我是android的新手，我遇到了一个奇怪的问题......
我正在尝试修改Google提供的WifiDirectDemo，更具体地说，该演示为我们提供了选择我想要传输的图像的自由，但我只是想让它传输特定的图像。原始代码如下：
public class DeviceDetailFragment extends Fragment implements ConnectionInfoListener {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
mContentView = inflater.inflate(R.layout.device_detail, null);
mContentView.findViewById(R.id.btn_start_client).setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
// Allow user to pick an image from Gallery or other
// registered apps
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
startActivityForResult(intent, CHOOSE_FILE_RESULT_CODE);
}
});
return mContentView;
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
// User has picked an image. Transfer it to group owner i.e peer using
// FileTransferService.
Uri uri = data.getData();
TextView statusText = (TextView) mContentView.findViewById(R.id.status_text);
statusText.setText("Sending: " + uri);
Log.d(WiFiDirectActivity.TAG, "Intent----------- " + uri);
Intent serviceIntent = new Intent(getActivity(), FileTransferService.class);
serviceIntent.setAction(FileTransferService.ACTION_SEND_FILE);
serviceIntent.putExtra(FileTransferService.EXTRAS_FILE_PATH, uri.toString());
serviceIntent.putExtra(FileTransferService.EXTRAS_GROUP_OWNER_ADDRESS,
info.groupOwnerAddress.getHostAddress());
serviceIntent.putExtra(FileTransferService.EXTRAS_GROUP_OWNER_PORT, 8988);
getActivity().startService(serviceIntent);
}
它完全正常。但是在我将onActivityResult方法的代码移动到onClick方法之后，我在运行时遇到了一些错误。这是我的代码。
@Override
public void onClick(View v) {
// Allow user to pick an image from Gallery or other
// registered apps
String uristring = "content://com.android.providers.media.documents/document/image%3A25";
Intent serviceIntent = new Intent(getActivity(), FileTransferService.class);
serviceIntent.setAction(FileTransferService.ACTION_SEND_FILE);
serviceIntent.putExtra(FileTransferService.EXTRAS_FILE_PATH, uristring);
serviceIntent.putExtra(FileTransferService.EXTRAS_GROUP_OWNER_ADDRESS,
info.groupOwnerAddress.getHostAddress());
serviceIntent.putExtra(FileTransferService.EXTRAS_GROUP_OWNER_PORT, 8988);
getActivity().startService(serviceIntent);
}
错误代码如下：
11-15 00:11:16.397: W/dalvikvm(18595): threadid=11: thread exiting with uncaught exception (group=0x41553b90)
11-15 00:11:16.397: E/AndroidRuntime(18595): FATAL EXCEPTION: IntentService[FileTransferService]
11-15 00:11:16.397: E/AndroidRuntime(18595): Process: com.example.android.wifidirect, PID: 18595
11-15 00:11:16.397: E/AndroidRuntime(18595): java.lang.SecurityException: Permission Denial: opening provider com.android.providers.media.MediaDocumentsProvider from ProcessRecord{42a042a8 18595:com.example.android.wifidirect/u0a77} (pid=18595, uid=10077) requires android.permission.MANAGE_DOCUMENTS or android.permission.MANAGE_DOCUMENTS
11-15 00:11:16.397: E/AndroidRuntime(18595): at android.os.Parcel.readException(Parcel.java:1461)
11-15 00:11:16.397: E/AndroidRuntime(18595): at android.os.Parcel.readException(Parcel.java:1415)
11-15 00:11:16.397: E/AndroidRuntime(18595): at android.app.ActivityManagerProxy.getContentProvider(ActivityManagerNative.java:2848)
11-15 00:11:16.397: E/AndroidRuntime(18595): at android.app.ActivityThread.acquireProvider(ActivityThread.java:4396)
11-15 00:11:16.397: E/AndroidRuntime(18595): at android.app.ContextImpl$ApplicationContentResolver.acquireUnstableProvider(ContextImpl.java:2207)
11-15 00:11:16.397: E/AndroidRuntime(18595): at android.content.ContentResolver.acquireUnstableProvider(ContentResolver.java:1425)
