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VistasWhy "screen.height" works fine when using Chrome' DevTool to simulate mobile devices, but not on real mobile devices?
The screen.height I am talking about is described in https://www.w3schools.com/jsref/prop_screen_height.asp
I used screen.height < 560 ? true : false to determine whether the screen height is smaller than a threshold, so I can hide some UI elements in this case.
It works fine in Chrome's simulator for mobile devices (the feature highlighted below).
By "works fine", I mean when simulating a mobile device, like setting device to be iPhone X as shown above and displaying in landscape mode, the UI elements are hidden correctly due to screen.height < 560 = true.
However, on real mobile devices like a real iPhone X, the UI elements don't get hidden, which I guess is because that it is always screen.height < 560 = false, even if it is in landscape mode.
I am wondering why is that... Why iPhone X in DevTool has a different height from a real iPhone X?
Is the simulation in Chrome DevTool not accurate? Or is it because screen.height doesn't return the correct value on mobile device?
Any hints would be appreciated!
2 Respuestas
Responde la pregunta0
It might be because you are missing the response meta tag. Try adding this to your head tag:
<meta name="viewport" content="width=device-width, initial-scale=1">
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That's because the simulator takes the screen size according to the dimensions that you are setting there. But in reality, screen.height takes the height size of the whole screen, including elements that are outside of the viewport in the device. You should use window.innerHeight to get an accurate height size.
If you log in your console screen.height and window.innerHeight on the simulator, you will get the same size. If you do this in the normal viewport (deactivating the simulator), you will get different values.
More info: Screen Height - Window InnerHeight
UPDATE
screen.height doesn't update on screen rotation, always has the same value corresponding to the screen height in portrait mode, while window.innerHeight takes the current height of the device window either portrait or landscape. Just make sure to fire this in the event when the rotation happens.
For this, you could use the Window.matchMedia() like so:
// Breakpoints
const breakpoint = window.matchMedia('(max-height: 560px)');
// Breakpoint checker
const breakpointMutations = () => {
if (breakpoint.matches === true) {
// Do something
}
}
// Run breakpoint checker if media changes
breakpoint.onchange = function (event) {
breakpointMutations();
}
// Run breakpoint checker on load
breakpointMutations();