在我的应用程序中，我可以选择拍照，该照片将保存在文件夹中：
Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES) + "/my-images";
图像保存得很好，我也可以选择使用此代码的图像：
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, "Select Picture"), SELECT_PICTURE);
这里最初用来显示2个画廊
1。摄像机
2。我的图像
选择他们中的任何一个......，一切正常。
但我无缘无故地删除了my-images文件夹并再次运行了该应用程序。将再次创建相同的文件夹，并按预期保存图像。
问题是：
当我点击选择图片按钮时，我的图片库现在没有显示。
除了删除my-images文件夹并重新启动应用程序外，我还没有更改任何代码，因为它曾经运作良好。
为什么会这样？
谢谢
修改
我的活动代码，允许用户拍照并存储在SD卡上，并浏览图片库：
public class PictureFromAppActivity extends SherlockActivity {
private File dir;
private Bitmap photo;
private String encodedString;
private InputStream is;
private ImageView imagePreview;
private String selectedImagePath;
private static final int CAMERA_REQUEST = 1888;
private static final int SELECT_PICTURE = 1;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
imagePreview = (ImageView) findViewById(R.id.image_preview);
Button takePicture = (Button) findViewById(R.id.take_a_picture);
Button selectImage = (Button) findViewById(R.id.select_picture);
takePicture.setOnClickListener(new View.OnClickListener() {
public void onClick(View arg0) {
if (android.os.Environment.getExternalStorageState().equals(
android.os.Environment.MEDIA_MOUNTED)) {
Intent cameraIntent = new Intent(
android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(cameraIntent, CAMERA_REQUEST);
}
}
});
selectImage.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View arg0) {
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(
Intent.createChooser(intent, "Select Picture"),
SELECT_PICTURE);
}
});
}
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK) {
if (requestCode == CAMERA_REQUEST) {
if (data != null) {
photo = (Bitmap) data.getExtras().get("data");
Bitmap bitmapOrg = photo;
ByteArrayOutputStream bao = new ByteArrayOutputStream();
bitmapOrg.compress(Bitmap.CompressFormat.PNG, 100, bao);
byte[] ba = bao.toByteArray();
try {
encodedString = Base64.encodeBytes(ba, 0);
} catch (IOException e1) {
}
if (android.os.Environment.getExternalStorageState()
.equals(android.os.Environment.MEDIA_MOUNTED)) {
File imagesFolder = new File(
Environment
.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES),
"/my-images");
if (!imagesFolder.exists()) {
imagesFolder.mkdirs();
} else {
}
String fileName = "image_" + count + ".jpg";
f = new File(imagesFolder, fileName);
while (f.exists()) {
count++;
fileName = "image_" + String.valueOf(count)
+ ".jpg";
f = new File(
Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES)
+ "/my-images", fileName);
}
} else {
}
f.createNewFile();
FileOutputStream fo = new FileOutputStream(f);
fo.write(ba);
o.flush();
fo.close();
try {
File imageFile = new File(
Environment
.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES)
+ "/my-images" + "/image_" + count + ".jpg");
Bitmap bitmap = BitmapFactory.decodeFile(imageFile
.getAbsolutePath());
imagePreview.setImageBitmap(bitmap);
Log.d("Image Width", "+" + imagePreview.getWidth());
Log.d("Image Height", "+" + imagePreview.getHeight());
} catch (Exception e) {
}
} else {
Intent intent = new Intent(PictureFromAppActivity.this,
PictureFromAppActivity.class);
startActivity(intent);
}
} else if (requestCode == SELECT_PICTURE) {
if (data != null) {
Uri selectedImageUri = data.getData();
selectedImagePath = getPath(selectedImageUri);
try {
File imageFile = new File(selectedImagePath);
Bitmap bitmap = BitmapFactory.decodeFile(imageFile
.getAbsolutePath());
imagePreview.setImageBitmap(bitmap);
} catch (Exception e) {
}
} else {
}
}
}
}
private String getPath(Uri selectedImageUri) {
String[] projection = { MediaStore.Images.Media.DATA };
Cursor cursor = managedQuery(selectedImageUri, projection, null, null, null);
int column_index = cursor
.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
}
}
答案 0 :(得分：4)
可能是因为图库与您的应用程序相关联并且使用它来保持视图。 因此，当您删除从系统中删除的图像/文件夹时会发生什么，但未更新与您的应用程序关联的媒体库。 请使用以下代码，如果这可以解决您的问题，请告诉我
sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED,
Uri.parse("file://"
+ Environment.getExternalStorageDirectory())));
请使用此代码打开图库
中的图片intent = new Intent(
Intent.ACTION_PICK,
android.provider.MediaStore.Images.Media.INTERNAL_CONTENT_URI);
startActivityForResult(intent, PICK_PHOTO);
在您的活动结果中
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
String path = "";
switch (requestCode) {
case PICK_PHOTO:
if (resultCode == RESULT_OK) {
Uri uri = data.getData();
path = pathFromUri(uri); // Now you can get the path of your selected image from here
}
break;
}
}
从URI代码获取路径
/**
* Method to get path from uri
*
* @param Uri
* uri
* @return String path
* */
private String pathFromUri(Uri uri) {
String[] filePathColumn = { MediaStore.Images.Media.DATA };
Cursor cursor = getContentResolver().query(uri, filePathColumn, null,
null, null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
String filePath = cursor.getString(columnIndex);
cursor.close();
return filePath;
}