blocks|key|655299|text|我曾经做过这样的事情；|type|unstyled|depth|inlineStyleRanges|entityRanges|data|655300|EditText+usernameEditText+=+(EditText)+findViewById(R.id.editUsername);
sUsername+=+usernameEditText.getText().toString();
if+(sUsername.matches(""))+{
++++Toast.makeText(this,+"You+did+not+enter+a+username",+Toast.LENGTH_SHORT).show();
++++return;
}|code-block|syntax|javascript|655301|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|$]]

I did something like this once;

<pre><code>EditText usernameEditText = (EditText) findViewById(R.id.editUsername);
sUsername = usernameEditText.getText().toString();
if (sUsername.matches("")) {
 Toast.makeText(this, "You did not enter a username", Toast.LENGTH_SHORT).show();
 return;
}
</code></pre>

blocks|key|655933|text|要验证EditText，请使用EditText#setError方法来显示错误并检查空值或null值，使用内置的android类TextUtils.isEmpty(strVar)，如果strVar为空或长度为零，则返回true|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|655934|EditText+etUserName+=+(EditText)+findViewById(R.id.txtUsername);
String+strUserName+=+etUserName.getText().toString();

+if(TextUtils.isEmpty(strUserName))+{
++++etUserName.setError("Your+message");
++++return;
+}|code-block|syntax|javascript|655935|​|655936|📷|atomic|655937|655938|entityMap|0|LINK|mutability|MUTABLE|url|http://developer.android.com/reference/android/widget/TextView.html#setError%2528java.lang.CharSequence%2529|1|http://developer.android.com/reference/android/text/TextUtils.html#isEmpty%2528java.lang.CharSequence%2529|2|IMAGE|IMMUTABLE|imageUrl|https://ask.qcloudimg.com/http-save/yehe-900000/cd2bd710e5d2ec3863c30d48d6f3ef06.jpeg|imageAlt^0|F|H|0|1S|P|1|0|0|0|0|1|2|0|0^^$0|@$1|2|3|4|5|6|7|14|8|@]|9|@$A|15|B|16|1|17]|$A|18|B|19|1|1A]]|C|$]]|$1|D|3|E|5|F|7|1B|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|1C|8|@]|9|@]|C|$]]|$1|K|3|L|5|M|7|1D|8|@]|9|@$A|1E|B|1F|1|1G]]|C|$]]|$1|N|3|J|5|6|7|1H|8|@]|9|@]|C|$]]|$1|O|3|-4|5|6|7|1I|8|@]|9|@]|C|$]]]|P|$Q|$5|R|S|T|C|$U|V]]|W|$5|R|S|T|C|$U|X]]|Y|$5|Z|S|10|C|$11|12|13|-4]]]]

For validating EditText use <a href="http://developer.android.com/reference/android/widget/TextView.html#setError%28java.lang.CharSequence%29">EditText#setError</a> method for show error and for checking empty or null value use inbuilt android class <a href="http://developer.android.com/reference/android/text/TextUtils.html#isEmpty%28java.lang.CharSequence%29">TextUtils.isEmpty(strVar)</a> which return true if strVar is null or zero length 

<pre><code>EditText etUserName = (EditText) findViewById(R.id.txtUsername);
String strUserName = etUserName.getText().toString();

 if(TextUtils.isEmpty(strUserName)) {
 etUserName.setError("Your message");
 return;
 }
</code></pre>

