Program Crashes in App, Need Loop Fixed [duplicate] - java

I have an EditText box where the user can enter input. I need to display the input text in a TextView (which is placed below the EditText) while the user inputting the text.
Example:
If the user is entering any characters in EditText box, I need to display the same characters in TextView. In the same way, If the user deletes any character from EditText, I need to remove the same character from TextView. (Ultimately, I want to change TextView's text on change of EditText's text). I hope my requirement is clear now. How can I achieve this? Please guide me.

Add TextWatcher to your Edittext. in afterTextChanged() do your operation.
http://developer.android.com/reference/android/text/TextWatcher.html
TextWatcher inputTextWatcher = new TextWatcher() {
public void afterTextChanged(Editable s) {
textview.setText(s.toString());
}
public void beforeTextChanged(CharSequence s, int start, int count, int after){
}
public void onTextChanged(CharSequence s, int start, int before, int count) {
}
};
editText.addTextChangedListener(inputTextWatcher);

edtText.addTextChangedListener(new TextWatcher() {
#Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
// TODO Auto-generated method stub
}
#Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
// TODO Auto-generated method stub
}
#Override
public void afterTextChanged(Editable s) {
// TODO Auto-generated method stub
if (!edtText.getText().toString().equalsIgnoreCase("")){
// here textview.setText(edtText.getText());
}
}
});
}

You should overwrite this method :
editText.addTextChangedListener(new TextWatcher() {
#Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
}
#Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
#Override
public void afterTextChanged(Editable s) {
if(editText.getText().length() >= 0) {
textView.setText(editText.getText().toString())
}
}
});

The solution is to add TextWatcher to the EditText by using addTextChangedListener() function. In TextWatcher you'll need to write transformation / validation logic inside one of 3 functions afterTextChanged(), beforeTextChanged(), onTextChanged() depending on when you want to perform those actions.
Using Kotlin you would do something like that:
editText.addTextChangedListener(object : android.text.TextWatcher {
override fun afterTextChanged(s: Editable?) {
}
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {
}
override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
s?.let { textView.text = s.toString() }
}
})

Related

when setText on editText TextWatcher.onTextChanged not called

Whenever EditText string is changed, onTextChanged is called.
Now when I start a new Activity and send data through Bundle, onTextChanged is not called.
if( getIntent().getExtras() != null) {
Bundle b = getIntent().getExtras();
int value = -1;
if(b != null)
value = b.getInt("key");
edit1.setText("Mywords:");
}
How can I call it ?
So here's the modified version of your code. The idea is to set the text in the EditText after you add a TextWatcher on it.
if( getIntent().getExtras() != null) {
Bundle b = getIntent().getExtras();
int value = -1;
if(b != null)
value = b.getInt("key");
// Add the TextWatcher here
edit1.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
// Toast.makeText(MainActivity.this, "before text changed", Toast.LENGTH_LONG).show();
}
#Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
// Toast.makeText(MainActivity.this, "on text changed", Toast.LENGTH_LONG).show();
}
#Override
public void afterTextChanged(Editable s) {
// Toast.makeText(MainActivity.this, "after text changed", Toast.LENGTH_LONG).show();
}
});
// Now the set the value in your EditText
edit1.setText("Mywords:");
}
Make sure you are subscribing with TextWatcher before setText called.
For some reason, the method addTextChangedListener is not called for me.
However the method doBeforeTextChanged, doOnTextChanged and doAfterTextChanged worked perfectly :
amountTextField.doBeforeTextChanged { text, start, count, after ->
Log.d(TAG, "beforeTextChange.") // OK, called
}
amountTextField.doOnTextChanged { text, start, before, count ->
Log.d(TAG, "onTextChanged.") // OK, called
}
amountTextField.doAfterTextChanged {
Log.d(TAG, "afterTextChanged.") // OK, called
}
amountTextField.addTextChangedListener {
object: TextWatcher {
override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
Log.d(TAG, "beforeTextChange.") // NOK, not called
}
override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
Log.d(TAG, "onTextChanged.") // NOK, not called
}
override fun afterTextChanged(p0: Editable?) {
Log.d(TAG, "onTextChanged.") // NOK, not called
}
} }
By the way, the result was always the same : whether I set any text to my EidtText or not, whether after or before I set any text.
Try the following:
edit1.addTextChangedListener(new TextWatcher() {
public void afterTextChanged(Editable s) {}
public void beforeTextChanged(CharSequence s, int start,
int count, int after) {
}
public void onTextChanged(CharSequence s, int start,
int before, int count) {
}
});
Reference: android on Text Change Listener

EditText.setError for a not focusable view

I want to show error for a not focusable EditText. But I can not see the message. Only red icon. Somebody says I need to request the focus manually. This is how I did:
mStartDateEditText.requestFocus();
mStartDateEditText.setError("Message");
But it doesn't work.
In my case is similar i used a TextWatcher , e.g.:
username.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
#Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
}
#Override
public void afterTextChanged(Editable s) {
if(s.length()==0){
username.requestFocus();
username.setError("Please enter your username.");
}else{
username.setError(null);
}
}
});

dynamically change the length of String inside the EditText field in Android

I am using an EditText field in my application.
EditText is for entering the ddns input:
e.g www.example.com/xxxx
I want to restrict the length of the ddns id to 30 characters after "/" character.
i.e after "/" character, what follows must be of maximum 30 characters
I want to do it dynamically and restrict user to not type more than 30 characters.
How can i do it.
You can try the below way to restrict the user to enter less than 30 character.
tf.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
//processing part
}
});
A very fast and ugly answer would look something like this:
yourEditText.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
#Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
if(s.toString().contains('/') {
if(s.toString().split('/')[1].length() == 30) {
//By only working with the EditText:
InputMethodManager imm = (InputMethodManager)
getSystemService(INPUT_METHOD_SERVICE);
imm.hideSoftInputFromWindow(getCurrentFocus().getWindowToken(), 0);
yourEditText.setFocusable(false);
yoruEditText.setEnabled(false);
}
}
}
#Override
public void afterTextChanged(Editable s) {
}});
//What i think is the best implementation, adding a TextView sitting on top of
//EditText with visibility set to GONE
yourEditText.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
#Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
if(s.toString().contains('/') {
if(s.toString().split('/')[1].length() == 30) {
//By working with EditText and a TextView
yourEditText.setVisibility(View.GONE);
yourTextView.setVisibility(View.VISIBLE);
yourTextView.setText(s);
}
}
}
#Override
public void afterTextChanged(Editable s) {
}});
In any case you want to add a textWatcher to your editText and change it accordingly.

How does TextWatcher.onTextChanged() handle predictive text?

How are start, before, and count values called when we choose a prediction, for ex Do->Doc->Document. It sometimes deletes the word and inserts again with 2 calls, sometimes in the same call.
Please advice.
Check this link & take reference. of below code.
et1.addTextChangedListener(new TextWatcher() {
#Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
/*Whenever You will Enter Any Word, Here You will Predict that Which Character is inserted.*/
}
#Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
// TODO Auto-generated method stub
}
#Override
public void afterTextChanged(Editable s) {
// TODO Auto-generated method stub
}
});
OR
As #Saket Suggested.
if you are using TextView for Text watching then use AutoCompleteTextView with below code.
ArrayAdapter<String> aCustListAdapterNo = new ArrayAdapter<String>(
mContext, android.R.layout.select_dialog_item,
fillAutoCompleteCustomerListNo);
**autoCompletetxtViewCUSListNo.setThreshold(1);**
autoCompletetxtViewCUSListNo.setAdapter(aCustListAdapterNo);
Hope this helps you.

