Android自定义TipView仿QQ长按后的提示窗口

自定义view--TipView

TipView其实就是类似QQ长按消息弹出来的横放的提示框。

通过看书和参考各位大神的博客（再次对大神表示恭敬），我用了一下午时间写完了这么一个view。

先来看图：

1 自定义TipView思路

1 首先我们考虑是继承View还是ViewGroup

其实TipView直观看更像是一个group，里面有子view。但其实我们并不需要继承ViewGroup，因为我们不用像LinearLayout那样在布局文件里面去添加子view，而且TipView的item我们用文字就好。如果继承于Group我们还要考虑onLayout的问题，为了简单我直接继承自View。

2 重写方法

TipView要像PopupWindow、Dialog一样显示在Activity上而不是添加到父容器中，原因是如果创建后添加到父容器中去托管的话，父容器的布局规则会影响我们TipView的显示效果。所以我们要使用WindowManager来把TipView添加到外层布局，并且要充满屏幕，i原因为我们要点击tem之外的地方使TipView消失。所以view大小是固定充满屏幕的，不需要重写onMeasure。
需要重写onDraw来绘制view。

3 显示位置

TipView主要分两部分，一部分是三角标，一部分是带有圆角的主体。

当我们点击后，三角标顶点始终在点击位置上方一定距离（如果顶点定位在点击位置，会导致手指挡住一部分三角，用户体验度不佳），并且主体不要与屏幕左右边界碰撞，当要遮挡ToolBar时向下绘制。

2 定义变量

public static final int TOP = 0;//从点击位置上面绘制
  public static final int DOWN = 1;//...下面...

  private int mItemWidth;//item宽
  private int mItemHeight;//item高
  private int mTriaHeight;//三角的高度
  private int mHalfTriaWidth;//三角的半宽
  private int mTriaAcme;//三角的顶点
  private int mTriaItemBorder;//三角的顶点
  private int realLeft;//窗口距左边的值
  private int marginSide;//窗口距左右边的值,防止出现的窗口紧贴边界
  private int mSeparateLineColor = Color.WHITE;
  private int mTextSize;//选项文字的大小
  private int mTextColor;//选项文字的颜色

  private int mItemSeparation;//分割线宽度;
  private int mRadius;//圆角
  private List<TextItem> items;//存放item的集合
  private List<Rect> mItemRectList = new ArrayList<>(); // 存储每个方块
  private Paint mPaint;//画笔
  private Paint mSeparationPaint;//分割线画笔
  private Paint mSPaint;//三角的画笔
  private Path mPath;//路径
  private int x, y;//点击的位置
  private ViewGroup viewRoot;//父容器
  private int location = TOP;//绘制位置
  private int choose = -1;//点击的item
  private int mToolbarBottom;//Toolbar下边距屏幕上距离
  private WindowManager windowManager;
  private WindowManager.LayoutParams layoutParams;//windowManger布局管理器,为了像Dialog一样在Activity弹出，而不是依附于某个group
  private onItemCilckLinener itemCilckLinener;
  private Context context = null;

3 构造函数以及初始化方法

private MyTipView(Context context, int x, int y, ViewGroup viewRoot, List<TextItem> items) {
    super(context);
    this.viewRoot = viewRoot;
    this.context = context;
    this.x = x;
    this.y = y;
    this.items = items;
    windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
    layoutParams = new WindowManager.LayoutParams();
    layoutParams.width = WindowManager.LayoutParams.MATCH_PARENT;//窗口的宽
    layoutParams.height = WindowManager.LayoutParams.MATCH_PARENT;//窗口的高
    //设置LayoutParams的属性
    layoutParams.type = WindowManager.LayoutParams.TYPE_APPLICATION_PANEL;//该Type描述的是形成的窗口的层级关系，下面会详细列出它的属性
    layoutParams.format = PixelFormat.TRANSLUCENT;//不设置这个弹出框的透明遮罩显示为黑色
    //layoutParams.token = viewRoot.getWindowToken();//设置Token
    int[] location = new int[2];
    viewRoot.getLocationInWindow(location);//获取在当前窗口内的绝对坐标
    viewRoot.getLocationOnScreen(location);//获取在整个屏幕内的绝对坐标
    mToolbarBottom = location[1];//[0]是x轴坐标，[1]y轴
    windowManager.addView(this, layoutParams);
    init();
    initView();
  }

