java - Android 用户界面 : activity_main. xml 和 content_main.xml

Question

我是 Android 开发新手。目前我正在尝试弄清楚 Android 用户界面是如何创建的。

我记得以前，用户界面和布局是在 activity_main.xml 文件中设计的。

我创建了一个新 Activity ，它为我生成了两个用户界面文件:activity_main.xml 和 content_main.xml。 content_main.xml 似乎包含布局和用户界面元素。在这种情况下，什么activity_main.xml。我必须使用它吗？

MainActivity.java

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG).setAction("Action", null).show();
            }
        });
    }
}

Answer 1

you should use it . you use include layout to keep clean and understandable your xml..most of the time your xml is to big which is very difficult to find any view(Button,Image etc) ..rather than including entire view into one xml we seprate them and include them ....when you setContentView your layout only one view hierarchy is created..