我正在处理应用程序，我希望用户可以从库中选择图像，以便他可以在其上应用框架。我成功访问了移动图库，现在我想知道如何保存所选图像以便进一步处理。所选图像将用于在其上应用帧。
答案 0 :(得分：1)
你走了。
protected void onActivityResult(int requestCode, int resultCode, Intent imageReturnedIntent) {
super.onActivityResult(requestCode, resultCode, imageReturnedIntent);
switch(requestCode) {
case REQ_CODE_PICK_IMAGE:
if(resultCode == RESULT_OK){
Uri selectedImage = imageReturnedIntent.getData();
String[] filePathColumn = {MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query(selectedImage, filePathColumn, null, null, null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
String filePath = cursor.getString(columnIndex);
cursor.close();
Bitmap yourSelectedImage = BitmapFactory.decodeFile(filePath);
//Now do whatever processing you want to do on it.
}
}
}
答案 1 :(得分：0)
使用以下代码从图库中选择图片：
Intent intent=new Intent();
intent.setType=("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent,"Select Picture"), PICK_IMAGE);
/*Declare PICK_IMAGE globally : private static final int PICK_IMAGE = 1; */
实际代码从这里开始
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case PICK_IMAGE:
if (resultCode == Activity.RESULT_OK) {
Uri selectedImageUri = data.getData();
try {
// OI FILE Manager
String filemanagerstring = selectedImageUri.getPath();
// MEDIA GALLERY
String selectedImagePath = getPath(selectedImageUri);
if (selectedImagePath != null) {
filePath = selectedImagePath;
} else if (filemanagerstring != null) {
filePath = filemanagerstring;
} else {
Toast.makeText(getApplicationContext(), "Unknown path",
Toast.LENGTH_LONG).show();
Log.e("Bitmap", "Unknown path");
}
if (filePath != null) {
Log.e("file path ","file path "+filePath);
GlobalValues.camefromtw="true";
decodeFile(filePath);
} else {
bitmap = null;
}
} catch (Exception e) {
Toast.makeText(getApplicationContext(), "Internal error",
Toast.LENGTH_LONG).show();
Log.e(e.getClass().getName(), e.getMessage(), e);
}
}
break;protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case PICK_IMAGE:
Log.e("result code","result code"+resultCode+" result "+Activity.RESULT_OK);
if (resultCode == Activity.RESULT_OK) {
Uri selectedImageUri = data.getData();
try {
// OI FILE Manager
String filemanagerstring = selectedImageUri.getPath();
// MEDIA GALLERY
String selectedImagePath = getPath(selectedImageUri);
if (selectedImagePath != null) {
filePath = selectedImagePath;
} else if (filemanagerstring != null) {
filePath = filemanagerstring;
} else {
Toast.makeText(getApplicationContext(), "Unknown path",
Toast.LENGTH_LONG).show();
Log.e("Bitmap", "Unknown path");
}
if (filePath != null) {
decodeFile(filePath);
} else {
bitmap = null;
}
} catch (Exception e) {
Toast.makeText(getApplicationContext(), "Internal error",
Toast.LENGTH_LONG).show();
Log.e(e.getClass().getName(), e.getMessage(), e);
}
}
break;
default:
}
图片收到文件路径现在你可以使用它，在这个代码我在这里使用thi sto set ImageView
public void decodeFile(String filePath) {
// Decode image size
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
BitmapFactory.decodeFile(filePath, o);
// The new size we want to scale to
final int REQUIRED_SIZE = 1024;
// Find the correct scale value. It should be the power of 2.
int width_tmp = o.outWidth, height_tmp = o.outHeight;
int scale = 1;
while (true) {
if (width_tmp < REQUIRED_SIZE && height_tmp < REQUIRED_SIZE)
break;
width_tmp /= 2;
height_tmp /= 2;
scale *= 2;
}
// Decode with inSampleSize
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize = scale;
bitmap = BitmapFactory.decodeFile(filePath, o2);
image.setImageBitmap(bitmap);
}
答案 2 :(得分：0)
首先添加：
ImageView profile;
Bitmap bmp;
SharedPreferences sp;
public static final int PERMISSION_REQUEST_CAMERA = 1;
private static final int PICK_FROM_GALLERY = 1;
然后在onCreate方法中添加以下代码行：
sp=getSharedPreferences("profilePicture",MODE_PRIVATE);
profile=(ImageView)findViewById(R.id.profile);
if(!sp.getString("dp","").equals("")){
byte[] decodedString = Base64.decode(sp.getString("dp", ""), Base64.DEFAULT);
Bitmap decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length);
profile.setImageBitmap(decodedByte);
}
profile.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
openGallery();
}
});
然后添加这些函数openGallery（）：
private void openGallery() {
if (ActivityCompat.checkSelfPermission(ProfileActivity.this, Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(ProfileActivity.this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE, Manifest.permission.WRITE_EXTERNAL_STORAGE}, PICK_FROM_GALLERY);
}else {
Intent photoPickerIntent = new Intent(Intent.ACTION_PICK);
photoPickerIntent.setType("image/*");
startActivityForResult(photoPickerIntent, 1);
}
}
然后添加this，onRequestPermissionsResult（）：
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String permissions[], @NonNull int[] grantResults)
{
switch (requestCode) {
case PICK_FROM_GALLERY:
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
Intent galleryIntent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(galleryIntent, PICK_FROM_GALLERY);
} else {
Toast.makeText(ProfileActivity.this,"Not working",Toast.LENGTH_LONG).show();
//do something like displaying a message that he didn`t allow the app to access gallery and you wont be able to let him select from gallery
}
break;
}
}
onActivityResult（）：
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data)
{
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK) {
try { // When an Image is picked
if (requestCode == PICK_FROM_GALLERY && resultCode == RESULT_OK
&& null != data) {
// Get the Image from data
Uri selectedImage = data.getData();
String[] filePathColumn = { MediaStore.Images.Media.DATA };
// Get the cursor
Cursor cursor = getContentResolver().query(selectedImage,
filePathColumn, null, null, null);
// Move to first row
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
String imgDecodableString = cursor.getString(columnIndex);
cursor.close();
// Set the Image in ImageView after decoding the String
bmp = BitmapFactory
.decodeFile(imgDecodableString);
profile.setImageBitmap(bmp);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bmp.compress(Bitmap.CompressFormat.PNG, 100, stream);
byte[] byteArray = stream.toByteArray();
String encodedImage = Base64.encodeToString(byteArray, Base64.DEFAULT);
sp.edit().putString("dp", encodedImage).commit();
} else {
Toast.makeText(this, "You haven't picked Image",
Toast.LENGTH_LONG).show();
}
} catch (Exception e) {
e.printStackTrace();
Toast.makeText(ProfileActivity.this, "Something went wrong", Toast.LENGTH_LONG).show();
}
}else {
Toast.makeText(ProfileActivity.this, "You haven't picked Image",Toast.LENGTH_LONG).show();
}
}
不要忘记在Manifest文件中授予权限。