android on Text Change Listener

I have a situation, where there are two fields. field1 and field2. All I want
to do is empty field2 when field1 is changed and vice versa. So at the end only
one field has content on it.
field1 = (EditText)findViewById(R.id.field1);
field2 = (EditText)findViewById(R.id.field2);
field1.addTextChangedListener(new TextWatcher() {
public void afterTextChanged(Editable s) {}
public void beforeTextChanged(CharSequence s, int start,
int count, int after) {
}
public void onTextChanged(CharSequence s, int start,
int before, int count) {
field2.setText("");
}
});
field2.addTextChangedListener(new TextWatcher() {
public void afterTextChanged(Editable s) {}
public void beforeTextChanged(CharSequence s, int start,
int count, int after) {
}
public void onTextChanged(CharSequence s, int start,
int before, int count) {
field1.setText("");
}
});
It works fine if I attach addTextChangedListener to field1 only, but when
I do it for both fields the app crashes. Obviously because they try to change
each other indefinitely. Once field1 changes it clears field2 at this moment
field2 is changed so it will clear field1 and so on...
Can someone suggest any solution?
You can add a check to only clear when the text in the field is not empty (i.e when the length is different than 0).
field1.addTextChangedListener(new TextWatcher() {
#Override
public void afterTextChanged(Editable s) {}
#Override
public void beforeTextChanged(CharSequence s, int start,
int count, int after) {
}
#Override
public void onTextChanged(CharSequence s, int start,
int before, int count) {
if(s.length() != 0)
field2.setText("");
}
});
field2.addTextChangedListener(new TextWatcher() {
#Override
public void afterTextChanged(Editable s) {}
#Override
public void beforeTextChanged(CharSequence s, int start,
int count, int after) {
}
#Override
public void onTextChanged(CharSequence s, int start,
int before, int count) {
if(s.length() != 0)
field1.setText("");
}
});
Documentation for TextWatcher here.
Also please respect naming conventions.
In Kotlin simply use KTX extension function:
(It uses TextWatcher)
yourEditText.doOnTextChanged { text, start, count, after ->
// action which will be invoked when the text is changing
}
import core-KTX:
implementation "androidx.core:core-ktx:1.2.0"
I know this is old but someone might come across this again someday.
I had a similar problem where I would call setText on a EditText and onTextChanged would be called when I didn't want it to. My first solution was to write some code after calling setText() to undo the damage done by the listener. But that wasn't very elegant.
After doing some research and testing I discovered that using getText().clear() clears the text in much the same way as setText(""), but since it isn't setting the text the listener isn't called, so that solved my problem. I switched all my setText("") calls to getText().clear() and I didn't need the bandages anymore, so maybe that will solve your problem too.
Try this:
Field1 = (EditText)findViewById(R.id.field1);
Field2 = (EditText)findViewById(R.id.field2);
Field1.addTextChangedListener(new TextWatcher() {
public void afterTextChanged(Editable s) {}
public void beforeTextChanged(CharSequence s, int start,
int count, int after) {
}
public void onTextChanged(CharSequence s, int start,
int before, int count) {
Field2.getText().clear();
}
});
Field2.addTextChangedListener(new TextWatcher() {
public void afterTextChanged(Editable s) {}
public void beforeTextChanged(CharSequence s, int start,
int count, int after) {
}
public void onTextChanged(CharSequence s, int start,
int before, int count) {
Field1.getText().clear();
}
});
If you are using Kotlin for Android development then you can add TextChangedListener() using this code:
myTextField.addTextChangedListener(object : TextWatcher{
override fun afterTextChanged(s: Editable?) {}
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {}
override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {}
})
var filenameText = findViewById(R.id.filename) as EditText
filenameText.addTextChangedListener(object : TextWatcher {
override fun afterTextChanged(s: Editable?) {
filename = filenameText.text.toString()
Log.i("FileName: ", filename)
}
override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {}
override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {}
})
A bit late of a answer, but here is a reusable solution:
/**
* An extension of TextWatcher which stops further callbacks being called as
