"Swipe Detection" attached to textview is malfunctioning

Question

I am trying to detect "Left Swipe", "Right Swipe" and "Down Swipe".

Please have a look at the Following code

ParagraphReader.java

package k.k;

import java.util.ArrayList;
import java.util.List;
import java.util.Locale;

import android.os.Bundle;
import android.app.Activity;
import android.speech.tts.TextToSpeech;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnTouchListener;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

public class ParagraphReader extends Activity implements TextToSpeech.OnInitListener {

    private TextView paraText;
    private TextView paraListQuestionIndicator;
    private ImageView speaker;
    private DatabaseConnector database;
    private List<String>paraList;
    private int currentQuestion;

    private TextToSpeech tts;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_paragraph_reader);

        paraText = (TextView)findViewById(R.id.paragraph_reader_txt);
        paraText.setOnTouchListener(paraSwiped);

        paraListQuestionIndicator = (TextView)findViewById(R.id.paralist_question_indicator);

        speaker = (ImageView)findViewById(R.id.speak);
        speaker.setOnClickListener(new SpeakOutTheText());

        paraList = new ArrayList<String>();
        database = DatabaseHandler.getInstance(this);

        tts = new TextToSpeech(this,this);

        //Get the Paragraph list
        int listNumber = getIntent().getIntExtra("PARAGRAPH_LIST", 0);

        //Toast.makeText(this, "Selected Paragraph: "+listNumber, Toast.LENGTH_LONG).show();

        paraList = database.getParagraphList(listNumber);
        //Toast.makeText(this, "ParaList size "+paraList.size(), Toast.LENGTH_LONG).show();

        //Toast.makeText(this, "Size: "+paraList.size(), Toast.LENGTH_LONG).show();
        paraText.setText(paraList.get(0));
        setParaListQuestionIndicator(currentQuestion);


    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.paragraph_reader, menu);
        return true;
    }


    //The Event Handler for the Paragraph Text holder
    OnTouchListener paraSwiped = new OnSwipeTouchListener()
    {
        public boolean onSwipeRight() 
         {
            //Toast.makeText(ParagraphReader.this, "Right: "+paraList.size(), Toast.LENGTH_SHORT).show();
            currentQuestion--;

            if(currentQuestion<0)
            {
                currentQuestion = paraList.size()-1;
            }

            paraText.setText(paraList.get(currentQuestion));    
            setParaListQuestionIndicator(currentQuestion);
            return true;
         }

          public boolean onSwipeLeft() 
          {
              //Toast.makeText(ParagraphReader.this, "Left: "+paraList.size(), Toast.LENGTH_SHORT).show();
              currentQuestion++;

              if(currentQuestion>paraList.size()-1)
              {
                  currentQuestion = 0;
              }

              paraText.setText(paraList.get(currentQuestion));
              setParaListQuestionIndicator(currentQuestion);

                return true;
          }

          public boolean onSwipeBottom()
          {
              return true;
          }


    };

    private class SpeakOutTheText implements OnClickListener
    {

        @Override
        public void onClick(View v) 
        {
            // TODO Auto-generated method stub
            speak(paraText.getText().toString());

        }

    }

    private void setParaListQuestionIndicator(int number)
    {
        paraListQuestionIndicator.setText((number+1)+"/"+paraList.size());
    }



    @Override
    public void onInit(int status) 
    {
        // TODO Auto-generated method stub
        if(status==TextToSpeech.SUCCESS)
        {
            int result = tts.setLanguage(Locale.UK);

            if(result==TextToSpeech.LANG_MISSING_DATA || result == TextToSpeech.LANG_NOT_SUPPORTED)
            {
                Toast.makeText(this, "Language Not Supported", Toast.LENGTH_LONG).show();
            }
        }


    }

    @Override
    public void onDestroy()
    {
        if(tts!=null)
        {
            tts.stop();
            tts.shutdown();
        }
        super.onDestroy();
    }



    public void speak(String text)
    {
        tts.speak(text, TextToSpeech.QUEUE_FLUSH, null);
    }

}

ParagraphReader.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".ParagraphReader" >

    <ScrollView
        android:id="@+id/paragraph_reader_scroll_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        >
        <TextView
            android:id="@+id/paragraph_reader_txt"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:minHeight="200dp"
            android:ems="30"
            android:singleLine="false"
            android:clickable="true"
            >


