我将把你的问题分成两部分
1) 显示对话框并记住用户是否选择不再显示它
一个带有共享偏好的简单警报对话框可以做到这一点。
private void handleAlertDialog() {
//Handle showAlert
//check if allow to show dialog
if (!getSharedPreferences("MyPrefsFile1", MODE_PRIVATE)
.getBoolean("ShowDialog", false)) {
final CharSequence[] items = {"Would like to Remember this setting ? "};
AlertDialog dialog = new AlertDialog.Builder(WebViewActivity.this)
.setTitle("Allow location access")
.setMultiChoiceItems(items, null, new DialogInterface.OnMultiChoiceClickListener() {
@Override
public void onClick(DialogInterface dialog, int indexSelected, boolean isChecked) {
if (isChecked) {
//If the user checked the item, add it to the selected items
// Don't Allow, remember
getSharedPreferences("MyPrefsFile1", MODE_PRIVATE)
.edit()
.putBoolean("ShowDialog", true).commit();
Toast.makeText(getApplicationContext(), "Remember", Toast.LENGTH_SHORT).show();
} else {
getSharedPreferences("MyPrefsFile1", MODE_PRIVATE)
.edit()
.putBoolean("ShowDialog", false).commit();
Toast.makeText(getApplicationContext(), "Don't Remember", Toast.LENGTH_SHORT).show();
}
}
}).setPositiveButton("OK", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int id) {
// Your code when user clicked on OK
// You can write the code to save the selected item here
}
}).setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int id) {
// Your code when user clicked on Cancel
}
}).create();
dialog.show();
}
}
2) 从 javascript 触发此方法。
shouldOverrideUrlLoading(WebView view, String url) 在 Android N 显示您还需要覆盖 shouldOverrideUrlLoading(WebView view, WebResourceRequest request) 后已弃用。
一个完整的 WebViewClient 类将如下所示。
/**
* WebViewClient subclass loads all hyperlinks in the existing WebView
*/
public class GeoWebViewClient extends WebViewClient {
Dialog loadingDialog = new Dialog(WebViewActivity.this);
@SuppressWarnings("deprecation")
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
if (url.startsWith("mailto:")) {
//Handle mail Urls
startActivity(new Intent(Intent.ACTION_SENDTO, Uri.parse(url)));
} else if (url.startsWith("tel:")) {
//Handle telephony Urls
startActivity(new Intent(Intent.ACTION_DIAL, Uri.parse(url)));
} else if (url.startsWith("showalert:")) {
handleAlertDialog();
} else {
view.loadUrl(url);
}
return true;
}
@TargetApi(Build.VERSION_CODES.N)
@Override
public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {
final Uri uri = request.getUrl();
if (uri.toString().startsWith("mailto:")) {
//Handle mail Urls
startActivity(new Intent(Intent.ACTION_SENDTO, uri));
} else if (uri.toString().startsWith("tel:")) {
//Handle telephony Urls
startActivity(new Intent(Intent.ACTION_DIAL, uri));
} else if (uri.toString().startsWith("showalert:")) {
//Handle Alert
handleAlertDialog();
} else {
//Handle Web Urls
view.loadUrl(uri.toString());
}
return true;
}
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
super.onPageStarted(view, url, favicon);
webViewPreviousState = PAGE_STARTED;
if (loadingDialog == null || !loadingDialog.isShowing())
loadingDialog = ProgressDialog.show(WebViewActivity.this, "",
"Loading Please Wait", true, true,
new DialogInterface.OnCancelListener() {
@Override
public void onCancel(DialogInterface dialog) {
// do something
}
});
loadingDialog.setCancelable(false);
}
@RequiresApi(api = Build.VERSION_CODES.M)
@Override
public void onReceivedError(WebView view, WebResourceRequest request,
WebResourceError error) {
if (isConnected()) {
final Snackbar snackBar = Snackbar.make(rootView, "onReceivedError : " + error.getDescription(), Snackbar.LENGTH_INDEFINITE);
snackBar.setAction("Reload", new View.OnClickListener() {
@Override
public void onClick(View view) {
webView.loadUrl("javascript:window.location.reload( true )");
}
});
snackBar.show();
} else {
final Snackbar snackBar = Snackbar.make(rootView, "No Internet Connection ", Snackbar.LENGTH_INDEFINITE);
snackBar.setAction("Enable Data", new View.OnClickListener() {
@Override
public void onClick(View view) {
startActivityForResult(new Intent(Settings.ACTION_WIRELESS_SETTINGS), 0);
webView.loadUrl("javascript:window.location.reload( true )");
snackBar.dismiss();
}
});
snackBar.show();
}
super.onReceivedError(view, request, error);
}
@RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
@Override
public void onReceivedHttpError(WebView view,
WebResourceRequest request, WebResourceResponse errorResponse) {
if (isConnected()) {
final Snackbar snackBar = Snackbar.make(rootView, "HttpError : " + errorResponse.getReasonPhrase(), Snackbar.LENGTH_INDEFINITE);
snackBar.setAction("Reload", new View.OnClickListener() {
@Override
public void onClick(View view) {
webView.loadUrl("javascript:window.location.reload( true )");
}
});
snackBar.show();
} else {
final Snackbar snackBar = Snackbar.make(rootView, "No Internet Connection ", Snackbar.LENGTH_INDEFINITE);
snackBar.setAction("Enable Data", new View.OnClickListener() {
@Override
public void onClick(View view) {
startActivityForResult(new Intent(Settings.ACTION_WIRELESS_SETTINGS), 0);
webView.loadUrl("javascript:window.location.reload( true )");
snackBar.dismiss();
}
});
snackBar.show();
}
