @param cameraParams Camera parameters
* @param isPortrait Is the camera in portrait mode?
*/
protected void ConfigureCameraParameters(Camera.Parameters cameraParams, boolean isPortrait) {
int angle;
Display display = getWindowManager().getDefaultDisplay();
// Correct the orientation
switch (display.getRotation()) {
case Surface.ROTATION_0: // This is display orientation
angle = 90; // This is camera orientation
break;
case Surface.ROTATION_90:
angle = 0;
break;
case Surface.ROTATION_180:
angle = 270;
break;
case Surface.ROTATION_270:
angle = 180;
break;
default:
angle = 90;
break;
}
mCamera.setDisplayOrientation(angle);
mCamera.setParameters(cameraParams);
}
/**
* Check whether the camera is in portrait mode
* @return True|False
*/
private boolean IsPortrait() {
return (getResources().getConfiguration().orientation
== Configuration.ORIENTATION_PORTRAIT);
}
}
在清单权限：
<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />
<uses-feature android:name="android.hardware.camera.autofocus" />
我真的AP preciate，如果有人可以提供帮助。
I really appreciate it if someone could help.
推荐答案
您是pretty接近，你不需要摧毁你切换相机表面观每次，你只需要摧毁相机会话，然后使一定要重新挂钩相机回surfaceview所以它可以显示出来。我有一些麻烦您的前置后轮上的Razr面临最大的逻辑，所以我只是把它转换为1和0。
You are pretty close, you dont need to destroy the surface view everytime you switch the camera, you only need to destroy the camera session and then make sure you re hook up the camera back to the surfaceview so it can be displayed. I was having some trouble with your front facing rear facing logic on a Razr Max so I just switched it to 1 and 0.
private void SwitchCamera() {
if (mCamera != null) {
mCamera.stopPreview();
mCamera.release();
mCamera = null;
}
//swap the id of the camera to be used
if (currentCameraId == Camera.CameraInfo.CAMERA_FACING_FRONT) {
currentCameraId = 0;
} else {
currentCameraId = 1;
}
mCamera = GetCameraInstance(currentCameraId);
InitPreview();
}
这篇关于切换摄像头的Android时相机preVIEW死机？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
查看全文
