我尝试按照Android教程测试Android O中的Notification Channel。当我进入显示通知的步骤时,我看到他们使用TaskStackBuilder
,我想知道addParentStack()
在做什么?
因为当我删除这行代码时它仍然可以正常工作。
我尝试通过添加更多这样的父级来测试它:
private PendingIntent getPendingIntent() {
Intent openMainIntent = new Intent(this, MainActivity.class);
Intent openMain2Intent = new Intent(this, Main2Activity.class);
Intent openMain3Intent = new Intent(this, Main3Activity.class);
// The stack builder object will contain an artificial back stack for the
// started Activity.
// This ensures that navigating backward from the Activity leads out of
// your application to the Home screen.
TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);
// Adds the back stack for the Intent (but not the Intent itself)
stackBuilder.addParentStack(MainActivity.class);
stackBuilder.addParentStack(Main2Activity.class);
// Adds the Intent that starts the Activity to the top of the stack
stackBuilder.addNextIntent(openMain3Intent);
return stackBuilder.getPendingIntent(0, PendingIntent.FLAG_ONE_SHOT);
}
如上面的代码,我添加了多个父级,并期望当我从Main3Activity
按回来时,它应分别转到Main2Activity
和MainActivity
,但结果是它返回到主页屏幕立即。
我通过移除addParentStack()
并添加了更多addNextIntent()
来更改它:
private PendingIntent getPendingIntent() {
Intent openMainIntent = new Intent(this, MainActivity.class);
Intent openMain2Intent = new Intent(this, Main2Activity.class);
Intent openMain3Intent = new Intent(this, Main3Activity.class);
// The stack builder object will contain an artificial back stack for the
// started Activity.
// This ensures that navigating backward from the Activity leads out of
// your application to the Home screen.
TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);
// Adds the Intent that starts the Activity to the top of the stack
stackBuilder.addNextIntent(openMainIntent);
stackBuilder.addNextIntent(openMain2Intent);
stackBuilder.addNextIntent(openMain3Intent);
return stackBuilder.getPendingIntent(0, PendingIntent.FLAG_ONE_SHOT);
}
按照我的预期,一切正常,当我按下按钮时,它打开Main3Activity
并转到Main2Activity
和MainActivity
。
我发现有些人说当我使用android:parentActivityName
时,我需要在AndroidManifest.xml
中添加addParentStack()
,我做了但结果是一样的,没有任何反应。
所以,如果有人能告诉我,我将不胜感激:
addParentStack()
做什么? addParentStack()
和addNextIntent()
之间的区别是什么?addParentStack()
吗?提前感谢。
答案 0 :(得分:1)
所以,我在官方文件中找到了这个
<强> 1.addParentStack()强>
它会添加后退堆栈(意味着如果您按下后退按钮,它将带您进入此方法的活动)
2. addParentStack()和addNextIntent()之间的距离
基本区别是addnextIntent()会将意图添加到堆栈顶部
3.我们需要addParentStack()吗?
如果您不想在按下后退按钮后转到父活动,或者您已在清单文件中声明
以下代码来自官方文档,它将帮助您理解
int id = 1;
...
Intent resultIntent = new Intent(this, ResultActivity.class);
TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);
// Adds the back stack
stackBuilder.addParentStack(ResultActivity.class);
// Adds the Intent to the top of the stack
stackBuilder.addNextIntent(resultIntent);
// Gets a PendingIntent containing the entire back stack
PendingIntent resultPendingIntent =
stackBuilder.getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT);
...
NotificationCompat.Builder builder = new NotificationCompat.Builder(this);
builder.setContentIntent(resultPendingIntent);
NotificationManager mNotificationManager =
(NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
mNotificationManager.notify(id, builder.build());