Launch app with URL

问题:

I've read about intents in android but here goes my question. I'd like to launch an app on my android phone with the click of a link in the web browser. Example: If the link is "mycam://http://camcorder.com", "mycam://" acts as some kind of "tag" to launch my app but I'd like to pass "http://camcorder.com" as a string to that app on start.

Help please!

Thanks!

回答1:

There is a method in the Browser app source code, :

public boolean shouldOverrideUrlLoading(WebView view, String url) { ... }

After a url clicked and it's not yet starting to load:

1. converts the url to intent

   Intent intent;
   
   // perform generic parsing of the URI to turn it into an Intent.
   try {
       intent = Intent.parseUri(url, Intent.URI_INTENT_SCHEME);
   } catch (URISyntaxException ex) {
       Log.w("Browser", "Bad URI " + url + ": " + ex.getMessage());
       return false;
   }
   

2. if it don't start with market:// (or some predefined schemes), try startActivityIfNeeded()

   intent.addCategory(Intent.CATEGORY_BROWSABLE);
   intent.setComponent(null);
   try {
       if (startActivityIfNeeded(intent, -1)) {
           return true;
       }
   } catch (ActivityNotFoundException ex) {
       // ignore the error. If no application can handle the URL,
       // eg about:blank, assume the browser can handle it.
   }
   

It's very useful information! I re-play the situation in some simple code:

Intent intent = Intent.parseUri("mycam://http://camcorder.com", Intent.URI_INTENT_SCHEME);
intent.addCategory(Intent.CATEGORY_BROWSABLE);
intent.setComponent(null);
System.out.println(intent);

The result will provide clues for me to write an activity with the intent-filter:

        <activity android:name=".MyCamActivity" android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
            <intent-filter>
                <action android:name="android.intent.action.VIEW" />
                <category android:name="android.intent.category.DEFAULT" />
                <category android:name="android.intent.category.BROWSABLE" />
                <data android:scheme="mycam" />
            </intent-filter>
        </activity>

PS. don't forget the android.intent.category.DEFAULT.

Finally, your Activity can invoke by mycam://yourscheme.

回答2:

mycam://http://camcorder.com isn't a valid URI, and making up schemes is kind of scary if two apps pick the same one. It would be better for you to register your activity as a handler for a particular URI (for example http://www.example.com/camcorder, substituting your own domain of course). You do that with the <data> tag in your <intent-filter> tag in the AndroidManifest.xml. When the user clicks the link, they'll be taken to your application. That way, you can also put a real page there on the web, instructing people to install your app or whatever.