        </TextView>

    </ScrollView>

    <TextView
        android:id="@+id/paralist_question_indicator"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:text="text"
        android:textAppearance="?android:attr/textAppearanceMedium" />

    <ImageView
        android:id="@+id/speak"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:layout_marginRight="20dp"
        android:src="@drawable/speaker2" />

</RelativeLayout>

And the Gesture detection code,

OnSwipeTouchListener.java

This code is from here

package k.k;
import android.view.GestureDetector;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;

public class OnSwipeTouchListener implements OnTouchListener {

    private final GestureDetector gestureDetector = new GestureDetector(new GestureListener());

    public boolean onTouch(final View v, final MotionEvent event) {
        return gestureDetector.onTouchEvent(event);

    }

    private final class GestureListener extends SimpleOnGestureListener {

        private static final int SWIPE_THRESHOLD = 100;
        private static final int SWIPE_VELOCITY_THRESHOLD = 100;

        @Override
        public boolean onDown(MotionEvent e) {
            return super.onDown(e);
        }

        @Override
        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
            boolean result = false;
            try {
                float diffY = e2.getY() - e1.getY();
                float diffX = e2.getX() - e1.getX();
                if (Math.abs(diffX) > Math.abs(diffY)) {
                    if (Math.abs(diffX) > SWIPE_THRESHOLD && Math.abs(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
                        if (diffX > 0) {
                            result = onSwipeRight();
                        } else {
                            result = onSwipeLeft();
                        }
                    }
                } else {
                    if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
                        if (diffY > 0) {
                            result = onSwipeBottom();
                        } else {
                            result = onSwipeTop();
                        }
                    }
                }
            } catch (Exception exception) {
                exception.printStackTrace();
            }
            return result;
        }
    }

    public boolean onSwipeRight() {
        return false;
    }

    public boolean onSwipeLeft() {
        return false;
    }

    public boolean onSwipeTop() {
        return false;
    }

    public boolean onSwipeBottom() {
        return false;
    }
}

This code works fine as it should in Virtual Device, but to my surprise, it is not working on real device! I have Micromax Canvas2, and I tested with my phone and HP phone, in both this is not working.

Not working means, I think it do not identify any of the swipes properly. "Sometimes" it does swipe to left and right, but that is "sometimes" and for that also I had to drag it very hard 3-4 times.

What is wrong here? This is not working because I implemented the listener to a TextView?

PS: I posted the completed related classes here because last time it was impossible to get a suitable answer with code removed.

score 1 · Accepted Answer · answered Aug 30 '13 at 18:06

1

I found the answer. The case is, here what I have is a ScrollView which is by default responding to swipes and my text view was inside that. So, the only fix was taking the TextView out of the ScrollView.

answered Aug 30 '13 at 18:06

PeakGen

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MikeKeepsOnShine · Answer 2 · 2013-08-28T08:18:25.590

Did you try to wrap the TextView in a container (Linear/RelativeLayout) and implement the listener to the container? For example:

...

    <LinearLayout
        android:id="@+id/container"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">


    <TextView
        android:id="@+id/paragraph_reader_txt"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:minHeight="200dp"
        android:ems="30"
        android:singleLine="false"
        android:clickable="true"
        >


    </TextView>

    </LinearLayout>
...

and then:

LinearLayout parag = (LinearLayout)findViewById(R.id.container);
parag.setOnTouchListener(paraSwiped);

EDIT: I used swipe like so:

parag.setOnTouchListener(new OnSwipeTouchListener(){
        public boolean onSwipeRight(){
            //your stuff
            return true;
        }
        public boolean onSwipeLeft(){
            //your stuff
            return true;
        }

        ...
    });

It works for me

Hello, thanks for the reply. I just tried it, but still no good :( — PeakGen, Aug 28 '13 at 07:58
Mmh ... ok, i'm going to edit my answer, showing you how i used LeftSwipe and RightSwipe. I'm not sure that it will be helpful for your situation, but i try ;) — MikeKeepsOnShine, Aug 28 '13 at 08:10
I eally don't understand. Now I am not getting anythnig, even in the virtual device :( — PeakGen, Aug 28 '13 at 12:43

"Swipe Detection" attached to textview is malfunctioning

2 Answers2