blocks|key|1860187|text|您可以尝试这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1860188|public+boolean+onKeyDown(int+keyCode,+KeyEvent+event)+
{+++++++
++if(keyCode==KeyEvent.KEYCODE_BACK){
++++++++this.finish+();
++++++}
++++return+true;
}|code-block|syntax|javascript|1860189|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can try this:

<pre><code>public boolean onKeyDown(int keyCode, KeyEvent event) 
{ 
 if(keyCode==KeyEvent.KEYCODE_BACK){
 this.finish ();
 }
 return true;
}
</code></pre>

blocks|key|2480269|text|您想要覆盖OnkeyDown+&+finish活动|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2480270|@Override
public+boolean+onKeyDown(int+keyCode,+KeyEvent+event)++{
++++if+(keyCode+==+KeyEvent.KEYCODE_BACK+&&+event.getRepeatCount()+==+0)+{
++++++++//+do+something+on+back.
+++++++this.finish();
++++++++return+true;
++++}

++++return+super.onKeyDown(keyCode,+event);
}|code-block|syntax|javascript|2480271|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

u want to Override the OnkeyDown &amp; finish activity

<pre><code>@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
 if (keyCode == KeyEvent.KEYCODE_BACK &amp;&amp; event.getRepeatCount() == 0) {
 // do something on back.
 this.finish();
 return true;
 }

 return super.onKeyDown(keyCode, event);
}
</code></pre>

blocks|key|2480276|text|好的，为了启动你的设备的家庭监控，在你的onKeyDown()中使用以下代码|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2480277|@Override+
public+boolean+onKeyDown(int+keyCode,+KeyEvent+event)++{+
++++if+(keyCode+==+KeyEvent.KEYCODE_BACK+&&+event.getRepeatCount()+==+0)+{+
++++++++//+do+something+on+back.
++++++++Intent+startMain+=+new+Intent(Intent.ACTION_MAIN);+
++++++++startMain.addCategory(Intent.CATEGORY_HOME);+
++++++++startMain.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);+
++++++++startActivity(startMain);+

+++++++this.finish();+
++++++++return+true;+
++++}+

++++return+super.onKeyDown(keyCode,+event);+
}+|code-block|syntax|javascript|2480278|如果您想要关闭您的应用程序，那么我认为要么您必须以某种方式(某种标准方式)通过finish()关闭您的所有活动，要么使用|2480279|android.os.Process.killProcess(android.os.Process.myPid())这个代码会杀死你的应用程序。(一些丑陋的方式..)|2480280|entityMap^0|K|B|0|0|13|8|0|0|1M|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@]|E|$]]|$1|M|3|N|5|6|7|X|8|@$9|Y|A|Z|B|C]]|D|@]|E|$]]|$1|O|3|-4|5|6|7|10|8|@]|D|@]|E|$]]]|P|$]]

Ok, for launching Home sceen of your device use this code in your <code>onKeyDown()</code>

<pre><code>@Override 
public boolean onKeyDown(int keyCode, KeyEvent event) { 
 if (keyCode == KeyEvent.KEYCODE_BACK &amp;&amp; event.getRepeatCount() == 0) { 
 // do something on back.
 Intent startMain = new Intent(Intent.ACTION_MAIN); 
 startMain.addCategory(Intent.CATEGORY_HOME); 
 startMain.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); 
 startActivity(startMain); 

 this.finish(); 
 return true; 
 } 

 return super.onKeyDown(keyCode, event); 
} 
</code></pre>

And if you want to close your application then I think either you have to close your all activities by <code>finish()</code> in a manner (some standard way) or using

<code>android.os.Process.killProcess(android.os.Process.myPid())</code> this code kill your app. 
(Some ugly way..!)

