Add support for opening folders.

This does open mobile pickers as well, though the lack of ListableURI in mobile means it does not return correctly.

Fixes fyne-io#941

CHANGELOG.md

@@ -8,7 +8,7 @@ More detailed release notes can be found on the [releases page](https://github.c
 ### Added (highlights)
 
 * List (#156), Table (#157) and Tree collection Widgets
-* Card, FileItem widgets
+* Card, FileItem, Separator widgets
 * ColorPicker dialog
 * User selection of primary colour
 * Container API package to ease using layouts and container widgets
@@ -20,6 +20,7 @@ More detailed release notes can be found on the [releases page](https://github.c
 * Canvas.InteractiveArea() to indicate where widgets should avoid
 * TextFormatter for ProgressBar
 * FileDialog.SetLocation() (#821)
+* Added dialog.ShowFolderOpen (#941)
 * Support to install on iOS and android with 'fyne install'
 * Support asset bundling with go:generate
 * Add fyne release command for preparing signed apps

cmd/fyne_demo/screens/window.go

@@ -172,6 +172,18 @@ func loadDialogGroup(win fyne.Window) *widget.Card {
 				fileSaved(writer)
 			}, win)
 		}),
+		widget.NewButton("Folder Open", func() {
+			dialog.ShowFolderOpen(func(list fyne.ListableURI, err error) {
+				if list == nil {
+					return
+				}
+				if err != nil {
+					dialog.ShowError(err, win)
+					return
+				}
+				dialog.ShowInformation("Folder Open", list.String(), win)
+			}, win)
+		}),
 		widget.NewButton("Color Picker", func() {
 			picker := dialog.NewColorPicker("Pick a Color", "What is your favorite color?", func(c color.Color) {
 				colorPicked(c, win)

dialog/file.go

@@ -120,6 +120,13 @@ func (f *fileDialog) makeUI() fyne.CanvasObject {
 				f.file.onClosedCallback(true)
 			}
 			callback(storage.OpenFileFromURI(f.selected.location))
+		} else if f.file.isDirectory() {
+			callback := f.file.callback.(func(fyne.ListableURI, error))
+			f.win.Hide()
+			if f.file.onClosedCallback != nil {
+				f.file.onClosedCallback(true)
+			}
+			callback(f.dir, nil)
 		}
 	})
 	f.open.Style = widget.PrimaryButton
@@ -136,6 +143,8 @@ func (f *fileDialog) makeUI() fyne.CanvasObject {
 		if f.file.callback != nil {
 			if f.file.save {
 				f.file.callback.(func(fyne.URIWriteCloser, error))(nil, nil)
+			} else if f.file.isDirectory() {
+				f.file.callback.(func(fyne.ListableURI, error))(nil, nil)
 			} else {
 				f.file.callback.(func(fyne.URIReadCloser, error))(nil, nil)
 			}
@@ -157,7 +166,11 @@ func (f *fileDialog) makeUI() fyne.CanvasObject {
 	scrollBread := widget.NewHScrollContainer(f.breadcrumb)
 	body := fyne.NewContainerWithLayout(layout.NewBorderLayout(scrollBread, nil, nil, nil),
 		scrollBread, f.fileScroll)
-	header := widget.NewLabelWithStyle(label+" File", fyne.TextAlignLeading, fyne.TextStyle{Bold: true})
+	title := label + " File"
+	if f.file.isDirectory() {
+		title = label + " Folder"
+	}
+	header := widget.NewLabelWithStyle(title, fyne.TextAlignLeading, fyne.TextStyle{Bold: true})
 
 	favorites := f.loadFavorites()
 
@@ -215,6 +228,9 @@ func (f *fileDialog) refreshDir(dir fyne.ListableURI) {
 		if isHidden(file) {
 			continue
 		}
+		if f.file.isDirectory() && !isListable(file) {
+			continue
+		}
 
 		_, err := storage.ListerForURI(file)
 		if err == nil {
@@ -273,6 +289,10 @@ func (f *fileDialog) setLocation(dir fyne.ListableURI) error {
 		)
 	}
 
+	if f.file.isDirectory() {
+		f.fileName.SetText(dir.Name())
+		f.open.Enable()
+	}
 	f.refreshDir(dir)
 
 	return nil
@@ -479,6 +499,10 @@ func (f *FileDialog) SetOnClosed(closed func()) {
 
 // SetFilter sets a filter for limiting files that can be chosen in the file dialog.
 func (f *FileDialog) SetFilter(filter storage.FileFilter) {
+	if f.isDirectory() {
+		fyne.LogError("Cannot set a filter for a folder dialog", nil)
+		return
+	}
 	f.filter = filter
 	if f.dialog != nil {
 		f.dialog.refreshDir(f.dialog.dir)

dialog/file_mobile.go

@@ -23,7 +23,11 @@ func isHidden(file fyne.URI) bool {
 }
 
 func fileOpenOSOverride(f *FileDialog) bool {
-	gomobile.ShowFileOpenPicker(f.callback.(func(fyne.URIReadCloser, error)), f.filter)
+	if f.isDirectory() {
+		gomobile.ShowFolderOpenPicker(f.callback.(func(fyne.ListableURI, error)))
+	} else {
+		gomobile.ShowFileOpenPicker(f.callback.(func(fyne.URIReadCloser, error)), f.filter)
+	}
 	return true
 }
 

