Android实现自由拖动并显示文字的悬浮框

项目中需要实现一个状态显示的悬浮框，要求可以设置两种模式：拖动模式和不可拖动模式。

实现效果图如下：

实现步骤：

1.首先要设置该悬浮框的基本属性：

/**
  * 显示弹出框
  *
  * @param context
  */
 @SuppressWarnings("WrongConstant")
 public static void showPopupWindow(final Context context, String showtxt) {
  if (isShown) {
   return;
  }
  isShown = true;
  // 获取WindowManager
  mWindowManager = (WindowManager) context
    .getSystemService(Context.WINDOW_SERVICE);
  mView = setUpView(context, showtxt);
 
  params = new WindowManager.LayoutParams();
  // 类型，系统提示以及它总是出现在应用程序窗口之上。
  params.type = WindowManager.LayoutParams.TYPE_SYSTEM_ALERT |
    WindowManager.LayoutParams.TYPE_SYSTEM_OVERLAY;
 
  // 设置flag
  int flags = canTouchFlags;
 
  // | WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE;
  // 如果设置了WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE，弹出的View收不到Back键的事件
  params.flags = flags;
  // 不设置这个弹出框的透明遮罩显示为黑色
  params.format = PixelFormat.TRANSLUCENT;
  // FLAG_NOT_TOUCH_MODAL不阻塞事件传递到后面的窗口
  // 设置 FLAG_NOT_FOCUSABLE 悬浮窗口较小时，后面的应用图标由不可长按变为可长按
  // 不设置这个flag的话，home页的划屏会有问题
  params.width = LayoutParams.WRAP_CONTENT;
  params.height = LayoutParams.WRAP_CONTENT;
  params.gravity = Gravity.TOP;
  mWindowManager.addView(mView, params);
}

比较重要的点是要注意设置flags，我这里提供了两种flags以供切换：

private static int canTouchFlags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
   | WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL;
 
 private static int notTouchFlags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE|
   WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE;

第一种是可触摸不可聚焦模式，第二种是不可触摸不可聚焦模式。其他的flags可以从api中查阅。

2.设置悬浮框的拖动监听事件：

private static View setUpView(final Context context, String showtxt) {
  View view = LayoutInflater.from(context).inflate(R.layout.layout_popwindow,
    null);
 
  TextView showTv = (TextView) view.findViewById(R.id.tv_showinpop);
  showTv.setText(showtxt);
 
  rl_drag_showinpop = (RelativeLayout) view.findViewById(R.id.rl_drag_showinpop);
  rl_drag_showinpop.setOnTouchListener(new View.OnTouchListener() {
   private float lastX; //上一次位置的X.Y坐标
   private float lastY;
   private float nowX; //当前移动位置的X.Y坐标
   private float nowY;
   private float tranX; //悬浮窗移动位置的相对值
   private float tranY;
 
   @Override
   public boolean onTouch(View v, MotionEvent event) {
    boolean ret = false;
    switch (event.getAction()) {
     case MotionEvent.ACTION_DOWN:
 
      // 获取按下时的X，Y坐标
      lastX = event.getRawX();
      lastY = event.getRawY();
      ret = true;
 
      break;
     case MotionEvent.ACTION_MOVE:
      // 获取移动时的X，Y坐标
      nowX = event.getRawX();
      nowY = event.getRawY();
      // 计算XY坐标偏移量
      tranX = nowX - lastX;
      tranY = nowY - lastY;
      params.x += tranX;
      params.y += tranY;
 
      //更新悬浮窗位置
      mWindowManager.updateViewLayout(mView, params);
      //记录当前坐标作为下一次计算的上一次移动的位置坐标
      lastX = nowX;
      lastY = nowY;
 
      break;
     case MotionEvent.ACTION_UP:
      break;
    }
    return ret;
   }
});

这里要在down的时候记录坐标，move事件中使用修改params坐标进行移动。

3.设置悬浮框文字属性：

public static void setShowTxt(String txt) {
  try {
   TextView showTv = (TextView) mView.findViewById(R.id.tv_showinpop);
   showTv.setText(txt);
   mWindowManager.updateViewLayout(mView, params);
  }catch (Exception e){
   Log.d(TAG, "setShowTxt: 更新悬浮框错误");
   e.printStackTrace();
   if(e.getMessage().contains("not attached to window manager")){
    mWindowManager.addView(mView, params);
   }
  }
}

4.更新悬浮框图片显示：

public static void setShowImg(Bitmap bitmap) {
  try {
   ImageView showImg = (ImageView) mView.findViewById(R.id.iv_showinpop);
   showImg.setImageBitmap(bitmap);
   mWindowManager.updateViewLayout(mView, params);
  }catch (Exception e){
   Log.d(TAG, "setShowTxt: 更新悬浮框错误");
   e.printStackTrace();
   if(e.getMessage().contains("not attached to window manager")){
    mWindowManager.addView(mView, params);
   }
  }
 }

介绍完毕，整个类都封装好了，代码如下：

/**
 * 悬浮窗工具类
 * created by Pumpkin at 17/3/28
 */
public class WindowsUitlity {
 private static String TAG = WindowsUitlity.class.getSimpleName();
 private static WindowManager mWindowManager = null;
 private static WindowManager.LayoutParams params;
 public static Boolean isShown = false;
 private static View mView = null;
 
