我有“用相機(jī)捕獲圖像”的問題,并將其存儲(chǔ)到Firebase中.我認(rèn)為該代碼是正確的,因?yàn)樗梢耘c“從圖庫中選擇圖像”一起使用.捕獲完圖像后,該應(yīng)用程序停止了,并且沒有存儲(chǔ)在數(shù)據(jù)庫中.我認(rèn)為這對(duì)于android M和N是個(gè)問題.我只是看到其他類似的問題,但它們對(duì)我不起作用.我為此尋求幫助,因?yàn)槲也恢澜鉀Q方案.謝謝. logcat中也存在錯(cuò)誤.

@Override

protected void onActivityResult(int requestCode, int resultCode, Intent data) {

super.onActivityResult(requestCode, resultCode, data);

if (requestCode == CAMERA_REQUEST_CODE && resultCode == RESULT_OK){

mPregresDialog.setMessage("Uploading...");

mPregresDialog.show();

Uri uri = data.getData();

StorageReference filepath = mStorage.child("Photo").child(uri.getLastPathSegment());

filepath.putFile(uri).addOnSuccessListener(new OnSuccessListener() {

@Override

public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {

mPregresDialog.dismiss();

Toast.makeText(MainActivity.this, "Upload Done", Toast.LENGTH_LONG).show();

}

});

}}

日志貓：

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method ‘java.lang.String android.net.Uri.getLastPathSegment()’ on a null object reference

解決方法:

對(duì)于您的問題,我有一個(gè)答案,因?yàn)閹滋烨拔易隽送瑯拥氖虑?問題在于您的Uri無法獲得應(yīng)有的圖像,因此您需要為捕獲的圖像創(chuàng)建自己的Uri.

對(duì)于您的應(yīng)用,您還可以將以下代碼復(fù)制并粘貼到您的主要活動(dòng)中：

String mCurrentPhotoPath;

private File createImageFile() throws IOException {

// Create an image file name

String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());

String imageFileName = "JPEG_" + timeStamp + "_";

File storageDir = getExternalFilesDir(Environment.DIRECTORY_PICTURES);

File image = File.createTempFile(

imageFileName, /* prefix */

".jpg", /* suffix */

storageDir /* directory */

);

// Save a file: path for use with ACTION_VIEW intents

mCurrentPhotoPath = image.getAbsolutePath();

return image;

}

private void dispatchTakePictureIntent() {

Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

// Ensure that there's a camera activity to handle the intent

if (takePictureIntent.resolveActivity(getPackageManager()) != null) {

// Create the File where the photo should go

File photoFile = null;

try {

photoFile = createImageFile();

} catch (IOException ex) {

// Error occurred while creating the File...

}

// Continue only if the File was successfully created

if (photoFile != null) {

Uri photoURI = FileProvider.getUriForFile(this,

"com.example.android.fileprovider",

photoFile);

takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);

startActivityForResult(takePictureIntent, CAMERA_REQUEST_CODE);

}

}

}

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

storage = FirebaseStorage.getInstance().getReference();

b_gallery = (Button) findViewById(R.id.b_gallery);

b_capture = (Button) findViewById(R.id.b_capture);

iv_image = (ImageView) findViewById(R.id.iv_image);

progressDialog = new ProgressDialog(this);

b_capture.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

//Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

dispatchTakePictureIntent();

}

});

}

@Override

protected void onActivityResult(int requestCode, int resultCode, Intent data) {

super.onActivityResult(requestCode, resultCode, data);

if(requestCode == CAMERA_REQUEST_CODE && resultCode == RESULT_OK){

progressDialog.setMessage("Uploading...");

progressDialog.show();

Uri uri = data.getData();

StorageReference filepath = storage.child("Photos").child(uri.getLastPathSegment());

filepath.putFile(photoURI).addOnSuccessListener(new OnSuccessListener() {

@Override

public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {

Toast.makeText(MainActivity.this, "Upload Successful!", Toast.LENGTH_SHORT).show();

progressDialog.dismiss();

}

}).addOnFailureListener(new OnFailureListener() {

@Override

public void onFailure(@NonNull Exception e) {

Toast.makeText(MainActivity.this, "Upload Failed!", Toast.LENGTH_SHORT).show();

}

});

}

}

}

并確保您遵循文檔并在AndroidManifest.xml中添加了提供程序：

android:name="android.support.v4.content.FileProvider"

android:authorities="com.example.android.fileprovider"

android:exported="false"

android:grantUriPermissions="true">

android:name="android.support.FILE_PROVIDER_PATHS"

android:resource="@xml/file_paths">

還有res / xml / file_paths.xml(您只需在“ res”文件夾下創(chuàng)建一個(gè)目錄,并將其命名為xml,然后創(chuàng)建一個(gè)資源文件,并將其命名為file_paths.xml)；然后刪除其中的所有代碼(會(huì)有幾行)并粘貼以下內(nèi)容：

確保將com.serjardovic.firebasesandbox更改為您自己的包名稱！

效果100％-玩得開心！

標(biāo)簽：firebase,camera,firebase-storage,android,image-uploading

來源： https://codeday.me/bug/20191026/1937019.html

總結(jié)

以上是生活随笔為你收集整理的java对象引用出错_上传图片错误：尝试在空对象引用上调用虚拟方法’java.lang.String android.net.Uri.getLastPathSegment()’...的全部內(nèi)容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網(wǎng)站內(nèi)容還不錯(cuò)，歡迎將生活随笔推薦給好友。