最近设计安卓里面有个标题栏，里面有个后退键，可以完成后退之类的功能。

好，刚好可以用Toolbar去实现

上代码：activity_main.xml

这里需要引用styles.xml在里面加样式

最后主程序：

package action.sun.com.testtoobar1;import android.os.Bundle;import android.support.design.widget.FloatingActionButton;import android.support.design.widget.Snackbar;import android.support.v7.app.AppCompatActivity;import android.support.v7.widget.Toolbar;import android.view.View;import android.view.Menu;import android.view.MenuItem;import android.view.Window;import android.view.WindowManager;import android.widget.Toast;public class MainActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        /*getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,                WindowManager.LayoutParams.FLAG_FULLSCREEN);    //设置全屏*/        setContentView(R.layout.activity_main);        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);        //一定要加，为了去掉本身的标题文字        toolbar.setTitle("");        //初始化toolbar        setSupportActionBar(toolbar);        //左边的小箭头（注意需要在setSupportActionBar(toolbar)之后才有效果）        toolbar.setNavigationIcon(R.mipmap.back);    }    @Override    public boolean onCreateOptionsMenu(Menu menu) {        // Inflate the menu; this adds items to the action bar if it is present.        Toast.makeText(MainActivity.this, "选择了菜单", Toast.LENGTH_SHORT).show();        //初始化右边的菜单选项        //getMenuInflater().inflate(R.menu.menu_main, menu);        return 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();        Toast.makeText(MainActivity.this, "选择了后退按钮="+id, Toast.LENGTH_SHORT).show();        //noinspection SimplifiableIfStatement        return super.onOptionsItemSelected(item);    }}

到此代码完毕，就能够完成需要上图实现的效果了