所以我想从覆盖onActivityResult的图库中加载图像。将意图数据发送到另一个活动的有效方法是什么？
目前使用此代码在将图像路径发送到其他活动之前获取图像路径：
protected void onActivityResult(final int requestCode, final int resultCode, final Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == PICK_IMAGE && resultCode == RESULT_OK && null != data) {
Uri selected_image = data.getData();
if (selected_image.toString().substring(0, 21).equals("content://com.android")) {
String[] photo_split = selected_image.toString().split("%3A");
String imageUriBasePath = "content://media/external/images/media/" + photo_split[1];
selected_image = Uri.parse(imageUriBasePath);
}
String[] file_path_column = {MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query(selected_image, file_path_column, null, null, null);
cursor.moveToFirst();
int column_index = cursor.getColumnIndex(file_path_column[0]);
image_path = cursor.getString(column_index);
cursor.close();
Intent intent = new Intent(MainActivity.this, ImageActivity.class);
intent.putExtra("imagePath", image_path);
startActivity(intent);
}
}
问题是这段代码看起来效果不好，因为从图库应用程序中选择图像后，图库会在将图像加载到其他活动之前滞后几秒钟。
答案 0 :(得分：0)
试试这个，以下是从相机和图库中获取图像：
ImageView photo;
Bitmap bmp;
static int GET_PICTURE = 1, CAMERA_PIC_REQUEST = 2;
static String selectedImagePath = "";
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK) {
if (requestCode == CAMERA_PIC_REQUEST) {
// deleteDialog.dismiss();
bmp = (Bitmap) data.getExtras().get("data");
} else if (requestCode == GET_PICTURE) {
if (bmp != null) {
bmp.recycle();
}
// deleteDialog.dismiss();
Uri selectedImageUri = data.getData();
selectedImagePath = getRealPathFromURI(selectedImageUri);
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(selectedImagePath, options);
options.inSampleSize = calculateInSampleSize(options, 200,
200);
options.inJustDecodeBounds = false;
bmp = BitmapFactory.decodeFile(selectedImagePath, options);
}
if (bmp != null) {
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bmp.compress(Bitmap.CompressFormat.PNG, 100, stream);
Bitmap outputs = getRoundedBitmap(bmp,10);
last = Bitmap.createScaledBitmap(outputs, 200, 200, false);
if (last != null) {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
last.compress(Bitmap.CompressFormat.PNG, 100, baos);
byte[] b = baos.toByteArray();
String temp = Base64.encodeToString(b, Base64.DEFAULT);
photo.setImageBitmap(last);
// userimage.setBackgroundResource(android.R.color.transparent);
}
} else {
Toast.makeText(getBaseContext(), "Invalid image",
Toast.LENGTH_SHORT).show();
}
}
}
public static Bitmap getRoundedBitmap(Bitmap bitmap,int pixels) {
final Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),
bitmap.getHeight(), Bitmap.Config.ARGB_8888);
final Canvas canvas = new Canvas(output);
final int color = Color.RED;
final Paint paint = new Paint();
final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
final RectF rectF = new RectF(rect);
final float roundPx = pixels;
paint.setAntiAlias(true);
canvas.drawARGB(0, 0, 0, 0);
paint.setColor(color);
canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
//canvas.drawOval(rectF, paint);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(bitmap, rect, rect, paint);
bitmap.recycle();
return output;
}
private String getRealPathFromURI(Uri contentURI) {
String result;
Cursor cursor = getContentResolver().query(contentURI, null, null,
null, null);
if (cursor == null) {
result = contentURI.getPath();
} else {
cursor.moveToFirst();
int idx = cursor
.getColumnIndex(MediaStore.Images.ImageColumns.DATA);
result = cursor.getString(idx);
}
cursor.close();
return result;
}
public static int calculateInSampleSize(BitmapFactory.Options options,
int reqWidth, int reqHeight) {
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
final int halfHeight = height / 2;
final int halfWidth = width / 2;
// Calculate the largest inSampleSize value that is a power of 2 and
// keeps both
// height and width larger than the requested height and width.
while ((halfHeight / inSampleSize) > reqHeight
&& (halfWidth / inSampleSize) > reqWidth) {
inSampleSize *= 2;
}
}
return inSampleSize;
}
答案 1 :(得分：0)
// Opening gallery
Intent intent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(Intent.createChooser(intent, "Select Picture"), Keys.PICTURE_REQ_CODE);
// Opening gallery
Intent intent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(Intent.createChooser(intent, "Select Picture"), Keys.PICTURE_REQ_CODE);