On Thu, 15 May 2025 18:13:35 GMT, Andy Goryachev <ango...@openjdk.org> wrote:
>> Some platform preference changes can trigger the emission of multiple >> notifications. For example, when switching from a high-contrast theme on >> Windows to the regular theme, the following notifications are emitted (log >> can be viewed in `PlatformPreferencesChangedTest`): >> >> >> changed: >> Windows.UIColor.Accent=0x0078d4ff >> Windows.SysColor.COLOR_HIGHLIGHTTEXT=0xffffffff >> Windows.SysColor.COLOR_WINDOW=0xffffffff >> Windows.UIColor.AccentLight1=0x0091f8ff >> Windows.SysColor.COLOR_3DFACE=0xf0f0f0ff >> Windows.SysColor.COLOR_HOTLIGHT=0x0066ccff >> Windows.SysColor.COLOR_WINDOWTEXT=0x000000ff >> Windows.SysColor.COLOR_BTNTEXT=0x000000ff >> Windows.UIColor.Foreground=0x000000ff >> Windows.UIColor.AccentDark1=0x0067c0ff >> Windows.UIColor.Background=0xffffffff >> Windows.UIColor.AccentLight3=0x99ebffff >> Windows.UIColor.AccentLight2=0x4cc2ffff >> Windows.SysColor.COLOR_GRAYTEXT=0x6d6d6dff >> Windows.SysColor.COLOR_HIGHLIGHT=0x0078d7ff >> Windows.UIColor.AccentDark2=0x003e92ff >> Windows.UIColor.AccentDark3=0x001a68ff >> >> changed: >> -Windows.SPI.HighContrastColorScheme >> Windows.SPI.HighContrast=false >> >> changed: >> Windows.UIColor.Foreground=0xffffffff >> Windows.UIColor.Background=0x000000ff >> >> >> Notably, the values for Windows.UIColor.Foreground/Background are >> inconsistent between the notifications (although they are eventually >> correct). In general, only a single notification should be emitted that >> includes all of the changed preferences. >> >> This artifact is only visible on Windows. The reason is that changing some >> system settings (like high-contrast theme) causes a number of different >> window messages to be sent to the application. We should wait for all window >> messages to come in, and then aggregate all of the changed preferences into >> a single notification. >> >> In order to minimize the delay between changing a system setting and sending >> out the notification in JavaFX, the implementation only waits when >> instructed to do so by the native toolkit. This allows us to instantly send >> out notifications for most changes, but selectively wait a bit for changes >> where the native toolkit knows that more changes might be coming in. > > modules/javafx.graphics/src/main/native-glass/win/PlatformSupport.h line 75: > >> 73: * Suggested aggregation delay for changes that come in over a >> period of time. >> 74: */ >> 75: static constexpr int SUGGESTED_DELAY_MILLIS = 1000; > > 1 second seems too long. > What is the typical range for the high contrast train of changes? Quite a lot, Windows takes around 1-2 seconds to change to and from a high-contrast theme (there's even a full-frame wait screen that pops up). The suggested delay of 1 second works reliably on my machine. ------------- PR Review Comment: https://git.openjdk.org/jfx/pull/1810#discussion_r2091755001