<img src="https://i.stack.imgur.com/qdhpK.jpg" alt="Image taken from Google search">

blocks|key|872627|text|试试这个：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|872628|EditText+txtUserName+=+(EditText)+findViewById(R.id.txtUsername);
String+strUserName+=+usernameEditText.getText().toString();
if+(strUserName.trim().equals(""))+{
++++Toast.makeText(this,+"plz+enter+your+name+",+Toast.LENGTH_SHORT).show();
++++return;
}|code-block|syntax|javascript|872629|或者像这样使用TextUtils类：|offset|length|872630|if(TextUtils.isEmpty(strUserName))+{
++++Toast.makeText(this,+"plz+enter+your+name+",+Toast.LENGTH_SHORT).show();
++++return;
}|872631|entityMap|0|LINK|mutability|MUTABLE|url|http://developer.android.com/reference/android/text/TextUtils.html^0|0|0|7|9|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|W|8|@]|9|@$I|X|J|Y|1|Z]]|A|$]]|$1|K|3|L|5|D|7|10|8|@]|9|@]|A|$E|F]]|$1|M|3|-4|5|6|7|11|8|@]|9|@]|A|$]]]|N|$O|$5|P|Q|R|A|$S|T]]]]

try this : 

<pre><code>EditText txtUserName = (EditText) findViewById(R.id.txtUsername);
String strUserName = usernameEditText.getText().toString();
if (strUserName.trim().equals("")) {
 Toast.makeText(this, "plz enter your name ", Toast.LENGTH_SHORT).show();
 return;
}
</code></pre>

or use the <a href="http://developer.android.com/reference/android/text/TextUtils.html" rel="noreferrer">TextUtils</a> class like this : 

<pre><code>if(TextUtils.isEmpty(strUserName)) {
 Toast.makeText(this, "plz enter your name ", Toast.LENGTH_SHORT).show();
 return;
}
</code></pre>

blocks|key|655848|text|其他答案都是正确的，但要用一种简短的方法，比如|type|unstyled|depth|inlineStyleRanges|entityRanges|data|655849|if(editText.getText().toString().isEmpty())+{
+++++//+editText+is+empty
}+else+{
+++++//+editText+is+not+empty
}|code-block|syntax|javascript|655850|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|$]]

Other answers are correct but do it in a short way like

<pre><code>if(editText.getText().toString().isEmpty()) {
 // editText is empty
} else {
 // editText is not empty
}
</code></pre>

blocks|key|872749|text|您可以从EditText使用length()。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|872750|public+boolean+isEditTextEmpty(EditText+mInput){
+++return+mInput.length()+==+0;
}|code-block|syntax|javascript|872751|entityMap^0|4|8|E|8|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

You can use <code>length()</code> from <code>EditText</code>.

<pre><code>public boolean isEditTextEmpty(EditText mInput){
 return mInput.length() == 0;
}
</code></pre>

blocks|key|655561|text|我通常按照SBJ的建议去做，但情况正好相反。我只是发现，通过检查肯定的结果而不是双重否定，更容易理解我的代码。您可能会问如何检查EdiTexts是否为空，但您真正想知道的是它是否包含任何内容，而不是它是否不为空。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|655562|如下所示：|655563|private+boolean+hasContent(EditText+et)+{
++++//+Always+assume+false+until+proven+otherwise
++++boolean+bHasContent+=+false;+

++++if+(et.getText().toString().trim().length()+>+0)+{
++++++++//+Got+content
++++++++bHasContent+=+true;
++++}
++++return+bHasContent;
}|code-block|syntax|javascript|655564|作为SBJ，我更喜欢返回"has+no“(或false)作为默认值，以避免异常，因为我借用了content-check。这样，您将绝对确定true已被您的检查“批准”。|style|CODE|655565|我也认为调用它的if看起来更干净一些：|655566|if+(hasContent(myEditText))+{
//+Act+upon+content
}+else+{
//+Got+no+content!
}|655567|它在很大程度上依赖于偏好，但我发现这更容易阅读。:)|655568|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/6290970/2046119|1^0|5|3|0|0|0|0|M|5|1X|4|2|3|1|0|8|2|0|0|0^^$0|@$1|2|3|4|5|6|7|13|8|@]|9|@$A|14|B|15|1|16]]|C|$]]|$1|D|3|E|5|6|7|17|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|18|8|@]|9|@]|C|$I|J]]|$1|K|3|L|5|6|7|19|8|@$A|1A|B|1B|M|N]|$A|1C|B|1D|M|N]]|9|@$A|1E|B|1F|1|1G]]|C|$]]|$1|O|3|P|5|6|7|1H|8|@$A|1I|B|1J|M|N]]|9|@]|C|$]]|$1|Q|3|R|5|H|7|1K|8|@]|9|@]|C|$I|J]]|$1|S|3|T|5|6|7|1L|8|@]|9|@]|C|$]]|$1|U|3|-4|5|6|7|1M|8|@]|9|@]|C|$]]]|V|$W|$5|X|Y|Z|C|$10|11]]|12|$5|X|Y|Z|C|$10|11]]]]

