feat(dialog): add `showFolderPicker` to android

plugins/dialog/android/src/main/java/DialogPlugin.kt

@@ -47,6 +47,14 @@ class SaveFileDialogOptions {
   lateinit var filters: Array<Filter>
 }
 
+@InvokeArg
+class FolderPickerOptions {
+  var title: String? = null
+  var multiple: Boolean? = null
+  var recursive: Boolean? = null
+  var canCreateDirectories: Boolean? = null
+}
+
 @TauriPlugin
 class DialogPlugin(private val activity: Activity): Plugin(activity) {
   var filePickerOptions: FilePickerOptions? = null
@@ -249,4 +257,55 @@ class DialogPlugin(private val activity: Activity): Plugin(activity) {
       invoke.reject(message)
     }
   }
+
+  @Command
+  fun showFolderPicker(invoke: Invoke) {
+    try {
+      val args = invoke.parseArgs(FolderPickerOptions::class.java)
+      val intent = Intent(Intent.ACTION_OPEN_DOCUMENT_TREE)
+      
+      if (args.title != null) {
+        intent.putExtra(Intent.EXTRA_TITLE, args.title)
+      }
+      
+      // Note: Android's document tree picker doesn't support multiple selection natively
+      // recursive and canCreateDirectories are handled at filesystem level
+      
+      startActivityForResult(invoke, intent, "folderPickerResult")
+    } catch (ex: Exception) {
+      val message = ex.message ?: "Failed to pick folder"
+      Logger.error(message)
+      invoke.reject(message)
+    }
+  }
+
+  @ActivityCallback
+  fun folderPickerResult(invoke: Invoke, result: ActivityResult) {
+    try {
+      when (result.resultCode) {
+        Activity.RESULT_OK -> {
+          val callResult = createFolderPickerResult(result.data)
+          invoke.resolve(callResult)
+        }
+        Activity.RESULT_CANCELED -> invoke.reject("Folder picker cancelled")
+        else -> invoke.reject("Failed to pick folder")
+      }
+    } catch (ex: java.lang.Exception) {
+      val message = ex.message ?: "Failed to read folder pick result"
+      Logger.error(message)
+      invoke.reject(message)
+    }
+  }
+
+  private fun createFolderPickerResult(data: Intent?): JSObject {
+    val callResult = JSObject()
+    if (data == null) {
+      callResult.put("directories", null)
+      return callResult
+    }
+    val uri = data.data
+    val directories = JSArray.from(arrayOf(uri.toString()))
+    callResult.put("directories", directories)
+    return callResult
+  }
 }

plugins/dialog/android/src/main/java/FilePickerUtils.kt

@@ -198,6 +198,22 @@ class FilePickerUtils {
       }
       return os.toByteArray()
     }
+
+    private fun isTreeUri(uri: Uri): Boolean {
+      return DocumentsContract.isTreeUri(uri)
+    }
+
+    fun getTreePathFromUri(context: Context, uri: Uri): String? {
+      if (!isTreeUri(uri)) return null
+      
+      val docId = DocumentsContract.getTreeDocumentId(uri)
+      val split = docId.split(":")
+      return if ("primary".equals(split[0], ignoreCase = true)) {
+        "${Environment.getExternalStorageDirectory()}/${split[1]}"
+      } else {
+        null
+      }
+    }
   }
 }
 

plugins/dialog/src/commands.rs

@@ -16,9 +16,9 @@ use crate::{
 #[derive(Serialize)]
 #[serde(untagged)]
 pub enum OpenResponse {
-    #[cfg(any(desktop, target_os = "ios"))]
+    #[cfg(any(desktop, target_os = "ios", target_os = "android"))]
     Folders(Option<Vec<FilePath>>),
-    #[cfg(any(desktop, target_os = "ios"))]
+    #[cfg(any(desktop, target_os = "ios", target_os = "android"))]
     Folder(Option<FilePath>),
     Files(Option<Vec<FilePath>>),
     File(Option<FilePath>),
@@ -132,8 +132,8 @@ pub(crate) async fn open<R: Runtime>(
         dialog_builder = dialog_builder.add_filter(filter.name, &extensions);
     }
 
-    let res = if options.directory {
+    if options.directory {
-        #[cfg(any(desktop, target_os = "ios"))]
+        #[cfg(any(desktop, target_os = "ios", target_os = "android"))]
         {
             let tauri_scope = window.state::<tauri::scope::Scopes>();
 
@@ -149,9 +149,9 @@ pub(crate) async fn open<R: Runtime>(
                         }
                     }
                 }
-                OpenResponse::Folders(
+                return Ok(OpenResponse::Folders(
                     folders.map(|folders| folders.into_iter().map(|p| p.simplified()).collect()),
-                )
+                ));
             } else {
                 let folder = dialog_builder.blocking_pick_folder();
                 if let Some(folder) = &folder {
@@ -162,14 +162,14 @@ pub(crate) async fn open<R: Runtime>(
                         tauri_scope.allow_directory(&path, options.directory)?;
                     }
                 }
-                OpenResponse::Folder(folder.map(|p| p.simplified()))
+                return Ok(OpenResponse::Folder(folder.map(|p| p.simplified())));
+            }
         }
     }
-        #[cfg(all(mobile, not(target_os = "ios")))]
-        return Err(crate::Error::FolderPickerNotImplemented);
-    } else if options.multiple {
-        let tauri_scope = window.state::<tauri::scope::Scopes>();
 
