所以我下面有下面的代码,它基本上获取初始电池电量,等待一定的时间,并获取calculateHelper内部的最终电池电量,然后找到差异并打印出来。
// Get the initial battery level
IntentFilter ifilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
Intent batteryStatus = this.registerReceiver(null, ifilter);
int level = batteryStatus.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
System.out.println("Initial battery level is: " + level);
int scale = batteryStatus.getIntExtra(BatteryManager.EXTRA_SCALE, -1);
final float batteryPctTemp0 = level / (float) scale;
final float batteryPct0 = batteryPctTemp0 * 100;
int waitTime = 60000 * interval; // 1 minute is 60000 miliseconds
System.out.println("Wait time is " + waitTime);
Runnable r = new Runnable() {
@Override
public void run(){
calculateHelper(batteryPct0,startButton);
}
};
Handler h = new Handler();
h.postDelayed(r, waitTime);
我想无限循环(直到程序退出)整个过程,以便在每个连续的线程完成后,下一个线程开始,每次都获取新的初始电池电量并将其传递到calculateHelper函数中以计算新的差异。我不希望线程堆积起来。我一次想要一个线程。换句话说,循环需要等待线程完成才能启动另一个循环。
我一辈子都不知道该怎么做!如果我把整个事情放在一段时间内,它只会反复打开线程,导致手机崩溃。
如果有人能在这件事上为我指明正确的方向,我将不胜感激。另外,如果需要更多代码来解决问题,只需发表评论,我会在将其添加到我的问题后立即回复。
谢谢。
<小时/>感谢 Whooper,我添加了这种在循环中调节执行顺序的方法。但是,由于某种原因,我的 postExecute() 方法从未被执行,也没有发生任何事情。
private class BatteryLifeTask extends AsyncTask<Void, Void, Void> {
// Member variables
Context appContext;
float batteryPct0;
Button startButton;
public BatteryLifeTask(Context context, Button start) {
super();
appContext = context;
startButton = start;
}
protected Void doInBackground(Void... params) {
// Get the initial battery level
IntentFilter ifilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
Intent batteryStatus = appContext.registerReceiver(null, ifilter);
int level = batteryStatus.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
System.out.println("Initial battery level is: " + level);
int scale = batteryStatus.getIntExtra(BatteryManager.EXTRA_SCALE, -1);
final float batteryPctTemp0 = level / (float) scale;
batteryPct0 = batteryPctTemp0 * 100;
return null;
}
protected void onPostExecute() {
int waitTime = 60000 * interval; // 1 minute is 60000 miliseconds
System.out.println("In postExecute. waitTime is" + waitTime);
Runnable r = new Runnable() {
@Override
public void run(){
System.out.println("An interval has passed.");
calculateHelper(batteryPct0,startButton);
new BatteryLifeTask(appContext,startButton).execute();
}
};
Handler h = new Handler();
h.postDelayed(r, waitTime);
}
}
以及我对执行方法的调用:
// Start the task loop
new BatteryLifeTask(getApplicationContext(), startButton).execute();
<小时/>
我发现了问题:
我忘记设置@Override注释,这个答案:https://stackoverflow.com/a/11127996/2247192状态:
"If your params of onPostExecute(Param param) don't match the one you defined with extends AsyncTask<...,...,Param> and you didn't use the @Override annotation, it will never be executed and you don't get a warning from Eclipse."
所以我将 postExecute 方法更正为:
@Override
protected void onPostExecute(Void aVoid) {
super.onPostExecute(aVoid);
int waitTime = 60000 * interval; // 1 minute is 60000 miliseconds
System.out.println("In postExecute. waitTime is " + waitTime);
Runnable r = new Runnable() {
@Override
public void run(){
System.out.println("An interval has passed.");
calculateHelper(batteryPct0,startButton);
new BatteryLifeTask(appContext,startButton).execute();
}
};
Handler h = new Handler();
h.postDelayed(r, waitTime);
}
所有问题现已解决。
最佳答案
尝试使用 AsyncTask。 http://developer.android.com/reference/android/os/AsyncTask.html
这样你就可以在调用 onPostExecute() 时再次执行任务。
类似这样的事情:
private class BatteryLifeTask extends AsyncTask<Void, Void, Void> {
protected void doInBackground(Void... params) {
// Get the initial battery level
IntentFilter ifilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
Intent batteryStatus = this.registerReceiver(null, ifilter);
int level = batteryStatus.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
System.out.println("Initial battery level is: " + level);
int scale = batteryStatus.getIntExtra(BatteryManager.EXTRA_SCALE, -1);
final float batteryPctTemp0 = level / (float) scale;
final float batteryPct0 = batteryPctTemp0 * 100;
}
protected void onPostExecute() {
int waitTime = 60000 * interval; // 1 minute is 60000 miliseconds
Runnable r = new Runnable() {
@Override
public void run(){
new BatteryLifeTask.execute();
}
};
Handler h = new Handler();
h.postDelayed(r, waitTime);
}
}
请注意,此代码未经测试。但我希望它能给你一个想法:-)
关于java - Android - 如何连续运行一个线程,一个接一个,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/27820764/