转载请注明出处：http://blog.csdn.net/guolin_blog/article/details/8689140
大家好，今天给大家带来一个仿360手机卫士悬浮窗效果的教程，在开始之前请允许我说几句不相干的废话。
不知不觉我发现自己接触Android已有近三个年头了，期间各种的成长少不了各位高手的帮助，总是有很多高手喜欢把自己的经验写在网上，供大家来学习，我也是从中受惠了很多，在此我深表感谢。可是我发现我却从来没有将自己平时的一些心得拿出来与大家分享，共同学习，太没有奉献精神了。于是我痛定思痛，决定从今天开始写博客，希望可以指点在我后面的开发者，更快地进入Android开发者的行列当中。
好了，废话就说这么多，下面开始进入今天的主题吧。
360手机卫士我相信大家都知道，好多人手机上都会装这一款软件，那么我们对它的一个桌面悬浮窗效果想必都不会陌生。请看下图：
首先是一个小的悬浮窗显示的是当前使用了百分之多少的内存，点击一下小悬浮窗，就会弹出一个大的悬浮窗，可以一键加速。好，我们现在就来模拟实现一下类似的效果。
先谈一下基本的实现原理，这种桌面悬浮窗的效果很类似与Widget，但是它比Widget要灵活的多。主要是通过WindowManager这个类来实现的，调用这个类的addView方法用于添加一个悬浮窗，updateViewLayout方法用于更新悬浮窗的参数，removeView用于移除悬浮窗。其中悬浮窗的参数有必要详细说明一下。
WindowManager.LayoutParams这个类用于提供悬浮窗所需的参数，其中有几个经常会用到的变量：
type值用于确定悬浮窗的类型，一般设为2002，表示在所有应用程序之上，但在状态栏之下。
flags值用于确定悬浮窗的行为，比如说不可聚焦，非模态对话框等等，属性非常多，大家可以查看文档。
gravity值用于确定悬浮窗的对齐方式，一般设为左上角对齐，这样当拖动悬浮窗的时候方便计算坐标。
x值用于确定悬浮窗的位置，如果要横向移动悬浮窗，就需要改变这个值。
y值用于确定悬浮窗的位置，如果要纵向移动悬浮窗，就需要改变这个值。
width值用于指定悬浮窗的宽度。
height值用于指定悬浮窗的高度。
创建悬浮窗这种窗体需要向用户申请权限才可以的，因此还需要在AndroidManifest.xml中加入
原理介绍完了，下面我们开始用代码实现。首先在Eclipse中新建一个Android项目，项目名就叫做360FloatWindowDemo。然后写一下布局文件，布局文件非常简单，只有一个按钮，打开或新建activity_main.xml，加入如下代码：
**[html]** [view plain](http://blog.csdn.net/guolin_blog/article/details/8689140#)[copy](http://blog.csdn.net/guolin_blog/article/details/8689140#)
<div>
<embed id="ZeroClipboardMovie_1" src="http://static.blog.csdn.net/scripts/ZeroClipboard/ZeroClipboard.swf" type="application/x-shockwave-flash" width="18" height="18" align="middle" name="ZeroClipboardMovie_1">
</embed>
</div>
</div>
- <span class="tag"><</span><span class="tag-name">RelativeLayout</span> <span class="attribute">xmlns:android</span>=<span class="attribute-value">“http://schemas.android.com/apk/res/android”</span>
- <span class="attribute">xmlns:tools</span>=<span class="attribute-value">“http://schemas.android.com/tools”</span>
- <span class="attribute">android:layout_width</span>=<span class="attribute-value">“fill_parent”</span>
- <span class="attribute">android:layout_height</span>=<span class="attribute-value">“fill_parent”</span>
- <span class="attribute">tools:context</span>=<span class="attribute-value">“.MainActivity”</span> <span class="tag">></span>
- <span class="tag"><</span><span class="tag-name">Button</span>
- <span class="attribute">android:id</span>=<span class="attribute-value">“@+id/start_float_window”</span>
- <span class="attribute">android:layout_width</span>=<span class="attribute-value">“fill_parent”</span>
- <span class="attribute">android:layout_height</span>=<span class="attribute-value">“wrap_content”</span>
- <span class="attribute">android:text</span>=<span class="attribute-value">“Start Float Window”</span> <span class="tag">></span>
- <span class="tag"></</span><span class="tag-name">Button</span><span class="tag">></span>
- <span class="tag"></</span><span class="tag-name">RelativeLayout</span><span class="tag">></span>
然后再新建一个名为float_window_small.xml的布局文件，用于做为小悬浮窗的布局，在其中加入如下代码：
**[html]** [view plain](http://blog.csdn.net/guolin_blog/article/details/8689140#)[copy](http://blog.csdn.net/guolin_blog/article/details/8689140#)
<div>
<embed id="ZeroClipboardMovie_2" src="http://static.blog.csdn.net/scripts/ZeroClipboard/ZeroClipboard.swf" type="application/x-shockwave-flash" width="18" height="18" align="middle" name="ZeroClipboardMovie_2">
</embed>
</div>
