Question

我刚刚开始学习Android，我的Java知识有限，但是半天能用c / c ++目标C等...我目前正在编写一本名为Beginning Android Application Development的p2pwrox电子书，但是我来了在第73页的“试一试：在状态栏上显示通知”中取消。

我已经设法把它写得很好，我已经习惯了android sdk和eclipse ide，但是我在下面显示的NotificationActivity.java文件中遇到了这个错误，我只是不知道如何解决。< / p>

    package com.androidtestingfun.www;

import android.app.Activity;
import android.os.Bundle;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.view.View;
import android.widget.Button;

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

        Button button = (Button) findViewById(R.id.btn_displaynotif);
        button.setOnClickListener(new Button.OnClickListener() {
            public void onClick(View v) {
                displayNotification();
            }
        });
    }

    protected void displayNotification()
    {
        //---PendingIntent to launch activity if the user selects this notification---
        Intent i = new Intent(this, NotificationView.class);
        i.putExtra("notificationID", notificationID); //-----the second parameter here is getting an error

        PendingIntent pendingIntent = 
                PendingIntent.getActivity(this, 0, i, 0);

        NotificationManager nm = (NotificationManager)
                getSystemService(NOTIFICATION_SERVICE);

        Notification notif = new Notification(
                R.drawable.icon,
                "Reminder: Meeting starts in 5 minutes",
                System.currentTimeMillis());

        CharSequence from = "System Alarm";
        CharSequence message = "Meeting with customer at 3pm...";

        notif.setLatestEventInfo(this, from, message, pendingIntent);

        //---100ms delay, vibrate for 250ms, pause for 100ms and then vibrate for 500ms---
        notif.vibrate = new long[] {100, 250, 100, 500};
        nm.notify(notificationID, notif);//-----the first parameter here is getting an error
    }
}

任何可以听到我的想法都会非常感激，我已经尝试过清理我的版本，但是没有做任何事情来帮助。

Answer 1

您没有名为notificationID的变量。

将此变量添加到类中，请参阅代码段示例：

public class NotificationsActivity extends Activity {

    private static final int notificationID = 1234;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        // ........
    }

    protected void displayNotification()
    {
        //---PendingIntent to launch activity if the user selects this notification---
        Intent i = new Intent(this, NotificationView.class);
        i.putExtra("notificationID", notificationID); 

        PendingIntent pendingIntent = 
                PendingIntent.getActivity(this, 0, i, 0);

        NotificationManager nm = (NotificationManager)
                getSystemService(NOTIFICATION_SERVICE);

        Notification notif = new Notification(
                R.drawable.icon,
                "Reminder: Meeting starts in 5 minutes",
                System.currentTimeMillis());

        CharSequence from = "System Alarm";
        CharSequence message = "Meeting with customer at 3pm...";

        notif.setLatestEventInfo(this, from, message, pendingIntent);

        notif.vibrate = new long[] {100, 250, 100, 500};
        nm.notify(notificationID, notif);
    }
}

notificationID无法解析为变量

1 个答案: