AboutActivity.java

package com.dxjia.doubantop.activitys;

import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;

import com.dxjia.doubantop.R;

import butterknife.ButterKnife;
import butterknife.InjectView;

public class AboutActivity extends AppCompatActivity {

    @InjectView(R.id.toolbar)
    Toolbar mToolbar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_about);
        ButterKnife.inject(this);

        setSupportActionBar(mToolbar);

        final ActionBar actionBar = getSupportActionBar();
        if (actionBar != null) {
            actionBar.setDisplayHomeAsUpEnabled(true);
        }
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        switch (id) {
            case android.R.id.home:
                this.finish();
                return true;
        }

        return super.onOptionsItemSelected(item);
    }

}