Android 上的导航返回按钮不起作用

Question

I have wrote this code to enable the navigation back button. Its appearing on run time but after clicking on it is not doing anything. Can someone tell me please what I'm missing?

// Get a support ActionBar corresponding to this toolbar
ActionBar ab = getSupportActionBar();

// Enable the Up button
ab.setDisplayHomeAsUpEnabled(true);

Thank you!

Answer 1

You should override onOptionsItemSelected method in your activity.

    override fun onOptionsItemSelected(item: MenuItem): Boolean {
    return when (item.itemId) {
        android.R.id.home -> {
            finish()
            true
        }
        else -> super.onOptionsItemSelected(item)
    }
}

Also if i'm not mistaken you should add this to your action bar to:

supportActionBar?.setDisplayShowHomeEnabled(true)