<declare-styleable name="MySeekBar">    <attr name="textsize" format="dimension" />    <attr name="textcolor" format="color" />    <attr name="img" format="reference" /></declare-styleable>

 <com.jzh.myseekbar.MySeekBar      android:id="@+id/seekBar"      android:layout_width="match_parent"      android:layout_height="wrap_content"      android:layout_weight="1"      android:max="80"      android:maxHeight="10dp"      android:progress="0"      android:progressDrawable="@drawable/seekbar_style"       android:splitTrack="false"      android:thumb="@mipmap/niu"      app:img="@mipmap/ann"      app:textcolor="#fff"      app:textsize="14dp" />

<?xml version="1.0" encoding="utf-8"?><layer-list xmlns:android="http://schemas.android.com/apk/res/android">   <item android:id="@android:id/background">     <shape>      <corners android:radius="5dp" />      <gradient        android:angle="0"        android:centerColor="@android:color/holo_orange_dark"        android:endColor="@android:color/holo_red_dark"        android:startColor="#2aade3" />    </shape>  </item>  </layer-list>

/**   * 文本的顏色   */  private int mTitleTextColor;  /**   * 文本的大小   */  private float mTitleTextSize;  private String mTitleText;//文字的內容   /**   * 背景圖片   */  private int img;  private Bitmap map;  //bitmap對應的寬高  private float img_width, img_height;  Paint paint;   private float numTextWidth;  //測量seekbar的規格  private Rect rect_seek;  private Paint.FontMetrics fm;   public static final int TEXT_ALIGN_LEFT = 0x00000001;  public static final int TEXT_ALIGN_RIGHT = 0x00000010;  public static final int TEXT_ALIGN_CENTER_VERTICAL = 0x00000100;  public static final int TEXT_ALIGN_CENTER_HORIZONTAL = 0x00001000;  public static final int TEXT_ALIGN_TOP = 0x00010000;  public static final int TEXT_ALIGN_BOTTOM = 0x00100000;  /**   * 文本中軸線X坐標   */  private float textCenterX;  /**   * 文本baseline線Y坐標   */  private float textBaselineY;  /**   * 文字的方位   */  private int textAlign;   public MySeekBar(Context context) {    this(context, null);  }   public MySeekBar(Context context, AttributeSet attrs) {    this(context, attrs, 0);  }   public MySeekBar(Context context, AttributeSet attrs, int defStyleAttr) {    super(context, attrs, defStyleAttr);    TypedArray array = context.getTheme().obtainStyledAttributes(attrs, R.styleable.MySeekBar, defStyleAttr, 0);    int n = array.getIndexCount();    for (int i = 0; i < n; i++) {      int attr = array.getIndex(i);      switch (attr) {        case R.styleable.MySeekBar_textsize:          mTitleTextSize = array.getDimension(attr, 15f);          break;        case R.styleable.MySeekBar_textcolor:          mTitleTextColor = array.getColor(attr, Color.WHITE);          break;        case R.styleable.MySeekBar_img:          img = array.getResourceId(attr, R.mipmap.ic_launcher);          break;      }    }    array.recycle();    getImgWH();    paint = new Paint();    paint.setAntiAlias(true);//設置抗鋸齒    paint.setTextSize(mTitleTextSize);//設置文字大小    paint.setColor(mTitleTextColor);//設置文字顏色    //設置控件的padding 給提示文字留出位置    setPadding((int) Math.ceil(img_width) / 2, 0, (int) Math.ceil(img_height) / 2, (int) Math.ceil(img_height) + 10);    textAlign = TEXT_ALIGN_CENTER_HORIZONTAL | TEXT_ALIGN_CENTER_VERTICAL;  }   /**   * 獲取圖片的寬高   */  private void getImgWH() {    map = BitmapFactory.decodeResource(getResources(), img);    img_width = map.getWidth();    img_height = map.getHeight();    }   @Override  protected synchronized void onDraw(Canvas canvas) {    super.onDraw(canvas);    setTextLocation();//定位文本繪制的位置    rect_seek = this.getProgressDrawable().getBounds();    //定位文字背景圖片的位置    float bm_x = rect_seek.width() * getProgress() / getMax();    float bm_y = rect_seek.height() + 20;//    //計算文字的中心位置在bitmap    float text_x = rect_seek.width() * getProgress() / getMax() + (img_width - numTextWidth) / 2;    canvas.drawBitmap(map, bm_x, bm_y, paint);//畫背景圖    // canvas.drawRoundRect();    canvas.drawText(mTitleText, text_x, (float) (textBaselineY + bm_y + (0.16 * img_height / 2)), paint);//畫文字   }   @Override  public boolean onTouchEvent(MotionEvent event) {    invalidate();//監聽手勢滑動，不斷重繪文字和背景圖的顯示位置    return super.onTouchEvent(event);  }   /**   * 定位文本繪制的位置   */  private void setTextLocation() {     fm = paint.getFontMetrics();    //文本的寬度    mTitleText = getProgress() + 10 + "℃";     numTextWidth = paint.measureText(mTitleText);     float textCenterVerticalBaselineY = img_height / 2 - fm.descent + (fm.descent - fm.ascent) / 2;    switch (textAlign) {      case TEXT_ALIGN_CENTER_HORIZONTAL | TEXT_ALIGN_CENTER_VERTICAL:        textCenterX = img_width / 2;        textBaselineY = textCenterVerticalBaselineY;        break;      case TEXT_ALIGN_LEFT | TEXT_ALIGN_CENTER_VERTICAL:        textCenterX = numTextWidth / 2;        textBaselineY = textCenterVerticalBaselineY;        break;      case TEXT_ALIGN_RIGHT | TEXT_ALIGN_CENTER_VERTICAL:        textCenterX = img_width - numTextWidth / 2;        textBaselineY = textCenterVerticalBaselineY;        break;      case TEXT_ALIGN_BOTTOM | TEXT_ALIGN_CENTER_HORIZONTAL:        textCenterX = img_width / 2;        textBaselineY = img_height - fm.bottom;        break;      case TEXT_ALIGN_TOP | TEXT_ALIGN_CENTER_HORIZONTAL:        textCenterX = img_width / 2;        textBaselineY = -fm.ascent;        break;      case TEXT_ALIGN_TOP | TEXT_ALIGN_LEFT:        textCenterX = numTextWidth / 2;        textBaselineY = -fm.ascent;        break;      case TEXT_ALIGN_BOTTOM | TEXT_ALIGN_LEFT:        textCenterX = numTextWidth / 2;        textBaselineY = img_height - fm.bottom;        break;      case TEXT_ALIGN_TOP | TEXT_ALIGN_RIGHT:        textCenterX = img_width - numTextWidth / 2;        textBaselineY = -fm.ascent;        break;      case TEXT_ALIGN_BOTTOM | TEXT_ALIGN_RIGHT:        textCenterX = img_width - numTextWidth / 2;        textBaselineY = img_height - fm.bottom;        break;    }  }