将android 7.0中FileProvider获取url的方法集成到插件库中

android/src/main/AndroidManifest.xml

 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.zt.shareextend">
+
+    <application>
+
+        <provider
+            android:name="android.support.v4.content.FileProvider"
+            android:authorities="com.zt.shareextend.fileprovider"
+            android:exported="false"
+            android:grantUriPermissions="true">
+            <meta-data
+                android:name="android.support.FILE_PROVIDER_PATHS"
+                android:resource="@xml/file_provider_path" />
+        </provider>
+
+    </application>
 </manifest>

android/src/main/java/com/zt/shareextend/ShareExtendPlugin.java

@@ -15,9 +15,13 @@ import android.support.v4.content.FileProvider;
 import java.io.File;
 import java.util.Map;
 
-/** Plugin method host for presenting a share sheet via Intent */
+/**
+ * Plugin method host for presenting a share sheet via Intent
+ */
 public class ShareExtendPlugin implements MethodChannel.MethodCallHandler {
 
+    private static final String authorities = "com.zt.shareextend.fileprovider";
+
     private static final String CHANNEL = "share_extend";
 
     public static void registerWith(Registrar registrar) {
@@ -39,14 +43,14 @@ public class ShareExtendPlugin implements MethodChannel.MethodCallHandler {
                 throw new IllegalArgumentException("Map argument expected");
             }
             // Android does not support showing the share sheet at a particular point on screen.
-      share((String) call.argument("text"),(String) call.argument("type"),(String) call.argument("authorities"));
+            share((String) call.argument("text"), (String) call.argument("type"));
             result.success(null);
         } else {
             result.notImplemented();
         }
     }
 
-  private void share(String text, String type,String authorities) {
+    private void share(String text, String type) {
         if (text == null || text.isEmpty()) {
             throw new IllegalArgumentException("Non-empty text expected");
         }
@@ -59,14 +63,14 @@ public class ShareExtendPlugin implements MethodChannel.MethodCallHandler {
             shareIntent.setType("text/plain");
         } else {
             File f = new File(text);
-      Uri uri = getUriForFile(mRegistrar.context(), authorities,f);
+            Uri uri = getUriForFile(mRegistrar.context(), f);
             if ("file".equals(type)) {
                 shareIntent.setType("application/*");
             }
             if ("image".equals(type)) {
                 shareIntent.setType("image/*");
             }
-      shareIntent.putExtra(Intent.EXTRA_STREAM,uri);
+            shareIntent.putExtra(Intent.EXTRA_STREAM, uri);
         }
 
         Intent chooserIntent = Intent.createChooser(shareIntent, null /* dialog title optional */);
@@ -78,9 +82,10 @@ public class ShareExtendPlugin implements MethodChannel.MethodCallHandler {
         }
     }
 
-  public static Uri getUriForFile(Context context, String authories, File file) {
+
+    public static Uri getUriForFile(Context context, File file) {
         if (Build.VERSION.SDK_INT >= 24) {
-      return FileProvider.getUriForFile(context, authories, file);
+            return FileProvider.getUriForFile(context, authorities, file);
         } else {
             return Uri.fromFile(file);
         }

example/android/app/src/main/res/xml/file_provider_path.xml → android/src/main/res/xml/file_provider_path.xml

 <?xml version="1.0" encoding="utf-8"?>
 <resources>
     <paths>
-        <external-path
-            name="external_cache"
-            path="" />
+        <root-path
+            name="root_path"
+            path="/" />
     </paths>
 </resources>
\ No newline at end of file

example/android/app/src/main/AndroidManifest.xml

@@ -6,6 +6,7 @@
          to allow setting breakpoints, to provide hot reload, etc.
     -->
     <uses-permission android:name="android.permission.INTERNET"/>
+    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
 
     <!-- io.flutter.app.FlutterApplication is an android.app.Application that
          calls FlutterMain.startInitialization(this); in its onCreate method.
@@ -36,15 +37,5 @@
             </intent-filter>
         </activity>
 
