Android实现系统级悬浮按钮

import android.content.Context;import android.graphics.Canvas;import android.graphics.Point;import android.graphics.Rect;import android.util.AttributeSet;import android.view.MotionEvent;import android.view.View;import android.view.WindowManager;import android.widget.ImageView;import com.iapppay.openid.channel.LoginResultCallback;import com.iapppay.openid.channel.OpenIDApplication;import com.iapppay.openid.channel.util.DisplayUtil;import com.iapppay.openid.channel.util.LogUtil;import com.iapppay.openid.channel.util.Res;/** * Created by HuangTiebing 2017/2/14. */public class DragFloatActionButton extends ImageView implements View.OnTouchListener, View.OnClickListener {  public static String TAG = "DragFloatActionButton";  private Context context;  float lastX, lastY;  float originX, originY;  int screenWidth;  int screenHeight;  private int originWidth;  private WindowManager windowManager;  //  // 此windowManagerParams变量为获取的全局变量，用以保存悬浮窗口的属性  private WindowManager.LayoutParams windowManagerParams;  private LoginResultCallback resultCallback; //悬浮按钮点击回调  public DragFloatActionButton(Context context, boolean isForceLogin, LoginResultCallback resultCallback) {    this(context, null);    OpenIDApplication.getInstance().setForceLogin(isForceLogin);    this.resultCallback = resultCallback;  }  public DragFloatActionButton(Context context, AttributeSet attrs) {    this(context, attrs, 0);  }  public DragFloatActionButton(Context context, AttributeSet attrs, int defStyleAttr) {    super(context, attrs, defStyleAttr);    this.context = context;    Point screenSize = DisplayUtil.getScreenSize(context);    screenWidth = screenSize.x;    screenHeight = screenSize.y;    setImageResource(Res.drawable(context, "ipay_float_btn_bg"));    setOnTouchListener(this);    setOnClickListener(this);    windowManager = (WindowManager) getContext().getApplicationContext().getSystemService(Context.WINDOW_SERVICE);  }  public int getOriginWidth() {    return originWidth;  }  public void setOriginWidth(int originWidth) {    this.originWidth = originWidth;  }  @Override  public boolean onTouch(View v, MotionEvent event) {    windowManagerParams = (WindowManager.LayoutParams) this.getLayoutParams();    //获取到状态栏的高度    Rect frame = new Rect();    getWindowVisibleDisplayFrame(frame);    int ea = event.getAction();    switch (ea) {      case MotionEvent.ACTION_DOWN:        lastX = event.getRawX();// 获取触摸事件触摸位置的原始X坐标        lastY = event.getRawY();        originX = lastX;        originY = lastY;        break;      case MotionEvent.ACTION_MOVE:        float dx = event.getRawX() - lastX;        float dy = event.getRawY() - lastY;        windowManagerParams.x += dx;        windowManagerParams.y += dy;        LogUtil.d(TAG, "移动距离：dx=" + dx + "，dy=" + dy);        showAllBtn();        lastX = (int) event.getRawX();        lastY = (int) event.getRawY();        break;      case MotionEvent.ACTION_UP:        float lastMoveDx = Math.abs(event.getRawX() - originX);        float lastMoveDy = Math.abs(event.getRawY() - originY);        LogUtil.d(TAG, "松开时，移动距离：lastMoveDx=" + lastMoveDx + ", lastMoveDy=" + lastMoveDy);        if (lastMoveDx < 10 && lastMoveDy < 10) { //移动距离太小，视为点击，          return false;        } else {          updateViewLayout(event);          isFirstClick = true;          return true;        }    }    return false;  }  /**   * 显示整个图标   */  public void showAllBtn() {    windowManagerParams.width = originWidth;    windowManagerParams.height = originWidth;    setImageResource(Res.drawable(context, "ipay_float_btn_bg"));    windowManager.updateViewLayout(this, windowManagerParams); // 刷新显示  }  /**   * 悬浮按钮显示在左边   */  private void showInLeft() {    windowManagerParams.x = 0;    windowManagerParams.width = originWidth / 2;    windowManagerParams.height = originWidth;    setImageResource(Res.drawable(context, "ipay_float_btn_left_hidden"));    windowManager.updateViewLayout(this, windowManagerParams); // 刷新显示  }  /**   * 悬浮按钮显示在右边   */  private void showInRight() {    windowManagerParams.width = originWidth / 2;    windowManagerParams.height = originWidth;    windowManagerParams.x = screenWidth - windowManagerParams.width;    setImageResource(Res.drawable(context, "ipay_float_btn_right_hidden"));    windowManager.updateViewLayout(this, windowManagerParams); // 刷新显示  }  /**   * 悬浮按钮显示在上面   */  private void showInTop() {    windowManagerParams.y = 0;    windowManagerParams.width = originWidth;    windowManagerParams.height = originWidth / 2;    setImageResource(Res.drawable(context, "ipay_float_btn_top_hidden"));    windowManager.updateViewLayout(this, windowManagerParams); // 刷新显示  }  /**   * 悬浮按钮显示在下面   */  private void showInBottom() {    windowManagerParams.width = originWidth;    windowManagerParams.height = originWidth / 2;    windowManagerParams.y = screenHeight - windowManagerParams.width;    setImageResource(Res.drawable(context, "ipay_float_btn_bottom_hidden"));    windowManager.updateViewLayout(this, windowManagerParams); // 刷新显示  }  /**   * 更新悬浮图标   *   * @param event 手动移动事件   */  public void updateViewLayout(MotionEvent event) {    Point center = new Point(screenWidth / 2, screenHeight / 2); //屏幕中心点    float xOffset, yOffset;//以屏幕中心点为原点，X轴和Y轴上的偏移量    if (event != null) {//手动移动的      xOffset = event.getRawX() - center.x;      yOffset = event.getRawY() - center.y;    } else {//自动隐藏      xOffset = lastX - center.x;      yOffset = lastY - center.y;    }    if (Math.abs(xOffset) >= Math.abs(yOffset)) {//向左或向右缩进隐藏      if (xOffset <= 0) { //向左缩进        showInLeft();      } else {        showInRight();      }    } else {//向上或向下缩进隐藏      if (yOffset <= 0) {//向上缩进        showInTop();      } else {        showInBottom();      }    }  }  @Override  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {    super.onMeasure(widthMeasureSpec, heightMeasureSpec);  }  @Override  protected void onLayout(boolean changed, int left, int top, int right, int bottom) {    super.onLayout(changed, left, top, right, bottom);    Point screenSize = DisplayUtil.getScreenSize(context);    if (screenWidth != screenSize.x) {//屏幕旋转切换      screenWidth = screenSize.x;      screenHeight = screenSize.y;      lastY = windowManagerParams.x;      lastX = windowManagerParams.y;      windowManagerParams.x = (int) lastX;      windowManagerParams.y = (int) lastY;      updateViewLayout(null);    }  }  private boolean isFirstClick = true;  @Override  protected void onDraw(Canvas canvas) {    super.onDraw(canvas);  }  @Override  public void onClick(View v) {    LogUtil.d(TAG, "执行点击事件");    if (!isFirstClick) {      OpenIDApplication.getInstance().floatBtnClick(context, OpenIDApplication.getInstance().isForceLogin(), resultCallback);    } else {//半隐藏状态，点击显示全部      isFirstClick = false;      showAllBtn();    }  }}

WindowManager.LayoutParams windowManagerParams = new WindowManager.LayoutParams(WindowManager.LayoutParams.TYPE_TOAST, WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL | WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE, PixelFormat.TRANSLUCENT);

DragFloatActionButton floatBtn = new DragFloatActionButton(context, isForceLogin, mResultCallback);   WindowManager windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);   // 设置LayoutParams(全局变量）相关参数   WindowManager.LayoutParams windowManagerParams = new WindowManager.LayoutParams(WindowManager.LayoutParams.TYPE_TOAST,     WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL | WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE,     PixelFormat.TRANSLUCENT);   /**    * 注意，flag的值可以为：    * 下面的flags属性的效果形同“锁定”。    * 悬浮窗不可触摸，不接受任何事件,同时不影响后面的事件响应。    * LayoutParams.FLAG_NOT_TOUCH_MODAL 不影响后面的事件    * LayoutParams.FLAG_NOT_FOCUSABLE 不可聚焦    * LayoutParams.FLAG_NOT_TOUCHABLE 不可触摸    */   // 调整悬浮窗口至左上角，便于调整坐标   windowManagerParams.gravity = Gravity.LEFT | Gravity.TOP;   // 以屏幕左上角为原点，设置x、y初始值   windowManagerParams.x = 0;   windowManagerParams.y = 0;   // 设置悬浮窗口长宽数据   floatBtn.measure(0, 0);   floatBtn.setOriginWidth(floatBtn.getMeasuredWidth() - 50);   windowManagerParams.width = floatBtn.getOriginWidth();   windowManagerParams.height = windowManagerParams.width;   // 显示myFloatView图像   windowManager.addView(floatBtn, windowManagerParams);