Android 如何在拍摄图像时显示当前日期和时间，并将其与日期和时间一起保存在我的SD卡中

我正在从事Android应用程序开发。我的目的是使用设备摄像头拍摄图像，并希望在拍摄的图像上显示当前日期和时间，并将整个图像作为单个图像保存在SD卡上。有谁能和我分享你的想法，帮我解决问题吗

提前谢谢

public class MainActivity extends Activity {

// Activity request codes
private static final int CAMERA_CAPTURE_IMAGE_REQUEST_CODE = 100;
private static final int CAMERA_CAPTURE_VIDEO_REQUEST_CODE = 200;
public static final int MEDIA_TYPE_IMAGE = 1;
public static final int MEDIA_TYPE_VIDEO = 2;

// directory name to store captured images and videos
private static final String IMAGE_DIRECTORY_NAME = "Hello Camera";

private Uri fileUri; // file url to store image/video

private ImageView imgPreview;
private VideoView videoPreview;
private Button btnCapturePicture, btnRecordVideo;

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

    imgPreview = (ImageView) findViewById(R.id.imgPreview);
    videoPreview = (VideoView) findViewById(R.id.videoPreview);
    btnCapturePicture = (Button) findViewById(R.id.btnCapturePicture);
    btnRecordVideo = (Button) findViewById(R.id.btnRecordVideo);

    /*
     * Capture image button click event
     */
    btnCapturePicture.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // capture picture
            captureImage();
        }
    });

    /*
     * Record video button click event
     */
    btnRecordVideo.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // record video
            recordVideo();
        }
    });

    // Checking camera availability
    if (!isDeviceSupportCamera()) {
        Toast.makeText(getApplicationContext(),
                "Sorry! Your device doesn't support camera",
                Toast.LENGTH_LONG).show();
        // will close the app if the device does't have camera
        finish();
    }
}

/**
 * Checking device has camera hardware or not
 * */
private boolean isDeviceSupportCamera() {
    if (getApplicationContext().getPackageManager().hasSystemFeature(
            PackageManager.FEATURE_CAMERA)) {
        // this device has a camera
        return true;
    } else {
        // no camera on this device
        return false;
    }
}

/*
 * Capturing Camera Image will lauch camera app requrest image capture
 */
private void captureImage() {
    Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

    fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE);

    intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);

    // start the image capture Intent
    startActivityForResult(intent, CAMERA_CAPTURE_IMAGE_REQUEST_CODE);
}

/*
 * Here we store the file url as it will be null after returning from camera
 * app
 */
@Override
protected void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);

    // save file url in bundle as it will be null on scren orientation
    // changes
    outState.putParcelable("file_uri", fileUri);
}

@Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
    super.onRestoreInstanceState(savedInstanceState);

    // get the file url
    fileUri = savedInstanceState.getParcelable("file_uri");
}

/*
 * Recording video
 */
private void recordVideo() {
    Intent intent = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);

    fileUri = getOutputMediaFileUri(MEDIA_TYPE_VIDEO);

    // set video quality
    intent.putExtra(MediaStore.EXTRA_VIDEO_QUALITY, 1);

    intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri); // set the image file
                                                        // name

    // start the video capture Intent
    startActivityForResult(intent, CAMERA_CAPTURE_VIDEO_REQUEST_CODE);
}

/**
 * Receiving activity result method will be called after closing the camera
 * */
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    // if the result is capturing Image
    if (requestCode == CAMERA_CAPTURE_IMAGE_REQUEST_CODE) {
        if (resultCode == RESULT_OK) {
            // successfully captured the image
            // display it in image view
            previewCapturedImage();
        } else if (resultCode == RESULT_CANCELED) {
            // user cancelled Image capture
            Toast.makeText(getApplicationContext(),
                    "User cancelled image capture", Toast.LENGTH_SHORT)
                    .show();
        } else {
            // failed to capture image
            Toast.makeText(getApplicationContext(),
                    "Sorry! Failed to capture image", Toast.LENGTH_SHORT)
                    .show();
        }
    } else if (requestCode == CAMERA_CAPTURE_VIDEO_REQUEST_CODE) {
        if (resultCode == RESULT_OK) {
            // video successfully recorded
            // preview the recorded video
            previewVideo();
        } else if (resultCode == RESULT_CANCELED) {
            // user cancelled recording
            Toast.makeText(getApplicationContext(),
                    "User cancelled video recording", Toast.LENGTH_SHORT)
                    .show();
        } else {
            // failed to record video
            Toast.makeText(getApplicationContext(),
                    "Sorry! Failed to record video", Toast.LENGTH_SHORT)
                    .show();
        }
    }
}

