android编程实现悬浮窗体的方法

public class DesktopLayout extends LinearLayout {
  public DesktopLayout(Context context) {
    super(context);
    setOrientation(LinearLayout.VERTICAL);// 水平排列
    //设置宽高
    this.setLayoutParams( new LayoutParams(LayoutParams.WRAP_CONTENT,
        LayoutParams.WRAP_CONTENT));
    View view = LayoutInflater.from(context).inflate( 
        R.layout.desklayout, null); 
    this.addView(view);
  }

// 取得系统窗体
mWindowManager = (WindowManager) getApplicationContext()
    .getSystemService("window");
// 窗体的布局样式
mLayout = new WindowManager.LayoutParams();
// 设置窗体显示类型——TYPE_SYSTEM_ALERT(系统提示)
mLayout.type = WindowManager.LayoutParams.TYPE_SYSTEM_ALERT;
// 设置窗体焦点及触摸：
// FLAG_NOT_FOCUSABLE(不能获得按键输入焦点)
mLayout.flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE;
// 设置显示的模式
mLayout.format = PixelFormat.RGBA_8888;
// 设置对齐的方法
mLayout.gravity = Gravity.TOP | Gravity.LEFT;
// 设置窗体宽度和高度
mLayout.width = WindowManager.LayoutParams.WRAP_CONTENT;
mLayout.height = WindowManager.LayoutParams.WRAP_CONTENT;

package com.yc.yc_suspendingform;
import android.app.Activity;
import android.graphics.PixelFormat;
import android.graphics.Rect;
import android.os.Bundle;
import android.util.Log;
import android.view.Gravity;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnTouchListener;
import android.view.WindowManager;
import android.widget.Button;
import com.yc.yc_floatingform.R;
public class MainActivity extends Activity {
  private WindowManager mWindowManager;
  private WindowManager.LayoutParams mLayout;
  private DesktopLayout mDesktopLayout;
  private long startTime;
  // 声明屏幕的宽高
  float x, y;
  int top;
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);    
    createWindowManager();
    createDesktopLayout();
    Button btn = (Button) findViewById(R.id.btn);
    btn.setOnClickListener(new OnClickListener() {
      public void onClick(View v) {
        showDesk();
      }
    });
  }
  /**
   * 创建悬浮窗体
   */
  private void createDesktopLayout() {
    mDesktopLayout = new DesktopLayout(this);
    mDesktopLayout.setOnTouchListener(new OnTouchListener() {
      float mTouchStartX;
      float mTouchStartY;
      @Override
      public boolean onTouch(View v, MotionEvent event) {
        // 获取相对屏幕的坐标，即以屏幕左上角为原点
        x = event.getRawX();
        y = event.getRawY() - top; // 25是系统状态栏的高度
        Log.i("startP", "startX" + mTouchStartX + "====startY"
            + mTouchStartY);
        switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
          // 获取相对View的坐标，即以此View左上角为原点
          mTouchStartX = event.getX();
          mTouchStartY = event.getY();
          Log.i("startP", "startX" + mTouchStartX + "====startY"
              + mTouchStartY);
          long end = System.currentTimeMillis() - startTime;
          // 双击的间隔在 300ms以下
          if (end <300) {
            closeDesk();
          }
          startTime = System.currentTimeMillis();
          break;
        case MotionEvent.ACTION_MOVE:
          // 更新浮动窗口位置参数
          mLayout.x = (int) (x - mTouchStartX);
          mLayout.y = (int) (y - mTouchStartY);
          mWindowManager.updateViewLayout(v, mLayout);
          break;
        case MotionEvent.ACTION_UP:
          // 更新浮动窗口位置参数
          mLayout.x = (int) (x - mTouchStartX);
          mLayout.y = (int) (y - mTouchStartY);
          mWindowManager.updateViewLayout(v, mLayout);
          // 可以在此记录最后一次的位置
          mTouchStartX = mTouchStartY = 0;
          break;
        }
        return true;
      }
    });
  }
  @Override
  public void onWindowFocusChanged(boolean hasFocus) {
    super.onWindowFocusChanged(hasFocus);
    Rect rect = new Rect();
    // /取得整个视图部分,注意，如果你要设置标题样式，这个必须出现在标题样式之后，否则会出错
    getWindow().getDecorView().getWindowVisibleDisplayFrame(rect);
    top = rect.top;//状态栏的高度，所以rect.height,rect.width分别是系统的高度的宽度
    Log.i("top",""+top);
  }
  /**
   * 显示DesktopLayout
   */
  private void showDesk() {
    mWindowManager.addView(mDesktopLayout, mLayout);
    finish();
  }
  /**
   * 关闭DesktopLayout
   */
  private void closeDesk() {
    mWindowManager.removeView(mDesktopLayout);
    finish();
  }
  /**
   * 设置WindowManager
   */
  private void createWindowManager() {
    // 取得系统窗体
    mWindowManager = (WindowManager) getApplicationContext()
        .getSystemService("window");
    // 窗体的布局样式
    mLayout = new WindowManager.LayoutParams();
    // 设置窗体显示类型——TYPE_SYSTEM_ALERT(系统提示)
    mLayout.type = WindowManager.LayoutParams.TYPE_SYSTEM_ALERT;
    // 设置窗体焦点及触摸：
    // FLAG_NOT_FOCUSABLE(不能获得按键输入焦点)
    mLayout.flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE;
    // 设置显示的模式
    mLayout.format = PixelFormat.RGBA_8888;
    // 设置对齐的方法
    mLayout.gravity = Gravity.TOP | Gravity.LEFT;
    // 设置窗体宽度和高度
    mLayout.width = WindowManager.LayoutParams.WRAP_CONTENT;
    mLayout.height = WindowManager.LayoutParams.WRAP_CONTENT;
  }
}