使用 . 打开相机时MediaStore.ACTION_IMAGE_CAPTURE intent，尽管没有保存图像，但它会在 sd 卡中保存一个 0kb 或空白文件，即使我不保存图像或丢弃图像或只是返回。编辑:: 但是如果我保存图像，它会保存正确的图像。下面是我正在处理的代码：
import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.PointF;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.util.FloatMath;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.VideoView;
public class DocsAdd extends Activity
{
private static final int ACTION_TAKE_PHOTO_B = 1;
private static final String BITMAP_STORAGE_KEY = "viewbitmap";
private static final String IMAGEVIEW_VISIBILITY_STORAGE_KEY = "imageviewvisibility";
private ImageView mImageView;
private Bitmap mImageBitmap;
private String mCurrentPhotoPath;
private static final String JPEG_FILE_PREFIX = "IMG_";
private static final String JPEG_FILE_SUFFIX = ".jpg";
private File getAlbumDir()
{
Log.i("inside ", "docs add");
String path = Environment.getExternalStorageDirectory().toString();
File filenamedemo = new File(path + "/AutoistDiary/ImageFolder/");
String name=String.valueOf(filenamedemo);
if (Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState()))
{
if (name != null)
{
if (! filenamedemo.mkdirs())
{
if (! filenamedemo.exists())
{
Log.d("CameraSample", "failed to create directory");
return null;
}
}
}
} else {
}
return filenamedemo;
}
private File createImageFile() throws IOException {
// Create an image file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
String imageFileName = JPEG_FILE_PREFIX + timeStamp + "_";
File albumF = getAlbumDir();
File imageF = File.createTempFile(imageFileName, JPEG_FILE_SUFFIX, albumF);
return imageF;
}
private File setUpPhotoFile() throws IOException {
File f = createImageFile();
mCurrentPhotoPath = f.getAbsolutePath();
return f;
}
private void galleryAddPic() {
Intent mediaScanIntent = new Intent("android.intent.action.MEDIA_SCANNER_SCAN_FILE");
File f = new File(mCurrentPhotoPath);
Uri contentUri = Uri.fromFile(f);
mediaScanIntent.setData(contentUri);
this.sendBroadcast(mediaScanIntent);
}
private void dispatchTakePictureIntent() {
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
File f = null;
try {
f = setUpPhotoFile();
mCurrentPhotoPath = f.getAbsolutePath();
takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(f));
} catch (IOException e) {
e.printStackTrace();
f = null;
mCurrentPhotoPath = null;
}
startActivityForResult(takePictureIntent,0);
}
private void handleBigCameraPhoto()
{
if (mCurrentPhotoPath != null)
{
//setPic();
galleryAddPic();
mCurrentPhotoPath = null;
Intent viewint=new Intent(DocsAdd.this, DocsShow.class);
Log.i("calling ", "view activity");
startActivity(viewint);
finish();
}
}
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
dispatchTakePictureIntent();
/*if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.FROYO) {
mAlbumStorageDirFactory = new FroyoAlbumDirFactory();
} else {
mAlbumStorageDirFactory = new BaseAlbumDirFactory();
}*/
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data)
{
handleBigCameraPhoto();
}
// Some lifecycle callbacks so that the image can survive orientation change
@Override
protected void onSaveInstanceState(Bundle outState) {
outState.putParcelable(BITMAP_STORAGE_KEY, mImageBitmap);
outState.putBoolean(IMAGEVIEW_VISIBILITY_STORAGE_KEY, (mImageBitmap != null) );
super.onSaveInstanceState(outState);
}
@Override
protected void onRestoreInstanceState(Bundle savedInstanceState)
{
super.onRestoreInstanceState(savedInstanceState);
mImageBitmap = savedInstanceState.getParcelable(BITMAP_STORAGE_KEY);
mImageView.setImageBitmap(mImageBitmap);
mImageView.setVisibility(
savedInstanceState.getBoolean(IMAGEVIEW_VISIBILITY_STORAGE_KEY) ?
ImageView.VISIBLE : ImageView.INVISIBLE
);
}
/**
* Indicates whether the specified action can be used as an intent. This
* method queries the package manager for installed packages that can
* respond to an intent with the specified action. If no suitable package is
* found, this method returns false.
* http://android-developers.blogspot.com/2009/01/can-i-use-this-intent.html
*
* @param context The application's environment.
* @param action The Intent action to check for availability.
*
* @return True if an Intent with the specified action can be sent and
* responded to, false otherwise.
*/
public static boolean isIntentAvailable(Context context, String action)
{
final PackageManager packageManager = context.getPackageManager();
final Intent intent = new Intent(action);
List<ResolveInfo> list =packageManager.queryIntentActivities(intent,PackageManager.MATCH_DEFAULT_ONLY);
return list.size() > 0;
}
/** Show an event in the LogCat view, for debugging */
private void dumpEvent(MotionEvent event) {
String names[] = { "DOWN", "UP", "MOVE", "CANCEL", "OUTSIDE",
"POINTER_DOWN", "POINTER_UP", "7?", "8?", "9?" };
StringBuilder sb = new StringBuilder();
int action = event.getAction();
int actionCode = action & MotionEvent.ACTION_MASK;
sb.append("event ACTION_").append(names[actionCode]);
if (actionCode == MotionEvent.ACTION_POINTER_DOWN
|| actionCode == MotionEvent.ACTION_POINTER_UP) {
sb.append("(pid ").append(
action >> MotionEvent.ACTION_POINTER_ID_SHIFT);
sb.append(")");
}
sb.append("[");
for (int i = 0; i < event.getPointerCount(); i++) {
sb.append("#").append(i);
sb.append("(pid ").append(event.getPointerId(i));
sb.append(")=").append((int) event.getX(i));
sb.append(",").append((int) event.getY(i));
if (i + 1 < event.getPointerCount())
sb.append(";");
}
sb.append("]");
}
/** Determine the space between the first two fingers */
private float spacing(MotionEvent event) {
float x = event.getX(0) - event.getX(1);
float y = event.getY(0) - event.getY(1);
return FloatMath.sqrt(x * x + y * y);
}
/** Calculate the mid point of the first two fingers */
private void midPoint(PointF point, MotionEvent event) {
float x = event.getX(0) + event.getX(1);
float y = event.getY(0) + event.getY(1);
point.set(x / 2, y / 2);
}
public void onCancel()
{
// TODO Auto-generated method stub
Log.i("on click", "discard image");
Log.d("on click", "discard image hahahahahaaaaaa");
}
}
任何人都可以指出为什么保存空白文件或可以针对此问题做些什么。