dialog/folder.go

@@ -0,0 +1,41 @@
+package dialog
+
+import (
+	"fyne.io/fyne"
+	"fyne.io/fyne/storage"
+)
+
+var folderFilter = storage.NewMimeTypeFileFilter([]string{"application/x-directory"})
+
+// NewFolderOpen creates a file dialog allowing the user to choose a folder to open.
+// The dialog will appear over the window specified when Show() is called.
+func NewFolderOpen(callback func(fyne.ListableURI, error), parent fyne.Window) *FileDialog {
+	dialog := &FileDialog{}
+	dialog.callback = callback
+	dialog.parent = parent
+	dialog.filter = folderFilter
+	return dialog
+}
+
+// ShowFolderOpen creates and shows a file dialog allowing the user to choose a folder to open.
+// The dialog will appear over the window specified.
+func ShowFolderOpen(callback func(fyne.ListableURI, error), parent fyne.Window) {
+	dialog := NewFolderOpen(callback, parent)
+	if fileOpenOSOverride(dialog) {
+		return
+	}
+	dialog.Show()
+}
+
+func (f *FileDialog) isDirectory() bool {
+	return f.filter == folderFilter
+}
+
+func isListable(u fyne.URI) bool {
+	if _, ok := u.(fyne.ListableURI); ok {
+		return true
+	}
+
+	_, err := storage.ListerForURI(u)
+	return err == nil
+}

go.mod

@@ -7,7 +7,7 @@ require (
 	github.com/akavel/rsrc v0.8.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/fsnotify/fsnotify v1.4.9
-	github.com/fyne-io/mobile v0.0.3-0.20201019162131-a1e87190904e
+	github.com/fyne-io/mobile v0.0.3-0.20201023100309-6e4995148130
 	github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7
 	github.com/go-gl/glfw/v3.3/glfw v0.0.0-20200625191551-73d3c3675aa3
 	github.com/godbus/dbus/v5 v5.0.3

go.sum

@@ -8,8 +8,8 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/fsnotify/fsnotify v1.4.9 h1:hsms1Qyu0jgnwNXIxa+/V/PDsU6CfLf6CNO8H7IWoS4=
 github.com/fsnotify/fsnotify v1.4.9/go.mod h1:znqG4EE+3YCdAaPaxE2ZRY/06pZUdp0tY4IgpuI1SZQ=
-github.com/fyne-io/mobile v0.0.3-0.20201019162131-a1e87190904e h1:8uXNy4NvCpLlfg1R01TJk0+n5trhDc0vofqbA/S1I48=
-github.com/fyne-io/mobile v0.0.3-0.20201019162131-a1e87190904e/go.mod h1:/kOrWrZB6sasLbEy2JIvr4arEzQTXBTZGb3Y96yWbHY=
+github.com/fyne-io/mobile v0.0.3-0.20201023100309-6e4995148130 h1:l+E5KcwiFEOR/0y8I+fIlUOpvSskhyNQ/8e2geqRJ6Y=
+github.com/fyne-io/mobile v0.0.3-0.20201023100309-6e4995148130/go.mod h1:/kOrWrZB6sasLbEy2JIvr4arEzQTXBTZGb3Y96yWbHY=
 github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7 h1:SCYMcCJ89LjRGwEa0tRluNRiMjZHalQZrVrvTbPh+qw=
 github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7/go.mod h1:482civXOzJJCPzJ4ZOX/pwvXBWSnzD4OKMdH4ClKGbk=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20200625191551-73d3c3675aa3 h1:q521PfSp5/z6/sD9FZZOWj4d1MLmfQW8PkRnI9M6PCE=

internal/driver/gomobile/file.go

@@ -74,3 +74,15 @@ func ShowFileOpenPicker(callback func(fyne.URIReadCloser, error), filter storage
 		}, mobileFilter(filter))
 	}
 }
+
+// ShowFolderOpenPicker loads the native folder open dialog and calls back the chosen directory path as a ListableURI.
+func ShowFolderOpenPicker(callback func(fyne.ListableURI, error)) {
+	filter := storage.NewMimeTypeFileFilter([]string{"application/x-directory"})
+	drv := fyne.CurrentApp().Driver().(*mobileDriver)
+	if a, ok := drv.app.(hasPicker); ok {
+		a.ShowFileOpenPicker(func(uri string, _ func()) {
+			f, err := drv.ListerForURI(storage.NewURI(uri))
+			callback(f, err)
+		}, mobileFilter(filter))
+	}
+}

vendor/modules.txt

@@ -8,7 +8,7 @@ github.com/akavel/rsrc/ico
 github.com/davecgh/go-spew/spew
 # github.com/fsnotify/fsnotify v1.4.9
 github.com/fsnotify/fsnotify
-# github.com/fyne-io/mobile v0.0.3-0.20201019162131-a1e87190904e
+# github.com/fyne-io/mobile v0.0.3-0.20201023100309-6e4995148130
 github.com/fyne-io/mobile/app
 github.com/fyne-io/mobile/app/internal/callfn
 github.com/fyne-io/mobile/event/key