/*
 * Display image from a path to ImageView
 */
private void previewCapturedImage() {
    try {
        // hide video preview
        videoPreview.setVisibility(View.GONE);

        imgPreview.setVisibility(View.VISIBLE);

        // bimatp factory
        BitmapFactory.Options options = new BitmapFactory.Options();

        // downsizing image as it throws OutOfMemory Exception for larger
        // images
        options.inSampleSize = 8;

        final Bitmap bitmap = BitmapFactory.decodeFile(fileUri.getPath(),
                options);

        imgPreview.setImageBitmap(bitmap);
    } catch (NullPointerException e) {
        e.printStackTrace();
    }
}

/*
 * Previewing recorded video
 */
private void previewVideo() {
    try {
        // hide image preview
        imgPreview.setVisibility(View.GONE);

        videoPreview.setVisibility(View.VISIBLE);
        videoPreview.setVideoPath(fileUri.getPath());
        // start playing
        videoPreview.start();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

/**
 * ------------ Helper Methods ---------------------- 
 * */

/*
 * Creating file uri to store image/video
 */
public Uri getOutputMediaFileUri(int type) {
    return Uri.fromFile(getOutputMediaFile(type));
}

/*
 * returning image / video
 */
private static File getOutputMediaFile(int type) {

    // External sdcard location
    File mediaStorageDir = new File(
            Environment
                    .getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES),
            IMAGE_DIRECTORY_NAME);

    // Create the storage directory if it does not exist
    if (!mediaStorageDir.exists()) {
        if (!mediaStorageDir.mkdirs()) {
            Log.d(IMAGE_DIRECTORY_NAME, "Oops! Failed create "
                    + IMAGE_DIRECTORY_NAME + " directory");
            return null;
        }
    }

    // Create a media file name
    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss",
            Locale.getDefault()).format(new Date());
    File mediaFile;
    if (type == MEDIA_TYPE_IMAGE) {
        mediaFile = new File(mediaStorageDir.getPath() + File.separator
                + "IMG_" + timeStamp + ".jpg");
    } else if (type == MEDIA_TYPE_VIDEO) {
        mediaFile = new File(mediaStorageDir.getPath() + File.separator
                + "VID_" + timeStamp + ".mp4");
    } else {
        return null;
    }

    return mediaFile;
}
}

---

给你这个

    private void save_Image_to_sdcard() {
    // TODO Auto-generated method stub
    OutputStream file_outputstream = null;
    InputStream in = null;
    try {
        URL path = new URL(url);
        in = path.openStream();



        String path1 =    
Environment.getExternalStorageDirectory().toString();
        System.out.println(path1+ "    " +user_file_name);
        // /mnt/sdcard
        File f = new File(path1 + "/"+System.currentTimeMillis()+".png");
        f.createNewFile();
        System.out.println("file created " + f.toString());

        file_outputstream = new FileOutputStream(f);
        byte[] buffer = new byte[1024];
        int bytesRead = 0;
        while ((bytesRead = in.read(buffer, 0, buffer.length)) >= 0) {

            file_outputstream.write(buffer, 0, bytesRead);

        }

        file_outputstream.close();
        in.close();

    } catch (MalformedURLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        Log.v("ok", "error");
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        Log.v("ok", " ioexception");
    }

}

---

试试这种方法，希望这能帮助你解决问题。

private static File getOutputMediaFile(int type) {
   File mediaFile=null;
   if (type == MEDIA_TYPE_IMAGE) {
       mediaFile = new File(Environment.getExternalStorageDirectory() + "/DCIM/", "IMG_" + new Date().getTime() + ".jpg");
   } else if (type == MEDIA_TYPE_VIDEO) {
       mediaFile = new File(Environment.getExternalStorageDirectory() + "/DCIM/", "VID_" + new Date().getTime() + ".mp4");
   } 
 return mediaFile;
}

---

你做过任何事情吗？我们不是在这里做你的家庭作业吗？是的，我在这里附上我的代码。谢谢你的回复！但我想在图像上显示当前日期和时间，然后从图像名称中提取日期和时间字符串。