仿iphone快速导航悬浮球

用过iphone的朋友都知道，iPhone有个圆球辅助工具，它漂浮在你的手机屏幕(在任何APP之上)，你可以将它移动到任何地方，它叫做AssistiveTouch，本篇模拟该软件实现一个小案例，主要是实现它的界面，首先来看看实现的效果吧：

拖动小圆球：

点击弹出pop窗口：

为了让辅助工具一直悬浮在窗口之上，这里使用的机制是通过在程序初始化是，启动一个service，在service的onCreate() 函数中使用LayoutInflater来加载一个view，而这个view就是辅助球的布局文件：floatball.xml，然后对它进行onclick事件的监听，setOnClickListener监听到辅助球点击事件之后，就创建一个PopupWindow，弹出如上的菜单界面，大体的实现就是这样。

其实，实现窗口悬浮于最前面的一个重要属性是：WindowManager.LayoutParams.TYPE_PHONE

我们只要将WindowManager.LayoutParams的type属性设置为 WindowManager.LayoutParams.TYPE_PHONE就可以实现悬浮最前面。

工程目录结构：

部分代码解析：

MyApplication.java：

package com.tyd.floatball.util;
import android.app.Application;
import android.view.WindowManager;
public class MyApplication extends Application {
    private WindowManager.LayoutParams wmParams = new WindowManager.LayoutParams();
    public WindowManager.LayoutParams getMywmParams() {
        return wmParams;
    }
}  

MainActivity.java：

package com.tyd.floatball.ui;  

import com.tyd.floatball.R;
import com.tyd.floatball.R.layout;
import com.tyd.floatball.service.TopFloatService;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;  

public class MainActivity extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        Intent service = new Intent();
        service.setClass(this, TopFloatService.class);
        //启动服务
        startService(service);
    }
}  

TopFloatService.java：

package com.tyd.floatball.service;  

import android.app.Service;
import android.content.Intent;
import android.graphics.PixelFormat;
import android.graphics.Rect;
import android.graphics.drawable.BitmapDrawable;
import android.os.IBinder;
import android.util.DisplayMetrics;
import android.view.Gravity;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnKeyListener;
import android.view.View.OnTouchListener;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.PopupWindow;
import android.widget.RelativeLayout;
import android.widget.Toast;
import com.tyd.floatball.R;
import com.tyd.floatball.util.MyApplication;  

public class TopFloatService extends Service implements OnClickListener,OnKeyListener{
    WindowManager wm = null;
    WindowManager.LayoutParams ballWmParams = null;
    private View ballView;
    private View menuView;
    private float mTouchStartX;
    private float mTouchStartY;
    private float x;
    private float y;
    private RelativeLayout menuLayout;
    private Button floatImage;
    private PopupWindow pop;
    private RelativeLayout menuTop;
    private boolean ismoving = false;  

    @Override
    public void onCreate() {
        super.onCreate();
        //加载辅助球布局
        ballView = LayoutInflater.from(this).inflate(R.layout.floatball, null);
        floatImage = (Button)ballView.findViewById(R.id.float_image);
        setUpFloatMenuView();
        createView();
    }  

    /**
     * 窗口菜单初始化
     */
    private void setUpFloatMenuView(){
        menuView = LayoutInflater.from(this).inflate(R.layout.floatmenu, null);
        menuLayout = (RelativeLayout)menuView.findViewById(R.id.menu);
        menuTop = (RelativeLayout)menuView.findViewById(R.id.lay_main);
        menuLayout.setOnClickListener(this);
        menuLayout.setOnKeyListener(this);
        menuTop.setOnClickListener(this);
    }  

    /**
     * 通过MyApplication创建view，并初始化显示参数
     */
    private void createView() {
        wm = (WindowManager) getApplicationContext().getSystemService("window");
        ballWmParams =  ((MyApplication) getApplication()).getMywmParams();
        ballWmParams.type = WindowManager.LayoutParams.TYPE_PHONE;
        ballWmParams.flags |= WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE;
        ballWmParams.gravity = Gravity.LEFT | Gravity.TOP;
        ballWmParams.x = 0;
        ballWmParams.y = 0;
        ballWmParams.width = WindowManager.LayoutParams.WRAP_CONTENT;
        ballWmParams.height = WindowManager.LayoutParams.WRAP_CONTENT;
        ballWmParams.format = PixelFormat.RGBA_8888;
        //添加显示层
        wm.addView(ballView, ballWmParams);
        //注册触碰事件监听器
        floatImage.setOnTouchListener(new OnTouchListener() {
            public boolean onTouch(View v, MotionEvent event) {
                x = event.getRawX();
                y = event.getRawY();
                switch (event.getAction()) {
                case MotionEvent.ACTION_DOWN:
                    ismoving = false;
                    mTouchStartX = (int)event.getX();
                    mTouchStartY = (int)event.getY();
                    break;
                case MotionEvent.ACTION_MOVE:
                    ismoving = true;
                    updateViewPosition();
                    break;
                case MotionEvent.ACTION_UP:
                    mTouchStartX = mTouchStartY = 0;
                    break;
                }
                //如果拖动则返回false，否则返回true
                if(ismoving == false){
                    return false;
                }else{
                    return true;
                }
            }  