I usually do what <a href="https://stackoverflow.com/a/6290970/2046119">SBJ</a> proposes, but the other way around. I simply find it easier to understand my code by checking for positive results instead of double negatives. 
You might be asking for how to check for empty EdiTexts, but what you really want to know is if it has any content and not that it is not empty. 

Like so:

<pre><code>private boolean hasContent(EditText et) {
 // Always assume false until proven otherwise
 boolean bHasContent = false; 

 if (et.getText().toString().trim().length() &gt; 0) {
 // Got content
 bHasContent = true;
 }
 return bHasContent;
}
</code></pre>

As <a href="https://stackoverflow.com/a/6290970/2046119">SBJ</a> I prefer to return "has no content" (or <code>false</code>) as default to avoid exceptions because I borked my content-check. That way you will be absolutely certain that a <code>true</code> has been "approved" by your checks.

I also think the <code>if</code> calling it looks a bit cleaner as well:

<pre><code>if (hasContent(myEditText)) {
// Act upon content
} else {
// Got no content!
}
</code></pre>

It is very much dependent on preference, but i find this easier to read. :)

blocks|key|655725|text|如果EditText为空，为什么不直接禁用该按钮呢？我觉得这看起来更专业：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|655726|++++++++final+EditText+txtFrecuencia+=+(EditText)+findViewById(R.id.txtFrecuencia);++
++++++++final+ToggleButton+toggle+=+(ToggleButton)+findViewById(R.id.toggleStartStop);
++++++++txtFrecuencia.addTextChangedListener(new+TextWatcher()+{
++++++++@Override
++++++++public+void+afterTextChanged(Editable+s)+{
++++++++++++toggle.setEnabled(txtFrecuencia.length()+>+0);
++++++++}

++++++++@Override
++++++++public+void+beforeTextChanged(CharSequence+s,+int+start,+int+count,
++++++++++++++++int+after)+{
++++++++}

++++++++@Override
++++++++public+void+onTextChanged(CharSequence+s,+int+start,+int+before,
++++++++++++++++int+count)+{

++++++++}
+++++++});|code-block|syntax|javascript|655727|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|$]]

Why not just disable the button if EditText is empty? IMHO This looks more professional:

<pre><code> final EditText txtFrecuencia = (EditText) findViewById(R.id.txtFrecuencia); 
 final ToggleButton toggle = (ToggleButton) findViewById(R.id.toggleStartStop);
 txtFrecuencia.addTextChangedListener(new TextWatcher() {
 @Override
 public void afterTextChanged(Editable s) {
 toggle.setEnabled(txtFrecuencia.length() &gt; 0);
 }

 @Override
 public void beforeTextChanged(CharSequence s, int start, int count,
 int after) {
 }

 @Override
 public void onTextChanged(CharSequence s, int start, int before,
 int count) {

 }
 });
</code></pre>

blocks|key|655812|text|我使用这个方法，它使用trim()来避免空格：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|655813|EditText+myEditText+=+(EditText)+findViewById(R.id.editUsername);
if+("".equals(myEditText.getText().toString().trim())+{
++++Toast.makeText(this,+"You+did+not+enter+a+value!",+Toast.LENGTH_LONG).show();
++++return;
}|code-block|syntax|javascript|655814|举个例子，如果你有几个EditText|655815|if+(("".equals(edtUser.getText().toString().trim())+%7C%7C+"".equals(edtPassword.getText().toString().trim()))){
++++++++Toast.makeText(this,+"a+value+is+missing!",+Toast.LENGTH_LONG).show();
++++++++return;
}|655816|entityMap^0|B|6|0|0|0|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]]|$1|K|3|L|5|6|7|U|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|P|$]]

I use this method, that uses <code>trim()</code> to avoid blank spaces :

<pre><code>EditText myEditText = (EditText) findViewById(R.id.editUsername);
if ("".equals(myEditText.getText().toString().trim()) {
 Toast.makeText(this, "You did not enter a value!", Toast.LENGTH_LONG).show();
 return;
}
</code></pre>

an example if you have several EditText´s

<pre><code>if (("".equals(edtUser.getText().toString().trim()) || "".equals(edtPassword.getText().toString().trim()))){
 Toast.makeText(this, "a value is missing!", Toast.LENGTH_LONG).show();
 return;
}
</code></pre>

blocks|key|656123|text|if(TextUtils.isEmpty(textA.getText())){
++++++++++++showToast(it's+Null");
++++++++}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|656124|你可以像我的例子一样使用TextUtils.isEmpty！祝好运|unstyled|656125|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>if(TextUtils.isEmpty(textA.getText())){
 showToast(it's Null");
 }
</code></pre>

you can use TextUtils.isEmpty like my Example ! 
Good luck

blocks|key|655600|text|private+boolean+hasContent(EditText+et)+{
+++++++return+(et.getText().toString().trim().length()+>+0);
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|655601|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>private boolean hasContent(EditText et) {
 return (et.getText().toString().trim().length() &gt; 0);
}
</code></pre>

blocks|key|873132|text|我使用TextUtils实现了以下目的：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|873133|if+(TextUtils.isEmpty(UsernameInfo.getText()))+{
++++validationError+=+true;
++++validationErrorMessage.append(getResources().getString(R.string.error_blank_username));
}|code-block|syntax|javascript|873134|entityMap^0|3|9|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|$]]

I used <code>TextUtils</code> for this:

<pre><code>if (TextUtils.isEmpty(UsernameInfo.getText())) {
 validationError = true;
 validationErrorMessage.append(getResources().getString(R.string.error_blank_username));
}
</code></pre>

blocks|key|655763|text|您还可以在一个If条件中检查所有EditText字符串，如下所示|type|unstyled|depth|inlineStyleRanges|entityRanges|data|655764|if+(mString.matches("")+%7C%7C+fString.matches("")+%7C%7C+gender==null+%7C%7C+docString.matches("")+%7C%7C+dString.matches(""))+{
++++++++++++++++Toast.makeText(WriteActivity.this,"Data+Incomplete",+Toast.LENGTH_SHORT).show();
++++++++++++}|code-block|syntax|javascript|655765|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 also check all the EditText Strings in one If condition: like this

<pre><code>if (mString.matches("") || fString.matches("") || gender==null || docString.matches("") || dString.matches("")) {
 Toast.makeText(WriteActivity.this,"Data Incomplete", Toast.LENGTH_SHORT).show();
 }
</code></pre>

blocks|key|873262|text|我想做一些类似的事情。但是从编辑文本中获取文本值并将其与(str=="")进行比较对我来说是行不通的。所以更好的选择是：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|873263|EditText+eText+=+(EditText)+findViewById(R.id.etext);

if+(etext.getText().length()+==+0)
{//do+what+you+want+}|code-block|syntax|javascript|873264|就像一个护身符。|873265|entityMap^0|S|9|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|S|8|@]|D|@]|E|$]]|$1|M|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|N|$]]

I wanted to do something similar. But getting the text value from edit text and comparing it like <code>(str=="")</code> wasn't working for me. So better option was:

<pre><code>EditText eText = (EditText) findViewById(R.id.etext);

if (etext.getText().length() == 0)
{//do what you want }
</code></pre>

Worked like a charm.

