Android自定义Seekbar滑动条 Pop提示跟随滑动按钮滑动

本文实例为大家分享了Android自定义Seekbar滑动条的具体代码，供大家参考，具体内容如下

由于项目需要做出此效果，自定义写了一个。

效果图

思路：

原始的seekbar只有滑动条并没有下方的提示文字，所以我们必须要继承Seekbar重写这个控件。

代码：

在values文件夹下新建attrs.xml,用于设置跟随滑动按钮的文字大小，颜色，背景。

在布局里引用此控件

自定义控件样式

主要核心代码

 private int mTitleTextColor;
 
 private float mTitleTextSize;
 private String mTitleText;//文字的内容
 
 
 private int img;
 private Bitmap map;
 //bitmap对应的宽高
 private float img_width, img_height;
 Paint paint;
 
 private float numTextWidth;
 //测量seekbar的规格
 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;
 
 private float textCenterX;
 
 private float textbaselineY;
 
 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);//设置抗锯齿
  paint.setTextSize(mTitleTextSize);//设置文字大小
  paint.setColor(mTitleTextColor);//设置文字颜色
  //设置控件的padding 给提示文字留出位置
  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;
 }
 
 
 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();//定位文本绘制的位置
  rect_seek = this.getProgressDrawable().getBounds();
  //定位文字背景图片的位置
  float bm_x = rect_seek.width() * getProgress() / getMax();
  float bm_y = rect_seek.height() + 20;
//  //计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);//画背景图
  // canvas.drawRoundRect();
  canvas.drawText(mTitleText, text_x, (float) (textbaselineY + bm_y + (0.16 * img_height / 2)), paint);//画文字
 
 }
 
 @Override
 public boolean onTouchEvent(MotionEvent event) {
  invalidate();//监听手势滑动，不断重绘文字和背景图的显示位置
  return super.onTouchEvent(event);
 }
 
 
 private void setTextLocation() {
 
  fm = paint.getFontMetrics();
  //文本的宽度
  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;
  }
 }

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持考高分网。