android - webview downloading app but no downloading

Question

i am noob in webview app and and java too

i want to create a webview-app for downloading website eg-downloadgram.com website but but after loading the photo it is not starting download. pls tell me the solution.

  <uses-permission
    android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission
    android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission
    android:name="android.permission.INTERNET" />

my website let example -- downloadgram.com
my mainactivity.java is

public class MainActivity extends AppCompatActivity {
private WebView mywebView;
private static final String TAG = "MainActivity";
private static final int REQUEST_CODE=2;.

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    mywebView=(WebView) findViewById(R.id.webview);
    mywebView.setWebViewClient(new WebViewClient());
    WebSettings webSettings=mywebView.getSettings();
    mywebView.getSettings().setJavaScriptEnabled(true);
    mywebView.getSettings().setJavaScriptCanOpenWindowsAutomatically(true);
    mywebView.getSettings().setDomStorageEnabled(true);
    mywebView.setWebChromeClient(new WebChromeClient());
    mywebView.setWebViewClient(new WebViewClient());
    mywebView.loadUrl("https://downloadgram.com/");
    isWriteStoragePermissionGranted();
}
public class mywebClient extends WebViewClient{
    @Override
    public void onPageStarted(WebView view, String url, Bitmap favicon){
        super.onPageStarted(view,url,favicon);
    }
    @Override
    public boolean shouldOverrideUrlLoading(WebView view,String url){
        view.loadUrl(url);
        return true;
    }
}
@Override
public void onBackPressed(){
    if(mywebView.canGoBack()) {
        mywebView.goBack();
    }
    else{
        super.onBackPressed();
    }
}
public  boolean isReadStoragePermissionGranted() {
    if (Build.VERSION.SDK_INT >= 23) {
        if (checkSelfPermission(Manifest.permission.READ_EXTERNAL_STORAGE)
                == PackageManager.PERMISSION_GRANTED) {
            Log.v(TAG,"Permission is granted1");
            return true;
        } else {

            Log.v(TAG,"Permission is revoked1");
            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, 3);
            return false;
        }
    }
    else { 
        Log.v(TAG,"Permission is granted1");
        return true;
    }
}
public  boolean isWriteStoragePermissionGranted() {
    if (Build.VERSION.SDK_INT >= 23) {
        if (checkSelfPermission(android.Manifest.permission.WRITE_EXTERNAL_STORAGE)
                == PackageManager.PERMISSION_GRANTED) {
            Log.v(TAG,"Permission is granted2");
            return true;
        } else {
            Log.v(TAG,"Permission is revoked2");
            ActivityCompat.requestPermissions(this, new String[]      {Manifest.permission.WRITE_EXTERNAL_STORAGE}, 2);
            return false;
        }
    }
    else { 
        Log.v(TAG,"Permission is granted2");
        return true;
    }
}

}

why there is problem in download...?? pls give me a solution...

Answer 1

You need to add DownloadListener to Webview to fetch the download link from Webview, Then pass the download link to DownloadManager

mywebView.setDownloadListener(new DownloadListener() {
    public void onDownloadStart(String url, String userAgent,
                String contentDisposition, String mimetype,
                long contentLength) {
        DownloadManager.Request request = new DownloadManager.Request(
                Uri.parse(url));

        request.allowScanningByMediaScanner();
        request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
        request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, "newImage.jpg");//replace newImage.jpg
        DownloadManager dm = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
        dm.enqueue(request);
        Toast.makeText(getApplicationContext(), "File downloading",Toast.LENGTH_LONG).show();
    }
});