判断有处理Intent的Activity
PackageManager packageManager = getPackageManager(); List<ResolveInfo> activities = packageManager.queryIntentActivities(mapIntent, 0); boolean isIntentSafe = activities.size() > 0; // Start an activity if it's safe if (isIntentSafe) { startActivity(mapIntent); }
將可以處理Intent的所有app列表做成下拉選擇框的形式
Intent intent = new Intent(Intent.ACTION_SEND); // Always use string resources for UI text. // This says something like "Share this photo with" String title = getResources().getString(R.string.chooser_title); // Create and start the chooser Intent chooser = Intent.createChooser(intent, title); startActivity(chooser);