blocks|key|231998|text|用getActivity()替换context。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|231999|ApplicationContext不应用于创建对话框等任务。当您在片段中时，只需调用片段getActivity()方法即可获得活动上下文。|232000|entityMap^0|1|D|G|7|0|0|I|19|D|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|I|$]]

Replace <code>context</code> with <code>getActivity()</code>. 

The <code>ApplicationContext</code> should not be used for tasks such as creating Dialogs. As you are in a fragment you can instead get the Activity-Context simply by calling the Fragments <code>getActivity()</code> method.

blocks|key|3104337|text|有关此问题的更多信息(片段中的AlertDialog，在事件内部进行管理)：|type|unstyled|depth|inlineStyleRanges|offset|length|style|BOLD|entityRanges|data|3104338|如果在onClick(View+v)或onLongClick(View+v)等事件中调用AlertDialog，则可以使用|3104339|public+boolean+onClick(View+v)+{
++++...
++++AlertDialog.Builder+alertBuilder+=+new+AlertDialog.Builder(v.getContext());
++++...
}|code-block|syntax|javascript|3104340|entityMap^0|0|12|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|R|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|S|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|N|$]]

More Information about this question (AlertDialog in a fragment, managed inside an event):

If you call AlertDialog within an event like onClick(View v) or onLongClick(View v) you can use

<pre><code>public boolean onClick(View v) {
 ...
 AlertDialog.Builder alertBuilder = new AlertDialog.Builder(v.getContext());
 ...
}
</code></pre>

blocks|key|230997|text|尝试使用DialogFragment，当您使用片段时，DialogFragment更好|type|unstyled|depth|inlineStyleRanges|entityRanges|data|230998|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Try to use DialogFragment, DialogFragment is better when you use Fragments

blocks|key|3104401|text|我在尝试从片段创建AlertDialog时也遇到过类似的问题。由此产生了一个NullPointerException。最初，我这样做了：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3104402|AlertDialog+alertDialog+=+new+AlertDialog.Builder(getActivity()).create();|code-block|syntax|javascript|3104403|当稍后在代码中调用alertDialog.show()时，特别会发生NullPointerException。但是在文档中搜索AlertDialog.Builder()之后，似乎还有另一种方法可以将其初始化为[AlertDialog.Builder+Doc]，即包含一个主题/resId，如下所示：|offset|length|style|CODE|3104404|AlertDialog+alertDialog+=+new+AlertDialog.Builder(getActivity(),+R.style.Theme_AppCompat_Dialog_Alert).create();|3104405|这解决了手头的NullPointerException问题。希望这对你也有帮助！|3104406|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.android.com/reference/android/app/AlertDialog.Builder.html^0|0|0|9|I|Y|K|1R|L|2W|P|0|0|0|7|K|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|10|8|@$I|11|J|12|K|L]|$I|13|J|14|K|L]|$I|15|J|16|K|L]]|9|@$I|17|J|18|1|19]]|A|$]]|$1|M|3|N|5|D|7|1A|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|1B|8|@$I|1C|J|1D|K|L]]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|1E|8|@]|9|@]|A|$]]]|R|$S|$5|T|U|V|A|$W|X]]]]

I have had similar issues whereby I was trying to create an AlertDialog from a Fragment. A NullPointerException arose from it. Initially I did as follows:

<pre class="lang-java prettyprint-override"><code>AlertDialog alertDialog = new AlertDialog.Builder(getActivity()).create();
</code></pre>

The <code>NullPointerException</code> occurred specifically when calling <code>alertDialog.show()</code> later on in the code.
But after searching the documentation for <code>AlertDialog.Builder()</code>, there seemed to be another way to initialize it <a href="https://developer.android.com/reference/android/app/AlertDialog.Builder.html" rel="nofollow noreferrer">[AlertDialog.Builder Doc]</a>, which is to include a theme/resId as shown below:

<pre class="lang-java prettyprint-override"><code>AlertDialog alertDialog = new AlertDialog.Builder(getActivity(), R.style.Theme_AppCompat_Dialog_Alert).create();
</code></pre>

This resolved the <code>NullPointerException</code> at hand. Hope this helps you as well!

blocks|key|233494|text|我在listView内部的适配器中使用了它，因此我不能使用getActivity()。为了让它工作，我在片段中适配器的实例化中使用了getActivity()作为上下文：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|233495|this.adapter+=+new+myAdapter(getActivity(),+factory);|code-block|syntax|javascript|233496|后来在另一个类(适配器的类)中，我能够使用getContext()，并且它起作用了。|233497|entityMap^0|T|D|1U|D|0|0|L|C|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@]|E|$]]|$1|M|3|-4|5|6|7|X|8|@]|D|@]|E|$]]]|N|$]]

I used it in an adapter inside a listView, therefore I couldn't use <code>getActivity()</code>. In order to make it work I used <code>getActivity()</code> for the context in the instantiation of the adapter in the fragment:

<pre><code>this.adapter = new myAdapter(getActivity(), factory);
</code></pre>

Later in the other class (the adapter's class) I was able to use <code>getContext()</code>and it worked.