</div>
- <span class="tag"><?</span><span class="tag-name">xml</span> <span class="attribute">version</span>=<span class="attribute-value">“1.0”</span> <span class="attribute">encoding</span>=<span class="attribute-value">“UTF-8”</span><span class="tag">?></span>
- <span class="tag"><</span><span class="tag-name">LinearLayout</span>
- <span class="attribute">xmlns:android</span>=<span class="attribute-value">“http://schemas.android.com/apk/res/android”</span>
- <span class="attribute">android:id</span>=<span class="attribute-value">“@+id/small_window_layout”</span>
- <span class="attribute">android:layout_width</span>=<span class="attribute-value">“60dip”</span>
- <span class="attribute">android:layout_height</span>=<span class="attribute-value">“25dip”</span>
- <span class="attribute">android:background</span>=<span class="attribute-value">“@drawable/bg_small”</span>
- <span class="tag">></span>
- <span class="tag"><</span><span class="tag-name">TextView</span>
- <span class="attribute">android:id</span>=<span class="attribute-value">“@+id/percent”</span>
- <span class="attribute">android:layout_width</span>=<span class="attribute-value">“fill_parent”</span>
- <span class="attribute">android:layout_height</span>=<span class="attribute-value">“fill_parent”</span>
- <span class="attribute">android:gravity</span>=<span class="attribute-value">“center”</span>
- <span class="attribute">android:textColor</span>=<span class="attribute-value">“#ffffff”</span>
- <span class="tag">/></span>
- <span class="tag"></</span><span class="tag-name">LinearLayout</span><span class="tag">></span>
再新建一个名为float_window_big.xml的布局文件，用于做为大悬浮窗的布局，在其中加入如下代码：
**[html]** [view plain](http://blog.csdn.net/guolin_blog/article/details/8689140#)[copy](http://blog.csdn.net/guolin_blog/article/details/8689140#)
<div>
<embed id="ZeroClipboardMovie_3" src="http://static.blog.csdn.net/scripts/ZeroClipboard/ZeroClipboard.swf" type="application/x-shockwave-flash" width="18" height="18" align="middle" name="ZeroClipboardMovie_3">
</embed>
</div>
</div>
- <span class="tag"><?</span><span class="tag-name">xml</span> <span class="attribute">version</span>=<span class="attribute-value">“1.0”</span> <span class="attribute">encoding</span>=<span class="attribute-value">“UTF-8”</span><span class="tag">?></span>
- <span class="tag"><</span><span class="tag-name">LinearLayout</span>
- <span class="attribute">xmlns:android</span>=<span class="attribute-value">“http://schemas.android.com/apk/res/android”</span>
- <span class="attribute">android:id</span>=<span class="attribute-value">“@+id/big_window_layout”</span>
- <span class="attribute">android:layout_width</span>=<span class="attribute-value">“200dip”</span>
- <span class="attribute">android:layout_height</span>=<span class="attribute-value">“100dip”</span>
- <span class="attribute">android:background</span>=<span class="attribute-value">“@drawable/bg_big”</span>
- <span class="attribute">android:orientation</span>=<span class="attribute-value">“vertical”</span>
- <span class="tag">></span>
- <span class="tag"><</span><span class="tag-name">Button</span>
- <span class="attribute">android:id</span>=<span class="attribute-value">“@+id/close”</span>
- <span class="attribute">android:layout_width</span>=<span class="attribute-value">“100dip”</span>
