can't detect windows arise distance altered c++ mfc

February 15, 2012

i'm perplexing establish i detect user changes windows arise distance normal additional infinite fonts, arise distance comparison executing following stairs windows xp machine:

right-click desktop name properties.

click coming tab.

select arise size: normal/large fonts/extra infinite fonts

my bargain arise distance change law dpi change, here i've attempted far.

my goal:

i wish detect windows arise size altered normal infinite additional infinite fonts take actions formed arise distance change. i assume windows arise distance changes, dpi also change (especially distance additional infinite fonts

what i've attempted far:

i accept several messages including: wm_settingchange, wm_nccalcsize, wm_ncpaint, etc... nonetheless zero messages unparalleled conditions arise distance changes, words, i accept wm_settingschange summary i wish know changed.

in speculation i interpretation onsettingchange windows calls it, lpszsection should tell me changing domain is, works fine, nonetheless following i check given domain job systemparametersinfo i pass movement spi_getnonclientmetrics, i step by debugger i certain i watch information returned nonclientmetrics any arise changes, nonetheless zero occur.

even didn't work, i should still means check dpi settings change. i unequivocally wouldn't caring details, each i wm_settingchange message, i only check dpi perform actions i'm prying performing, nonetheless i'm means component dpi either.

i have attempted dpi invoking slight getsystemmetrics, also any dc:

dekstop dc->getdevicecaps logpixelsx/logpixelsy
window dc->getdevicecaps logpixelsx/logpixelsy
current dc->getdevicecaps logpixelsx/logpixelsy

even i change dpi distinguished properties window values don't relapse anything different, always arrangement 96.

could anybody assistance me figure out please? should i looking for? where should i looking at?

afx_msg vacant cmainframe::onsettingchange(uint uflags, lpctstr lpszsection)
{
    int windowdpi = 0;
    int devicedpi = 0;
    int systemdpi = 0;
    int desktopdpi = 0;
    int dpi_00_x = 0;
    int dpi_01_x = 0;
    int dpi_02_x = 0;
    int dpi_03_x = 0;

    cdc* windowdc = cwnd::getwindowdc(); // try window dc
    hdc desktop = ::getdc(null); // try desktop dc
    cdc* device = cwnd::getdc(); // try tide dc
    hdc hdc = *device; // try hdc
    if( windowdc )
    {
        windowdpi = windowdc->getdevicecaps(logpixelsy); 
        // always 96 regardless i change arise 
        // distance additional infinite fonts keep during normal

        dpi_00_x = windowdc->getdevicecaps(logpixelsx); // 96
    }

    if( desktop )
    {
        desktopdpi = ::getdevicecaps(desktop, logpixelsy); // 96
        dpi_01_x = ::getdevicecaps(desktop, logpixelsx); // 96
    }

    if( device )
    {
        devicedpi = device->getdevicecaps(logpixelsy); // 96
        dpi_02_x = device->getdevicecaps(logpixelsx); // 96
    }

    systemdpi = ::getdevicecaps(hdc, logpixelsy); // 96
    dpi_03_x = ::getdevicecaps(hdc, logpixelsx); // 96

    cwnd::releasedc(device);
    cwnd::releasedc(windowdc);
    ::releasedc(null, desktop);
    ::releasedc(null, hdc);

    cwnd::onwinsettingchange(uflags, lpszsection);
}

the dpi always advantage 96, nonetheless settings changes take outcome i change arise distance additional infinite fonts i change dpi 120 (from graphics properties).

code1