Webview isn't opening select html components (dropdown) when initiating it with application context

Question

I'm loading a WebView with application context, in the background, so that when the activity opens, we won't have a time delay of loading the webview.

I have a very simple html file, loaded in the webview, with select component :

<select>
  <option value="name1">value1</option>
  <option value="name2">value2</option>
  <option value="name3">value3</option>
</select>

I initiate the webview in the background, with application context

WebView webView = new WebView(getApplicationContext());
webView.setJavaScriptEnabled(true);
webview.loadUrl("https://www.google.com");

And open it in the activity once its ready :

LinearLayout root = new LinearLayout(this);
root.setLayoutParams(new LinearLayout.LayoutParams(
       LinearLayout.LayoutParams.MATCH_PARENT, 
       LinearLayout.LayoutParams.MATCH_PARENT));
root.setOrientation(LinearLayout.VERTICAL);
root.addView(webView);
setContentView(root);

The webview opens in the activity, BUT, the select components don't open the alert, for picking from the dropdown. The reason for it is - Alert only works with an activity context.

Here's what i tried so far :

Trying to update the context of a view is not possible.
Coping a view - not possible.
Initiating the webview with another activity, and passing it to my current activity - doesn't work as well.
Tried calling invalidate, reload - doesn't work.
Init WebView in onCreate() of activity : WebView webView = new WebView(this); this works, but it takes time for the webview to load, and its not my intention.
The fact that i'm loading the WebView programmatically, and not setting it with xml layout - it's not the problem here.
i saw this solution already : https://stackoverflow.com/a/28030088/5130239 , it didn't work either.

I want to stress out, that a solution of sort : don't load the webview in the background is not possible for me, so please, don't suggest it, i'm looking for something that fits my requirements.

score 5 · Accepted Answer · answered Dec 21 '17 at 10:10

Turns out that a WebView (or any other ui component) doesn't work when setting the context to application context.

Doesn't work :

WebView webView = new WebView(getApplicationContext());

Works :

WebView webView = new WebView(CUURENT_ACTIVITY);

We don't want to use the CURENT_ACTIVITY when using MutableContextWrapper, which solves the issue (init the WebView with application context, and when the activity opens, we're updating the context with activity context).

InternalContext class :

class InternalContext {

    private static InternalContext instance;
    private MutableContextWrapper mutableContext;

    protected static InternalContext getInstance() {
        if (instance == null) {
            instance = new InternalContext();
        }

        return instance;
    }

    protected void setBaseContext(Context context) {
        mutableContext.setBaseContext(context.getApplicationContext());
    }

    protected MutableContextWrapper getMutableContext() {
        return mutableContext;
    }
}

When initiating the webview, we're using the mutableContext :

WebView webView = new WebView(InternalContext.getInstance().getMutableContext());

When a new activity starts, we need to update the base context :

InternalContext.getInstance().setBaseContext(CURRENT_ACTIVITY);

I had the same issue and this was one solution. Another solution was that I did my WebView on the activity's xml file. — Gonzalo Ledezma Torres, Dec 29 '17 at 15:20
that doesn't work in this case, because i wanted to load the webview in the background, while switching activities, so the xml is no longer valid — Dus, Jan 01 '18 at 08:50
@Dus I am still struggling with this issue, can you please share your source code for me to refer — sasi, Dec 02 '21 at 12:31

Webview isn't opening select html components (dropdown) when initiating it with application context

1 Answers1