运行效果:
1.menu/main.xml
showAsAction属性:
never :在下方弹出显示
always:在右上方显示
2.Activity中
package zz.itcast.menu;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
// 这个方法就是创建一个菜单 只要复写了这个方法 说明你想弹出菜单 就写返回true
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
// 将菜单的布局转成菜单 R.drawble
getMenuInflater().inflate(R.menu.main, menu);
// 返回true代表菜单要显示
return true;
}
// 当菜单条目被选中时
@Override
public boolean onMenuItemSelected(int featureId, MenuItem item) {
// TODO Auto-generated method stub
switch (item.getItemId()) {
case R.id.setting:
Toast.makeText(this, "设置", 0).show();
break;
case R.id.connection_us:
Toast.makeText(this, "联系我们", 0).show();
break;
case R.id.about:
Toast.makeText(this, "关于", 0).show();
break;
case R.id.exit:
finish();
break;
default:
break;
}
return super.onMenuItemSelected(featureId, item);
}
}
用用场景:
系统应用中使用较多