* a result of a change happening within the callbacks themselves.
*/
public abstract class EditableTextWatcher implements TextWatcher {
private boolean editing;
#Override
public final void beforeTextChanged(CharSequence s, int start,
int count, int after) {
if (editing)
return;
editing = true;
try {
beforeTextChange(s, start, count, after);
} finally {
editing = false;
}
}
protected abstract void beforeTextChange(CharSequence s, int start,
int count, int after);
#Override
public final void onTextChanged(CharSequence s, int start,
int before, int count) {
if (editing)
return;
editing = true;
try {
onTextChange(s, start, before, count);
} finally {
editing = false;
}
}
protected abstract void onTextChange(CharSequence s, int start,
int before, int count);
#Override
public final void afterTextChanged(Editable s) {
if (editing)
return;
editing = true;
try {
afterTextChange(s);
} finally {
editing = false;
}
}
public boolean isEditing() {
return editing;
}
protected abstract void afterTextChange(Editable s);
}
So when the above is used, any setText() calls happening within the TextWatcher will not result in the TextWatcher being called again:
/**
* A setText() call in any of the callbacks below will not result in TextWatcher being
* called again.
*/
public class MyTextWatcher extends EditableTextWatcher {
#Override
protected void beforeTextChange(CharSequence s, int start, int count, int after) {
}
#Override
protected void onTextChange(CharSequence s, int start, int before, int count) {
}
#Override
protected void afterTextChange(Editable s) {
}
}
I wrote my own extension for this, very helpful for me. (Kotlin)
You can write only like that :
editText.customAfterTextChanged { editable ->
//You have accessed the editable object.
}
My extension :
fun EditText.customAfterTextChanged(action: (Editable?)-> Unit){
this.addTextChangedListener(object : TextWatcher {
override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {}
override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {}
override fun afterTextChanged(editable: Editable?) {
action(editable)
}
})}
I have also faced the same problem and keep on getting stackOverflow exceptions, and I come with the following solution.
edt_amnt_sent.addTextChangedListener(new TextWatcher() {
#Override
public void afterTextChanged(Editable s) {
if (skipOnChange)
return;
skipOnChange = true;
try {
//method
} catch (NumberFormatException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
skipOnChange = false;
}
}
});
edt_amnt_receive.addTextChangedListener(new TextWatcher() {
#Override
public void afterTextChanged(Editable s) {
if (skipOnChange)
return;
skipOnChange = true;
try {
//method
} catch (NumberFormatException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
skipOnChange = false;
}
}
});
declared initially boolean skipOnChange = false;
You can also use the hasFocus() method:
public void onTextChanged(CharSequence s, int start,
int before, int count) {
if (Field2.hasfocus()){
Field1.setText("");
}
}
Tested this for a college assignment I was working on to convert temperature scales as the user typed them in. Worked perfectly, and it's way simpler.
check String before set another EditText to empty. if Field1 is empty then why need to change again to ( "" )? so you can check the size of Your String with s.lenght() or any other solution
another way that you can check lenght of String is:
String sUsername = Field1.getText().toString();
if (!sUsername.matches(""))
{
// do your job
}
editText.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
#Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
if (noteid != -1) {
MainActivity.notes.set(noteid, String.valueOf(charSequence));
MainActivity.arrayAdapter.notifyDataSetChanged();
}
}
#Override
public void afterTextChanged(Editable editable) {
}
});
in this code noteid is basically arguments taken back which is being putted into the indent or passed through the indent.
Intent intent = getIntent();
noteid = intent.getIntExtra("noteid", -1);
the code on the downside is basically the extra code ,if you want to understand more clearly.
how to make the menu or insert the menu in our code ,
create the menu folder this the folder created by going into the raw
->rightclick->
directory->name the folder as you wish->
then click on the directory formed->
then click on new file and then name for file as you wish ie the folder name file
and now type the 2 lines code in it and see the magic.
new activity code named as NoteEditor.java for editing purpose,my app is basicley the note app.
