Android 判断网络状态是否断开,不多说了,看代码吧!
/**
* 判断网络状态是否可用
* @return true: 网络可用 ; false: 网络不可用
*/
public boolean isConnectInternet() {
ConnectivityManager conManager=(ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE );
NetworkInfo networkInfo = conManager.getActiveNetworkInfo();
if (networkInfo != null ){ // 注意,这个判断一定要的哦,要不然会出错
return networkInfo.isAvailable();
}
return false ;
}
最后别忘要在加上
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
这个权限哦!
下面我介绍一下对于多个 Activity 的应用程序的完全关闭方法:
在 ActivityManager 类中提供了如下的方法:
/**
* Have the system perform a force stop of everything associated with
* the given application package. All processes that share its uid
* will be killed, all services it has running stopped, all activities
* removed, etc. In addition, a {@link Intent#ACTION_PACKAGE_RESTARTED}
* broadcast will be sent, so that any of its registered alarms can * be stopped, notifications removed, etc.
*
* You must hold the permission * {@link android.Manifest.permission#RESTART_PACKAGES} to be able to
* call this method.
*
* @param packageName The name of the package to be stopped.
*/
public void restartPackage(String packageName) {
try {
ActivityManagerNative.getDefault().restartPackage(packageName);
}
catch (RemoteException e) { }
}
所以如果要关闭整个应用程序的话只需要运行以下两行代码就行:
ActivityManager activityMgr= (ActivityManager) this.getSystemService(ACTIVITY_SERVICE );
activityMgr.restartPackage(getPackageName());
最后还需要添加这个权限才行:
<!-- 关闭应用程序的权限 -->
<uses-permission android:name="android.permission.RESTART_PACKAGES" />
描述 :
本文讲述了 Android 中不同 Activity 之间的数据传递 — Bundle 对象的实现。
例子 :
有兴趣的朋友可以在登录后下载本文例子代码!
例子效果图 :
实现步骤 :
第一步 :建 立 Android 工程: BundleDemo 。
第二步 :编写 Activity 的子类别: BundleDemo ,其程序代码如下:
package com.a3gs.bundle;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.RadioGroup;
public class BundleDemo extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button btn = (Button) findViewById(R.id.btn);
btn.setOnClickListener(new Button.OnClickListener(){
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
EditText et = (EditText) findViewById(R.id.height);
double height = Double.parseDouble(et.getText().toString());
String sex = "";
RadioGroup rg = (RadioGroup) findViewById(R.id.sex);
if(rg.getCheckedRadioButtonId() == R.id.M) {
sex = "M";
}
if(rg.getCheckedRadioButtonId() == R.id.F) {
sex = "F";
}
// 用 Bundle 来绑定所要的数据
Bundle bd = new Bundle();
bd.putDouble("height", height);
bd.putString("sex", sex);
// 创建一个新的 Intent ,并将 Bundle 传进去
Intent it = new Intent();
it.putExtras(bd);
it.setClass(BundleDemo.this, Bundle2.class);
startActivity(it);
BundleDemo.this.finish();
}
});
}
}接下