我正在尝试访问UARTlogfragment.java中AndroidManifest.xml中声明的全局变量，但使用getApplication()时出现错误，即“无法解析”。
我在这里发布我的Androidmanifest.xml和UARTlogfragment.java。
AndroidManifest.xml是：
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.NFC" />
<uses-permission android:name="no.nordicsemi.android.LOG" />
<uses-feature
android:name="android.hardware.bluetooth_le"
android:required="true" />
<!-- To auto-complete the email text field in the login form with the user's emails -->
<uses-permission android:name="android.permission.GET_ACCOUNTS" />
<uses-permission android:name="android.permission.READ_PROFILE" />
<uses-permission android:name="android.permission.READ_CONTACTS" />
<application
android:name=".ToolboxApplication"
android:allowBackup="true"
android:fullBackupContent="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:theme="@style/AppTheme"
tools:ignore="GoogleAppIndexingWarning">
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
<activity
android:name=".SplashscreenActivity"
android:label="@string/app_name"
android:theme="@style/AppTheme.Fullscreen">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<meta-data
android:name="android.app.shortcuts"
android:resource="@xml/shortcuts" />
<intent-filter>
<action android:name="android.nfc.action.NDEF_DISCOVERED" />
<category android:name="android.intent.category.DEFAULT" />
<data android:mimeType="application/vnd.no.nordicsemi.type.app" />
<data android:mimeType="application/vnd.no.nordicsemi.type.address" />
</intent-filter>
</activity>
<!-- Template plugin activities -->
<!-- Remember to add your plug-in Activities to the Android Manifest file. -->
<!-- Plug-in activities -->
<activity
android:name=".FeaturesActivity"
android:label="@string/app_name"
android:launchMode="singleTask"
android:theme="@style/AppTheme.TranslucentStatusBar" />
<activity
android:name=".uart.UARTActivity"
android:icon="@drawable/ic_uart_feature"
android:label="@string/uart_feature_title"
android:launchMode="singleTask"
android:windowSoftInputMode="adjustResize">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="no.nordicsemi.android.nrftoolbox.LAUNCHER" />
</intent-filter>
</activity>
<service
android:name=".proximity.ProximityService"
android:label="@string/proximity_feature_title" />
<service
android:name=".dfu.DfuService"
android:exported="true"
android:label="@string/dfu_service_title">
<intent-filter>
<action android:name="no.nordicsemi.android.action.DFU_UPLOAD" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</service>
<activity
android:name=".dfu.DfuInitiatorActivity"
android:label="@string/dfu_service_title"
android:noHistory="true"
android:theme="@style/AppTheme.Translucent">
<intent-filter>
<action android:name="no.nordicsemi.android.action.DFU_UPLOAD" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<service
android:name=".cgms.CGMService"
android:label="@string/cgms_feature_title" />
<service
android:name=".rsc.RSCService"
android:label="@string/rsc_feature_title" />
<service
android:name=".csc.CSCService"
android:label="@string/csc_feature_title" />
<service
android:name=".hts.HTSService"
android:label="@string/hts_feature_title" />
<service
android:name=".uart.UARTService"
android:label="@string/uart_feature_title" />
<service android:name=".wearable.MainWearableListenerService">
<intent-filter>
<action android:name="com.google.android.gms.wearable.DATA_CHANGED" />
<action android:name="com.google.android.gms.wearable.MESSAGE_RECEIVED" />
<data
android:host="*"
android:pathPrefix="/nrftoolbox"
android:scheme="wear" />
</intent-filter>
</service>
<provider
android:name=".uart.UARTLocalLogContentProvider"
android:authorities="no.nordicsemi.android.nrftoolbox.uart.log"
android:exported="true" />
<activity
android:name=".Register_Page"
android:label="@string/title_activity_register__page" />
<activity android:name=".View_Profile" />
<activity android:name=".Profile" />
<activity android:name=".Wallet_Page" />
<activity android:name=".confirm_booking" />
<activity android:name=".LoginActivity" />
<activity android:name=".Add_Amount" />
<activity android:name=".last_step_book"></activity>
</application>
UARTlogfragment.java（我试图访问全局变量的地方）是：
public View onCreateView(final LayoutInflater inflater, final ViewGroup container, final Bundle savedInstanceState) {
final View view = inflater.inflate(R.layout.fragment_feature_uart_log, container, false);
mydb = new no.nordicsemi.android.nrftoolbox.myDbAdapter(getContext());
String s = ((ToolboxApplication) this.getApplication()).getSomeVariable();
Cursor rs = mydb.getData(1);
rs.moveToFirst();
String nam = rs.getString(rs.getColumnIndex(no.nordicsemi.android.nrftoolbox.myDbAdapter.CONTACTS_COLUMN_NAME));
String phon = rs.getString(rs.getColumnIndex(no.nordicsemi.android.nrftoolbox.myDbAdapter.CONTACTS_COLUMN_PHONE));
String emai = rs.getString(rs.getColumnIndex(no.nordicsemi.android.nrftoolbox.myDbAdapter.CONTACTS_COLUMN_EMAIL));
String cit = rs.getString(rs.getColumnIndex(no.nordicsemi.android.nrftoolbox.myDbAdapter.CONTACTS_COLUMN_CITY));
String gend = rs.getString(rs.getColumnIndex(no.nordicsemi.android.nrftoolbox.myDbAdapter.CONTACTS_COLUMN_GENDER));
String pas = rs.getString(rs.getColumnIndex(no.nordicsemi.android.nrftoolbox.myDbAdapter.CONTACTS_COLUMN_PASS));
String dobb = rs.getString(rs.getColumnIndex(no.nordicsemi.android.nrftoolbox.myDbAdapter.CONTACTS_COLUMN_DOB));
if (!rs.isClosed()) {
rs.close();
}
final EditText field = mField = view.findViewById(R.id.field);
mField.setText(nam+" "+emai+" "+phon+" "+gend+" "+cit);
field.setOnEditorActionListener((v, actionId, event) -> {
if (actionId == EditorInfo.IME_ACTION_SEND) {
onSendClicked();
return true;
}
return false;
});
final Button sendButton = mSendButton = view.findViewById(R.id.action_send);
sendButton.setOnClickListener(v -> onSendClicked());
return view;
}
错误是什么？为什么它不能解决getApplication() ??
答案 0 :(得分：1)
更改
String s = ((ToolboxApplication) this.getApplication()).getSomeVariable();
到
String s = ((ToolboxApplication) getActivity().getApplication()).getSomeVariable();
答案 1 :(得分：1)
当您尝试使用片段中的应用程序上下文时，您无法使用getApplication()，因为Fragment类的isn＆t方法
因此，您首先必须使用getActivity()，它将返回片段当前与之关联的片段活动。
总结你的代码，
而不是this.getApplication()您必须使用getActivity.getApplication()