-        <provider
-            android:name="android.support.v4.content.FileProvider"
-            android:authorities="com.zt.shareextend.fileprovider"
-            android:grantUriPermissions="true"
-            android:exported="false">
-            <meta-data
-                android:name="android.support.FILE_PROVIDER_PATHS"
-                android:resource="@xml/file_provider_path" />
-        </provider>
-
     </application>
 </manifest>

example/lib/main.dart

@@ -3,6 +3,8 @@ import 'dart:io';
 
 import 'package:share_extend/share_extend.dart';
 import 'package:image_picker/image_picker.dart';
+import 'package:permission/permission.dart';
+import 'package:path_provider/path_provider.dart';
 
 void main() => runApp(new MyApp());
 
@@ -12,9 +14,6 @@ class MyApp extends StatefulWidget {
 }
 
 class _MyAppState extends State<MyApp> {
-  ///define in android project AndroidManifest.xml for FileProvider
-  static const String authorities = "com.zt.shareextend.fileprovider";
-
   @override
   void initState() {
     super.initState();
@@ -32,7 +31,7 @@ class _MyAppState extends State<MyApp> {
           children: <Widget>[
             new RaisedButton(
               onPressed: () {
-                ShareExtend.share("share text", "text", authorities);
+                ShareExtend.share("share text", "text");
               },
               child: new Text("share text"),
             ),
@@ -40,7 +39,7 @@ class _MyAppState extends State<MyApp> {
               onPressed: () async {
                 File f =
                     await ImagePicker.pickImage(source: ImageSource.gallery);
-                ShareExtend.share(f.path, "image", authorities);
+                ShareExtend.share(f.path, "image");
               },
               child: new Text("share image"),
             ),
@@ -48,13 +47,62 @@ class _MyAppState extends State<MyApp> {
               onPressed: () async {
                 File f =
                     await ImagePicker.pickImage(source: ImageSource.gallery);
-                ShareExtend.share(f.path, "file", authorities);
+                ShareExtend.share(f.path, "file");
               },
               child: new Text("share file"),
             ),
+            new RaisedButton(
+              onPressed: () {
+                if (Platform.isAndroid) {
+                  _shareFileWithPerm();
+                }
+              },
+              child: new Text("share android external storage file"),
+            ),
           ],
         )),
       ),
     );
   }
+
+  /// share the external storage file ,first check the permission
+  _shareFileWithPerm() async {
+    if (await _checkPermission()) {
+      _shareFile();
+    } else {
+      var result = await _requestPermission();
+
+      /// to ask for permission
+      if (result == PermissionStatus.allow) {
+        _shareFile();
+      }
+    }
+  }
+
+  /// create a test file for the share example
+  _shareFile() async {
+    String filePath = await _createTestFileToShare();
+    ShareExtend.share(filePath, "file");
+  }
+
+  ///create a test file to share
+  _createTestFileToShare() async {
+    Directory storageDir = await getExternalStorageDirectory();
+    File testFile = new File("${storageDir.path}/flutter/test.txt");
+    if (!await testFile.exists()) {
+      await testFile.create(recursive: true);
+    }
+    testFile.writeAsStringSync("test for share");
+    return testFile.path;
+  }
+
+  _checkPermission() async {
+    List<Permissions> perms =
+        await Permission.getPermissionStatus([PermissionName.Storage]);
+    return perms[0].permissionStatus == PermissionStatus.allow;
+  }
+
+  _requestPermission() async {
+    return await Permission.requestSinglePermission(PermissionName.Storage);
+  }
 }

example/pubspec.yaml

@@ -20,6 +20,8 @@ dependencies:
   # Use with the CupertinoIcons class for iOS style icons.
   cupertino_icons: ^0.1.2
   image_picker: ^0.4.10
+  path_provider: ^0.4.1
+  permission: ^0.1.0
 
 
 dev_dependencies:

lib/share_extend.dart

@@ -18,14 +18,13 @@ class ShareExtend {
   /// on iOS.
   /// type  "text", "image" ,"file"
   ///
-  static Future<void> share(String text, String type, String authorities,
+  static Future<void> share(String text, String type,
       {Rect sharePositionOrigin}) {
     assert(text != null);
     assert(text.isNotEmpty);
     final Map<String, dynamic> params = <String, dynamic>{
       'text': text,
-      'type': type,
-      'authorities': authorities
+      'type': type
     };
 
     if (sharePositionOrigin != null) {