1.多个Activity共用相同布局或者相同控件：避免重复代码

BaseActivit代码：

public class BaseActivity extends Activity implements OnClickListener{    /*     * 多个Activity共用相同布局或者相同控件     * 写个基类继承，避免重复代码     */    @Override    public void onClick(View v)    {        switch (v.getId())        {        case R.id.common_titlebar_btn_back:            finish();            break;        default:            break;        }        baseOnClick(v);    }                     protected void baseOnClick(View v)    {                         }                     @Override    protected void onCreate(Bundle savedInstanceState)    {        super.onCreate(savedInstanceState);//        setContentView(R.layout.activity_base);    }                     @Override    protected void onResume()    {        super.onResume();        onPostOnCreate();    }                     public final void onPostOnCreate()//find同一个控件    {        findViewById(R.id.common_titlebar_btn_back).setOnClickListener(this);    }    @Override    public boolean onCreateOptionsMenu(Menu menu)    {        getMenuInflater().inflate(R.menu.base, menu);        return true;    }}

子类代码：

public class ThirdActivity extends BaseActivity{    /**     *  layout里复用同一布局：     *     
          */    @Override    protected void onCreate(Bundle savedInstanceState)    {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_third_main);    }}