'Android Kotlin: onTextChanged not being triggered for EditText

I am creating an EditText box with line numbers on the side. To achieve this, I have code in the onTextChanged method of the addTextChangedListener that updates the line numbers for the EditText. For some reason however, the onTextChanged event never seems to fire when I type in the EditText, as the println statement is not being activated.

Below is my XML code:

<GridLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:rowCount="1"
    android:columnCount="2">

    <TextView
        android:id="@+id/linenumber"
        android:layout_width="30dp"
        android:layout_height="200dp"
        android:layout_row="0"
        android:layout_column="0"
        android:layout_columnSpan="1"
        android:layout_alignParentStart="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:layout_alignParentBottom="true"
        android:background="@drawable/border_style"
        android:gravity="center_horizontal"
        android:text="1"
        android:textSize="18dp"></TextView>

    <EditText
        android:id="@+id/textbox"
        android:layout_width="0dp"
        android:layout_height="200dp"
        android:layout_row="0"
        android:layout_column="1"
        android:layout_columnSpan="1"
        android:layout_columnWeight="1"
        android:ems="5"
        android:gravity="left|top"
        android:inputType="textMultiLine"
        android:padding="10dp"
        android:text="" />
</GridLayout>

Below is my Kotlin code:

var textbox1: EditText = findViewById(R.id.textbox);
var lineNumber: TextView = findViewById(R.id.linenumber);

// Add the line numbers or remove the line numbers based on the user's input
textbox1.addTextChangedListener(object : TextWatcher {
    override fun afterTextChanged(p0: Editable?) {
    }

    override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
    }

    override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
        // Retrieve the number of lines in the user's input
        var lines:Int = lineNumber.getLineCount()
        var linesText:String = "";

        // Loop through the lines
        for (i in 1..lines) {
            linesText = linesText + "\n" + i;
        }

        println("linesText = " + linesText)
        // Update the line numbers
        lineNumber.setText(linesText);
    }
})

Solution 1:^[1]

I figured out the bug and I apologize for not including the line of code in my post where the bug was:

I had the following extra line of code that reset the listener after I initialized the listener:

setContentView(R.layout.activity_main)

Solution 2:^[2]

The only problem I can spot is:

var lines:Int = lineNumber.getLineCount()

Shouldn't this be:

var lines : Int = textbox1.getLineCount()

Also your listener in this instance should be added in onCreate() or onResume().

Solution 3:^[3]

In case somebody lands here, android:textAllCaps="true" in EditText prevented for some reason onTextChanged from being called in my project.

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution	Source
Solution 1	Adam Lee
Solution 2	Scott Evans
Solution 3	Amir Golan

'Android Kotlin: onTextChanged not being triggered for EditText

Solution 1:[1]

Solution 2:[2]

Solution 3:[3]

Sources

Related Questions

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