一、Splash界面的作用
用来展现产品的logo
应用程序初始化的操作
检查应用程序的版本
检查当前应用程序是否合法注册
二、界面的xml定义
写一个布局背景设置为产品的logo图片，再添加一个textview显示版本号。
<TextView android:id="@+id/tv_splash_version" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textColor="#000000" android:textStyle="bold" android:shadowDx="1"//阴影的偏移量 android:shadowDy="1" android:shadowRadius="0.2"//阴影的半径 android:shadowColor="#ffff00" android:text="版本：1.0" android:textSize="16sp" android:layout_centerInParent="true"/>
public String getAppVersion(){
PackageManager pm = getPackageManager();
try {
PackageInfo info = pm.getPackageInfo(getPackageName(),0);
return info.versionName;
} catch (NameNotFoundException e) {
e.printStackTrace();
//不可能发生；
return "";
}
}
protected void showUpdateDialog() {
AlertDialog.Builder build = new Builder(this);
build.setTitle("发现新版本");
build.setMessage(description);
build.setNegativeButton("立刻升级",new OnClickListener() {
@Override
public void onClick(DialogInterface dialog,int which) {
//升级的代码；
};
});
build.setPositiveButton("下次再说",int which) {
dialog.dismiss();
enterHome();
}
});
build.show();
private void checkup() {
new Thread() {
public void run() {
Message msg = Message.obtain();
long startTime = System.currentTimeMillis();//启动该线程的系统时间
try {
//请求网络的代码
URL url = new URL(getString(R.string.serverurl));
HttpURLConnection conn = (HttpURLConnection) url
.openConnection();
conn.setRequestMethod("GET");//请求方法
conn.setConnectTimeout(4000);//超时时间
int code = conn.getResponseCode();//返回码200请求成功
if (code == 200) {
InputStream is = conn.getInputStream();
String result = StreamTools.readFromStream(is);
Log.i(TAG,"联网成功" + result);
JSONObject obj = new JSONObject(result);//解析json字符串
String version = (String) obj.get("version");//版本信息
description = (String) obj.get("description");//描述信息
apkurl = (String) obj.get("apkurl");
if (getAppVersion().equals(version)) {
msg.what = ENTER_HOME;
} else {
msg.what = SHOW_UPDATE_DIALOG;
}
}
} catch (MalformedURLException e) {
e.printStackTrace();
msg.what = URL_ERROR;
} catch (IOException e) {
e.printStackTrace();
msg.what = NETWORK_ERROR;
} catch (JSONException e) {
e.printStackTrace();
msg.what = JSON_ERROR;
} finally {
handler.sendMessage(msg);
long endTime = System.currentTimeMillis();//该线程执行完毕的时间
long dTime = endTime-startTime;//该线程的阻塞时间
if (dTime<3000) {
try {
Thread.sleep(3000-dTime);//若该线程的阻塞时间小于三秒继续睡眠到三秒
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
}.start();
}
handler
private Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
// TODO Auto-generated method stub
super.handleMessage(msg);
switch (msg.what) {
case SHOW_UPDATE_DIALOG:
showUpdateDialog();
break;
case ENTER_HOME:
Toast.makeText(getApplicationContext(),"",0).show();
enterhome();
break;
case URL_ERROR:
Toast.makeText(getApplicationContext(),"URL_ERROR",0).show();
enterhome();
break;
case NETWORK_ERROR:
Toast.makeText(getApplicationContext(),"NETWORK_ERROR",0).show();
enterhome();
break;
case JSON_ERROR:
Toast.makeText(getApplicationContext(),"JSON_ERROR",0).show();
enterhome();
break;
}
}
};
五、下载文件（使用Afinal框架）并调用系统安装工具安装APK
if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
FinalHttp finalHttp = new FinalHttp();
finalHttp.download(apkurl,Environment.getExternalStorageDirectory().getAbsolutePath()+
"/mobilesafe2.0.apk",new AjaxCallBack<File>() {
@Override
public void onLoading(long count,long current) {
super.onLoading(count,current);
tv_uapdate_info.setVisibility(View.VISIBLE);
int progress =(int) (current*100/count);
tv_uapdate_info.setText("下载进度："+progress+"%");
}
@Override
public void onFailure(Throwable t,int errorNo,String strMsg) {
t.printStackTrace();
Toast.makeText(getApplicationContext(),"下载失败",0).show();
enterhome();
super.onFailure(t,errorNo,strMsg);
}
@Override
public void onSuccess(File t) {
super.onSuccess(t);
installAPK(t);
}
private void installAPK(File t) {
Intent intent = new Intent();//自动安装程序可调用该段代码
intent.setAction("android.intent.action.VIEW");
intent.addCategory("android.intent.category.DEFAULT");
intent.setDataAndType(Uri.fromFile(t),"application/vnd.android.package-archive");
startActivity(intent);
}
});
}else{
Toast.makeText(getApplicationContext(),"请插入内存卡再试",0).show();
return;
}
其他：
1、显示4.0的样式：方式是去掉功能清单里的Activity对应的android:theme；
放到application里面；
2、当splash页面弹出升级提示框过滤点击返回的是两种方式：
builder.setCancelable(false);
设置setOnCancelListener 当触屏的时候直接进入主页面
对话框是挂载在Activity上面的,如果Activity不存在，对话框就不能被创建。
getApplicationContext();生命周期长，只要应用还存活它就存在；this 生命周期短，只要Activity不存在了，系统就会回收
其中：getBaseContext(),getApplication(),getApplicationContext(); 都不能放在AlertDialog做上下文；
3.Splash用来宣传和隐藏程序启动细节是很有用的。
用Handler的实现方法如下：（也可以用线程实现，不推荐）
定义一个Activity，用来显示你的图片，其中最重要的就是定义一个Handler，用来发送和接收消息：
public class WelcomeActivity extends Activity
{
//定义一个handler,用来接收延迟发送的信息-启动activity
private Handler handler = new Handler()
{
@Override
<span style="color: #ff0000;">public void handleMessage(Message msg) </span>
{
// TODO Auto-generated method stub
super.handleMessage(msg);
switch(msg.what)
{
case 0x123:
Intent intent = new Intent(WelcomeActivity.this,OnlineExamActivity.class);
startActivity(intent);
finish();
}
}
};
在onCreate()方法中，用handler发送消息，延迟3000毫秒：
@Override
protected void onCreate(Bundle savedInstanceState)
{
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.welcome_activity);
start();
}
private void start()
{
<span style="color: #ff0000;">handler.sendEmptyMessageDelayed(0x123,3000);</span>
}
