Add Icon to the left of the title in the action bar in android

Question

I want to add a clickable icon/button to the left of the title in the action bar . How to do it? Following is the code with which I have added search and setting icon to the act

Answer 1

You can replace default navigation icon (and button of cause) in following way.

Define usual UI with toolbar in your XML:

Then setup your Toolbar as ActionBar in onCreate method

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_menu);

    Toolbar toolbar = findViewById(R.id.toolbar);

    setSupportActionBar(toolbar);
    getSupportActionBar().setDisplayHomeAsUpEnabled(true); // Make toolbar show navigation button (i.e back button with arrow icon)

    toolbar.setNavigationIcon(R.drawable.custom_icon); // Replace arrow icon with our custom icon
}

Handle back navigation button in onOptionsItemSelected method:

@Override
    public boolean onOptionsItemSelected(MenuItem menuItem) {
        if (menuItem.getItemId() == android.R.id.home) {

            // Do whatever you want

            return true;
        }

        return super.onOptionsItemSelected(menuItem);
    }

The same in Kotlin

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        setSupportActionBar(toolbar)

        supportActionBar?.setDisplayHomeAsUpEnabled(true) // Important step, we enable button on the left side of the toolbar

        toolbar.navigationIcon = getDrawable(R.drawable.custom_icon) // Here we change default navigation button icon

    }

    override fun onOptionsItemSelected(item: MenuItem): Boolean {
        return when (item.itemId) {
            android.R.id.home -> {
                doSomething() // Here we can perform any action
                true
            }
            else -> super.onOptionsItemSelected(item)
        }
    }

    private fun doSomething() {
        Toast.makeText(this, "Hello", Toast.LENGTH_LONG).show()
    }
}

Result: