如何在android中select和裁剪图像？

嘿，我目前正在做一个dynamic的壁纸，我允许用户select一个图像，这将是我的影响。

目前我有：

Intent i = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI); i.putExtra("crop", "true"); startActivityForResult(i, 1); 

还有一点：

 @Override public void onActivityResult(int requestCode, int resultCode, Intent data) { super.onActivityResult(requestCode, resultCode, data); if (requestCode == 1) if (resultCode == Activity.RESULT_OK) { Uri selectedImage = data.getData(); Log.d("IMAGE SEL", "" + selectedImage); // TODO Do something with the select image URI SharedPreferences customSharedPreference = getSharedPreferences("imagePref", Activity.MODE_PRIVATE); SharedPreferences.Editor editor = customSharedPreference.edit(); Log.d("HO", "" + selectedImage); editor.putString("imagePref", getRealPathFromURI(selectedImage)); Log.d("IMAGE SEL", getRealPathFromURI(selectedImage)); editor.commit(); } } 

当我的代码运行时，Logcat告诉我selectedImage是null。 如果我注释掉了

 i.putExtra("crop", "true"): 

Logcat不给我的空指针exception，我能做我想要的图像。 那么，这里有什么问题？ 有没有人知道如何解决这个问题？ 谢谢你的时间。

Answer 1

我也遇到了这个问题。你可以试试这个代码。 它为我工作很好

 private static final String TEMP_PHOTO_FILE = "temporary_holder.jpg"; Intent photoPickerIntent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI); photoPickerIntent.setType("image/*"); photoPickerIntent.putExtra("crop", "true"); photoPickerIntent.putExtra(MediaStore.EXTRA_OUTPUT, getTempUri()); photoPickerIntent.putExtra("outputFormat", Bitmap.CompressFormat.JPEG.toString()); startActivityForResult(photoPickerIntent, REQ_CODE_PICK_IMAGE); private Uri getTempUri() { return Uri.fromFile(getTempFile()); } private File getTempFile() { if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) { File file = new File(Environment.getExternalStorageDirectory(),TEMP_PHOTO_FILE); try { file.createNewFile(); } catch (IOException e) {} return file; } else { return null; } } 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) { if (imageReturnedIntent!=null) { File tempFile = getTempFile(); String filePath= Environment.getExternalStorageDirectory() +"/"+TEMP_PHOTO_FILE; System.out.println("path "+filePath); Bitmap selectedImage = BitmapFactory.decodeFile(filePath); _image = (ImageView) findViewById(R.id.image); _image.setImageBitmap(selectedImage ); if (tempFile.exists()) tempFile.delete(); } } } } 

Answer 2

你不需要一个Temp文件：

 protected static final int REQ_CODE_PICK_IMAGE = 1; Intent photoPickerIntent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI); photoPickerIntent.setType("image/*"); photoPickerIntent.putExtra("crop", "true"); photoPickerIntent.putExtra("return-data", true); photoPickerIntent.putExtra("outputFormat", Bitmap.CompressFormat.JPEG.toString()); startActivityForResult(photoPickerIntent, REQ_CODE_PICK_IMAGE); 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) { if (imageReturnedIntent!=null) { Bundle extras = imageReturnedIntent.getExtras(); Bitmap selectedBitmap = extras.getParcelable("data"); imageR = (ImageView) findViewById(R.id.image); imageR.setImageBitmap(selectedBitmap); } } } } 

Answer 3

这个代码适合“初学者”^^

 private Bitmap FixBitmap; Bitmap thePicBitmap; String ImagePath = "image_path"; String ImagePath_1; private static final String TEMP_PHOTO_FILE = "temporary_holder.jpg"; private static final int REQ_CODE_PICK_IMAGE = 0; @Override public void onClick(View view) { try { //intent = new Intent(); // intent = new Intent(Intent.ACTION_PICK,android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI); Intent photoPickerIntent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI); //intent.setAction(Intent.ACTION_GET_CONTENT); photoPickerIntent.setType("image/*"); photoPickerIntent.putExtra("crop", "true"); photoPickerIntent.putExtra("scale", true); photoPickerIntent.putExtra("aspectX", 1); photoPickerIntent.putExtra("aspectY", 1); // indicate output X and Y photoPickerIntent.putExtra("outputX", 150); photoPickerIntent.putExtra("outputY", 100); photoPickerIntent.putExtra(MediaStore.EXTRA_OUTPUT, getTempUri()); photoPickerIntent.putExtra("outputFormat", Bitmap.CompressFormat.JPEG.toString()); startActivityForResult(photoPickerIntent, REQ_CODE_PICK_IMAGE); } catch (Exception e) { // Toast.makeText(getApplicationContext(), R.string.imageException, Toast.LENGTH_LONG).show(); Log.e(e.getClass().getName(), e.getMessage(), e); Toast toast = Toast.makeText(Upload_image_text.this, "This device doesn't support the crop action!", Toast.LENGTH_SHORT); toast.show(); } } private Uri getTempUri() { return Uri.fromFile(getTempFile()); } private File getTempFile() { if (isSDCARDMounted()) { File f = new File(Environment.getExternalStorageDirectory(),TEMP_PHOTO_FILE); try { f.createNewFile(); } catch (IOException e) { } return f; } else { return null; } } private boolean isSDCARDMounted(){ String status = Environment.getExternalStorageState(); if (status.equals(Environment.MEDIA_MOUNTED)) return true; return false; } }); 

=======================

 @Override 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) { if (imageReturnedIntent!=null){ // File tempFile = getTempFile(); ImagePath_1 = Environment.getExternalStorageDirectory() + "/temporary_holder.jpg"; System.out.println("path "+ImagePath_1); FixBitmap = BitmapFactory.decodeFile(ImagePath_1); ShowSelectedImage = (ImageView)findViewById(R.id.imageView); ShowSelectedImage.setImageBitmap(FixBitmap); } } } } 

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 @Override protected String doInBackground(Void... params) { BitmapFactory.Options options = new BitmapFactory.Options(); options.inSampleSize = 1; //options.outWidth = 50; //options.outHeight = 50; FixBitmap = BitmapFactory.decodeFile(ImagePath_1, options); //FixBitmap = BitmapFactory.decodeResource(getResources(), R.id.imageView); byteArrayOutputStream = new ByteArrayOutputStream(); FixBitmap.compress(Bitmap.CompressFormat.JPEG, 100, byteArrayOutputStream); //compress to 50% of original image quality byteArray = byteArrayOutputStream.toByteArray(); ConvertImage = Base64.encodeToString(byteArray, Base64.DEFAULT);