  //初始化画笔
  private void init() {
    mPaint = new Paint();
    mSPaint = new Paint();
    mPath = new Path();
    mSeparationPaint = new Paint();
    mSeparationPaint.setStyle(Paint.Style.FILL);
    mPaint.setAntiAlias(true);
    mPaint.setStyle(Paint.Style.FILL);
    mPaint.setTextSize(Sp2Px(14));
    mPaint.setColor(Color.BLACK);
    mSPaint.setAntiAlias(true);
    mSPaint.setStyle(Paint.Style.FILL);
    mSPaint.setColor(Color.BLACK);
    //初始变量
    mItemWidth = Dp2Px(50);
    mItemHeight = Dp2Px(48);
    mTriaHeight = Dp2Px(10);//三角的高度
    mHalfTriaWidth = Dp2Px(6);//三角的半宽
    mTriaAcme = Dp2Px(6);//三角的顶点
    marginSide = Dp2Px(4);//左右边距
    mItemSeparation = Dp2Px(1);//分割线宽度;
    mRadius = Dp2Px(6);//圆角
    mTextColor = Color.WHITE;
    mTextSize = Sp2Px(14);
  }

4 计算三角顶点位置

private void initView() {
    int count = items.size();
    int width = count * mItemWidth + mItemSeparation * (count - 1);
    int mScreenWidth = getResources().getDisplayMetrics().widthPixels;
    if (y - mToolbarBottom < (mItemHeight + mTriaHeight + mTriaAcme)) {
      location = DOWN;//下方显示
      mTriaAcme += y;//设置三角顶点y轴值；
      mTriaItemBorder = mTriaAcme + mTriaHeight;//计算三角方块交界y
    } else {
      location = TOP;
      mTriaAcme = y - mTriaAcme;//计算顶点位置y轴值
      mTriaItemBorder = mTriaAcme - mTriaHeight;//计算三角方块交界y值
    }
    if (x < (width / 2 + marginSide)) {
      realLeft = marginSide;//计算最左侧距离屏幕左边距离，左边撑不下
    } else if ((mScreenWidth - x) < (width / 2 + marginSide)) {
      realLeft = mScreenWidth - marginSide - width;//计算最左侧距离屏幕左边距离，右边撑不下
    } else {
      realLeft = x - width / 2;//计算最左侧距离屏幕左边距离，触碰不到边界
    }
  }

5 设置背景为透明

private void drawBackground(Canvas canvas) {
    canvas.drawColor(Color.TRANSPARENT);
  }

6 绘制三角

private void drawTop(Canvas canvas) {
    //绘制三角
    mPath.reset();
    mPath.moveTo(x, mTriaAcme);
    mPath.lineTo(x - mHalfTriaWidth, mTriaAcme - mTriaHeight);
    mPath.lineTo(x + mHalfTriaWidth, mTriaAcme - mTriaHeight);
    canvas.drawPath(mPath, mSPaint);
    MyDraw(canvas, mTriaItemBorder - mItemHeight);
  }

  private void drawDown(Canvas canvas) {
    //绘制三角
    mPath.reset();//清理路径
    mPath.moveTo(x, mTriaAcme);
    mPath.lineTo(x - mHalfTriaWidth, mTriaAcme + mTriaHeight);
    mPath.lineTo(x + mHalfTriaWidth, mTriaAcme + mTriaHeight);
    canvas.drawPath(mPath, mSPaint);
    //绘制方块
    MyDraw(canvas, mTriaItemBorder);
  }