        });
        //注册点击事件监听器
        floatImage.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                DisplayMetrics dm = getResources().getDisplayMetrics();
                pop = new PopupWindow(menuView, dm.widthPixels, dm.heightPixels);
                pop.showAtLocation(ballView, Gravity.CENTER, 0, 0);
                pop.update();
            }
        });
    }  

    /**
     * 更新view的显示位置
     */
    private void updateViewPosition() {
        ballWmParams.x = (int) (x - mTouchStartX);
        ballWmParams.y = (int) (y - mTouchStartY);
        wm.updateViewLayout(ballView, ballWmParams);
    }  

    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }  

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.lay_main:
            Toast.makeText(getApplicationContext(), "111", 1000).show();
            break;  

        default:
            if(pop!=null && pop.isShowing()){
                pop.dismiss();
            }
            break;
        }  

    }  

    @Override
    public boolean onKey(View v, int keyCode, KeyEvent event) {
        Toast.makeText(getApplicationContext(), "keyCode:"+keyCode, 1000).show();
        switch (keyCode) {
        case KeyEvent.KEYCODE_HOME:
            pop.dismiss();
            break;
        default:
            break;
        }
        return true;
    }  

} 

辅助球的布局文件 floatball.xml：

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:layout_gravity="center_vertical">  

    <Button
        android:id="@+id/float_image"
        android:layout_width="50dp"
        android:layout_height="50dp"
        android:background="@drawable/selector_btn_assistive"
        />  

</FrameLayout>  

窗口菜单的布局文件floatmenu.xml：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/menu"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@drawable/transparent" >  

    <LinearLayout
        android:layout_width="@dimen/size_dialog"
        android:layout_height="@dimen/size_dialog"
        android:layout_centerInParent="true"
        android:background="@drawable/shape_background_assistivetouch"
        android:orientation="vertical" >  

        <RelativeLayout
            android:id="@+id/lay_main"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:orientation="vertical"
            android:padding="4.0px"
            android:visibility="visible" >  

            <TextView
                android:id="@+id/btn_apps"
                style="@style/Icon"
                android:layout_centerInParent="true"
                android:drawableTop="@drawable/selector_ic_apps"
                android:text="@string/apps" />  

            <TextView
                android:id="@+id/btn_home_screen"
                style="@style/Icon"
                android:layout_alignParentBottom="true"
                android:layout_centerHorizontal="true"
                android:drawableTop="@drawable/selector_ic_home"
                android:text="@string/home_screen" />  

            <TextView
                android:id="@+id/btn_setting"
                style="@style/Icon"
                android:layout_alignParentRight="true"
                android:layout_centerVertical="true"
                android:drawableTop="@drawable/selector_ic_phone"
                android:text="@string/setting" />  

            <TextView
                android:id="@+id/btn_lock_screen"
                style="@style/Icon"
                android:layout_centerHorizontal="true"
                android:drawableTop="@drawable/selector_ic_power_down"
                android:text="@string/lock_screen" />  

            <TextView
                android:id="@+id/btn_favor"
                style="@style/Icon"
                android:layout_alignParentLeft="true"
                android:layout_centerVertical="true"
                android:drawableTop="@drawable/selector_ic_star"
                android:text="@string/favor" />
        </RelativeLayout>
    </LinearLayout>  

</RelativeLayout> 

AndroidManifest.xml：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.tyd.floatball"
    android:versionCode="1"
    android:versionName="1.0" >
    <uses-sdk android:minSdkVersion="14" />  

    <application
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:name=".util.MyApplication">
        <activity
            android:label="@string/app_name"
            android:name=".ui.MainActivity" >
            <intent-filter >
                <action android:name="android.intent.action.MAIN" />  

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <service
                android:name=".service.TopFloatService"
                android:enabled="true"
                android:exported="true"
            />
    </application>  

    <uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
    <uses-permission android:name="android.permission.DISABLE_KEYGUARD"/>
</manifest>

该实例我已经将源码整理打包，进行了上传，下面是资源的下载地址：

http://download.csdn.net/detail/wulianghuan/5364129