+    // Handle file selection
+    if options.multiple {
+        let tauri_scope = window.state::<tauri::scope::Scopes>();
         let files = dialog_builder.blocking_pick_files();
         if let Some(files) = &files {
             for file in files {
@@ -177,16 +177,14 @@ pub(crate) async fn open<R: Runtime>(
                     if let Some(s) = window.try_fs_scope() {
                         s.allow_file(&path)?;
                     }
-
                     tauri_scope.allow_file(&path)?;
                 }
             }
         }
-        OpenResponse::Files(files.map(|files| files.into_iter().map(|f| f.simplified()).collect()))
+        Ok(OpenResponse::Files(files.map(|files| files.into_iter().map(|f| f.simplified()).collect())))
     } else {
         let tauri_scope = window.state::<tauri::scope::Scopes>();
         let file = dialog_builder.blocking_pick_file();
-
         if let Some(file) = &file {
             if let Ok(path) = file.clone().into_path() {
                 if let Some(s) = window.try_fs_scope() {
@@ -195,9 +193,8 @@ pub(crate) async fn open<R: Runtime>(
                 tauri_scope.allow_file(&path)?;
             }
         }
-        OpenResponse::File(file.map(|f| f.simplified()))
+        Ok(OpenResponse::File(file.map(|f| f.simplified())))
-    };
+    }
-    Ok(res)
 }
 
 #[allow(unused_variables)]

plugins/dialog/src/error.rs

@@ -16,9 +16,6 @@ pub enum Error {
     #[cfg(mobile)]
     #[error(transparent)]
     PluginInvoke(#[from] tauri::plugin::mobile::PluginInvokeError),
-    #[cfg(mobile)]
-    #[error("Folder picker is not implemented on mobile")]
-    FolderPickerNotImplemented,
     #[error(transparent)]
     Fs(#[from] tauri_plugin_fs::Error),
 }

plugins/dialog/src/lib.rs

@@ -506,7 +506,7 @@ impl<R: Runtime> FileDialogBuilder<R> {
     ///     Ok(())
     ///   });
     /// ```
-    #[cfg(any(desktop, target_os = "ios"))]
+    #[cfg(any(desktop, target_os = "ios", target_os = "android"))]
     pub fn pick_folder<F: FnOnce(Option<FilePath>) + Send + 'static>(self, f: F) {
         pick_folder(self, f)
     }
@@ -528,7 +528,7 @@ impl<R: Runtime> FileDialogBuilder<R> {
     ///     Ok(())
     ///   });
     /// ```
-    #[cfg(any(desktop, target_os = "ios"))]
+    #[cfg(any(desktop, target_os = "ios", target_os = "android"))]
     pub fn pick_folders<F: FnOnce(Option<Vec<FilePath>>) + Send + 'static>(self, f: F) {
         pick_folders(self, f)
     }
@@ -611,7 +611,7 @@ impl<R: Runtime> FileDialogBuilder<R> {
     ///   // the folder path is `None` if the user closed the dialog
     /// }
     /// ```
-    #[cfg(any(desktop, target_os = "ios"))]
+    #[cfg(any(desktop, target_os = "ios", target_os = "android"))]
     pub fn blocking_pick_folder(self) -> Option<FilePath> {
         blocking_fn!(self, pick_folder)
     }
@@ -631,7 +631,7 @@ impl<R: Runtime> FileDialogBuilder<R> {
     ///   // the folder paths value is `None` if the user closed the dialog
     /// }
     /// ```
-    #[cfg(any(desktop, target_os = "ios"))]
+    #[cfg(any(desktop, target_os = "ios", target_os = "android"))]
     pub fn blocking_pick_folders(self) -> Option<Vec<FilePath>> {
         blocking_fn!(self, pick_folders)
     }

plugins/dialog/src/mobile.rs

@@ -131,7 +131,7 @@ pub fn show_message_dialog<R: Runtime, F: FnOnce(bool) + Send + 'static>(
     });
 }
 
-#[cfg(target_os = "ios")]
+#[cfg(mobile)]
 pub fn pick_folders<R: Runtime, F: FnOnce(Option<Vec<FilePath>>) + Send + 'static>(
     dialog: FileDialogBuilder<R>,
     f: F,
@@ -149,7 +149,7 @@ pub fn pick_folders<R: Runtime, F: FnOnce(Option<Vec<FilePath>>) + Send + 'stati
     });
 }
 
-#[cfg(target_os = "ios")]
+#[cfg(mobile)]
 pub fn pick_folder<R: Runtime, F: FnOnce(Option<FilePath>) + Send + 'static>(
     dialog: FileDialogBuilder<R>,
     f: F,