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HI All,

In Compose Multiplatform Web (JS), when I load the content in my Android Web browser i want to override the hardware back button of Android device how to do it?

Same answer on the same question
<https://kotlinlang.slack.com/archives/C01F2HV7868/p1742152767119479?thread_ts=1742150178.914479&amp;channel=C01F2HV7868&amp;message_ts=1742152767.119479|https://kotlinlang.slack.com/archives/C01F2HV7868/p1742152767119479?thread_ts=1742150178.914479&amp;channel=C01F2HV7868&amp;message_ts=1742152767.119479>

FYI cross posting to multiple channels is considered spamming.

<@U01HMQ42G1Y>


import kotlinx.browser.window

fun main() {
    // Add an initial state
    window.history.pushState(null, "", window.location.href)

    // Listen for back navigation
    window.onpopstate = { event -&gt;
        println("Back button pressed!")
        // Custom logic here, e.g., navigate within the app
        // Optionally push another state to "trap" the back button
        window.history.pushState(null, "", window.location.href)
    }
}

I used the above code to achieve what i requested, the answer you gave was not satisfactory for me so I thought better to ping in <#C0B8L3U69|> channel, but because you commented with saying that is not possible I think no one answered my question. Please respond to the questions if  you are 100 percent sure what you said is correct or else please let others answer .

This only happens if the back button is navigating your webpage. The brower app does not necessarily do that on each back button press. So what you have is a hack that might function but does not need to work all the time.

You asked for „override the hardware back button“ and that’s definitely not possible from JavaScript.

You’re right that the History API approach relies on the back button triggering navigation within the webpage, and it’s not a guaranteed catch for every scenario—sometimes the browser might just close the tab or app instead. I’d call it more of a workaround than a full override of the hardware back button, since JavaScript can’t directly hook into that. That said, it actually worked for my use case! I tested it on my Android device, and after some user interaction, the popstate event fired consistently when I hit the back button. It’s not perfect, but it got the job done for me.