我为我的Android应用程序构建了对话框。它工作正常，但是我遇到了一些与对话框有关的问题。
（1）我想要在连接互联网或WiFi时。自动对话框消失。
（2）如果互联网连接丢失，则应用程序中间正在运行。对话框再次自动出现。
if (!isConnected(Dashboard.this)) buildDialog(Dashboard.this).show();
else {
setContentView(R.layout.activity_dashboard);
}
public boolean isConnected(Context context) {
ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netinfo = cm.getActiveNetworkInfo();
if (netinfo != null && netinfo.isConnectedOrConnecting()) {
android.net.NetworkInfo wifi = cm.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
android.net.NetworkInfo mobile = cm.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
if ((mobile != null && mobile.isConnectedOrConnecting()) || (wifi != null && wifi.isConnectedOrConnecting()))
return true;
else return false;
} else
return false;
}
public AlertDialog.Builder buildDialog(Context c) {
AlertDialog.Builder builder = new AlertDialog.Builder(c);
builder.setTitle("No Internet Connection");
builder.setMessage("You need to have Mobile Data or WiFi to access this. Press OK to Exit");
builder.setCancelable(false);
builder.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Dashboard.super.onBackPressed();
}
});
return builder;
}
答案 0 :(得分：1)
在aleart中使用属性builder.setCancelable(false);
答案 1 :(得分：1)
将此行放在警报对话框代码中
alertDialog.setCancelable(false);
答案 2 :(得分：1)
要自动获取Internet连接事件，请尝试设置网络更改监听器。这是一个示例：
/**
* Broadcast receiver that detects receives notification when change in internet connection to alert when there is no Internet.
*/
public class NetworkChangeReceiver extends BroadcastReceiver {
private NetworkChangeListener mListener;
public NetworkChangeReceiver(NetworkChangeListener listener) {
mListener = listener;
}
@Override
public void onReceive(final Context context, @NonNull final Intent intent) {
if (ConnectivityManager.CONNECTIVITY_ACTION.equals(intent.getAction())) {
ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetwork = connectivityManager.getActiveNetworkInfo();
boolean connected = activeNetwork != null && activeNetwork.isConnected();
mListener.onNetworkConnectedStateChanged(connected);
}
}
public interface NetworkChangeListener {
void onNetworkConnectedStateChanged(boolean connected);
}
}
然后您在“活动”或“片段”中注册侦听器
@Override
public void onStart() {
super.onStart();
if (mNetworkChangeReceiver == null) {
mNetworkChangeReceiver = new NetworkChangeReceiver(this);
getContext().registerReceiver(mNetworkChangeReceiver, new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION));
}
}
然后在网络连接状态更改时显示/关闭对话框
@Override
public void onNetworkConnectedStateChanged(boolean connected) {
if (connected) {
//dismiss dialog
} else {
//show dialog
}
}
答案 3 :(得分：0)
您必须将setCancelable == false设置为停止在对话框外滚动。
在您的情况下，必须在setMessage
之后将其放在 AlertDialog.Builder 中builder.setCancelable（false）;
并将此功能用于“后按”按钮上的用户，您必须设置Cancelable == true
为此，您必须像这样在onBackPressed中编写代码：-
builder.setCancelable（true）;
答案 4 :(得分：0)
您需要添加广播接收器以获取连接状态。
然后您需要使构建器保持全球化。
private AlertDialog.Builder builder;
答案 5 :(得分：0)
只需创建一个 BroadcastReceiver 来跟踪您的互联网连接
首先，创建一个像这样的 NetworkChangeReceiver 类
public class NetworkChangeReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
try {
if (isOnline(context)) {
//show dialog when internet on
dialogHome(true);
Log.e("pradeep", "Online Connect Internet ");
} else {
//hide dialog when internet off
dialogHome(false);
Log.e("pradeep", "Connectivity Failure !!");
}
} catch (NullPointerException e) {
e.printStackTrace();
Log.i(getClass().getName(), "exceptional " + e.toString());
}
}
public boolean isOnline(Context context) {
try {
ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = cm.getActiveNetworkInfo();
//should check null because in airplane mode it will be null
return (netInfo != null && netInfo.isConnected());
} catch (NullPointerException e) {
e.printStackTrace();
return false;
}
}
}
之后，只需在 AndroidMenifest.xml
中的 application 标签中添加以下代码 <receiver android:name=".utils.NetworkChangeReceiver">
<intent-filter>
<action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
</intent-filter>
</receiver>
最后一步
只需在您检查互联网活动的活动中创建您的BroadcastReceiver实例
private BroadcastReceiver mNetworkReceiver;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
//init broadcast receiver
mNetworkReceiver = new NetworkChangeReceiver();
}
@Override
protected void onResume() {
super.onResume();
if (((NetworkChangeReceiver) mNetworkReceiver).isOnline(mContext)) {
} else {
registerNetworkBroadcastForNougat();
}
}
private void registerNetworkBroadcastForNougat() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
try {
registerReceiver(mNetworkReceiver, new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION));
} catch (Exception e) {
Log.i(getClass().getName(), "easdfdf" + e.toString());
}
}
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
try {
registerReceiver(mNetworkReceiver, new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION));
} catch (Exception e) {
Log.i(getClass().getName(), "easdfdfdd" + e.toString());
}
}
}
protected void unregisterNetworkChanges() {
try {
unregisterReceiver(mNetworkReceiver);
} catch (IllegalArgumentException e) {
e.printStackTrace();
}
}
@Override
public void onDestroy() {
super.onDestroy();
unregisterNetworkChanges();
}
每当Internet连接更改广播接收器onReceive方法时调用。
希望对您有帮助...