在版本迭代時下載新版本的時候有些APP展示帶進度條的通知欄,對使用者而言感覺更為友好,以下是在Activity裡的簡單實現.

截圖如下:

程式碼如下:

import android.app.Notification;
import android.app.NotificationManager;
import android.os.Bundle;
import android.os.SystemClock;
import android.support.v4.app.NotificationCompat;
import android.support.v7.app.AppCompatActivity;
import 
 
android.widget.RemoteViews;

import java.util.Locale;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.TimeUnit;

public class MainActivity extends AppCompatActivity {

    private NotificationCompat.Builder builder
 
;
    private NotificationManager manager;

    private ScheduledFuture<?> future;

    private int count;//模似進度
@Override
protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        manager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE
 
);

        ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor();
        future = executor.scheduleAtFixedRate(new MyThread(), 0, 100, TimeUnit.MILLISECONDS);
    }

    private Notification customNotification(int progress, String text) {//自定義View通知
if (builder == null)
            builder = new NotificationCompat.Builder(this);

        RemoteViews view = new RemoteViews(getPackageName(), R.layout.notification_upgrade);
        view.setProgressBar(R.id.bar, 100, progress, false);
        view.setTextViewText(R.id.tv_des, text);
        view.setTextViewText(R.id.tv_progress, String.format(Locale.getDefault(), "%d%%", progress));

        builder.setCustomContentView(view)
                .setSmallIcon(R.mipmap.ic_launcher)
                .setAutoCancel(true);
        return builder.build();
    }

    //這裡為了方便閱讀就放在Activity裡,實際情況放在Service裡更好
private class MyThread implements Runnable {
        @Override
public void run() {
            manager.notify("Download", 0, customNotification(++count, "下載中"));
            if (count == 100) {
                manager.notify("Download", 0, customNotification(count, "下載完成了"));
                SystemClock.sleep(3000);

                manager.cancel("Download", 0);
                if (future != null)
                    future.cancel(false);
            }
        }
    }

    @Override
protected void onDestroy() {
        super.onDestroy();
        if (future != null)
            future.cancel(true);
    }
}

自定義通知的佈局檔案notification_upgrade.xml如下:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:orientation="horizontal"
android:paddingBottom="5dp"
android:paddingLeft="10dp"
android:paddingRight="10dp"
android:paddingTop="5dp">

    <ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:contentDescription="@string/app_name"
android:scaleType="centerInside"
android:src="@mipmap/ic_launcher" />

    <LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:layout_marginStart="10dp"
android:orientation="vertical">

        <LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">

            <TextView
android:id="@+id/tv_des"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="@color/black"
android:textStyle="bold" />

            <TextView
android:id="@+id/tv_progress"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:layout_marginStart="10dp"
android:textColor="@color/black"
android:textStyle="bold" />
        </LinearLayout>

        <ProgressBar
android:id="@+id/bar"
style="@style/Widget.AppCompat.ProgressBar.Horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
    </LinearLayout>
</LinearLayout>