8 files changed, 55 insertions(+), 0 deletions(-)

M explorer/explorer.go
M explorer/explorer_android.go
M explorer/explorer_ios.go
M explorer/explorer_js.go
M explorer/explorer_linux.go
M explorer/explorer_macos.go
M explorer/explorer_unsupported.go
M explorer/explorer_windows.go

@@ 114,6 114,33 @@ func (e *Explorer) ChooseFile(extensions ...string) (io.ReadCloser, error) {
 	return e.importFile(extensions...)
 }
 
+// ChooseFiles shows the files selector, allowing the user to select multiple files.
+// Optionally, it's possible to define which file extensions is supported to
+// be selected (such as `.jpg`, `.png`).
+//
+// Example: ChooseFiles(".jpg", ".png") will only accept the selection of files with
+// .jpg or .png extensions.
+//
+// In some platforms the resulting `io.ReadCloser` is a `os.File`, but it's not
+// a guarantee.
+//
+// In most known browsers, when user clicks cancel then this function never returns.
+//
+// It's a blocking call, you should call it on a separated goroutine. For most OSes, only one
+// ChooseFile{,s} or CreateFile, can happen at the same time, for each app.Window/Explorer.
+func (e *Explorer) ChooseFiles(extensions ...string) ([]io.ReadCloser, error) {
+	if e == nil {
+		return nil, ErrNotAvailable
+	}
+
+	if runtime.GOOS != "js" {
+		e.mutex.Lock()
+		defer e.mutex.Unlock()
+	}
+
+	return e.importFiles(extensions...)
+}
+
 // CreateFile opens the file selector, and writes the given content into
 // some file, which the use can choose the location.
 //

@@ 132,6 132,10 @@ func (e *Explorer) importFile(extensions ...string) (io.ReadCloser, error) {
 	return file.file.(io.ReadCloser), nil
 }
 
+func (e *Explorer) importFiles(_ ...string) ([]io.ReadCloser, error) {
+	return nil, ErrNotAvailable
+}
+
 //export Java_org_gioui_x_explorer_explorer_1android_ImportCallback
 func Java_org_gioui_x_explorer_explorer_1android_ImportCallback(env *C.JNIEnv, _ C.jclass, stream C.jobject, id C.jint, err C.jstring) {
 	fileCallback(env, stream, id, err)

@@ 97,6 97,10 @@ func (e *Explorer) importFile(extensions ...string) (io.ReadCloser, error) {
 	return file.file.(io.ReadCloser), nil
 }
 
+func (e *Explorer) importFiles(_ ...string) ([]io.ReadCloser, error) {
+	return nil, ErrNotAvailable
+}
+
 //export importCallback
 func importCallback(u C.CFTypeRef, id C.int32_t) {
 	fileCallback(u, id)

@@ 50,6 50,10 @@ func (e *Explorer) importFile(extensions ...string) (io.ReadCloser, error) {
 	return file.file.(io.ReadCloser), nil
 }
 
+func (e *Explorer) importFiles(_ ...string) ([]io.ReadCloser, error) {
+	return nil, ErrNotAvailable
+}
+
 type FileReader struct {
 	buffer                   js.Value
 	isClosed                 bool

@@ 276,3 276,7 @@ func (e *Explorer) importFile(extensions ...string) (io.ReadCloser, error) {
 	}
 	return os.Open(filepath)
 }
+
+func (e *Explorer) importFiles(_ ...string) ([]io.ReadCloser, error) {
+	return nil, ErrNotAvailable
+}

@@ 69,6 69,10 @@ func (e *Explorer) importFile(extensions ...string) (io.ReadCloser, error) {
 	return resp.file.(io.ReadCloser), resp.error
 }
 
+func (e *Explorer) importFiles(_ ...string) ([]io.ReadCloser, error) {
+	return nil, ErrNotAvailable
+}
+
 //export importCallback
 func importCallback(u *C.char, id int32) {
 	if v, ok := active.Load(id); ok {

@@ 27,3 27,7 @@ func (e *Explorer) exportFile(_ string) (io.WriteCloser, error) {
 func (e *Explorer) importFile(_ ...string) (io.ReadCloser, error) {
 	return nil, ErrNotAvailable
 }
+
+func (e *Explorer) importFiles(_ ...string) ([]io.ReadCloser, error) {
+	return nil, ErrNotAvailable
+}

@@ 118,6 118,10 @@ func (e *Explorer) importFile(extensions ...string) (io.ReadCloser, error) {
 	return os.Open(path)
 }
 
+func (e *Explorer) importFiles(_ ...string) ([]io.ReadCloser, error) {
+	return nil, ErrNotAvailable
+}
+
 func buildFilter(extensions []string) *uint16 {
 	if len(extensions) <= 0 {
 		return nil