背景知識:當Android啓動時,會發出一個系統廣播,內容爲ACTION_BOOT_COMPLETED,它的字
符串常量表示爲 android.intent.action.BOOT_COMPLETED。只要在程序中「捕捉」到這個消息,再啓動之
便可。記住,Android框架說:Don''t call me, I''ll call you back。咱們要作的是作好接收這個消息的準備,而
實現的手段就是實現一個BroadcastReceiver。html
一、界面Activity,BootStartDemo.java文件java
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public
class
BootStartDemo
extends
Activity {
/** Called when the activity is first created. */
@Override
public
void
onCreate(Bundle savedInstanceState) {
super
.onCreate(savedInstanceState);
// 無title
requestWindowFeature(Window.FEATURE_NO_TITLE);
// 全屏
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.main);
new
Thread() {
public
void
run() {
try
{
/* 10秒後關閉頁面*/
sleep(
10000
);
}
catch
(Exception e) {
e.printStackTrace();
}
finally
{
finish();
// 關閉頁面
}
}
}.start();
}
}
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這段代碼很簡單,當Activity 啓動時,會顯示TextView,用它顯示你想顯示的字樣,而且這個頁面只顯示10秒後消失。android
二、接收廣播消息:BootBroadcastReceiver.javaapp
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public
class
BootBroadcastReceiver
extends
BroadcastReceiver {
static
final
String action_boot=
"android.intent.action.BOOT_COMPLETED"
;
@Override
public
void
onReceive(Context context, Intent intent) {
if
(intent.getAction().equals(action_boot)){
Intent ootStartIntent=
new
Intent(context,BootStartDemo.
class
);
//通過測試這個必定設置,啓動Activity的幾種方式之一,具體的本身搜索下
ootStartIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(ootStartIntent);
}
}
}
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該類繼續自 BroadcastReceiver,覆載方法 onReceive 中,檢測接收到的 Intent 是否符合
BOOT_COMPLETED,若是符合,則啓動BootStartDemo這個Activity。框架
三、配置文件ide
(1)AndroidManifest.xml :測試
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<?xml version=
"1.0"
encoding=
"utf-8"
?>
<!-- 這是一個開機自啓動程序 -->
<manifest xmlns:android=
"http://schemas.android.com/apk/res/android"
package
=
"com.ajie.bootstartdemo"
android:versionCode=
"1"
android:versionName=
"1.0"
>
<application android:icon=
"@drawable/icon"
android:label=
"@string/app_name"
>
<activity android:name=
".BootStartDemo"
android:label=
"@string/app_name"
>
<intent-filter>
<action android:name=
"android.intent.action.MAIN"
/>
<category android:name=
"android.intent.category.LAUNCHER"
/>
</intent-filter>
</activity>
<span style=
"color: #ff00ff;"
><receiver android:name=
".BootBroadcastReceiver"
>
<intent-filter>
<action android:name=
"android.intent.action.BOOT_COMPLETED"
/>
<category android:name=
"android.intent.category.HOME"
/>
</intent-filter>
</receiver>
</span> </application>
<span style=
"color: #ff00ff;"
><strong><uses-permission android:name=
"android.permission.RECEIVE_BOOT_COMPLETED"
></uses-permission></strong>
</span></manifest>
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注意其中顏色標紅那一部分,該節點向系統註冊了一個 receiver,子節點 intent-filter 表示接收
android.intent.action.BOOT_COMPLETED 消息。而且還要配置android.permission.RECEIVE_BOOT_COMPLETED權限。spa
(2)Layout文件,main.xmlcode
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<?xml version=
"1.0"
encoding=
"utf-8"
?>
<LinearLayout xmlns:android=
"http://schemas.android.com/apk/res/android"
android:orientation=
"vertical"
android:layout_width=
"fill_parent"
android:layout_height=
"fill_parent"
>
<TextView
android:layout_width=
"fill_parent"
android:layout_height=
"fill_parent"
android:text=
"@string/boottext"
android:textColor=
"#5F2DD2"
android:background=
"#FFFFFF"
android:textSize=
"60px"
android:gravity=
"center_horizontal"
/>
</LinearLayout>
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完成後,編譯出apk包,安裝到模擬器或手機中。關機,從新開機,就會顯示BootStartDemo這個Activity顯示出來的頁面。orm