Question

 public class AndroidCamera extends Activity implements  SurfaceHolder.Callback{

Camera camera;
SurfaceView surfaceView;
SurfaceHolder surfaceHolder;
boolean previewing = false;;
PictureCallback rawCallback;
ShutterCallback shutterCallback;
PictureCallback jpegCallback;
private Bitmap bitmap;
TextView colorRGB;
Config config;
String callname;

String callnameRimage;


EditText txtData, PatientInfo,PatientAge;


ImageView imageView = null;
ImageView imageView2 = null;



@Override
protected void onCreate(Bundle savedInstanceState) 
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);


   Button buttonStartCameraPreview = (Button)findViewById(R.id.startcamerapreview);
   Button buttonStopCameraPreview = (Button)findViewById(R.id.stopcamerapreview);
   Button buttonCapturePreview = (Button) findViewById(R.id.capturepreview);
  Button testButton = (Button) findViewById(R.id.testButton); 



getWindow().setFormat(PixelFormat.UNKNOWN);
surfaceView = (SurfaceView)findViewById(R.id.surfaceview);
surfaceHolder = surfaceView.getHolder();
surfaceHolder.addCallback(this);





rawCallback = new PictureCallback() 
{
    public void onPictureTaken(byte[] data, Camera camera)
    {
        Log.d("Log", "onPictureTaken - raw");
    }
};

shutterCallback = new ShutterCallback()
{
    public void onShutter() {
        Log.i("Log", "onShutter'd");
    }
};

jpegCallback = new PictureCallback()
{
    public void onPictureTaken(byte[] data, Camera camera) 
     {

        Intent imageIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
        File imagesFolder = new File(Environment.getExternalStorageDirectory(), "Image");
        imagesFolder.mkdirs(); 
        Date d = new Date();
        CharSequence s  = DateFormat.format("MM-dd-yy hh-mm-ss", d.getTime());
        name = s.toString() + ".jpg";

        File output = new File(imagesFolder, name);
        callname = "/sdcard/Asw/Raw Image/" + name;

        Uri uriSavedImage = Uri.fromFile(output);
        imageIntent.putExtra(MediaStore.EXTRA_OUTPUT, uriSavedImage);

        OutputStream imageFileOS;

        try {

            imageFileOS = getContentResolver().openOutputStream(uriSavedImage);
            imageFileOS.write(data);
            imageFileOS.flush();
            imageFileOS.close();

            } 
        catch (FileNotFoundException e) 
            {
            e.printStackTrace();
            } 
        catch (IOException e)
        {
            e.printStackTrace();

        } 
        finally
        {}
        Log.d("Log", "onPictureTaken - jpeg");




buttonStartCameraPreview.setOnClickListener(new Button.OnClickListener()
{

    @TargetApi(Build.VERSION_CODES.GINGERBREAD)
    @Override
    public void onClick(View v) 
    {
        if(!previewing)
        {
            camera = Camera.open(0);
            if (camera != null)
            {

                try {

                    camera.setPreviewDisplay(surfaceHolder);
                    camera.startPreview();
                    previewing = true;

                    } 
                catch (IOException e) 
                    {

                    e.printStackTrace();
                    }
            }else txtData.setText("null");
        }
    }});



buttonCapturePreview.setOnClickListener(new OnClickListener()
  {

    @Override
    public void onClick(View v) 
    {

        captureImage();
    }


});


buttonStopCameraPreview.setOnClickListener(new Button.OnClickListener(){

    @Override
    public void onClick(View v) 
    {

        if(camera != null && previewing)
        {
            camera.stopPreview();
            camera.release();
            camera = null;

            previewing = false;
        }
    }});
 }

private void captureImage() 
   {
     camera.takePicture(shutterCallback, rawCallback, jpegCallback);
  }

  private void displayimages()
  {

setContentView(R.layout.display);
callnameRimage = "/sdcard/Asw/Raw Image/" + name;
Bitmap bitmap1 = BitmapFactory.decodeFile(callnameRimage);

imageView2=(ImageView)findViewById(R.id.imageView2);
    imageView2.setImageBitmap(bitmap1);



   Button backButton = (Button) findViewById(R.id.back);

backButton.setOnClickListener(new OnClickListener()
{

    @Override
    public void onClick(View v)
    {
     finish();  
     Intent intent = new Intent(AndroidCamera.this, AndroidCamera.class);
     startActivity(intent);

    }
    });

   }

  }

我想查看上一张图片，然后点按一下按钮。图像存储在文件夹中。该文件夹将包含许多图像，这些图像以日期和时间作为图像名称存储。我希望通过比较其日期和时间来获取上一张图片。任何人都可以建议我更轻松地做到这一点

Answer 1

获取文件名，格式化它们然后您可以将日期与以下内容进行比较：

date1.compareTo(date2);

相等时返回0.

当date1更早时返回低于0的值。

当date2更早时返回高于0的值。

通过比较日期和时间查看以前的图像：Android

1 个答案: