Seekbar的setThumb使用记录

        <SeekBar
            android:id="@+id/seek_bar_1"
            android:layout_width="920dp"
            android:layout_height="40dp"
            android:max="100"
            android:progress="100"
            android:progressDrawable="@drawable/seek_bar_bg_2"
            android:thumb="@drawable/seek_thumb"
            android:thumbOffset="0dp" />

  android:thumbOffset="0dp"

public void setThumb(Drawable thumb) {
    //略
    if (thumb != null) {
        // Assuming the thumb drawable is symmetric, set the thumb offset
        // such that the thumb will hang halfway off either edge of the
        // progress bar.
        mThumbOffset = thumb.getIntrinsicWidth() / 2;
    }
	//略
}