blocks|key|656090|text|使用If+ELSE+If条件来尝试这一点。您可以轻松地验证editText字段。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|656091|+if(TextUtils.isEmpty(username))+{
++++++++++++++++userNameView.setError("User+Name+Is+Essential");
++++++++++++++++return;
+++++++++}+else++if(TextUtils.isEmpty(phone))+{
++++++++++++++++phoneView.setError("Please+Enter+Your+Phone+Number");
++++++++++++++++return;
++++++++++++}|code-block|syntax|javascript|656092|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|$]]

Try this out with using If ELSE If conditions. You can validate your editText fields easily.

<pre><code> if(TextUtils.isEmpty(username)) {
 userNameView.setError("User Name Is Essential");
 return;
 } else if(TextUtils.isEmpty(phone)) {
 phoneView.setError("Please Enter Your Phone Number");
 return;
 }
</code></pre>

blocks|key|656132|text|您可以为每个编辑文本调用此函数：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|656133|public+boolean+isEmpty(EditText+editText)+{
++++boolean+isEmptyResult+=+false;
++++if+(editText.getText().length()+==+0)+{
++++++++isEmptyResult+=+true;
++++}
++++return+isEmptyResult;
}|code-block|syntax|javascript|656134|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 could call this function for each of the edit texts:

<pre><code>public boolean isEmpty(EditText editText) {
 boolean isEmptyResult = false;
 if (editText.getText().length() == 0) {
 isEmptyResult = true;
 }
 return isEmptyResult;
}
</code></pre>

blocks|key|872933|text|EditText+txtUserID+=+(EditText)+findViewById(R.id.txtUserID);

String+UserID+=+txtUserID.getText().toString();

if+(UserID.equals(""))+

{
++++Log.d("value","null");
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|872934|您将在LogCat中看到此消息...|unstyled|872935|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>EditText txtUserID = (EditText) findViewById(R.id.txtUserID);

String UserID = txtUserID.getText().toString();

if (UserID.equals("")) 

{
 Log.d("value","null");
}
</code></pre>

You will see the message in LogCat....

blocks|key|655995|text|对单行代码使用TextUtils.isEmpty("Text+here");|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|655996|entityMap^0|7|V|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

use <code>TextUtils.isEmpty("Text here");</code> for single line code

blocks|key|656343|text|使用这段简短的代码，您可以删除字符串开头和结尾的空格。如果字符串为"“，则返回消息"error”，否则将返回一个字符串|type|unstyled|depth|inlineStyleRanges|entityRanges|data|656344|EditText+user+=+findViewById(R.id.user);+
userString+=+user.getText().toString().trim();+
if+(userString.matches(""))+{
++++Toast.makeText(this,+"Error",+Toast.LENGTH_SHORT).show();
++++return;+
}else{
+++++Toast.makeText(this,+"Ok",+Toast.LENGTH_SHORT).show();
}|code-block|syntax|javascript|656345|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|$]]

with this short code you can delete empty space at start and end of the string. If the string is "" return the message "error" else you ave a string

<pre><code>EditText user = findViewById(R.id.user); 
userString = user.getText().toString().trim(); 
if (userString.matches("")) {
 Toast.makeText(this, "Error", Toast.LENGTH_SHORT).show();
 return; 
}else{
 Toast.makeText(this, "Ok", Toast.LENGTH_SHORT).show();
}
</code></pre>

blocks|key|872706|text|EditText+edt=(EditText)findViewById(R.id.Edt);

String+data=edt.getText().toString();

if(data==""+%7C%7C+data==null){

+Log.e("edit+text+is+null?","yes");

}

else+{

+Log.e("edit+text+is+null?","no");

}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|872707|对所有五个编辑文本执行以下操作|unstyled|872708|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>EditText edt=(EditText)findViewById(R.id.Edt);

String data=edt.getText().toString();

if(data=="" || data==null){

 Log.e("edit text is null?","yes");