 /**
  * 显示弹出框
  *
  * @param context
  */
 @SuppressWarnings("WrongConstant")
 public static void showPopupWindow(final Context context, String showtxt) {
  if (isShown) {
   return;
  }
  isShown = true;
  // 获取WindowManager
  mWindowManager = (WindowManager) context
    .getSystemService(Context.WINDOW_SERVICE);
  mView = setUpView(context, showtxt);
 
  params = new WindowManager.LayoutParams();
  // 类型，系统提示以及它总是出现在应用程序窗口之上。
  params.type = WindowManager.LayoutParams.TYPE_SYSTEM_ALERT |
    WindowManager.LayoutParams.TYPE_SYSTEM_OVERLAY;
 
  // 设置flag
  int flags = canTouchFlags;
 
  // | WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE;
  // 如果设置了WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE，弹出的View收不到Back键的事件
  params.flags = flags;
  // 不设置这个弹出框的透明遮罩显示为黑色
  params.format = PixelFormat.TRANSLUCENT;
  // FLAG_NOT_TOUCH_MODAL不阻塞事件传递到后面的窗口
  // 设置 FLAG_NOT_FOCUSABLE 悬浮窗口较小时，后面的应用图标由不可长按变为可长按
  // 不设置这个flag的话，home页的划屏会有问题
  params.width = LayoutParams.WRAP_CONTENT;
  params.height = LayoutParams.WRAP_CONTENT;
  params.gravity = Gravity.TOP;
  mWindowManager.addView(mView, params);
 }
 
 
 private static int canTouchFlags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
   | WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL;
 
 private static int notTouchFlags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE|
   WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE;
 
 
 /**
  * 设置是否可响应点击事件
  *
  * @param isTouchable
  */
 public static void setTouchable(boolean isTouchable) {
  if (isTouchable) {
   params.flags = canTouchFlags;
  } else {
   params.flags = notTouchFlags;
  }
  mWindowManager.updateViewLayout(mView, params);
 
 }
 
 
 /**
  * 隐藏弹出框
  */
 public static void hidePopupWindow() {
  if (isShown && null != mView) {
   mWindowManager.removeView(mView);
   isShown = false;
  }
 }
 
 public static void setShowTxt(String txt) {
  try {
   TextView showTv = (TextView) mView.findViewById(R.id.tv_showinpop);
   showTv.setText(txt);
   mWindowManager.updateViewLayout(mView, params);
  }catch (Exception e){
   Log.d(TAG, "setShowTxt: 更新悬浮框错误");
   e.printStackTrace();
   if(e.getMessage().contains("not attached to window manager")){
    mWindowManager.addView(mView, params);
   }
  }
 }
 
 
 public static void setShowImg(Bitmap bitmap) {
  try {
   ImageView showImg = (ImageView) mView.findViewById(R.id.iv_showinpop);
   showImg.setImageBitmap(bitmap);
   mWindowManager.updateViewLayout(mView, params);
  }catch (Exception e){
   Log.d(TAG, "setShowTxt: 更新悬浮框错误");
   e.printStackTrace();
   if(e.getMessage().contains("not attached to window manager")){
    mWindowManager.addView(mView, params);
   }
  }
 }
 
 static RelativeLayout rl_drag_showinpop;
 
 private static View setUpView(final Context context, String showtxt) {
  View view = LayoutInflater.from(context).inflate(R.layout.layout_popwindow,
    null);
 
  TextView showTv = (TextView) view.findViewById(R.id.tv_showinpop);
  showTv.setText(showtxt);
 
  rl_drag_showinpop = (RelativeLayout) view.findViewById(R.id.rl_drag_showinpop);
  rl_drag_showinpop.setOnTouchListener(new View.OnTouchListener() {
   private float lastX; //上一次位置的X.Y坐标
   private float lastY;
   private float nowX; //当前移动位置的X.Y坐标
   private float nowY;
   private float tranX; //悬浮窗移动位置的相对值
   private float tranY;
 
   @Override
   public boolean onTouch(View v, MotionEvent event) {
    boolean ret = false;
    switch (event.getAction()) {
     case MotionEvent.ACTION_DOWN:
 
      // 获取按下时的X，Y坐标
      lastX = event.getRawX();
      lastY = event.getRawY();
      ret = true;
 
      break;
     case MotionEvent.ACTION_MOVE:
      // 获取移动时的X，Y坐标
      nowX = event.getRawX();
      nowY = event.getRawY();
      // 计算XY坐标偏移量
      tranX = nowX - lastX;
      tranY = nowY - lastY;
      params.x += tranX;
      params.y += tranY;
 
      //更新悬浮窗位置
      mWindowManager.updateViewLayout(mView, params);
      //记录当前坐标作为下一次计算的上一次移动的位置坐标
      lastX = nowX;
      lastY = nowY;
 
      break;
     case MotionEvent.ACTION_UP:
      break;
    }
    return ret;
   }
  });
 
  return view;
 }
}

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脚本之家。