blocks|key|3104432|text|新生成器=+AlertDialog.Builder+AlertDialog.Builder(getActivity())；|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3104433|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());

blocks|key|3104342|text|+++++++++++++++++++++++AlertDialog+alert=+null;
++++++++++++++++++++++++AlertDialog.Builder+build=+new+AlertDialog.Builder(getActivity());
++++++++++++++++++++++++build.setTitle("title");
++++++++++++++++++++++++build.setItems(stringarrayname,+new+DialogInterface.OnClickListener()+{

++++++++++++++++++++++++++++@Override
++++++++++++++++++++++++++++public+void+onClick(DialogInterface+dialog,+int+which)+{
++++++++++++++++++++++++++++++++//+TODO+Auto-generated+method+stub
++++++++++++++++++++++++++++//Toast.makeText(getActivity(),+"hi",+Toast.LENGTH_SHORT).show();+++

++++++++++++++++++++++++++++}
++++++++++++++++++++++++});
++++++++++++++++++++++++build.create().show();|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|3104343|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code> AlertDialog alert= null;
 AlertDialog.Builder build= new AlertDialog.Builder(getActivity());
 build.setTitle("title");
 build.setItems(stringarrayname, new DialogInterface.OnClickListener() {

 @Override
 public void onClick(DialogInterface dialog, int which) {
 // TODO Auto-generated method stub
 //Toast.makeText(getActivity(), "hi", Toast.LENGTH_SHORT).show(); 

 }
 });
 build.create().show();
</code></pre>

blocks|key|3104357|text|您可以尝试这样做或使用DialogFragment|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3104358|private+void+showAlert(final+int+position)+{
++++++++new+AlertDialog.Builder(getActivity().getApplicationContext())
++++++++++++++++.setTitle("Delete+entry")
++++++++++++++++.setMessage("Are+you+sure+you+want+to+delete+this+entry?")
++++++++++++++++.setPositiveButton(android.R.string.yes,+new+DialogInterface.OnClickListener()+{
++++++++++++++++++++public+void+onClick(DialogInterface+dialog,+int+which)+{
++++++++++++++++++++++//++deleteSuggestions(position);
++++++++++++++++++++}
++++++++++++++++})
++++++++++++++++.setNegativeButton(android.R.string.no,+new+DialogInterface.OnClickListener()+{
++++++++++++++++++++public+void+onClick(DialogInterface+dialog,+int+which)+{
++++++++++++++++++++++++//+do+nothing
++++++++++++++++++++}
++++++++++++++++})
++++++++++++++++.setIcon(android.R.drawable.ic_dialog_alert)
++++++++++++++++.show();
++++}|code-block|syntax|javascript|3104359|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 or use DialogFragment

<pre><code>private void showAlert(final int position) {
 new AlertDialog.Builder(getActivity().getApplicationContext())
 .setTitle("Delete entry")
 .setMessage("Are you sure you want to delete this entry?")
 .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
 public void onClick(DialogInterface dialog, int which) {
 // deleteSuggestions(position);
 }
 })
 .setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener() {
 public void onClick(DialogInterface dialog, int which) {
 // do nothing
 }
 })
 .setIcon(android.R.drawable.ic_dialog_alert)
 .show();
 }
</code></pre>

blocks|key|2890386|text|解决方案是用getActivity()替代|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2890387|AlertDialog.Builder+alert+=+new+AlertDialog.Builder(getActivity(),R.style.MaDialog);|code-block|syntax|javascript|2890388|entityMap^0|6|D|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

The solution is to replace by <code>getActivity()</code>

<pre><code>AlertDialog.Builder alert = new AlertDialog.Builder(getActivity(),R.style.MaDialog);
</code></pre>

I want to display an alert dialog in my app. I am using fragments. I tried the below code to do this:

<pre><code> AlertDialog ad = new AlertDialog.Builder(context)
 .create();
 ad.setCancelable(false);
 ad.setTitle(title);
 ad.setMessage(message);
 ad.setButton(context.getString(R.string.ok_text), new DialogInterface.OnClickListener() {

 public void onClick(DialogInterface dialog, int which) {
 dialog.dismiss();
 }
 });
ad.show();
</code></pre>

but it was crashing and the error in logcat was:

<blockquote>
 04-18 15:23:01.770: E/AndroidRuntime(9424): android.view.WindowManager$BadTokenException: Unable to add window -- token null is not for an application
</blockquote>

From internet I came to know that the crash is due to context issue. I had given context as

<pre><code>context = this.getActivity().getApplicationContext();
</code></pre>

I don't know what is the problem with this. Can anybody help me?

How to display AlertDialog in a Fragment?

我想在我的应用程序中显示一个警告对话框。我使用的是片段。我尝试了下面的代码来做这件事： AlertDialog ad = new AlertDialog.Builder(context)            .create();    ad.setCancelable(false);    ad.setTitle(title);    ad.setMessage(message);    ad.

问如何在片段中显示AlertDialog？
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问如何在片段中显示AlertDialog？EN

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问如何在片段中显示AlertDialog？
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