Add Up-Navigation Properties in Custom ActionBar Button in Android

Question

I want to create my own ActionBar Layout.

Like this (created in Paint for example)

Is it possible to give the second Button the Up-Navigation Properties? So if I press it, it finish this Activity and starts it's parent.

I want to have the burger Icon for the Navigation Drawer, the Up-Icon for Up-Navigation and the Title of the Activity.

Is it possible? Or is there a solution already?

Answer 1

Actually, it's fairly easy(though it's little hacky) to do. First, create a drawable for back button(preferably - as a selector, to distinguish pressed/normal state:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="true" android:drawable="@drawable/back_button_pressed"/>
    <item android:drawable="@drawable/back_button"/>
</selector>

Next, set this drawable to the logo of the toolbar toolbar.setLogo(R.drawable.back_button_selector);

Then the only thing left is to set click-listener.

View logoView = getToolbarLogoIcon(toolbar);
logoView.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        onBackPressed();
    }
});

...

private View getToolbarLogoIcon(Toolbar toolbar){
    //check if contentDescription previously was set
    boolean hadContentDescription = android.text.TextUtils.isEmpty(toolbar.getLogoDescription());
    String contentDescription = String.valueOf(!hadContentDescription ? toolbar.getLogoDescription() : "logoContentDescription");
    toolbar.setLogoDescription(contentDescription);
    ArrayList<View> potentialViews = new ArrayList<>();

    //find the view based on it's content description, set programatically or with android:contentDescription
    toolbar.findViewsWithText(potentialViews,contentDescription, View.FIND_VIEWS_WITH_CONTENT_DESCRIPTION);

    //Nav icon is always instantiated at this point because calling setLogoDescription ensures its existence
    View logoIcon = null;
    if (potentialViews.size() > 0) {
        logoIcon = potentialViews.get(0);
    }

    //Clear content description if not previously present
    if (hadContentDescription) {
        toolbar.setLogoDescription(null);
    }

    return logoIcon;
}

(Thanks Nicola's post here). Or if you are not scared of reflection, it can be easily done like this:

    try {
        Field declaredField = toolbar.getClass().getDeclaredField("mLogoView");
        declaredField.setAccessible(true);
        View logoView = (View) declaredField.get(toolbar);
        logoView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onBackPressed();
            }
        });
    } catch (Exception ex) {
        //error
    }

Another possible solution would be to set custom layout to the ActionBar. Though, I'm advocating to follow the UI/UX guidelines and double-check, if navigation drawer is essential in the secondary activity.