11-15 00:11:16.397: E/AndroidRuntime(18595): at android.content.ContentResolver.openTypedAssetFileDescriptor(ContentResolver.java:1047)
11-15 00:11:16.397: E/AndroidRuntime(18595): at android.content.ContentResolver.openAssetFileDescriptor(ContentResolver.java:904)
11-15 00:11:16.397: E/AndroidRuntime(18595): at android.content.ContentResolver.openInputStream(ContentResolver.java:629)
11-15 00:11:16.397: E/AndroidRuntime(18595): at com.example.android.wifidirect.FileTransferService.onHandleIntent(FileTransferService.java:63)
11-15 00:11:16.397: E/AndroidRuntime(18595): at android.app.IntentService$ServiceHandler.handleMessage(IntentService.java:65)
11-15 00:11:16.397: E/AndroidRuntime(18595): at android.os.Handler.dispatchMessage(Handler.java:102)
11-15 00:11:16.397: E/AndroidRuntime(18595): at android.os.Looper.loop(Looper.java:137)
11-15 00:11:16.397: E/AndroidRuntime(18595): at android.os.HandlerThread.run(HandlerThread.java:61)
有人可以提供帮助吗？
更新
我向清单添加了权限，以下是清单的样子：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.android.wifidirect"
android:versionCode="1" android:versionName="1.0">
<uses-sdk android:minSdkVersion="14" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.MANAGE_DOCUMENTS"/>
<!-- Google Play filtering -->
<uses-feature android:name="android.hardware.wifi.direct" android:required="true"/>
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@android:style/Theme.Holo">
<activity
android:name=".WiFiDirectActivity"
android:label="@string/app_name" android:launchMode="singleTask">
<intent-filter>
<action
android:name="android.intent.action.MAIN" />
<category
android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<!-- Used for transferring files after a successful connection -->
<service android:enabled="true" android:name=".FileTransferService" />
</application>
该应用程序仍然崩溃并显示相同的错误信息。
但是当我运行以下代码时，不会发生错误。
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
mContentView = inflater.inflate(R.layout.device_detail, null);
mContentView.findViewById(R.id.btn_start_client).setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
// Allow user to pick an image from Gallery or other
// registered apps
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
startActivityForResult(intent, CHOOSE_FILE_RESULT_CODE);
}
});
return mContentView;
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
// User has picked an image. Transfer it to group owner i.e peer using
String uristring = "content://com.android.providers.media.documents/document/image%3A25";
Intent serviceIntent = new Intent(getActivity(), FileTransferService.class);
serviceIntent.setAction(FileTransferService.ACTION_SEND_FILE);
serviceIntent.putExtra(FileTransferService.EXTRAS_FILE_PATH, uristring);
serviceIntent.putExtra(FileTransferService.EXTRAS_GROUP_OWNER_ADDRESS,
info.groupOwnerAddress.getHostAddress());
serviceIntent.putExtra(FileTransferService.EXTRAS_GROUP_OWNER_PORT, 8988);
getActivity().startService(serviceIntent);
}
因此，当我将onActivityResult的行序列移动到onClick时会发生错误。我只是不知道情况是什么，因为实际上我已经向清单添加了MANAGE_DOCUMENT权限，并且它一直在寻求许可。如果没有manifest中的权限，如果我将代码放回onActivityResult，我仍然可以访问图像文件。有谁知道为什么？非常感谢你！
答案 0 :(得分：0)
在清单中声明权限
<uses-permission android:name="android.permission.MANAGE_DOCUMENTS"/>
答案 1 :(得分：0)
我认为您在清单文件中缺少某些权限 在清单文件中添加
阅读此文档https://developer.android.com/guide/topics/providers/document-provider.html
<uses-permission android:name="android.permission.MANAGE_DOCUMENTS"/>
答案 2 :(得分：0)
您需要在清单中添加以下权限
<uses-permission android:name="android.permission.MANAGE_DOCUMENTS"/>