等待 5 秒

Question

我想等 5 秒再开始另一个 public void 方法。线程睡眠对我不起作用。如果有一种 wait() 不使用线程的方法，我很想知道。

public void check(){
    //activity of changing background color of relative layout
}

我想等 3 秒再更改相对布局颜色。

Answer 1

看看这是否适合您。请务必导入 android.os.Handler

      Handler handler = new Handler();
            handler.postDelayed(new Runnable() {
                public void run() {
                    // yourMethod();
                }
            }, 5000);   //5 seconds

Answer 2

您可以使用 java 处理程序来完成您的任务：

Handler handler = new Handler();
handler.postDelayed(new Runnable() {
    public void run() {
     // Actions to do after 5 seconds
    }
}, 5000);

有关详细信息，请阅读以下内容 url：

https://developer.android.com/reference/android/os/Handler.html

Answer 3

只需添加一行 lambda

(new Handler()).postDelayed(this::yourMethod, 5000);

编辑澄清：yourMethod指的是您要在 5000 毫秒后执行的方法。

Answer 4

我已将发布到另一个问题，但它也可能对您有所帮助。

Class:

import android.os.Handler;
import android.os.Looper;

public class Waiter {

WaitListener waitListener;
int waitTime = 0;
Handler handler;
int waitStep = 1000;
int maxWaitTime = 5000;
boolean condition = false;

public Waiter(Looper looper, final int waitStep, final int maxWaitTime){

    handler = new Handler(looper);
    this.waitStep = waitStep;
    this.maxWaitTime = maxWaitTime;

}

public void start(){

    handler.post(new Runnable() {
        @Override
        public void run() {

            waitListener.checkCondition();

            if (condition) {

                waitListener.onConditionSuccess();

            } else {
                if (waitTime <= maxWaitTime) {

                    waitTime += waitStep;
                    handler.postDelayed(this, waitStep);

                } else {

                    waitListener.onWaitEnd();
                }
            }
        }
    });

}

public void setConditionState(boolean condition){
    this.condition = condition;
}

public void setWaitListener(WaitListener waitListener){
    this.waitListener = waitListener;
}

}

接口：

public interface WaitListener {

public void checkCondition();

public void onWaitEnd();

public void onConditionSuccess();

}

用法示例：

ConnectivityManager mConnMgr = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
final int result = mConnMgr.startUsingNetworkFeature(ConnectivityManager.TYPE_MOBILE, "enableMMS");

final Waiter waiter = new Waiter(getMainLooper(), 1000, 5000);
waiter.setWaitListener(new WaitListener() {

            @Override
            public void checkCondition() {
                Log.i("Connection", "Checking connection...");
                NetworkInfo networkInfo = mConnMgr.getNetworkInfo(ConnectivityManager.TYPE_MOBILE_MMS);
                waiter.setConditionState(networkInfo.isConnected());
            }

            @Override
            public void onWaitEnd() {
                Log.i("Connection", "No connection for sending");
                //DO
            }

            @Override
            public void onConditionSuccess() {
                Log.i("Connection", "Connection success, sending...");
                //DO
            }

});

waiter.start();

Answer 5

导入使用：import android.os.Handler;

new Handler().postDelayed(new Runnable() {
    public void run() {
        // yourMethod();
    }
}, 5000); // 5 seconds

Answer 6

This works for me:

    val handler = Handler()
    handler.postDelayed({
        // your code to run after 2 second
    }, 2000)

Answer 7

我比较喜欢的是

(new Handler()).postDelayed(this::here is your method,2000);

等待 5 秒

Wait for 5 seconds

android

wait