blocks|key|2480298|text|按BACK键将有效地为您调用finish()。没有必要捕获后退密钥。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2480299|我假设你的问题是，当你按Back键时，它只是简单地返回到你应用程序中的前一个Activity。|2480300|如果是这种情况，那么当所有活动在你的应用程序中启动一个新的Activity时，让它们“自我终止”。|2480301|startActivity(new+Intent(this,+MyNewActivity.class));
finish();|code-block|syntax|javascript|2480302|如果你这样做，那么当你按下BACK时，将没有Activity可返回，它将始终返回到主屏幕。|2480303|entityMap^0|E|8|0|12|8|0|T|8|0|0|M|8|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|V|8|@$9|W|A|X|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|Y|8|@$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|J|3|K|5|L|7|11|8|@]|D|@]|E|$M|N]]|$1|O|3|P|5|6|7|12|8|@$9|13|A|14|B|C]]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|15|8|@]|D|@]|E|$]]]|R|$]]

Pressing the BACK key will effectively call <code>finish()</code> for you. There is no need to trap the BACK key.

I'm assuming your problem is that when you press the BACK key it is simply going back to the previous <code>Activity</code> in your app.

If that is the case then make all activities 'self-terminate' when they start a new <code>Activity</code> in your app....

<pre><code>startActivity(new Intent(this, MyNewActivity.class));
finish();
</code></pre>

If you do that then there will be no <code>Activity</code> to return to when you press BACK and it will always return to the home screen.

blocks|key|4591372|text|您应该重写finish()|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4591373|@Override
public+void+finish()+{
++++System.out.println("finish+activity");++++++
++++SaveData();+++++
++++System.runFinalizersOnExit(true)+;++++++++++
++++super.finish();
++++android.os.Process.killProcess(android.os.Process.myPid());
}|code-block|syntax|javascript|4591374|然后调用此方法，如下所示：|4591375|@Override
++++public+void+onBackPressed()+{
+++++this.finish();
++++}|4591376|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

You should override finish()

<pre><code>@Override
public void finish() {
 System.out.println("finish activity"); 
 SaveData(); 
 System.runFinalizersOnExit(true) ; 
 super.finish();
 android.os.Process.killProcess(android.os.Process.myPid());
}
</code></pre>

Then invoke this method like this:

<pre><code>@Override
 public void onBackPressed() {
 this.finish();
 }
</code></pre>

blocks|key|1860231|text|当您调用NewAcitivy时，请调用finish().After+startActivity，以便关闭之前的活动。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1860232|然后使用|1860233|@Override
++++public+void+onBackPressed()+{
++++++++super.onBackPressed();
++++++++this.finish();
++++}|code-block|syntax|javascript|1860234|entityMap^0|J|8|Y|D|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|T|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|U|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|V|8|@]|D|@]|E|$]]]|N|$]]

When you call NewAcitivy call <code>finish()</code>.After <code>startActivity</code> so the previous acitivity gets closed.

Then use 

<pre><code>@Override
 public void onBackPressed() {
 super.onBackPressed();
 this.finish();
 }
</code></pre>

blocks|key|4591433|text|简单的方法是，当你进入下一个活动时，只完成当前的活动。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4591434|只需在startActivity()之后执行finish()，然后从any活动中按回键，您可以简单地调用finish()从应用程序中退出，因为所有其他活动都不在堆栈中。|offset|length|style|CODE|4591435|entityMap^0|0|3|F|M|8|1G|8|0^^$0|@$1|2|3|4|5|6|7|J|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|K|8|@$D|L|E|M|F|G]|$D|N|E|O|F|G]|$D|P|E|Q|F|G]]|9|@]|A|$]]|$1|H|3|-4|5|6|7|R|8|@]|9|@]|A|$]]]|I|$]]

Easy way is to just finish the current activity when you are moving to the next activity.

