安装APK：
public static void installApp(Context context, String packageName) {
try {
PackageInfo pi = context.getPackageManager().getPackageInfo(packageName, 0);
Intent resolveIntent = new Intent(Intent.ACTION_MAIN, null);
resolveIntent.addCategory(Intent.CATEGORY_LAUNCHER);
resolveIntent.setPackage(pi.packageName);
List<ResolveInfo> apps = context.getPackageManager().queryIntentActivities(resolveIntent, 0);
if (!apps.isEmpty()) {
ResolveInfo ri = apps.get(0);
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.setComponent(new ComponentName(ri.activityInfo.packageName, ri.activityInfo.name));
context.startActivity(intent);
}
} catch (NameNotFoundException e) {
// no-op
}
}
一些用到的细节:
Intent的setPackage 可以限制 Intent只能投递到某个Package内的Component.
/**
* (Usually optional) Set an explicit application package name that limits
* the components this Intent will resolve to. If left to the default
* value of null, all components in all applications will considered.
* If non-null, the Intent can only match the components in the given
* application package.
*
* @param packageName The name of the application package to handle the
* intent, or null to allow any application package.
*
* @return Returns the same Intent object, for chaining multiple calls
* into a single statement.
*
* @see #getPackage
* @see #resolveActivity
*/
public Intent setPackage(String packageName) {}
Intent的setComponent则限制Intent只能投递给某个Component， 和setClass干的事情一样，setClass的注释也说了:
* Convenience for calling {@link #setComponent(ComponentName)} with the
* name returned by a {@link Class} object.
ResolveInfo内部封装了对Intent解析<通过queryIntentActivities>出来的相关的Activity的info:ActivityInfo
