Android WebView not loading Mixed Content

Since Pie (API 29), all non-HTTPS traffic in app is now disabled by default.

If you're targeting API level 26 or above, you must first enable it in the manifest file. Add

android:usesCleartextTraffic="true"

into <application> tag.

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Since Lollipop (API 21), WebView blocks all mixed content by default.

To change this behaviour, when you are targeting API level 21 or above, use:

webView.getSettings().setMixedContentMode(WebSettings.MIXED_CONTENT_COMPATIBILITY_MODE);

In this mode, the WebView will attempt to be compatible with the approach of a modern web browser with regard to mixed content. Some insecure content may be allowed to be loaded by a secure origin and other types of content will be blocked. The types of content are allowed or blocked may change release to release and are not explicitly defined.

In practice this should allow loading of images, videos, music etc. - all content that has low probability of being major security threat, when tampered/replaced by malicious third-party.

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Alternatively use (strongly discouraged):

webView.getSettings().setMixedContentMode(WebSettings.MIXED_CONTENT_ALWAYS_ALLOW);

In this mode, the WebView will allow a secure origin to load content from any other origin, even if that origin is insecure. This is the least secure mode of operation for the WebView, and where possible apps should not set this mode.

If your min API is less than 21 and cannot call setMixedContentMode directly, you can use reflection:

try {
    Method m = WebSettings.class.getMethod("setMixedContentMode", int.class);
    if ( m == null ) {
        Log.e("WebSettings", "Error getting setMixedContentMode method");
    }
    else {
        m.invoke(webView.getSettings(), 2); // 2 = MIXED_CONTENT_COMPATIBILITY_MODE
        Log.i("WebSettings", "Successfully set MIXED_CONTENT_COMPATIBILITY_MODE");
    }
}
catch (Exception ex) {
    Log.e("WebSettings", "Error calling setMixedContentMode: " + ex.getMessage(), ex);
}