}

else {

 Log.e("edit text is null?","no");

}
</code></pre>

do like this for all five edit text

blocks|key|655873|text|要editText+is+empty，请尝试另一种简单的方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|655874|String+star+=+editText.getText().toString();

if+(star.equalsIgnoreCase(""))+{
++Toast.makeText(getApplicationContext(),+"Please+Set+start+no",+Toast.LENGTH_LONG).show();
}|code-block|syntax|javascript|655875|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|$]]

To editText is empty try another this simple way :

<pre><code>String star = editText.getText().toString();

if (star.equalsIgnoreCase("")) {
 Toast.makeText(getApplicationContext(), "Please Set start no", Toast.LENGTH_LONG).show();
}
</code></pre>

blocks|key|655985|text|你可以使用setOnFocusChangeListener，它会在焦点改变时进行检查|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|655986|++++++++txt_membername.setOnFocusChangeListener(new+OnFocusChangeListener()+{

++++++++@Override
++++++++public+void+onFocusChange(View+arg0,+boolean+arg1)+{
++++++++++++if+(arg1)+{
++++++++++++++++//do+something
++++++++++++}+else+{
++++++++++++++++if+(txt_membername.getText().toString().length()+==+0)+{
++++++++++++++++++++txt_membername
++++++++++++++++++++++++++++.setError("Member+name+is+not+empty,+Plz!");
++++++++++++++++}
++++++++++++}
++++++++}
++++});|code-block|syntax|javascript|655987|entityMap^0|5|O|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|$]]

You can use <code>setOnFocusChangeListener</code> , it will check when focus change 

<pre><code> txt_membername.setOnFocusChangeListener(new OnFocusChangeListener() {

 @Override
 public void onFocusChange(View arg0, boolean arg1) {
 if (arg1) {
 //do something
 } else {
 if (txt_membername.getText().toString().length() == 0) {
 txt_membername
 .setError("Member name is not empty, Plz!");
 }
 }
 }
 });
</code></pre>

blocks|key|873319|text|if+(+(usernameEditText.getText()%2B"").equals("")+)+{+
++++//+Really+just+another+way
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|873320|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>if ( (usernameEditText.getText()+"").equals("") ) { 
 // Really just another way
}
</code></pre>

blocks|key|656054|text|我更喜欢使用ButterKnife列表绑定，然后在列表上应用操作。例如，对于EditTexts，我在一个实用程序类(在本例中是ButterKnifeActions)中定义了以下自定义操作|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|656055|public+static+<V+extends+View>+boolean+checkAll(List<V>+views,+ButterKnifeActions.Check<V>+checker)+{
++++boolean+hasProperty+=+true;
++++for+(int+i+=+0;+i+<+views.size();+i%2B%2B)+{
++++++++hasProperty+=+checker.checkViewProperty(views.get(i),+i)+&&+hasProperty;
++++}
++++return+hasProperty;
}

public+static+<V+extends+View>+boolean+checkAny(List<V>+views,+ButterKnifeActions.Check<V>+checker)+{
++++boolean+hasProperty+=+false;
++++for+(int+i+=+0;+i+<+views.size();+i%2B%2B)+{
++++++++hasProperty+=+checker.checkViewProperty(views.get(i),+i)+%7C%7C+hasProperty;
++++}
++++return+hasProperty;
}

public+interface+Check<V+extends+View>+{
++++boolean+checkViewProperty(V+view,+int+index);
}

