Develop Reference

NavigationDrawer - Different toolbar for each fragment

I have an app with a single Activity(MainActivity) and a Navigation Drawer. The navigation drawer, of course, opens the fragments in the activity. The problem I am facing is that I have already linked the MainActivity toolbar to the ActionToggle (hamburger) when I created an object of the ActionToggle. So the MainActivity toolbar shows in all fragments, but I want different toolbar XML for each fragments. If I want to hide the MainActivity toolbar in the fragments, the ActionToggle (hamburger) will also get hidden.
Please, how can I have different toolbar for each fragment, with the MainActivity ActionToggle in all the toolbars?

I would have expected the question to be clearer, but as I understand it, I can help you in the following way.
-If you want to change your toolbar from within different fragments,
below code block can help you.
Toolbar toolbar = view.findViewById(R.id.toolbar);
((MainActivity) getActivity()).getSupportActionBar().hide();
((MainActivity) getActivity()).setSupportActionBar(toolbar);
-If you just want to change the toolbar properties such as the title, you can use the code block below.
Toolbar toolbar = (Toolbar) getActivity().findViewById(R.id.toolbar);
toolbar.setTitle("title");

Show navigation icon without implementing navigationDrawer

I am using a custom navigation drawer (or something similar) which doesn't extend the default NavigationDrawer. Therefore it doesn't automatically show the navigation button on the top left of the ActionBar. I would like to implement that functionality that normally comes with the NavigationDrawer.
I have tried many things, such as :
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
toolbar.setNavigationIcon(R.drawable.ic_menu_black_24dp);
setSupportActionBar(toolbar);
or:
getSupportActionBar().setHomeButtonEnabled(true);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setHomeAsUpIndicator(R.drawable.ic_menu_black_24dp);
or:
getSupportActionBar().setIcon(R.drawable.ic_menu_black_24dp);
but I just can't seem to get it to work. Any suggestions?

Put the code into your styles.xml file:
<item name="homeAsUpIndicator">#drawable/ic_drawer</item>
<item name="android:homeAsUpIndicator">#drawable/ic_drawer</item>

you have to set ActionBarDrawerToggle like below to set home icon.
mToggle.setHomeAsUpIndicator(R.mipmap.ico_menu);
mToggle is Object of your ActionBarDrawerToggle.

I fixed this problem by implementing a custom toolbar layout and using it as the supportActionBar.

Android Toolbar set title explanation

I have my app Toolbar here:
toolbar = (Toolbar) findViewById(R.id.app_bar);
setSupportActionBar(toolbar);
When i want to set the screen title, i have to do the following:
ActionBar bar = getSupportActionBar();
if (bar != null) {
bar.setTitle(SCREEN_TITLE);
}
My questions is, why when calling the toolbar.setTitle() is not working. But instead i need to get the action bar first and then i can set the title?
P.S. In the other hand, I can set the Toolbar icon normally without getting the action bar as so:
toolbar.setNavigationIcon(R.drawable.ic_arrow_back_white);

A Toolbar is a generalization of action bars for use within application layouts.
Unlike Action bar , toolbar is not part of window decor.You defines it and place it just like any other widget...therefor you have freedom to place it anywhere in the parent layout.
You have freedom to put any widget inside toolbar.
You can define multiple toolbars.
Toolbar may be placed at any arbitrary level of nesting within a view hierarchy. An application may choose to designate a Toolbar as the action bar for an Activity using the setActionBar() method.
As Toolbar is generalization of ActionBar. you have to first set Toolbar as ActionBar then you can use all method of ActionBar.
EDIT:
Here is Link that explains Toolbar concept.
Here is bug link reported in android issues: In issue they suggest that Once you call setSupportActionBar(Toolbar), the Action Bar is then responsible for handling the title, meaning that you need to call getSupportActionBar().setTitle(...) to set a custom title. It also gives explanation about why toolbar.setNavigationIcon(R.drawable.ic_arrow_back_white); works.
I hope it helps!

Material Design Menu Item

So here I thought after implementing Material Design everything would be just like it says in the guideline. But when I used a menu item with only a title (THE RIGHT ONE, NOT HOME ICON), it's not the same as what it would like in the guideline :
Instead, it's still like this :
Or do I have to create a custom view to have a menu item like that? if so, how?
Thank you for your help..

You can try calling getSupportActionBar().setIcon(R.drawable.your_icon); in the onCreate method of your activity
Or if you are using toolbar, you can do the following:
Toolbar toolbar = (Toolbar) findViewById(R.id.my_toolbar);
setSupportActionBar(toolbar);
toolbar.setNavigationIcon(R.drawable.your_icon);
toolbar.setTitle("");

Toolbar vs appcompat v7-21 toolbar

What is the difference between the two? what all features are included in toolbar thats not in v7-21 toolbar? What all limitations are there in using v7-21 tollbar in place of toolbar?

If you look at the documentation for the Toolbar and the AppCompat Toolbar you can see that functionally, there aren't any differences between the two. Of course the SDK level required differs between the two and to use the Toolbar you have to call setActionBar(mToolbar); but with the support Toolbar you have to call setSupportActionBar(mToolbar);