Android Question Simple OSM Viewer

[Sergey_New]

Using the example made a small application for B4A.
It works well on the emulator, but, unfortunately, on the device, the "+" and "-" buttons are very small. Clicking on them doesn't work. Gestures works.
What can be changed?

 

[Sergey_New]

No one knows?
Has anyone tested the attached example and the result is the same?

 

[agraham]

Just shows a blank screen on my Redmi Note 9 Pro.

 

[Sergey_New]

Dont clear. There is currently a map with London detection on my Samsung S7.

 

[agraham]

Also just a blank screen on both my Pixel 4a and Surface Duo as well!

 

[Sergey_New]

Everything is displayed on my emulator and on the device. I do not understand what is going on?

 

[asales]

Tested in Samsung A71 and Redmi 9A.
Both show a blank screen.

 

[bparent]

Using the example made a small application for B4A.
It works well on the emulator, but, unfortunately, on the device, the "+" and "-" buttons are very small. Clicking on them doesn't work. Gestures works.
What can be change

Shows London map on Samsung Ultra 21. +/- doesn't do anything, but zoom gesture works Have you put SetApplicationAttribute(android:usesCleartextTraffic, "true") in manifest project file?

 

[Sergey_New]

bparent, thank God, at least it works for you

Shows London map on Samsung Ultra 21. +/- doesn't do anything, but zoom gesture works Have

I have the same.

Have you put SetApplicationAttribute(android:usesCleartextTraffic, "true") in manifest project file?

No, I didn't put it in..
Added to the manifest - nothing has changed.
Checked the code in B4J. The scale is changed both by +/- and by the mouse wheel.
Attached the project on B4J.

 

[agraham]

I've never used WebView and I am no good on webby stuff but it seems that in B4A after WebView1.LoadHtml is called it raises the PageFinished event but with a Url of "file:///".

On the other hand the project on B4J works fine but it doesn't seem to raise the PageFinished event at all

I don't understand what's happening here

 

[agraham]

If you target SDK 27 it displays the map, although the +/- buttons don't seem to work. Target SDK 28 or higher and it doesn't work. I assume some permissions or other security was added at 28 but at the moment I haven't identified what it might be. You will need to uninstall the app before loading it to target a lower SDK.

Also nowadays it really should be using https rather than http - just add the 's' and it works anyway.

 

[DonManfred]

What can be changed?

You are using Javascript in the HTML but did not added any javascript possibility to your app?`WHY?

I get this message when using webviewextras

Uncaught ReferenceError: OpenLayers is not defined in file:/// (Line: 12)

Are you sure the javascript does work on android in a limited webview? Note that webview is not compareable with a Webbrowser on Android

 

[agraham]

Are you sure the javascript does work on android?

Yes - see above.

 

[agraham]

I'm probably wrong about just adding 's' to make it https working but I got it working targetting SDK 30 by adding ClearText to the manifest.

' 28 - Non-ssl (non-https) communication is not permitted by default.
' It can be enabled in B4A v9+ by adding this line to the manifest editor:
CreateResourceFromFile(Macro, Core.NetworkClearText)

 

[Sergey_New]

Are you sure the javascript does work on android in a limited webview?

Works for me.

You are using Javascript in the HTML but did not added any javascript possibility to your app?`WHY?

Tell me how to do it?

 

[agraham]

Tell me how to do it?

No need. See above.

 

[TILogistic]

?
You need to declare the css style sheet, also it is a very old api, the documentation is not online and you should download it from here.

OpenLayers 2

    <html>
    <head>
    <meta charset="utf-8" />
    <title>OpenStreetMap</title>
    <link rel="stylesheet" href="https://openlayers.org/api/2.13.1/theme/default/style.css" type="text/css">
    <style>html, body, #map {width: 100%;height: 100%;margin: 0;padding: 0;}</style>
    </head>
    <body>
      <div id="mapdiv"></div>
      <script src="https://openlayers.org/api/2.13.1/OpenLayers.js"></script>
      <script>
        map = new OpenLayers.Map("mapdiv");
        map.addLayer(new OpenLayers.Layer.OSM());
        var lonLat = new OpenLayers.LonLat(${CenterLong}, ${CenterLat})
              .transform(
                new OpenLayers.Projection("EPSG:4326"),
                map.getProjectionObject()
              );
        var markers = new OpenLayers.Layer.Markers( "Markers" );
        map.addLayer(markers);
        markers.addMarker(new OpenLayers.Marker(lonLat));
        map.setCenter (lonLat, ${zoom});
      </script>
    </body></html>

 

[TILogistic]

sorry.

Comment deleted.

 

[Sergey_New]

No need. See above.

What to watch?

 

[DonManfred]

What to watch?

@agraham said that it works if you set TargetSDK to 27. But it does not work on 30 and he has no answer for this.