7 绘制方块

绘制时因为第一个和最后一个方块带有圆角，单独绘制

private void MyDraw(Canvas canvas, int t) {
    //绘制item
    int count = items.size();
    int width = (count - 1) * mItemSeparation + count * mItemWidth;
    int l = realLeft + mItemWidth + mItemSeparation;
    mItemRectList.clear();
    for (int i = 0; i < items.size(); i++) {
      if (choose == i) {//当前是否被点击，改变颜色
        mPaint.setColor(Color.DKGRAY);
      } else {
        mPaint.setColor(Color.BLACK);
      }
      if (i == 0) {//绘制第一个带圆角的item
        mPath.reset();
        mPath.moveTo(realLeft + mItemWidth, t);
        mPath.lineTo(realLeft + mRadius, t);
        mPath.quadTo(realLeft, t, realLeft, t + mRadius);
        mPath.lineTo(realLeft, t + mItemHeight - mRadius);
        mPath.quadTo(realLeft, t + mItemHeight, realLeft + mRadius, mItemHeight + t);
        mPath.lineTo(realLeft + mItemWidth, t + mItemHeight);
        canvas.drawPath(mPath, mPaint);
        mSeparationPaint.setColor(mSeparateLineColor);
        canvas.drawLine(realLeft + mItemWidth, t, realLeft + mItemWidth,
            t + mItemHeight, mSeparationPaint);
      } else if (i == (items.size() - 1)) {//绘制最后一个
        mPath.reset();
        mPath.rMoveTo(realLeft + width - mItemWidth, t);
        mPath.lineTo(realLeft + width - mRadius, t);
        mPath.quadTo(realLeft + width, t, realLeft + width, t + mRadius);
        mPath.lineTo(realLeft + width, t + mItemHeight - mRadius);
        mPath.quadTo(realLeft + width, t + mItemHeight, realLeft + width - mRadius, t + mItemHeight);
        mPath.lineTo(realLeft + width - mItemWidth, t + mItemHeight);
        canvas.drawPath(mPath, mPaint);
      } else {//绘制中间方块和分割线
        mPath.reset();
        mPath.moveTo(l, t);
        mPath.lineTo(l + mItemWidth, t);
        mPath.lineTo(l + mItemWidth, t + mItemHeight);
        mPath.lineTo(l, t + mItemHeight);
        canvas.drawPath(mPath, mPaint);
        canvas.drawLine(l + mItemWidth, t, l + mItemWidth, t + mItemHeight,
            mSeparationPaint);
        l += mItemWidth + mItemSeparation;
      }
      mItemRectList.add(new Rect(realLeft + i * (mItemSeparation + mItemWidth), t, realLeft + i * (mItemSeparation + mItemWidth) + mItemWidth, t + mItemHeight));
    }
  }

最后一行代码

代码如下:

mItemRectList.add(new Rect(realLeft + i * (mItemSeparation + mItemWidth), t, realLeft + i * (mItemSeparation + mItemWidth) + mItemWidth, t + mItemHeight));

用一个List来存放Rect（矩形），这些矩形对应的是每一个item的方块，但是并没有绘制出来，只是存放起来，矩形是为了在绘制文字的时候提供文字居中时用到的。

8 绘制文字

private void drawTitle(Canvas canvas) {
    for (int i = 0; i < items.size(); i++) {
      Rect rect = mItemRectList.get(i);//用于文字居中
      //mPaint.setColor(Color.WHITE);
      Paint p = new Paint(Paint.ANTI_ALIAS_FLAG);
      p.setAntiAlias(true);
      p.setStrokeWidth(3);
      int s = Dp2Px(items.get(i).getTextSize());
      p.setTextSize(mTextSize);
      if (s != 0)//如果在TextItem中设置了size，就是用设置的size
        p.setTextSize(s);
      p.setColor(mTextColor);
      Paint.FontMetricsInt fontMetricsInt = p.getFontMetricsInt();
      p.setTextAlign(Paint.Align.CENTER);
      int baseline = (rect.bottom + rect.top - fontMetricsInt.bottom - fontMetricsInt.top) / 2;//文字居中，基线算法
      canvas.drawText(items.get(i).getTitle(), rect.centerX(), baseline, p);
    }
  }

