Mac Preferences Read and Write

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Revision as of 13:29, 21 October 2019 by Trev (talk | contribs) (IValid -> IsValid and explained significance; reformatted code)
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macOSlogo.png

This article applies to macOS only.

See also: Multiplatform Programming Guide

For those who want to read and write preferences for a macOS application, this can be done using the following methods:

CODE FOR READING PREFERENCES
  uses MacOSAll, CFPreferences;

  var
    IsValid: Boolean;  // On return indicates if key exists and has valid data
    Pref: Integer;

  procedure TForm1.FormCreate(Sender: TObject);
  begin
    try
       Pref := CFPreferencesGetAppIntegerValue(CFStr('Check1'),kCFPreferencesCurrentApplication,IsValid);
       if (Pref = 1) then
          CheckBox1.Checked := true
       else
          CheckBox1.Checked := false;

       Pref := CFPreferencesGetAppIntegerValue(CFStr('Check2'),kCFPreferencesCurrentApplication,IsValid);
       if (Pref = 1) then
          CheckBox2.Checked := true
       else
          CheckBox2.Checked := false;

       Pref := CFPreferencesGetAppIntegerValue(CFStr('Check3'),kCFPreferencesCurrentApplication,IsValid);
       if (Pref = 1) then
          CheckBox3.Checked := true
       else
          CheckBox3.Checked := false;

       Pref := CFPreferencesGetAppIntegerValue(CFStr('Check4'),kCFPreferencesCurrentApplication,IsValid);
       if (Pref = 1) then
          CheckBox4.Checked := true
       else
          CheckBox4.Checked := false;

    except
      on E : Exception do
        ShowMessage(E.ClassName+' error raised, with message : '+E.Message);
    end;
  end;


CODE FOR WRITING PREFERENCES
  uses MacOSAll, CFPreferences;

  var
    ItemName: CFStringRef;
    ItemVal: CFPropertyListRef;

  procedure TForm1.FormClose(Sender: TObject);
  begin
    try
       if (CheckBox1.Checked) then
         begin
           ItemName := CFStr('Check1');
           ItemVal := CFStringCreateWithPascalString(kCFAllocatorDefault,'1',kCFStringEncodingUTF8);
           CFPreferencesSetAppValue(ItemName,ItemVal,kCFPreferencesCurrentApplication);
         end
       else
         begin
           ItemName := CFStr('Check1');
           ItemVal := CFStringCreateWithPascalString(kCFAllocatorDefault,'0',kCFStringEncodingUTF8);
           CFPreferencesSetAppValue(ItemName,ItemVal,kCFPreferencesCurrentApplication);
         end;

       if (CheckBox2.Checked) then
         begin
           ItemName := CFStr('Check2');
           ItemVal := CFStringCreateWithPascalString(kCFAllocatorDefault,'1',kCFStringEncodingUTF8);
           CFPreferencesSetAppValue(ItemName,ItemVal,kCFPreferencesCurrentApplication);
         end
       else 
         begin
           ItemName := CFStr('Check2');
           ItemVal := CFStringCreateWithPascalString(kCFAllocatorDefault,'0',kCFStringEncodingUTF8);
           CFPreferencesSetAppValue(ItemName,ItemVal,kCFPreferencesCurrentApplication);
         end;
       
       if (CheckBox3.Checked) then
         begin
           ItemName := CFStr('Check3');
           ItemVal := CFStringCreateWithPascalString(kCFAllocatorDefault,'1',kCFStringEncodingUTF8);
           CFPreferencesSetAppValue(ItemName,ItemVal,kCFPreferencesCurrentApplication);
         end
       else
         begin
           ItemName := CFStr('Check3');
           ItemVal := CFStringCreateWithPascalString(kCFAllocatorDefault,'0',kCFStringEncodingUTF8);
           CFPreferencesSetAppValue(ItemName,ItemVal,kCFPreferencesCurrentApplication);
         end;

       if (CheckBox4.Checked) then
         begin
           ItemName := CFStr('Check4');
           ItemVal := CFStringCreateWithPascalString(kCFAllocatorDefault,'1',kCFStringEncodingUTF8);
           CFPreferencesSetAppValue(ItemName,ItemVal,kCFPreferencesCurrentApplication);
         end
       else
         begin
           ItemName := CFStr('Check4');
           ItemVal := CFStringCreateWithPascalString(kCFAllocatorDefault,'0',kCFStringEncodingUTF8);
           CFPreferencesSetAppValue(ItemName,ItemVal,kCFPreferencesCurrentApplication);
         end;

       CFPreferencesAppSynchronize(kCFPreferencesCurrentApplication);

     except
       on E : Exception do
         ShowMessage(E.ClassName+' error raised, with message : '+E.Message);
     end;

Prefs1.png


See also