If you want a static share Intent
(i.e., it never changes), then you update your onCreateOptionsMenu
to be
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.mainpage, menu);
MenuItem item = menu.findItem(R.id.menu_item_share);
mShareActionProvider = (ShareActionProvider) item.getActionProvider();
// Create the share Intent
String playStoreLink = "https://play.google.com/store/apps/details?id=" +
getPackageName();
String yourShareText = "Install this app " + playStoreLink;
Intent shareIntent = ShareCompat.IntentBuilder.from(this)
.setType("text/plain").setText(yourShareText).getIntent();
// Set the share Intent
mShareActionProvider.setShareIntent(shareIntent);
return true;
}