public+static+final+ButterKnifeActions.Check<EditText>+EMPTY+=+new+Check<EditText>()+{
++++@Override
++++public+boolean+checkViewProperty(EditText+view,+int+index)+{
++++++++return+TextUtils.isEmpty(view.getText());
++++}
};|code-block|syntax|javascript|656056|在视图代码中，我将EditTexts绑定到列表，并在需要检查视图时应用操作。|656057|@Bind({R.id.edit1,+R.id.edit2,+R.id.edit3,+R.id.edit4,+R.id.edit5})+List<EditView>+edits;
...
if+(ButterKnifeActions.checkAny(edits,+ButterKnifeActions.EMPTY))+{
++++Toast.makeText(getContext(),+"Please+fill+in+all+fields",+Toast.LENGTH_SHORT).show();
}|656058|当然，这种模式可以扩展到检查任意数量的视图上的任何属性。唯一的缺点，如果你可以这么说，就是视图的冗余。这意味着，要使用这些EditTexts，您还必须将它们绑定到单个变量，以便可以按名称引用它们，或者必须按列表中的位置(edits.get(0)等)引用它们。就我个人而言，我只是将它们绑定了两次，一次绑定到单个变量，一次绑定到列表，并使用任何合适的。|656059|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/JakeWharton/butterknife^0|1R|I|6|B|0|0|0|0|0|32|C|0^^$0|@$1|2|3|4|5|6|7|Y|8|@$9|Z|A|10|B|C]]|D|@$9|11|A|12|1|13]]|E|$]]|$1|F|3|G|5|H|7|14|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|15|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|16|8|@]|D|@]|E|$I|J]]|$1|O|3|P|5|6|7|17|8|@$9|18|A|19|B|C]]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|1A|8|@]|D|@]|E|$]]]|R|$S|$5|T|U|V|E|$W|X]]]]

I prefer using <a href="https://github.com/JakeWharton/butterknife" rel="nofollow">ButterKnife</a> list binding and then applying actions on the list. For example, with the case of EditTexts, I have the following custom actions defined in a utility class (in this case <code>ButterKnifeActions</code>)

<pre><code>public static &lt;V extends View&gt; boolean checkAll(List&lt;V&gt; views, ButterKnifeActions.Check&lt;V&gt; checker) {
 boolean hasProperty = true;
 for (int i = 0; i &lt; views.size(); i++) {
 hasProperty = checker.checkViewProperty(views.get(i), i) &amp;&amp; hasProperty;
 }
 return hasProperty;
}

public static &lt;V extends View&gt; boolean checkAny(List&lt;V&gt; views, ButterKnifeActions.Check&lt;V&gt; checker) {
 boolean hasProperty = false;
 for (int i = 0; i &lt; views.size(); i++) {
 hasProperty = checker.checkViewProperty(views.get(i), i) || hasProperty;
 }
 return hasProperty;
}

public interface Check&lt;V extends View&gt; {
 boolean checkViewProperty(V view, int index);
}

public static final ButterKnifeActions.Check&lt;EditText&gt; EMPTY = new Check&lt;EditText&gt;() {
 @Override
 public boolean checkViewProperty(EditText view, int index) {
 return TextUtils.isEmpty(view.getText());
 }
};
</code></pre>

And in the view code, I bind the EditTexts to a list and apply the actions when I need to check the views.

<pre><code>@Bind({R.id.edit1, R.id.edit2, R.id.edit3, R.id.edit4, R.id.edit5}) List&lt;EditView&gt; edits;
...
if (ButterKnifeActions.checkAny(edits, ButterKnifeActions.EMPTY)) {
 Toast.makeText(getContext(), "Please fill in all fields", Toast.LENGTH_SHORT).show();
}
</code></pre>

And of course this pattern is extendable to checking any property on any number of views. The only downside, if you can call it that, is the redundancy of views. Meaning, to use those EditTexts, you would have to bind them to single variables as well so that you can reference them by name or you would have to reference them by position in the list (<code>edits.get(0)</code>, etc.). Personally, I just bind each of them twice, once to a single variable and once to a the list and use whichever is appropriate.

blocks|key|656182|text|试试这个:它的Kotlin版本|type|unstyled|depth|inlineStyleRanges|entityRanges|data|656183|//button+from+xml
button.setOnClickListener{+++++++++++++++++++++++++++++++++++++++++
++++val+new=addText.text.toString()//addText+is+an+EditText
++++if(new=isNotEmpty())
++++{
+++++++++//do+something
++++}
++++else{
++++++++new.setError("Enter+some+msg")
++++++++//or
++++++++Toast.makeText(applicationContext,+"Enter+some+message+",+Toast.LENGTH_SHORT).show()
++++}
}|code-block|syntax|javascript|656184|谢谢|656185|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|$]]

