Android杂谈--网络状态判断
许多联网应用都在开始运行的时候检查当前网络状态，如果没有开启则去开启它，记录一下以前写程序时的网络检查，发现人的记忆力真是有限，总是隔段时间久忘记，所以记录下来是最好的记忆。
我们可以在一开始启动程序的时候检查网络连接状况，如果没有开启则弹出对话框设置网络
首先需要加入权限
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>
<uses-permission android:name="android.permission.INTERNET"/>
检查网络状态代码如下
public boolean CheckNetworkState()
{
boolean flag = false;
ConnectivityManager manager = (ConnectivityManager)getSystemService(
Context.CONNECTIVITY_SERVICE);
if(manager.getActiveNetworkInfo() != null)
{
flag = manager.getActiveNetworkInfo().isAvailable();
}
if(!flag)
{
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setIcon(android.R.drawable.ic_dialog_alert);
builder.setTitle(R.string.netstate);
builder.setMessage(R.string.setnetwork);
builder.setPositiveButton(R.string.ok, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
Intent mIntent = new Intent("/");
ComponentName comp = new ComponentName("com.android.settings",
"com.android.settings.WirelessSettings");
mIntent.setComponent(comp);
mIntent.setAction("android.intent.action.VIEW");
startActivity(mIntent);
}
});
builder.setNegativeButton(R.string.cancel, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
builder.create();
builder.show();
}
return flag;
}
如果希望网络连接时做一些事情的话，需要判断当前网络状态是否为true，为真则进行一些操作，否则设置网络。还可以用另外一种方式，其实差不多
//setnetwork
public void setNetwork()
{
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setIcon(android.R.drawable.ic_dialog_alert);
builder.setTitle(R.string.netstate);
builder.setMessage(R.string.setnetwork);
builder.setPositiveButton(R.string.ok, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
Intent mIntent = new Intent("/");
ComponentName comp = new ComponentName("com.android.settings",
"com.android.settings.WirelessSettings");
mIntent.setComponent(comp);
mIntent.setAction("android.intent.action.VIEW");
startActivity(mIntent);
}
});
builder.setNegativeButton(R.string.cancel, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
builder.create();
builder.show();
}
//NETWORK
public boolean isNetworkAvailable()
{
Context context = getApplicationContext();
ConnectivityManager connect = (ConnectivityManager)context.getSystemService(
Context.CONNECTIVITY_SERVICE);
if(connect==null)
{
return false;
}else//get all network info
{
NetworkInfo[] info = connect.getAllNetworkInfo();
if(info!=null)
{
for(int i=0;i<info.length;i++)
{
if(info[i].getState()==NetworkInfo.State.CONNECTED)
{
return true;
}
}
}
}
return false;
}
