Android和Java：无法对我的App主题和App图标进行任何修改

Question

as I'm very new to Android programming, this may be a simple question, but I was googling for an answer for hours now and all results did not work for me.

I'm using Android studio and I'd like to have an application Icon on the top left corner in my action bar.

I created a new project with a blank activity using Android V. 4.1 (API 16) as minSDK and API 21 as targetSDK.

When I compile & run the new project on my mobile device (Android V 4.3, Samsung G S3), I get the blank activity with an action bar that contains the activity title.

The tutorials on android's website always show an action bar that displays the app icon on the left side of the activity title, but it isn't displayed on my screen..

I googled for it and found solutions to "enable" the home icon in my MainActivity class (extends ActionBarActivity):

getActionBar().setIcon(R.id.launcher);
getActionBar().setLogo(R.id.launcher);
getActionBar().setDisplayShowHomeEnabled(true);

Every of these three tries resulted in an error on my mobile device "application stopped"..

Then, I read that newer themes don't display the icon anymore. Is that correct? Well, I don't know if it is correct, but I even can't change my theme. Right now, by default, the app uses the Theme.AppCompat.Light.DarkActionBar . My problem is, that I can't change it to some other theme like Theme.Holo or Theme.Material , I always get errors on my mobile device or Android Studio simply doesn't accept the theme.

Well, does anybody know what I'm doing wrong? I also tried to inherit my MainActivity from Activity instead of ActionBarActivity , but the result was always the same...

Answer 1

Officially the support for showing App Icon or Logo in the ActionBar has been removed as per The Material Design Guidelines

You can't use Icon or any Logo especially if your using AppCompat library

Answer 2

You should reference drawables in your application by R.drawable . R.id is normally used for the id of a View. Try to replace setIcon(R.id.launcher) with setIcon(R.drawable.launcher) .