android - 如果值为 null 等待 android 中的运行函数

Question

我运行一个类 LokasyonBulucu()

LokasyonBulucu lokasyonBulucu= new LokasyonBulucu();
lokasyonBulucu.LokasyonBul(context);

我从这个类中获取两个变量 lat 和 lon

lat=lokasyonBulucu.location.getLatitude();
lon= lokasyonBulucu.location.getLongitude();

但我想等待类(class)找到坐标...因为这需要很多时间。如果它找到纬度和经度我想运行这个函数

new arkaPlanIsleri(kategori_id, lat , lon).execute();

Answer 1

使用 for 循环检查每一秒是否有最大等待秒数。每秒检查一次 lat 和 lon 是否已找到。如果是，则执行该方法并跳出等待循环:

for(int i = 0; i < 10; i++) { //maximum 10 seconds to wait
    if(lat != null && lon != null) { //check if the lat and lon are already found
        new arkaPlanIsleri(kategori_id, lat , lon).execute();
        break; //stop the waiting loop
    }
    SystemClock.sleep(1000); //wait one second
}