Merge pull request #11873 from electron/add-file-format-picker

add accessory view for format picker

atom/browser/ui/file_dialog_mac.mm

@@ -14,10 +14,42 @@
 #include "base/mac/scoped_cftyperef.h"
 #include "base/strings/sys_string_conversions.h"
 
+@interface PopUpButtonHandler : NSObject
+@property (nonatomic, strong) NSSavePanel *savePanel;
+@property (nonatomic, strong) NSArray *fileTypes;
+- (instancetype)initWithPanel:(NSSavePanel *)panel andTypes:(NSArray *)types;
+- (void)selectFormat:(id)sender;
+@end
+
+@implementation PopUpButtonHandler
+- (instancetype)initWithPanel:(NSSavePanel *)panel andTypes:(NSArray *)types {
+  self = [super init];
+  if (self) {
+    _savePanel = panel;
+    _fileTypes = types;
+  }
+  return self;
+}
+
+- (void)selectFormat:(id)sender {
+  NSPopUpButton *button = (NSPopUpButton *)sender;
+  NSInteger selectedItemIndex = [button indexOfSelectedItem];
+  NSString *nameFieldString = [[self savePanel] nameFieldStringValue];
+  NSString *trimmedNameFieldString = [nameFieldString stringByDeletingPathExtension];
+  NSString *extension = [[self fileTypes] objectAtIndex: selectedItemIndex];
+
+  NSString *nameFieldStringWithExt = [NSString stringWithFormat:@"%@.%@", trimmedNameFieldString, extension];
+  [[self savePanel] setNameFieldStringValue:nameFieldStringWithExt];
+  [[self savePanel] setAllowedFileTypes:@[extension]];
+}
+@end
+
 namespace file_dialog {
 
 namespace {
 
+static PopUpButtonHandler *popUpButtonHandler;
+
 void SetAllowedFileTypes(NSSavePanel* dialog, const Filters& filters) {
   NSMutableSet* file_type_set = [NSMutableSet set];
   for (size_t i = 0; i < filters.size(); ++i) {
@@ -25,6 +57,7 @@ void SetAllowedFileTypes(NSSavePanel* dialog, const Filters& filters) {
     for (size_t j = 0; j < filter.second.size(); ++j) {
       // If we meet a '*' file extension, we allow all the file types and no
       // need to set the specified file types.
+
       if (filter.second[j] == "*") {
         [dialog setAllowsOtherFileTypes:YES];
         return;
@@ -41,6 +74,29 @@ void SetAllowedFileTypes(NSSavePanel* dialog, const Filters& filters) {
     file_types = [file_type_set allObjects];
 
   [dialog setAllowedFileTypes:file_types];
+
+  if (!popUpButtonHandler)
+    popUpButtonHandler = [[PopUpButtonHandler alloc] initWithPanel:dialog andTypes:file_types];
+
+  // add file format picker
+  NSView  *accessoryView = [[NSView alloc] initWithFrame:NSMakeRect(0.0, 0.0, 200, 32.0)];
+  NSTextField *label = [[NSTextField alloc] initWithFrame:NSMakeRect(0, 0, 60, 22)];
+
+  [label setEditable:NO];
+  [label setStringValue:@"Format:"];
+  [label setBordered:NO];
+  [label setBezeled:NO];
+  [label setDrawsBackground:NO];
+
+  NSPopUpButton *popupButton = [[NSPopUpButton alloc] initWithFrame:NSMakeRect(50.0, 2, 140, 22.0) pullsDown:NO];
+  [popupButton addItemsWithTitles:file_types];
+  [popupButton setTarget:popUpButtonHandler];
+  [popupButton setAction:@selector(selectFormat:)];
+
+  [accessoryView addSubview:label];
+  [accessoryView addSubview:popupButton];
+
+  [dialog setAccessoryView:accessoryView];
 }
 
 void SetupDialog(NSSavePanel* dialog,