Android 自定义星评空间示例代码

没事做用自定义view方式写一个星评控件，虽说网上很多这个控件，但是这是自己写的，在这里记录一下。

首先需要自定义属性

<declare-styleable name="Rate">
    <!--属性分别是：单个的宽，高，之间的距离，激活的数量，总数量，激活的drawable，没有激活的drawable，是否可以选择数量-->
    <attr name="custom_rate_width" format="dimension"/>
    <attr name="custom_rate_height" format="dimension"/>
    <attr name="custom_rate_padding" format="dimension"/>
    <attr name="custom_rate_active_size" format="integer"/>
    <attr name="custom_rate_size" format="integer"/>
    <attr name="custom_rate_active_drawable" format="reference"/>
    <attr name="custom_rate_disactive_drawable" format="reference"/>
    <attr name="custom_rate_touch" format="boolean"/>
  </declare-styleable>

初始化代码

 protected void init(Context context, AttributeSet attrs) {
    TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.Rate);
    int activeId = 0;
    int disactiveId = 0;
    if (array != null) {
      size = array.getInt(R.styleable.Rate_custom_rate_size, 5);
      activeSize = array.getInt(R.styleable.Rate_custom_rate_active_size, 3);
      rateWidth = array.getDimensionPixelOffset(R.styleable.Rate_custom_rate_width, 0);
      rateHeight = array.getDimensionPixelOffset(R.styleable.Rate_custom_rate_height, 0);
      activeId = array.getResourceId(R.styleable.Rate_custom_rate_active_drawable, 0);
      disactiveId = array.getResourceId(R.styleable.Rate_custom_rate_disactive_drawable, 0);
      padding = array.getDimensionPixelOffset(R.styleable.Rate_custom_rate_padding, 0);
      isTouch = array.getBoolean(R.styleable.Rate_custom_rate_touch, false);
      array.recycle();
    }
    //如果没有宽高就设置一个默认值
    if (rateHeight <= 0){
      rateHeight = 80;
    }
    if (rateWidth <= 0){
      rateWidth = 80;
    }
    if (activeId!=0){
      activeBitmap = BitmapFactory.decodeResource(getResources(), activeId);
      //如果没有设置宽高时候
      if (rateWidth <= 0) {
        rateWidth = activeBitmap.getWidth();
      }
      //把图片压缩到设置的宽高
      activeBitmap = Bitmap.createScaledBitmap(activeBitmap, (int) rateWidth, (int) rateHeight, false);
    }
    if (disactiveId != 0){
      disactiveBitmap = BitmapFactory.decodeResource(getResources(), disactiveId);
      if (rateHeight <= 0) {
        rateHeight = activeBitmap.getHeight();
      }
      disactiveBitmap = Bitmap.createScaledBitmap(disactiveBitmap, (int) rateWidth, (int) rateHeight, false);
    }
    mPaint = new Paint();//初始化bitmap的画笔
    mPaint.setAntiAlias(true);
    activPaint = new Paint();//初始化选中星星的画笔
    activPaint.setAntiAlias(true);
    activPaint.setColor(Color.YELLOW);
    disactivPaint = new Paint();//初始化未选中星星的画笔
    disactivPaint.setAntiAlias(true);
    disactivPaint.setColor(Color.GRAY);
  }

onMeasure方法设置View的宽高，如果设置的每一个星星控件的宽高大于实际view的宽高，就用星星空间的宽高作于view的宽高

@Override
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    int widthMode = MeasureSpec.getMode(widthMeasureSpec);
    int widthSize = MeasureSpec.getSize(widthMeasureSpec);
    int heightMode = MeasureSpec.getMode(heightMeasureSpec);
    int heightSize = MeasureSpec.getSize(heightMeasureSpec);
    //计算宽
    if (widthMode == MeasureSpec.EXACTLY) {
      //如果view的宽度小于设置size*星星的宽度，就用size * (int) (padding + rateWidth)做为控件的宽度度
      if (widthSize < size * (int) (padding + rateWidth)) {
        width = size * (int) (padding + rateWidth);
      } else {
        width = widthSize;
      }
    } else {
      width = size * (int) (padding + rateWidth)-padding;
    }
    //计算高
    if (heightMode == MeasureSpec.EXACTLY) {
      //如果view的高度小于设置星星的高度，就用星星高度做为控件的高度
      if (heightSize < rateHeight) {
        height = (int) rateHeight + 5;
      } else {
        height = heightSize;
      }
    } else {
      height = (int) rateHeight + 5;
    }
    setMeasuredDimension(width, height);
  }

onDraw方法中绘制

//开始画active
    for (int i = 0; i < activeSize; i++) {
      if (activeBitmap != null){
        if (i == 0) {
          canvas.drawBitmap(activeBitmap, rateWidth * i, (height - rateHeight) / 2, mPaint);
        } else {
          canvas.drawBitmap(activeBitmap, (rateWidth + padding) * i, (height - rateHeight) / 2, mPaint);
        }
      }else {
        drawActivRate(i,canvas);
      }
    }
//    //开始画disactive
    for (int i = activeSize; i < size; i++) {
      if (disactiveBitmap != null){
        if (i == 0) {
          canvas.drawBitmap(disactiveBitmap, rateWidth * i, (height - rateHeight) / 2, mPaint);
        } else {
          canvas.drawBitmap(disactiveBitmap, (rateWidth + padding) * i, (height - rateHeight) / 2, mPaint);
        }
      }else {
        drawDisActivRate(i,canvas);
      }
    }

