android---菜单栏选项

android菜单栏选项

layout.xml

main.java

package com.example.optionmenu;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Switch;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {
TextView txt;
MenuItem item;

    @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    txt = findViewById(R.id.TextView);
}
public boolean onCreateOptionsMenu(Menu menu)
    {
        super.onCreateOptionsMenu(menu);
        menu.add(
                1,//组号
                1,//ID
                1,//排序
                "菜单栏1");
        menu.add(1,2,2,"菜单栏2");
        menu.add(1,3,3,"菜单栏3");
        menu.add(1,4,4,"菜单栏4");
        return true;

    }
    @Override
    public boolean onOptionsItemSelected(MenuItem Item)
    {
        String title = "选择了"+item.getTitle().toString();
        switch (item.getItemId())
        {
            case 1:
                txt.setText(title);
                break;
            case 2:
                txt.setText(title);
                break;
            case 3:
                txt.setText(title);
                break;
            case 4:
                txt.setText(title);
                break;
            default:
                return super.onOptionsItemSelected(item);
        }
        return true;
    }

}