Try this out:
its in Kotlin 

<pre><code>//button from xml
button.setOnClickListener{ 
 val new=addText.text.toString()//addText is an EditText
 if(new=isNotEmpty())
 {
 //do something
 }
 else{
 new.setError("Enter some msg")
 //or
 Toast.makeText(applicationContext, "Enter some message ", Toast.LENGTH_SHORT).show()
 }
}
</code></pre>

Thank you

blocks|key|873524|text|此函数适用于我|type|unstyled|depth|inlineStyleRanges|entityRanges|data|873525|private+void+checkForm()+{
++++EditText[]+allFields+=+{
++++++++field1_txt,
++++++++field2_txt,
++++++++field3_txt,
++++++++field4_txt
++++};
++++
++++List+<+EditText+>+ErrorFields+=+new+ArrayList+<+EditText+>+();+

++++for+(EditText+edit:+allFields)+{
++++++++if+(TextUtils.isEmpty(edit.getText()))+{

++++++++++++//+EditText+was+empty
++++++++++++ErrorFields.add(edit);+//add+empty+Edittext+only+in+this+ArayList
++++++++++++
++++++++++++for+(int+i+=+0;+i+<+ErrorFields.size();+i%2B%2B)+{
++++++++++++++++EditText+currentField+=+ErrorFields.get(i);
++++++++++++++++currentField.setError("this+field+required");
++++++++++++++++currentField.requestFocus();
++++++++++++}
++++++++}
++++}
}|code-block|syntax|javascript|873526|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|$]]

This function work for me
<pre><code>private void checkForm() {
 EditText[] allFields = {
 field1_txt,
 field2_txt,
 field3_txt,
 field4_txt
 };
 
 List &lt; EditText &gt; ErrorFields = new ArrayList &lt; EditText &gt; (); 

 for (EditText edit: allFields) {
 if (TextUtils.isEmpty(edit.getText())) {

 // EditText was empty
 ErrorFields.add(edit); //add empty Edittext only in this ArayList
 
 for (int i = 0; i &lt; ErrorFields.size(); i++) {
 EditText currentField = ErrorFields.get(i);
 currentField.setError(&quot;this field required&quot;);
 currentField.requestFocus();
 }
 }
 }
}
</code></pre>

blocks|key|656301|text|下面这些对我来说都适用于一句话：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|656302|if(searchText.getText().toString().equals(""))+
++++Log.d("MY_LOG",+"Empty");|code-block|syntax|javascript|656303|首先，我从EditText中检索文本，然后将其转换为字符串，最后使用.equals方法将其与""进行比较。|offset|length|style|CODE|656304|entityMap^0|0|0|5|8|Y|7|1A|2|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]|$I|T|J|U|K|L]|$I|V|J|W|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|X|8|@]|9|@]|A|$]]]|N|$]]

The following works for me all in one statement:

<pre><code>if(searchText.getText().toString().equals("")) 
 Log.d("MY_LOG", "Empty");
</code></pre>

First I retrieve a text from the <code>EditText</code> and then convert it to a string and finally comparing it with <code>""</code> using <code>.equals</code> method.

I have 5 <code>EditTexts</code> in android. I would like to know if I could check if all 5 <code>EditTexts</code> are null. Is there any way to do this??

How do I check if my EditText fields are empty?

Kotlin

我在安卓系统里有5个EditTexts。我想知道我是否可以检查是否所有5个EditTexts都为空。有没有办法做到这一点？？

问如何检查我的EditText字段是否为空？
EN

回答 26

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问如何检查我的EditText字段是否为空？EN

回答 26

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问如何检查我的EditText字段是否为空？
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