我有“用相机捕获图像”的问题,并将其存储到Firebase中.我认为该代码是正确的,因为它可以与“从图库中选择图像”一起使用.捕获完图像后,该应用程序停止了,并且没有存储在数据库中.我认为这对于android M和N是个问题.我只是看到其他类似的问题,但它们对我不起作用.我为此寻求帮助,因为我不知道解决方案.谢谢. logcat中也存在错误.
@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();
}
});
}}
日志猫：
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method ‘java.lang.String .Uri.getLastPathSegment()’ on a null object reference
解决方法:
对于您的问题,我有一个答案,因为几天前我做了同样的事情.问题在于您的Uri无法获得应有的图像,因此您需要为捕获的图像创建自己的Uri.
对于您的应用,您还可以将以下代码复制并粘贴到您的主要活动中：
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();
}
});
}
}
}
并确保您遵循文档并在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">
还有res / xml / file_paths.xml(您只需在“ res”文件夹下创建一个目录,并将其命名为xml,然后创建一个资源文件,并将其命名为file_paths.xml)；然后删除其中的所有代码(会有几行)并粘贴以下内容：
确保将com.serjardovic.firebasesandbox更改为您自己的包名称！
效果100％-玩得开心！
标签：firebase,camera,firebase-storage,android,image-uploading
来源： https://codeday.me/bug/1026/1937019.html
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 .Uri.getLastPathSegment()’...