- <span class="attribute">android:layout_height</span>=<span class="attribute-value">“40dip”</span>
- <span class="attribute">android:layout_gravity</span>=<span class="attribute-value">“center_horizontal”</span>
- <span class="attribute">android:layout_marginTop</span>=<span class="attribute-value">“12dip”</span>
- <span class="attribute">android:text</span>=<span class="attribute-value">“关闭悬浮窗”</span>
- <span class="tag">/></span>
- <span class="tag"><</span><span class="tag-name">Button</span>
- <span class="attribute">android:id</span>=<span class="attribute-value">“@+id/back”</span>
- <span class="attribute">android:layout_width</span>=<span class="attribute-value">“100dip”</span>
- <span class="attribute">android:layout_height</span>=<span class="attribute-value">“40dip”</span>
- <span class="attribute">android:layout_gravity</span>=<span class="attribute-value">“center_horizontal”</span>
- <span class="attribute">android:text</span>=<span class="attribute-value">“返回”</span>
- <span class="tag">/></span>
- <span class="tag"></</span><span class="tag-name">LinearLayout</span><span class="tag">></span>
两个悬浮窗布局文件中用到的图片资源，大家可以随便找点图片来代替，同时我会给出源码，大家也可以从源码中取出。然后打开或创建MainActivity，这是项目的主界面，在里面加入如下代码：
**[java]** [view plain](http://blog.csdn.net/guolin_blog/article/details/8689140#)[copy](http://blog.csdn.net/guolin_blog/article/details/8689140#)
<div>
<embed id="ZeroClipboardMovie_4" src="http://static.blog.csdn.net/scripts/ZeroClipboard/ZeroClipboard.swf" type="application/x-shockwave-flash" width="18" height="18" align="middle" name="ZeroClipboardMovie_4">
</embed>
</div>
</div>
- <span class="keyword">public</span> <span class="keyword">class</span> MainActivity <span class="keyword">extends</span> Activity {
- <span class="annotation">@Override</span>
- <span class="keyword">protected</span> <span class="keyword">void</span> onCreate(Bundle savedInstanceState) {
- <span class="keyword">super</span>.onCreate(savedInstanceState);
- setContentView(R.layout.activity_main);
- Button startFloatWindow = (Button) findViewById(R.id.start_float_window);
- startFloatWindow.setOnClickListener(<span class="keyword">new</span> OnClickListener() {
- <span class="annotation">@Override</span>
- <span class="keyword">public</span> <span class="keyword">void</span> onClick(View arg0) {
- Intent intent = <span class="keyword">new</span> Intent(MainActivity.<span class="keyword">this</span>, FloatWindowService.<span class="keyword">class</span>);
- startService(intent);
- finish();
- }
- });
- }
- }
这里可以看到，MainActivity的代码非窗简单，就是对开启悬浮窗的按钮注册了一个点击事件，用于打开一个服务，然后关闭当前Activity。创建悬浮窗的逻辑都交给服务去做了。好，现在我们来创建这个服务。新建一个名为FloatWindowService的类，这个类继承自Service，在里面加入如下代码：
**[java]** [view plain](http://blog.csdn.net/guolin_blog/article/details/8689140#)[copy](http://blog.csdn.net/guolin_blog/article/details/8689140#)
<div>
<embed id="ZeroClipboardMovie_5" src="http://static.blog.csdn.net/scripts/ZeroClipboard/ZeroClipboard.swf" type="application/x-shockwave-flash" width="18" height="18" align="middle" name="ZeroClipboardMovie_5">
</embed>
</div>
</div>
- <span class="keyword">public</span> <span class="keyword">class</span> FloatWindowService <span class="keyword">extends</span> Service {
-
- <span class="comment">/**</span>