Just do a <code>finish()</code> after your <code>startActivity()</code>, then on back press from the any activity you can simply call <code>finish()</code> to come out of the application as all the other activities are not there in the stack.

blocks|key|1860250|text|你可以试试这个|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1860251|@Override
public+void+onBackPressed()+{
++++++++Intent+startMain+=+new+Intent(Intent.ACTION_MAIN);++++++
++++++++startMain.addCategory(Intent.CATEGORY_HOME);++++++++++++++++++++++++
++++++++startMain.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);++++++++++
++++++++startActivity(startMain);+
++}|code-block|syntax|javascript|1860252|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can try this

<pre><code>@Override
public void onBackPressed() {
 Intent startMain = new Intent(Intent.ACTION_MAIN); 
 startMain.addCategory(Intent.CATEGORY_HOME); 
 startMain.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); 
 startActivity(startMain); 
 }
</code></pre>

blocks|key|6008371|text|您可以从任何位置关闭应用程序以调用此类型的意图：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|6008372|Intent+intent+=+new+Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);|code-block|syntax|javascript|6008373|这是从任何地方、在任何单击事件上关闭应用程序的最佳方式|6008374|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

You can close application from anywhere to call this type of Intent:

<pre><code>Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
</code></pre>

This is the best way for close application from anywhere, on any click event

blocks|key|6008384|text|您需要使用一个标志来启动一个意图，以清除实际活动之上的活动。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|6008385|public+void+onBackPressed()+{
++++Intent+intent+=+new+Intent(this,+HomeActivity.class);
++++intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
++++this.startActivity(intent);
++++this.finish();
}|code-block|syntax|javascript|6008386|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You need to start an intent using a flag to clear the activities on top of the actual activity.

<pre><code>public void onBackPressed() {
 Intent intent = new Intent(this, HomeActivity.class);
 intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
 this.startActivity(intent);
 this.finish();
}
</code></pre>

blocks|key|4591539|text|引用官方|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4591540|FLAG_ACTIVITY_CLEAR_TOP|offset|length|style|BOLD|4591541|如果设置了|4591542|，并且正在启动的活动已经在当前任务中运行，则不是启动该活动的新实例，而是关闭它上面的所有其他活动，并且此意图将作为新意图传递给(现在在顶部)旧活动。|blockquote|4591543|4591544|4591545|FLAG_ACTIVITY_CLEAR_TASK|4591546|4591547|如果在传递给Context.startActivity()的意图中设置了此标志，则此标志将导致在启动活动之前清除与活动关联的任何现有任务。也就是说，该活动将成为其他空任务的新根，并且所有旧活动都将完成。这只能与FLAG_ACTIVITY_NEW_TASK一起使用。|4591548|4591549|4591550|FLAG_ACTIVITY_NO_HISTORY|4591551|4591552|如果设置，则新活动不会保留在历史记录堆栈中。一旦用户离开它，活动就结束了。这也可以使用noHistory属性来设置。|4591553|4591554|4591555|FLAG_ACTIVITY_NEW_TASK|4591556|4591557|如果设置，则此活动将成为此历史记录堆栈上新任务的开始。|4591558|4591559|4591560|@Override
public+void+onBackPressed()
{

