Hi I'm using this library with Android API23(mashmellow)

[json91-dev]

when i was using this library , i can see seekbar in the layout preview.

However, when i build and start with my application,

seekbar is invisible in the application running.

I follow all steps, and i think there is no reson do like that.

Here is my layout source

<org.opencv.android.JavaCameraView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/activity_surface_view" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="size"
    android:textColor="#FFE400"
    android:layout_marginTop="5dp"
    android:layout_marginRight="3dp"
    android:layout_toLeftOf="@+id/seekbar1"
    />


<com.h6ah4i.android.widget.verticalseekbar.VerticalSeekBarWrapper
    android:id="@+id/seekbar1"
    android:layout_width="wrap_content"
    android:layout_height="140dp"
    android:layout_alignParentRight="true"
    android:layout_marginRight="20dp"
    >

    <com.h6ah4i.android.widget.verticalseekbar.VerticalSeekBar
        android:id="@+id/sizeseekvar"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_alignParentTop="true"
        android:layout_marginLeft="18dp"
        android:layout_marginStart="18dp"
        android:layout_toEndOf="@+id/masklistview"
        android:layout_toRightOf="@+id/masklistview"
        android:splitTrack="false"
        app:seekBarRotation="CW270"
        android:max="150"
        android:min="50"
        android:progress="100"


        />

</com.h6ah4i.android.widget.verticalseekbar.VerticalSeekBarWrapper>

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="height"
    android:textColor="#FFE400"
    android:layout_marginTop="15dp"
    android:layout_marginRight="3dp"
    android:layout_below="@id/camerabutton"
    android:layout_toLeftOf="@id/seekbar2"

    />



<com.h6ah4i.android.widget.verticalseekbar.VerticalSeekBarWrapper
    android:id="@+id/seekbar2"
    android:layout_width="wrap_content"
    android:layout_height="140dp"
    android:layout_alignLeft="@+id/seekbar1"
    android:layout_alignParentBottom="true"
    android:layout_alignStart="@+id/seekbar1">

    <com.h6ah4i.android.widget.verticalseekbar.VerticalSeekBar
        android:id="@+id/heightseekvar"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_alignParentTop="true"
        android:layout_marginLeft="18dp"

        android:layout_marginStart="18dp"
        android:layout_toEndOf="@+id/masklistview"
        android:layout_toRightOf="@+id/masklistview"
        android:max="150"
        android:min="50"
        android:progress="100"
        android:splitTrack="false"
        app:seekBarRotation="CW270" />

</com.h6ah4i.android.widget.verticalseekbar.VerticalSeekBarWrapper>




<ListView
    android:id="@+id/masklistview"
    android:layout_width="150dp"
    android:layout_height="match_parent"
    android:background="#ffffff"
    >
</ListView>
<ImageButton

    android:id="@+id/camerabutton"
    android:layout_width="60dp"
    android:layout_height="60dp"
    android:background="@android:color/transparent"
    android:src="@drawable/camerabutton3"
    android:layout_alignParentRight="true"
    android:scaleType="fitXY"
    android:layout_centerVertical="true"


    />

<com.h6ah4i.android.widget.verticalseekbar.VerticalSeekBar
    android:id="@+id/mySeekBar2"
    android:layout_width="0dp"
    android:layout_height="0dp"

    android:layout_alignParentTop="true"
    android:layout_marginEnd="32dp"
    android:layout_marginRight="32dp"
    android:layout_marginTop="41dp"
    android:layout_toLeftOf="@+id/camerabutton"
    android:layout_toStartOf="@+id/camerabutton"
    android:splitTrack="false"
    app:seekBarRotation="CW90" />

this is java source

SeekBar sizeseekbar,heightseekbar;

sizeseekbar=(SeekBar)findViewById(R.id.sizeseekvar);
sizeseekbar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@OverRide
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {

            sizeratio=progress/100;
        }

        @Override
        public void onStartTrackingTouch(SeekBar seekBar) {}

        @Override
        public void onStopTrackingTouch(SeekBar seekBar) {}
    });

    heightseekbar=(SeekBar)findViewById(R.id.heightseekvar);
    heightseekbar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
        @Override
        public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {

            Toast.makeText(getApplicationContext(),"동작??",Toast.LENGTH_LONG).show();
            heightratio=progress/100;
        }

        @Override
        public void onStartTrackingTouch(SeekBar seekBar) {}

        @Override
        public void onStopTrackingTouch(SeekBar seekBar) {}
    });

if you answer me , I will so appreciate it. Thank you