Android - Vertical Seek Bar

http://stackoverflow.com/questions/4892179/how-can-i-get-a-working-vertical-seekbar-in-android (2013-02)

Siehe auch die Kommentare wg. Verbesserungen und Problembehebungen

package android.widget;

import android.content.Context;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.view.MotionEvent;

public class VerticalSeekBar extends SeekBar {

    public VerticalSeekBar(Context context) {
        super(context);
    }

    public VerticalSeekBar(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    public VerticalSeekBar(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(h, w, oldh, oldw);
    }

    @Override
    protected synchronized void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(heightMeasureSpec, widthMeasureSpec);
        setMeasuredDimension(getMeasuredHeight(), getMeasuredWidth());
    }

    protected void onDraw(Canvas c) {
        c.rotate(-90);
        c.translate(-getHeight(), 0);

        super.onDraw(c);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        if (!isEnabled()) {
            return false;
        }

        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
            case MotionEvent.ACTION_MOVE:
            case MotionEvent.ACTION_UP:
                setProgress(getMax() - (int) (getMax() * event.getY() / getHeight()));
                onSizeChanged(getWidth(), getHeight(), 0, 0);
                break;

            case MotionEvent.ACTION_CANCEL:
                break;
        }
        return true;
    }
}

Implementation To implement it, create a new class in your project, choosing the right package: android.widget

xml Layout

<android.widget.VerticalSeekBar
  android:id="@+id/seekBar1"
  android:layout_width="wrap_content"
  android:layout_height="200dp"
  />

Kommentare und Verbesserungen

This works absolutely correct. The only thing that should be mentioned is that you must be aware of the layout choice, if you choose lets say LinearLayout orientation of that layout really matters of how you will see the bar, thus the place of getMeasuredHeight() and width, will change setMeasuredDimension(getMeasuredHeight(), getMeasuredWidth());

The code given in the accepted answer didn't intercept the onStartTrackingTouch and the onStopTrackingTouch events, so I've modified it to have more control over this two events.

Here is my code:

public class VerticalSeekBar extends SeekBar {

private OnSeekBarChangeListener myListener;
public VerticalSeekBar(Context context) {
    super(context);
}

public VerticalSeekBar(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
}

public VerticalSeekBar(Context context, AttributeSet attrs) {
    super(context, attrs);
}

protected void onSizeChanged(int w, int h, int oldw, int oldh) {
    super.onSizeChanged(h, w, oldh, oldw);
}

@Override
protected synchronized void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(heightMeasureSpec, widthMeasureSpec);
    setMeasuredDimension(getMeasuredHeight(), getMeasuredWidth());
}

@Override
public void setOnSeekBarChangeListener(OnSeekBarChangeListener mListener){
    this.myListener = mListener;
}

protected void onDraw(Canvas c) {
    c.rotate(-90);
    c.translate(-getHeight(), 0);

    super.onDraw(c);
}

@Override
public boolean onTouchEvent(MotionEvent event) {
    if (!isEnabled()) {
        return false;
    }

    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            if(myListener!=null)
                myListener.onStartTrackingTouch(this);
            break;
        case MotionEvent.ACTION_MOVE:
            setProgress(getMax() - (int) (getMax() * event.getY() / getHeight()));
            onSizeChanged(getWidth(), getHeight(), 0, 0);
            myListener.onProgressChanged(this, getMax() - (int) (getMax() * event.getY() / getHeight()), true);
            break;
        case MotionEvent.ACTION_UP:
            myListener.onStopTrackingTouch(this);
            break;

        case MotionEvent.ACTION_CANCEL:
            break;
    }
    return true;
}
}

I had problem while using this code with setProgress method. To solve them I suggest overriding setProgress and adding onSizeChanged call to it.Added code here ..

   private int x,y,z,w;
   protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(h, w, oldh, oldw);
        this.x=w;
        this.y=h;
        this.z=oldw;
        this.w=oldh;
    }
        @Override
        public synchronized void setProgress(int progress) {

            super.setProgress(progress);

                onSizeChanged(x, y, z, w);

        }

selected hover actions are performed by adding the following code:

1.setPressed(true);setSelected(true);//Add this in ACTION_DOWN

2.setPressed(false);setSelected(false);//Add this in ACTION_UP

And Write code for selected hover options in ur xml.

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="true"
          android:state_window_focused="true"
          android:drawable="@drawable/thumb_h" />
    <item android:state_selected="true"
          android:state_window_focused="true"
          android:drawable="@drawable/thumb_h" />
    <item android:drawable="@drawable/thumb" />
</selector>