我正在使用相机预览在水面视图中加载相机。但是当它在表面添加一个视图时,它会闪烁一个黑色屏幕一秒钟。如何避免这一个。下面是我的活动和相机预览课程
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.qr_code);
//mCamera = getCameraInstance();
qrCodeButton=(ImageButton) findViewById(R.id.qrcode_button);
settingsButton=(ImageButton) findViewById(R.id.settings_button);
mapLocationButton=(ImageButton) findViewById(R.id.location_button);
backButton=(ImageButton) findViewById(R.id.back_button);
iconButton=(ImageButton) findViewById(R.id.icon_button);
preview = (FrameLayout)findViewById(R.id.cameraPreview);
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
autoFocusHandler = new Handler();
releaseCamera();
mCamera = getCameraInstance();
scanner = new ImageScanner();
scanner.setConfig(0, Config.X_DENSITY, 3);
scanner.setConfig(0, Config.Y_DENSITY, 3);
if(mCamera!=null)
{
mPreview = new CameraPreview(getApplicationContext(), mCamera, previewCb, autoFocusCB);
// FrameLayout preview = (FrameLayout)rootView.findViewById(R.id.cameraPreview);
preview.addView(mPreview);
v = new ImageView(getApplicationContext());
// RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
//v.setLayoutParams(layoutParams);
v.setImageResource(R.drawable.qrscanbg2);
preview.addView(v);
//scannedResult(barcodeScanned);
if (barcodeScanned) {
barcodeScanned = false;
//scanText.setText("Scanning...");
mCamera.setPreviewCallback(previewCb);
mCamera.startPreview();
previewing = true;
mCamera.autoFocus(autoFocusCB);
}
}
else
{
Toast.makeText(getApplicationContext(), "Failed to Initialise camera", Toast.LENGTH_SHORT).show();
}
}
}, 1000);
}
这是我的相机预览课程
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
private SurfaceHolder mHolder;
private Camera mCamera;
private PreviewCallback previewCallback;
private AutoFocusCallback autoFocusCallback;
List<Size> mSupportedPreviewSizes;
public CameraPreview(Context context, Camera camera,
PreviewCallback previewCb,
AutoFocusCallback autoFocusCb) {
super(context);
mCamera = camera;
previewCallback = previewCb;
autoFocusCallback = autoFocusCb;
/*
* Set camera to continuous focus if supported, otherwise use
* software auto-focus. Only works for API level >=9.
*/
/*
Camera.Parameters parameters = camera.getParameters();
for (String f : parameters.getSupportedFocusModes()) {
if (f == Parameters.FOCUS_MODE_CONTINUOUS_PICTURE) {
mCamera.setFocusMode(Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);
autoFocusCallback = null;
break;
}
}
*/
// Install a SurfaceHolder.Callback so we get notified when the
// underlying surface is created and destroyed.
mHolder = getHolder();
mHolder.addCallback(this);
// deprecated setting, but required on Android versions prior to 3.0
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
public void setCamera(Camera camera) {
mCamera = camera;
if (mCamera != null) {
mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
requestLayout();
}
}
public void surfaceCreated(SurfaceHolder holder) {
// The Surface has been created, now tell the camera where to draw the preview.
try {
mCamera.setPreviewDisplay(holder);
} catch (IOException e) {
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
// Camera preview released in activity
}
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
/*
* If your preview can change or rotate, take care of those events here.
* Make sure to stop the preview before resizing or reformatting it.
*/
if (mHolder.getSurface() == null){
// preview surface does not exist
return;
}
// stop preview before making changes
try {
mCamera.stopPreview();
} catch (Exception e){
// ignore: tried to stop a non-existent preview
}
try {
// Hard code camera surface rotation 90 degs to match Activity view in portrait
mCamera.setDisplayOrientation(90);
mCamera.setPreviewDisplay(mHolder);
mCamera.setPreviewCallback(previewCallback);
mCamera.startPreview();
mCamera.autoFocus(autoFocusCallback);
} catch (Exception e){
// Log.d("DBG", "Error starting camera preview: " + e.getMessage());
}
}
}
答案 0 :(得分:0)
显然,将SurfaceView动态添加到没有SurfaceView刷新整个窗口的活动中。检查下面的答案。 https://stackoverflow.com/a/12636285/1705641