Android：覆盖 Android 相机预览

我正在使用相机 API 并调用相机。

我想在相机预览的顶部显示标题（用于品牌）。标题是 jpeg 图像。

是否可以？任何帮助表示赞赏。

提前致谢。

我的代码如下。

public class CameraActivity extends Activity {
    @Override
    protected void onPause() {

        super.onPause();
    }

    private static final int CAMERA_PIC_REQUEST = 2500;
    private Bitmap image2;
    private Bitmap bm;
    public static String imagepath;
    public static int x=1;
    private RdmsDbAdapter dbHelper;
    @Override



    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.header);
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
        //caling new incident
        if(IncidentFormActivity.incident_id == null || IncidentFormActivity.isDisable==true){
            //DBAdapter instance created and connection opened. 
            dbHelper = new RdmsDbAdapter(CameraActivity.this);
            dbHelper.open();

            //setting up flags
            NewIncidentHelper nih = new NewIncidentHelper();
            nih.setUpNewIncident();

            //setting up incident_id
            String Date= IncidentIdGenerator.getDate();
            String Time = IncidentIdGenerator.getTime();

            IncidentFormActivity.incident_id = IncidentIdGenerator.now("ddMMyyyyHHmmss");
            dbHelper.executeSQL("insert into incident values ('" + IncidentFormActivity.incident_id
                    + "', ' ', ' ', ' ', ' ', '"+Date+"', '0','0','0','0','0','0','0','0','0','"+Time+"')");
            dbHelper.close();
        }

        //calling camera
        Intent cameraIntent = new Intent(
                android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
        startActivityForResult(cameraIntent, CAMERA_PIC_REQUEST);


    }
    public String getPath(Uri uri) {
        String[] projection = { MediaStore.Images.Media.DATA };
        Cursor cursor = managedQuery(uri, projection, null, null, null);
        int column_index = cursor
                .getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
        cursor.moveToFirst();
        return cursor.getString(column_index);
    }

    //back key on phone pressed
    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        switch (keyCode) {
        case KeyEvent.KEYCODE_BACK:
            Intent i= new Intent(CameraActivity.this, IncidentFormActivity.class);
            startActivity(i);
            this.finish();

            break;

        default:
            break;
        }
        return super.onKeyDown(keyCode, event);
    }

    //handle response came from camera when the picture is taken.
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == CAMERA_PIC_REQUEST && resultCode == RESULT_OK) {
                final ImageView img = new ImageView(this);
                img.setLayoutParams(new LayoutParams(100, 100));
                image2 = (Bitmap) data.getExtras().get("data");
                img.setImageBitmap(image2);
                String incident_ID = IncidentFormActivity.incident_id;
                //l2.addView(img);
                    imagepath="/sdcard/RDMS/"+incident_ID+ x + ".png";
                File file = new File(imagepath);
                try {
                     bm = Bitmap.createScaledBitmap( image2,400, 300, true);
                    file.createNewFile();
                    FileOutputStream ostream = new FileOutputStream(file);
                    bm.compress(CompressFormat.PNG, 90, ostream);
                    ostream.close(); 
                    //Initialising db class and inserting values
                    dbHelper = new RdmsDbAdapter(CameraActivity.this);
                    dbHelper.open();
                    dbHelper.executeSQL("insert into files values ('"+imagepath+"', '"+IncidentFormActivity.incident_id+"')");
                    dbHelper.close();

                } catch (Exception e) {
                    e.printStackTrace();
                    Toast.makeText(getApplicationContext(),"yourfirst  error message is "
                                            + e.toString(), 1000).show();
                }
                x++;
                final AlertDialog.Builder alert = new AlertDialog.Builder(
                        CameraActivity.this);

                alert.setTitle(getString(R.string.anotherimage));
                alert.setCancelable(false);
                //alert.setMessage("Play or Delete the Video selected");
                //alert.setIcon(R.drawable.vid_red);
                alert.setPositiveButton(getString(R.string.yes), new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int id) {
                        Intent sendingpage = new Intent(CameraActivity.this, CameraActivity.class);
                          startActivity(sendingpage);

                    }
                });
                alert.setNegativeButton(getString(R.string.no),
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog, int id) {
                                Intent callback = new Intent (CameraActivity.this, IncidentFormActivity.class);
                                startActivity(callback);
                            }
                        });

                alert.show();


            }
            if(resultCode==RESULT_CANCELED)
            {

                AlertDialog.Builder builder = new AlertDialog.Builder(CameraActivity.this);

                builder.setMessage(getString(R.string.areuexit)).setCancelable(
                        false).setPositiveButton(getString(R.string.yes),
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog, int id) {
                                Intent i= new Intent(CameraActivity.this, IncidentFormActivity.class);
                                startActivity(i);
                                CameraActivity.this.finish();
                            }
                        }).setNegativeButton(getString(R.string.no),
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog, int id) {
                                dialog.cancel();
                                Intent i= new Intent(CameraActivity.this, CameraActivity.class);                            startActivity(i);
                                CameraActivity.this.finish();
                            }
                        });

                builder.show();



            }
        }
    }

您可以使用 SurfaceView 并创建一个将打开相机的 CustomView，并且您可以相应地在 xml 中调整其大小。下面是伪代码。

创建一个扩展 SurfaceView 的类并在其中打开相机

捕获预览.java

public class CapturePreview extends SurfaceView implements SurfaceHolder.Callback{

    public static Bitmap mBitmap;
    SurfaceHolder holder;
    static Camera mCamera;

    public CapturePreview(Context context, AttributeSet attrs) {
        super(context, attrs);

        holder = getHolder();
        holder.addCallback(this);
        holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width,int height) {

        Camera.Parameters parameters = mCamera.getParameters();
        parameters.getSupportedPreviewSizes();
        mCamera.setParameters(parameters);
        mCamera.startPreview();
    }
    @Override
    public void surfaceCreated(SurfaceHolder holder) {

        try {
            mCamera = Camera.open();
            mCamera.setPreviewDisplay(holder);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        mCamera.stopPreview();
        mCamera.release();
    }
    /***
     * 
     *  Take a picture and and convert it from bytes[] to Bitmap.
     *  
     */
    public static void takeAPicture(){  

        Camera.PictureCallback mPictureCallback = new PictureCallback() {
            @Override
            public void onPictureTaken(byte[] data, Camera camera) {

                BitmapFactory.Options options = new BitmapFactory.Options();
                mBitmap = BitmapFactory.decodeByteArray(data, 0, data.length, options);
            }
        };
        mCamera.takePicture(null, null, mPictureCallback);
    }
}

现在您必须在 xml 中包含使用 SurfaceView 创建的视图，如下所示

main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent">

  <FrameLayout 
  android:id="@+id/mySurfaceView"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content">

  <com.cam.CapturePreview 
  android:layout_width="fill_parent"
  android:layout_height="wrap_content">
  </com.cam.CapturePreview>

  </FrameLayout>

  <LinearLayout 
  android:layout_below="@id/mySurfaceView" 
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:layout_centerInParent="true"
  android:gravity="center">

  <ImageView android:id="@+id/myImageView" 
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:src="@drawable/icon"/>
  </LinearLayout>  

</RelativeLayout>

现在您可以在任何地方使用这个 main.xmlAcitivty这将打开一个带有ImageView。 谢谢....