打开activity的方法有以下几种:
使用显式Intent打开目标Activity:Intent intent = new Intent(CurrentActivity.this, TargetActivity.class);startActivity(intent);使用隐式Intent打开目标Activity:Intent intent = new Intent();intent.setAction("com.example.ACTION_TARGET_ACTIVITY");startActivity(intent);使用Intent传递数据到目标Activity:Intent intent = new Intent(CurrentActivity.this, TargetActivity.class);intent.putExtra("key", value);startActivity(intent);使用startActivityForResult()方法打开目标Activity,并获取返回结果:Intent intent = new Intent(CurrentActivity.this, TargetActivity.class);startActivityForResult(intent, REQUEST_CODE);使用FLAG_ACTIVITY_NEW_TASK标记打开目标Activity:Intent intent = new Intent(CurrentActivity.this, TargetActivity.class);intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);startActivity(intent);使用PendingIntent打开目标Activity:Intent intent = new Intent(CurrentActivity.this, TargetActivity.class);PendingIntent pendingIntent = PendingIntent.getActivity(CurrentActivity.this, requestCode, intent, PendingIntent.FLAG_UPDATE_CURRENT);pendingIntent.send(); 
