0

I have a TextView with the users password, and I have to let them to show/hide it. So I created a button with the show/hide functionality.

When the password is in hide mode, I need to show the same number of dots, for example five dots.

I wrote the next code, but when the password is trying to hide, I obtain an error. (Wrote below)

Can someone help me?

The code:

public class CustomPasswordTransformation  extends PasswordTransformationMethod {

    @Override
    public CharSequence getTransformation(CharSequence source, View view) {
        return new PasswordCharSequence(source);
    }

    private class PasswordCharSequence implements CharSequence {
        private CharSequence mSource;

        public PasswordCharSequence(CharSequence source) {
            mSource = source;
        }
        public char charAt(int index) {
            return '*';
        }
        public int length() {
            return 5;
        }
        public CharSequence subSequence(int start, int end) {
            return mSource.subSequence(start, end); 
        }
    }
}

And this is the error:

E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.debug, PID: 19891
java.lang.IndexOutOfBoundsException
    at android.graphics.Paint.getRunAdvance(Paint.java:2346)
    at android.text.TextLine.handleText(TextLine.java:748)
    at android.text.TextLine.handleRun(TextLine.java:898)
    at android.text.TextLine.measureRun(TextLine.java:417)
    at android.text.TextLine.measure(TextLine.java:296)
    at android.text.TextLine.metrics(TextLine.java:270)
    at android.text.Layout.getLineExtent(Layout.java:1053)
    at android.text.Layout.getLineWidth(Layout.java:1019)
    at android.widget.TextView.desired(TextView.java:6811)
    at android.widget.TextView.onMeasure(TextView.java:6877)
    at android.view.View.measure(View.java:18850)
    at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5963)
    at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1465)
    at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:1112)
    at android.widget.LinearLayout.onMeasure(LinearLayout.java:632)
    at android.view.View.measure(View.java:18850)
    at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5963)
    at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1465)
    at android.widget.LinearLayout.measureVertical(LinearLayout.java:748)
    at android.widget.LinearLayout.onMeasure(LinearLayout.java:630)
    at android.view.View.measure(View.java:18850)
    at android.widget.RelativeLayout.measureChild(RelativeLayout.java:677)
    at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:480)
    at android.view.View.measure(View.java:18850)
    at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5963)
    at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1465)
    at android.widget.LinearLayout.measureVertical(LinearLayout.java:748)
    at android.widget.LinearLayout.onMeasure(LinearLayout.java:630)
    at android.view.View.measure(View.java:18850)
    at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5963)
    at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1465)
    at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:1112)
    at android.widget.LinearLayout.onMeasure(LinearLayout.java:632)
    at android.view.View.measure(View.java:18850)
    at android.support.v7.widget.RecyclerView$LayoutManager.measureChildWithMargins(RecyclerView.java:8994)
    at android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1585)
    at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1519)
    at android.support.v7.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:614)
    at android.support.v7.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:3812)
    at android.support.v7.widget.RecyclerView.dispatchLayout(RecyclerView.java:3529)
    at android.support.v7.widget.RecyclerView.onLayout(RecyclerView.java:4082)
    at android.view.View.layout(View.java:16692)
    at android.view.ViewGroup.layout(ViewGroup.java:5449)
    at android.support.v4.widget.SwipeRefreshLayout.onLayout(SwipeRefreshLayout.java:606)
    at android.view.View.layout(View.java:16692)
    at android.view.ViewGroup.layout(ViewGroup.java:5449)
    at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1743)
    at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1586)
    at android.widget.LinearLayout.onLayout(LinearLayout.java:1495)
    at android.view.View.layout(View.java:16692)
    at android.view.ViewGroup.layout(ViewGroup.java:5449)
    at android.support.v4.view.ViewPager.onLayout(ViewPager.java:1769)
    at android.view.View.layout(View.java:16692)
    at android.view.ViewGroup.layout(ViewGroup.java:5449)
    at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1743)
    at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1586)
    at android.widget.LinearLayout.onLayout(LinearLayout.java:1495)
    at android.view.View.layout(View.java:16692)
    at android.view.ViewGroup.layout(ViewGroup.java:5449)
    at android.widget.FrameLayout.layoutChildren(FrameLayout.java:336)
    at android.widget.FrameLayout.onLayout(Fram
Pablo Garcia
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  • Instead of replacing the characters with dots yourself, you can ask the system to do it for you. Look at https://stackoverflow.com/questions/3685790/how-to-switch-between-hide-and-view-password – Rishabh Jain Apr 26 '19 at 08:34

1 Answers1

0

You need to return length of charsequence which you entered in input.

In your code you need to replace 5 with source.length() in length function.

public class CustomPasswordTransformation extends PasswordTransformationMethod {

@Override
public CharSequence getTransformation(CharSequence source, View view) {
    return new PasswordCharSequence(source);
}

private class PasswordCharSequence implements CharSequence {
    private CharSequence mSource;

    public PasswordCharSequence(CharSequence source) {
        mSource = source;
    }
    public char charAt(int index) {
        return '*';
    }
    public int length() {
        return source.length();
    }
    public CharSequence subSequence(int start, int end) {
        return mSource.subSequence(start, end); 
    }
}

}

VIKAS SHARMA
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