package com.example.elavi.notes;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.widget.EditText;
import android.widget.Toast;
import static android.media.CamcorderProfile.get;
public class NoteEditorActivity extends AppCompatActivity {
EditText editText;
int noteid;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_note_editor);
editText = findViewById(R.id.editText);
Intent intent = getIntent();
noteid = intent.getIntExtra("noteid", -1);
if (noteid != -1) {
String text = MainActivity.notes.get(noteid);
editText.setText(text);
Toast.makeText(getApplicationContext(),"The arraylist content is"+MainActivity.notes.get(noteid),Toast.LENGTH_SHORT).show();
}
else
{
Toast.makeText(getApplicationContext(),"Here we go",Toast.LENGTH_SHORT).show();
MainActivity.notes.add("");
noteid=MainActivity.notes.size()-1;
}
editText.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
#Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
if (noteid != -1) {
MainActivity.notes.set(noteid, String.valueOf(charSequence));
MainActivity.arrayAdapter.notifyDataSetChanged();
}
}
#Override
public void afterTextChanged(Editable editable) {
}
});
}
}
We can remove the TextWatcher for a field just before editing its text then add it back after editing the text.
Declare Text Watchers for both field1 and field2 as separate variables to give them a name: e.g. for field1
private TextWatcher Field_1_Watcher = new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
#Override
public void afterTextChanged(Editable s) {
}
#Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
}
};
then add the watcher using its name:
field1.addTextChangedListener(Field_1_Watcher) for field1, and
field2.addTextChangedListener(Field_2_Watcher) for field2
Before changing the field2 text remove the TextWatcher:
field2.removeTextChangedListener(Field_2_Watcher)
change the text:
field2.setText("")
then add the TextWatcher back:
field2.addTextChangedListener(Field_2_Watcher)
Do the same for the other field
Another solution that may help someone. There are 2 EditText which change instead of each other after editing. By default, it led to cyclicity.
use variable:
Boolean uahEdited = false;
Boolean usdEdited = false;
add TextWatcher
uahEdit = findViewById(R.id.uahEdit);
usdEdit = findViewById(R.id.usdEdit);
uahEdit.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
if (!usdEdited) {
uahEdited = true;
}
}
#Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
String tmp = uahEdit.getText().toString();
if(!tmp.isEmpty() && uahEdited) {
uah = Double.valueOf(tmp);
usd = uah / 27;
usdEdit.setText(String.valueOf(usd));
} else if (tmp.isEmpty()) {
usdEdit.getText().clear();
}
}
#Override
public void afterTextChanged(Editable s) {
uahEdited = false;
}
});
usdEdit.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
if (!uahEdited) {
usdEdited = true;
}
}
#Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
String tmp = usdEdit.getText().toString();
if (!tmp.isEmpty() && usdEdited) {
usd = Double.valueOf(tmp);
uah = usd * 27;
uahEdit.setText(String.valueOf(uah));
} else if (tmp.isEmpty()) {
uahEdit.getText().clear();
}
}
#Override
public void afterTextChanged(Editable s) {
usdEdited = false;
}
});
Don't criticize too much. I am a novice developer
etSearch.addTextChangedListener(object : TextWatcher {
override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
TODO("Not yet implemented")
}
override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
TODO("Not yet implemented")
}
override fun afterTextChanged(p0: Editable?) {
TODO("Not yet implemented")
}
})
you use this
I have provided latest method for textchangelistner
edMsg.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
#Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
if (i2 == 0){
////Edit text blanked
}
String msg = charSequence.toString();/// your text on changed in edit text
}
#Override
public void afterTextChanged(Editable editable) {
}
});
editText.addTextChangedListener(new TextWatcher()
{
#Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2)
{
}
#Override
public void onTextChanged(CharSequence chr, int i, int i1, int i2)
{
//Check char sequence is empty or not
if (chr.length() > 0)
{
//Your Code Here
}
}
#Override
public void afterTextChanged(Editable editable)
{
}
});
Add background dynamically in onCreate method:
getWindow().setBackgroundDrawableResource(R.drawable.background);
also remove background from XML.

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