上面用到两个方法drawActivRate和drawDisActivRate，分别是在没有设置活动中的星星和不在活动中星星的图片的时候，绘制在活动和不在活动的默认星星：

/**
   * 绘制黄色的五角星（在活动的）
   * */
  private void drawActivRate(int position,Canvas canvas){
    float radius = rateWidth/2;//根據每一個星星的位置繪製園，確定五角星五個點的位置
    float angle = 360/5;
    float centerX = (rateWidth+padding)*(position+1)-padding-radius;//獲取每一個星星空間的中心位置的X坐標
    float centerY =height/2;//獲取每一個星星空間的中心位置的y坐標
    Path mPath = new Path();
    mPath.moveTo(centerX,centerY-radius);
    mPath.lineTo(centerX+(float) Math.cos((angle*2-90)*Math.PI / 180)*radius,centerY+(float)Math.sin((angle*2-90)*Math.PI / 180)*radius);
    mPath.lineTo( centerX-(float)Math.sin(angle*Math.PI / 180)*radius,centerY-(float)Math.cos(angle*Math.PI / 180)*radius);
    mPath.lineTo( centerX+(float)Math.sin(angle*Math.PI / 180)*radius,centerY-(float)Math.cos(angle*Math.PI / 180)*radius);
    mPath.lineTo( centerX-(float)Math.sin((angle*3-180)*Math.PI / 180)*radius,centerY+(float)Math.cos((angle*3-180)*Math.PI / 180)*radius);
//    mPath.lineTo(centerX,centerY-radius);
    mPath.close();
    canvas.drawPath(mPath,activPaint);
  }
  /**
   * 绘制灰色的五角星
   * */
  private void drawDisActivRate(int position,Canvas canvas){
    float radius = rateWidth/2;
    float angle = 360/5;
    float centerX = (rateWidth+padding)*(position+1)-padding-radius;
    float centerY =height/2;
    Path mPath = new Path();
    mPath.moveTo(centerX,centerY-radius);
    mPath.lineTo(centerX+(float) Math.cos((angle*2-90)*Math.PI / 180)*radius,centerY+(float)Math.sin((angle*2-90)*Math.PI / 180)*radius);
    mPath.lineTo( centerX-(float)Math.sin(angle*Math.PI / 180)*radius,centerY-(float)Math.cos(angle*Math.PI / 180)*radius);
    mPath.lineTo( centerX+(float)Math.sin(angle*Math.PI / 180)*radius,centerY-(float)Math.cos(angle*Math.PI / 180)*radius);
    mPath.lineTo( centerX-(float)Math.sin((angle*3-180)*Math.PI / 180)*radius,centerY+(float)Math.cos((angle*3-180)*Math.PI / 180)*radius);
//    mPath.lineTo(centerX,centerY-radius);
    mPath.close();
    canvas.drawPath(mPath,disactivPaint);
  }

最后在onTouchEvent方法中处理选中和未选中星星的处理

@Override
  public boolean onTouchEvent(MotionEvent event) {
    if (!isTouch){//如果不支持觸摸
      return false;
    }
    switch (event.getAction()) {
      case MotionEvent.ACTION_DOWN:
        touchX = event.getX();
        touchY = event.getY();
        for (int i = 0; i < size; i++) {
          if (i == 0) {
            if (0.0 < touchX && touchX < rateWidth+padding/2) {
              activeSize = 1;
            }
          }else {
            if ((rateWidth+padding)*i-padding/2<touchX&&touchX<(rateWidth+padding)*(i+1)-padding/2){
              activeSize = i+1;
            }
          }
        }
        invalidate();
        break;
      case MotionEvent.ACTION_UP:
        if ( null!= changeListener){
          changeListener.change(activeSize);
        }
        break;
      case MotionEvent.ACTION_MOVE:
        touchX = event.getX();
        touchY = event.getY();
        for (int i = 0; i < size; i++) {
          if (i == 0) {
            if (0.0 < touchX && touchX < rateWidth+padding/2) {
              activeSize = 1;
            }
          }else {
            if ((rateWidth+padding)*i-padding/2<touchX&&touchX<(rateWidth+padding)*(i+1)-padding/2){
              activeSize = i+1;
            }
          }
        }
        invalidate();
        if (touchX<=0){
          activeSize = 0;
        }
        break;
    }
    return true;
  }

以上就是自定义view写的星评控件，代码中的注解已经比较详细了，就不多说了，

源码地址

以上所述是小编给大家介绍的android自定义星评空间的实例代码，希望对大家有所帮助！