android - 从其他 Activity 调用菜单

Question

请指导我如何调用其他 Activity 的菜单

这里是主要 Activity

package com.droidnova.android.howto.optionmenu;



import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.widget.Toast;

public class ControlMenu extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.menu, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.settings:     
                Intent intent = new Intent(this, ShowSettings.class);
                  startActivity(intent);
            break;
            case R.id.services:     Toast.makeText(this, "You pressed the text!", Toast.LENGTH_LONG).show();
                                break;
            case R.id.Quit: 

                new Thread(new Runnable() {
                    public void run() {                         
                        ControlMenu.this.finish();

                        // The following makes the Android Gods frown upon me
                        android.os.Process.killProcess(android.os.Process.myPid());
                        System.exit(0);
                    }
                }).start();
                break;
            default:    
            break;
        }
        return true;
    }
}

现在我进行了另一项 Activity ，我需要在此 Activity 中显示相同的菜单

package com.droidnova.android.howto.optionmenu;

import android.app.Activity;
import android.app.AlertDialog;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class ShowSettings extends Activity {

    Prefs myprefs = null;

    final String tag = "CH12:ShowSettings";

    AlertDialog.Builder adb;// = new AlertDialog.Builder(this);

    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);

        setContentView(R.layout.showsettings);

        this.myprefs = new Prefs(getApplicationContext());

        // load screen
        PopulateScreen();

        this.adb = new AlertDialog.Builder(this);

        final Button savebutton = (Button) findViewById(R.id.settingssave);

        // create anonymous click listener to handle the "save"
        savebutton.setOnClickListener(new Button.OnClickListener() {

            public void onClick(View v) {
                try {

                    // get the string and do something with it.

                    final EditText email = (EditText) findViewById(R.id.emailaddress);
                    if (email.getText().length() == 0) {

                        AlertDialog ad = ShowSettings.this.adb.create();
                        ad.setMessage("Please Enter Your Email Address");
                        ad.show();
                        return;
                    }

                    final EditText serverurl = (EditText) findViewById(R.id.serverurl);
                    if (serverurl.getText().length() == 0) {
                        AlertDialog ad = ShowSettings.this.adb.create();
                        ad.setMessage("Please Enter The Server URL");
                        ad.show();
                        return;
                    }

                    // save off values
                    ShowSettings.this.myprefs.setEmail(email.getText().toString());
                    ShowSettings.this.myprefs.setServer(serverurl.getText().toString());
                    ShowSettings.this.myprefs.save();

                    // we're done!
                    finish();
                } catch (Exception e) {
                    Log.i(ShowSettings.this.tag, "Failed to Save Settings [" + e.getMessage() + "]");
                }
            }
        });
    }

    private void PopulateScreen() {
        try {
            final EditText emailfield = (EditText) findViewById(R.id.emailaddress);
            final EditText serverurlfield = (EditText) findViewById(R.id.serverurl);

            emailfield.setText(this.myprefs.getEmail());
            serverurlfield.setText(this.myprefs.getServer());
        } catch (Exception e) {

        }
    }
}

我应该在上面的代码中写些什么，这样我的菜单也可以出现在这里。

Answer 1

将菜单创建为 xml 资源，然后您就可以从任何地方访问它。检查documentation .如果您只需要将某些数据从一个 Activity 传递到另一个 Activity ，那么扩展 Application 似乎太多了，因为您可以在 Intent 中将信息作为 en extra 传递。此外，这种做事方式存在“危险”(由于 activity lyfecicle)，因此在这种情况下您应该使用 SharedPreferences(而不是创建 Application 全局变量)。