super.onReceivedHttpError(view, request, errorResponse);
}
@Override
public void onPageFinished(WebView view, String url) {
if (webViewPreviousState == PAGE_STARTED) {
if (null != loadingDialog) {
loadingDialog.dismiss();
loadingDialog = null;
}
}
}
}
isConnected方法用于检查网络连接
/**
* Check if there is any connectivity
*
* @return is Device Connected
*/
public boolean isConnected() {
ConnectivityManager cm = (ConnectivityManager)
this.getSystemService(Context.CONNECTIVITY_SERVICE);
if (null != cm) {
NetworkInfo info = cm.getActiveNetworkInfo();
return (info != null && info.isConnected());
}
return false;
}
如您所见，我添加了一个过滤器来检查以showalert: 开头的 URL。如果我的 Web 客户端类捕获到任何以 showalert 开头的 URL，那么它会触发 handleAlert 方法。
结果
2) 从 javascript 触发此方法。
shouldOverrideUrlLoading(WebView view, String url) 在 Android N 显示您还需要覆盖 shouldOverrideUrlLoading(WebView view, WebResourceRequest request) 后已弃用。
一个完整的 WebViewClient 类将如下所示。
/**
* WebViewClient subclass loads all hyperlinks in the existing WebView
*/
public class GeoWebViewClient extends WebViewClient {
Dialog loadingDialog = new Dialog(WebViewActivity.this);
@SuppressWarnings("deprecation")
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
if (url.startsWith("mailto:")) {
//Handle mail Urls
startActivity(new Intent(Intent.ACTION_SENDTO, Uri.parse(url)));
} else if (url.startsWith("tel:")) {
//Handle telephony Urls
startActivity(new Intent(Intent.ACTION_DIAL, Uri.parse(url)));
} else if (url.startsWith("showalert:")) {
handleAlertDialog();
} else {
view.loadUrl(url);
}
return true;
}
@TargetApi(Build.VERSION_CODES.N)
@Override
public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {
final Uri uri = request.getUrl();
if (uri.toString().startsWith("mailto:")) {
//Handle mail Urls
startActivity(new Intent(Intent.ACTION_SENDTO, uri));
} else if (uri.toString().startsWith("tel:")) {
//Handle telephony Urls
startActivity(new Intent(Intent.ACTION_DIAL, uri));
} else if (uri.toString().startsWith("showalert:")) {
//Handle Alert
handleAlertDialog();
} else {
//Handle Web Urls
view.loadUrl(uri.toString());
}
return true;
}
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
super.onPageStarted(view, url, favicon);
webViewPreviousState = PAGE_STARTED;
if (loadingDialog == null || !loadingDialog.isShowing())
loadingDialog = ProgressDialog.show(WebViewActivity.this, "",
"Loading Please Wait", true, true,
new DialogInterface.OnCancelListener() {
@Override
public void onCancel(DialogInterface dialog) {
// do something
}
});
loadingDialog.setCancelable(false);
}
@RequiresApi(api = Build.VERSION_CODES.M)
@Override
public void onReceivedError(WebView view, WebResourceRequest request,
WebResourceError error) {
if (isConnected()) {
final Snackbar snackBar = Snackbar.make(rootView, "onReceivedError : " + error.getDescription(), Snackbar.LENGTH_INDEFINITE);
snackBar.setAction("Reload", new View.OnClickListener() {
@Override
public void onClick(View view) {
webView.loadUrl("javascript:window.location.reload( true )");
}
});
snackBar.show();
} else {
final Snackbar snackBar = Snackbar.make(rootView, "No Internet Connection ", Snackbar.LENGTH_INDEFINITE);
snackBar.setAction("Enable Data", new View.OnClickListener() {
@Override
public void onClick(View view) {
startActivityForResult(new Intent(Settings.ACTION_WIRELESS_SETTINGS), 0);
webView.loadUrl("javascript:window.location.reload( true )");
snackBar.dismiss();
}
});
snackBar.show();
}
super.onReceivedError(view, request, error);
}
@RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
@Override
public void onReceivedHttpError(WebView view,
WebResourceRequest request, WebResourceResponse errorResponse) {
if (isConnected()) {
final Snackbar snackBar = Snackbar.make(rootView, "HttpError : " + errorResponse.getReasonPhrase(), Snackbar.LENGTH_INDEFINITE);
snackBar.setAction("Reload", new View.OnClickListener() {
@Override
public void onClick(View view) {
webView.loadUrl("javascript:window.location.reload( true )");
}
});
snackBar.show();
} else {
final Snackbar snackBar = Snackbar.make(rootView, "No Internet Connection ", Snackbar.LENGTH_INDEFINITE);
snackBar.setAction("Enable Data", new View.OnClickListener() {
@Override
public void onClick(View view) {
startActivityForResult(new Intent(Settings.ACTION_WIRELESS_SETTINGS), 0);
webView.loadUrl("javascript:window.location.reload( true )");
snackBar.dismiss();
}
});
snackBar.show();
}
super.onReceivedHttpError(view, request, errorResponse);
}
@Override
public void onPageFinished(WebView view, String url) {
if (webViewPreviousState == PAGE_STARTED) {
if (null != loadingDialog) {
loadingDialog.dismiss();
loadingDialog = null;
}
}
}
}
isConnected方法用于检查网络连接
/**
* Check if there is any connectivity
*
* @return is Device Connected
*/
public boolean isConnected() {
ConnectivityManager cm = (ConnectivityManager)
this.getSystemService(Context.CONNECTIVITY_SERVICE);
if (null != cm) {
NetworkInfo info = cm.getActiveNetworkInfo();
return (info != null && info.isConnected());
}
return false;
}
如您所见，我添加了一个过滤器来检查以showalert: 开头的 URL。如果我的 Web 客户端类捕获到任何以 showalert 开头的 URL，那么它会触发 handleAlert 方法。
结果