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?
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
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) {
}
}
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
}
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) {}
})
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();
}
});
Add background dynamically in onCreate method:
getWindow().setBackgroundDrawableResource(R.drawable.background);
also remove background from XML.
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) {
}
});
}
}
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) {}
})
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.
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 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)
}
})}
Source: Stackoverflow.com