尝试使用FileProvider获取URI时出现NullPointerException（Android）

Question

我想单击按钮后拍摄照片。但是当我试图获得URI和FileProvider时我得到NullPointerException。

这是我的错误码：

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.XmlResourceParser android.content.pm.PackageItemInfo.loadXmlMetaData(android.content.pm.PackageManager, java.lang.String)' on a null object reference 
     at android.support.v4.content.FileProvider.parsePathStrategy(FileProvider.java:583) 
    at android.support.v4.content.FileProvider.getPathStrategy(FileProvider.java:557) 
    at android.support.v4.content.FileProvider.getUriForFile(FileProvider.java:399) 

    at ibas.orosol.BildActivity.takePicture(BildActivity.java:86) 
    at java.lang.reflect.Method.invoke(Native Method)  
    at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288)  
    at android.view.View.performClick(View.java:5637)  
    at android.view.View$PerformClick.run(View.java:22429)  
    at android.os.Handler.handleCallback(Handler.java:751)  
    at android.os.Handler.dispatchMessage(Handler.java:95)  
    at android.os.Looper.loop(Looper.java:154)  
    at android.app.ActivityThread.main(ActivityThread.java:6119)  
    at java.lang.reflect.Method.invoke(Native Method)  
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)  
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776) 

的问题行似乎是：

mUri = FileProvider.getUriForFile(getApplication().getApplicationContext(), 
      "ibas.provider", file); 

Here's我码：

public void takePicture(View view) throws IOException { 

    Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE); 
    try{ 
     File file = createImageFile(); 

     mUri = FileProvider.getUriForFile(getApplication().getApplicationContext(), 
       "ibas.provider", file); 
     intent.putExtra(MediaStore.EXTRA_OUTPUT, mUri); 
     startActivityForResult(intent, REQUEST_IMAGE_CAPTURE); 
    } catch (IOException e){ 
     e.printStackTrace(); 
    } 

} 


private File createImageFile() throws IOException { 

    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date()); 
    String imageFileName = "JPEG_" + timeStamp + "_"; 
    File storageDir = getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM); 
    File image = File.createTempFile(
      imageFileName, /* prefix */ 
      ".jpg",   /* suffix */ 
      storageDir  /* directory */ 
    ); 

    // Save a file: path for use with ACTION_VIEW intents 
    mCurrentPhotoPath = "file:" + image.getAbsolutePath(); 
    return image; 
} 

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

    String path = "sdcard/orosol/captured_image.jpg"; 
    if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == Activity.RESULT_OK) { 
     Log.i("uri-data", "Uri: " + mUri.toString()); 


     mBitmap = getBitmapFromUri(mImageView,BildActivity.this,mUri); 


     mImageView.setImageBitmap(mBitmap); 
     mImageView.setScaleType(ImageView.ScaleType.CENTER_CROP); 

    } 

} 

我的清单：在res

<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
package="ibas.orosol"> 

<uses-permission android:name="android.permission.CAMERA" /> 
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" /> 
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> 
<uses-permission android:name="android.permission.INTERNET" /> 
<uses-permission android:name="android.permission.CALL_PHONE" /> 

<uses-feature 
    android:name="android.hardware.camera" 
    android:required="false" /> 

<provider 
    android:name="android.support.v4.content.FileProvider" 
    android:authorities="ibas.provider" 
    android:exported="false" 
    android:grantUriPermissions="true"> 
    <meta-data 
     android:name="android.support.FILE_PROVIDER_PATHS" 
     android:resource="@xml/provider_paths" /> 
</provider> 

<!-- 
    The ACCESS_COARSE/FINE_LOCATION permissions are not required to use 
    Google Maps Android API v2, but you must specify either coarse or fine 
    location permissions for the 'MyLocation' functionality. 
--> 
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> 

<application 
    android:allowBackup="true" 
    android:icon="@mipmap/ic_launcher" 
    android:label="@string/app_name" 
    android:roundIcon="@mipmap/ic_launcher_round" 
    android:supportsRtl="true" 
    android:theme="@style/Theme.AppCompat.NoActionBar"> 
    <activity android:name=".MainActivity"> 
     <intent-filter> 
      <action android:name="android.intent.action.MAIN" /> 

      <category android:name="android.intent.category.LAUNCHER" /> 
     </intent-filter> 
    </activity> 
    <activity android:name=".MenuActivity" /> 
    <activity 
     android:name=".HeizoelActivity" 
     android:theme="@style/AppTheme"> 
     <meta-data 
      android:name="android.support.PARENT_ACTIVITY" 
      android:value=".MenuActivity" /> 
    </activity> 
    <activity 
     android:name=".BildActivity" 
     android:theme="@style/AppTheme"> 
     <meta-data 
      android:name="android.support.PARENT_ACTIVITY" 
      android:value=".MenuActivity" /> 
     > 
    </activity> 
    <activity 
     android:name=".FacebookActivity" 
     android:theme="@style/AppTheme"> 
     <meta-data 
      android:name="android.support.PARENT_ACTIVITY" 
      android:value=".MenuActivity" /> 
    </activity> 
    <!-- 
     The API key for Google Maps-based APIs is defined as a string resource. 
     (See the file "res/values/google_maps_api.xml"). 
     Note that the API key is linked to the encryption key used to sign the APK. 
     You need a different API key for each encryption key, including the release key that is used to 
     sign the APK for publishing. 
     You can define the keys for the debug and release targets in src/debug/ and src/release/. 
    --> 
    <meta-data 
     android:name="com.google.android.geo.API_KEY" 
     android:value="@string/google_maps_key" /> 

    <activity 
     android:name=".KontakteActivity" 
     android:theme="@style/AppTheme"> 
     <meta-data 
      android:name="android.support.PARENT_ACTIVITY" 
      android:value=".MenuActivity" /> 
    </activity> 
    <activity android:name=".UeberUnsActivity" 
     android:theme="@style/AppTheme"> 
     <meta-data 
      android:name="android.support.PARENT_ACTIVITY" 
      android:value=".MenuActivity" /> 
    </activity> 
</application> 

提供商/ XML

<paths xmlns:android="http://schemas.android.com/apk/res/android"> 
<external-path name="external_files" path="."/> </paths> 

任何想法，其中发生问题时S'

Answer 1

提供者标记位于清单文件中应用程序标记的外部。

您应该添加它<application></application>标签内

<provider 
    android:name="android.support.v4.content.FileProvider" 
    android:authorities="ibas.provider" 
    android:exported="false" 
    android:grantUriPermissions="true"> 
    <meta-data 
     android:name="android.support.FILE_PROVIDER_PATHS" 
     android:resource="@xml/provider_paths" /> 
</provider>