++++++++++++++++Intent+intCloseApp+=+new+Intent(Intent.ACTION_MAIN);
++++++++++++++++intCloseApp.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
++++++++++++++++intCloseApp.addFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
++++++++++++++++intCloseApp.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
++++++++++++++++intCloseApp.addCategory(Intent.CATEGORY_HOME);
++++++++++++++++intCloseApp.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
++++++++++++++++startActivity(intCloseApp);
++}|code-block|syntax|javascript|4591561|entityMap^0|0|0|N|0|0|0|0|0|0|O|0|0|0|0|0|0|O|0|0|0|0|0|0|M|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|1G|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|1H|8|@$D|1I|E|1J|F|G]]|9|@]|A|$]]|$1|H|3|I|5|6|7|1K|8|@]|9|@]|A|$]]|$1|J|3|K|5|L|7|1L|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|1M|8|@]|9|@]|A|$]]|$1|N|3|-4|5|6|7|1N|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|1O|8|@$D|1P|E|1Q|F|G]]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|1R|8|@]|9|@]|A|$]]|$1|R|3|S|5|L|7|1S|8|@]|9|@]|A|$]]|$1|T|3|-4|5|6|7|1T|8|@]|9|@]|A|$]]|$1|U|3|-4|5|6|7|1U|8|@]|9|@]|A|$]]|$1|V|3|W|5|6|7|1V|8|@$D|1W|E|1X|F|G]]|9|@]|A|$]]|$1|X|3|-4|5|6|7|1Y|8|@]|9|@]|A|$]]|$1|Y|3|Z|5|L|7|1Z|8|@]|9|@]|A|$]]|$1|10|3|-4|5|6|7|20|8|@]|9|@]|A|$]]|$1|11|3|-4|5|6|7|21|8|@]|9|@]|A|$]]|$1|12|3|13|5|6|7|22|8|@$D|23|E|24|F|G]]|9|@]|A|$]]|$1|14|3|-4|5|6|7|25|8|@]|9|@]|A|$]]|$1|15|3|16|5|L|7|26|8|@]|9|@]|A|$]]|$1|17|3|-4|5|6|7|27|8|@]|9|@]|A|$]]|$1|18|3|-4|5|6|7|28|8|@]|9|@]|A|$]]|$1|19|3|1A|5|1B|7|29|8|@]|9|@]|A|$1C|1D]]|$1|1E|3|-4|5|6|7|2A|8|@]|9|@]|A|$]]]|1F|$]]

Quoting from Official <a href="http://developer.android.com/intl/in/reference/android/content/Intent.html" rel="nofollow">Guideline</a>

FLAG_ACTIVITY_CLEAR_TOP

<blockquote>
 If set, and the activity being launched is already running in the
 current task, then instead of launching a new instance of that
 activity, all of the other activities on top of it will be closed and
 this Intent will be delivered to the (now on top) old activity as a
 new Intent.
</blockquote>

FLAG_ACTIVITY_CLEAR_TASK

<blockquote>
 If set in an Intent passed to Context.startActivity(), this flag will
 cause any existing task that would be associated with the activity to
 be cleared before the activity is started. That is, the activity
 becomes the new root of an otherwise empty task, and any old
 activities are finished. This can only be used in conjunction with
 FLAG_ACTIVITY_NEW_TASK.
</blockquote>

FLAG_ACTIVITY_NO_HISTORY

<blockquote>
 If set, the new activity is not kept in the history stack. As soon as
 the user navigates away from it, the activity is finished. This may
 also be set with the noHistory attribute.
</blockquote>

FLAG_ACTIVITY_NEW_TASK

<blockquote>
 If set, this activity will become the start of a new task on this
 history stack.
</blockquote>

<pre><code>@Override
public void onBackPressed()
{

 Intent intCloseApp = new Intent(Intent.ACTION_MAIN);
 intCloseApp.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
 intCloseApp.addFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
 intCloseApp.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
 intCloseApp.addCategory(Intent.CATEGORY_HOME);
 intCloseApp.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
 startActivity(intCloseApp);
 }
</code></pre>

blocks|key|6008496|text|public+void+onBackPressed()+{
+System.exit(1);
+++return;
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|6008497|残酷的方式|unstyled|6008498|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>public void onBackPressed() {
 System.exit(1);
 return;
}
</code></pre>

the Brutal way

I want to go on home screen when I press device's back button.I am using this code..

<pre><code>public void onBackPressed() {
 this.finish();
 return;
}
</code></pre>

How can I close my application on back pressed in android

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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当我按下设备的背部按钮时，我想进入主屏幕。我正在使用这个代码。public void onBackPressed() {   this.finish();   return;}

问我如何在android中关闭我的应用程序
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问我如何在android中关闭我的应用程序EN