9 点击变色，以及点击事件实现

@Override
  public boolean onTouchEvent(MotionEvent event) {
    switch (event.getAction()) {
      case MotionEvent.ACTION_DOWN:
        for (int i = 0; i < items.size(); i++) {
          if (itemCilckLinener != null && isPointInRect(new PointF(event.getX(), event.getY()), mItemRectList.get(i))) {
            choose = i;//记录点击item编号
            Rect rect = mItemRectList.get(i);
            postInvalidate(rect.left, rect.top, rect.right, rect.bottom);//刷新视图
            return true;
          }
        }
        removeView();//点击item以外移除
        return false;
      case MotionEvent.ACTION_UP:
        for (int i = 0; i < items.size(); i++) {
          if (itemCilckLinener != null && isPointInRect(new PointF(event.getX(), event.getY()), mItemRectList.get(i))) {
            if (i == choose) {//与down的item一样时才触发
              itemCilckLinener.onItemCilck(items.get(i).getTitle(), i);//触发点击事件
              removeView();
              return true;
            }
          } else {//点下后移动出item，初始化视图
            postInvalidate();//刷新视图
          }
        }
        choose = -1;//重置
        return false;
    }
    return false;
  }
 /**
   * 判断这个点有没有在矩形内
   *
   * @param pointF
   * @param targetRect
   * @return
   */
  private boolean isPointInRect(PointF pointF, Rect targetRect) {
    if (pointF.x < targetRect.left) {
      return false;
    }
    if (pointF.x > targetRect.right) {
      return false;
    }
    if (pointF.y < targetRect.top) {
      return false;
    }
    if (pointF.y > targetRect.bottom) {
      return false;
    }
    return true;
  }

10 Builder模式创建

public static class Builder {
    private List<TextItem> items = new ArrayList<>();
    private int x = 0, y = 0;
    private Context context;
    private ViewGroup viewRoot;
    private onItemCilckLinener itemCilckLinener;
    private int mRadius;

    public Builder(Context context, ViewGroup viewRoot) {
      this.context = context;
      this.viewRoot = viewRoot;
    }
    public Builder addItem(TextItem item) {
      items.add(item);
      return this;
    }
    public Builder setmRadius(int radius) {
      mRadius = radius;
      return this;
    }
    public Builder setxAndy(int x, int y) {
      this.x = x;
      this.y = y;
      return this;
    }
    public Builder setOnItemClickLinener(onItemCilckLinener itemClickLinener) {
      this.itemCilckLinener = itemClickLinener;
      return this;
    }
    public MyTipView create() {
      if (items.size() == 0) {
        try {
          throw new Exception("item count is 0");
        } catch (Exception e) {
          e.printStackTrace();
        }
      }
      MyTipView myTipView = new MyTipView(context, x, y, viewRoot, items);
      myTipView.setItemCilckLinener(itemCilckLinener);
      if (mRadius != 0)
        myTipView.setRadius(mRadius);
      return myTipView;
    }
  }

11 item

//TipView的item
  public static class TextItem {
    private String title;
    private int textSize;
    private int textColor = Color.WHITE;

    public TextItem(String title) {
      this.title = title;
    }
    public TextItem(String title, int textSize) {
      this.title = title;
      this.textSize = textSize;
    }
    public TextItem(String title, int textSize, int textColor) {
      this.title = title;
      this.textSize = textSize;
      this.textColor = textColor;
    }
    public String getTitle() {
      return title;
    }
    public void setTitle(String title) {
      this.title = title;
    }
    public int getTextSize() {
      return textSize;
    }
    public void setTextSize(int textSize) {
      this.textSize = textSize;
    }
    public int getTextColor() {
      return textColor;
    }
    public void setTextColor(int textColor) {
      this.textColor = textColor;
    }
  }

12 使用示例

MyTipView.Builder builder = new MyTipView.Builder(this, linearLayout);
    builder.addItem(new MyTipView.TextItem("1"))
        .addItem(new MyTipView.TextItem("2"))
        .addItem(new MyTipView.TextItem("3"))
        .addItem(new MyTipView.TextItem("4"))
        .setxAndy((int) x, (int) y)
        .setOnItemClickLinener(new MyTipView.onItemCilckLinener() {
          @Override
          public void onItemCilck(String title, int i) {
            Toast.makeText(MainActivity.this, title, Toast.LENGTH_SHORT).show();
          }
        })
        .create();

13 源码

https://github.com/liujiakuoyx/learn/blob/master/MyTipView.java

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我们。