- <span class="comment"> * 用于在线程中创建或移除悬浮窗。</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> Handler handler = <span class="keyword">new</span> Handler();
-
- <span class="comment">/**</span>
- <span class="comment"> * 定时器，定时进行检测当前应该创建还是移除悬浮窗。</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> Timer timer;
-
- <span class="annotation">@Override</span>
- <span class="keyword">public</span> IBinder onBind(Intent intent) {
- <span class="keyword">return</span> <span class="keyword">null</span>;
- }
-
- <span class="annotation">@Override</span>
- <span class="keyword">public</span> <span class="keyword">int</span> onStartCommand(Intent intent, <span class="keyword">int</span> flags, <span class="keyword">int</span> startId) {
- <span class="comment">// 开启定时器，每隔0.5秒刷新一次</span>
- <span class="keyword">if</span> (timer == <span class="keyword">null</span>) {
- timer = <span class="keyword">new</span> Timer();
- timer.scheduleAtFixedRate(<span class="keyword">new</span> RefreshTask(), <span class="number"></span>, <span class="number">500</span>);
- }
- <span class="keyword">return</span> <span class="keyword">super</span>.onStartCommand(intent, flags, startId);
- }
-
- <span class="annotation">@Override</span>
- <span class="keyword">public</span> <span class="keyword">void</span> onDestroy() {
- <span class="keyword">super</span>.onDestroy();
- <span class="comment">// Service被终止的同时也停止定时器继续运行</span>
- timer.cancel();
- timer = <span class="keyword">null</span>;
- }
-
- <span class="keyword">class</span> RefreshTask <span class="keyword">extends</span> TimerTask {
-
- <span class="annotation">@Override</span>
- <span class="keyword">public</span> <span class="keyword">void</span> run() {
- <span class="comment">// 当前界面是桌面，且没有悬浮窗显示，则创建悬浮窗。</span>
- <span class="keyword">if</span> (isHome() && !MyWindowManager.isWindowShowing()) {
- handler.post(<span class="keyword">new</span> Runnable() {
- <span class="annotation">@Override</span>
- <span class="keyword">public</span> <span class="keyword">void</span> run() {
- MyWindowManager.createSmallWindow(getApplicationContext());
- }
- });
- }
- <span class="comment">// 当前界面不是桌面，且有悬浮窗显示，则移除悬浮窗。</span>
- <span class="keyword">else</span> <span class="keyword">if</span> (!isHome() && MyWindowManager.isWindowShowing()) {
- handler.post(<span class="keyword">new</span> Runnable() {
- <span class="annotation">@Override</span>
- <span class="keyword">public</span> <span class="keyword">void</span> run() {
- MyWindowManager.removeSmallWindow(getApplicationContext());
- MyWindowManager.removeBigWindow(getApplicationContext());
- }
- });
- }
- <span class="comment">// 当前界面是桌面，且有悬浮窗显示，则更新内存数据。</span>
- <span class="keyword">else</span> <span class="keyword">if</span> (isHome() && MyWindowManager.isWindowShowing()) {
- handler.post(<span class="keyword">new</span> Runnable() {
- <span class="annotation">@Override</span>
- <span class="keyword">public</span> <span class="keyword">void</span> run() {
- MyWindowManager.updateUsedPercent(getApplicationContext());
- }
- });
- }
- }
-
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 判断当前界面是否是桌面</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">boolean</span> isHome() {
- ActivityManager mActivityManager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
- List<RunningTaskInfo> rti = mActivityManager.getRunningTasks(<span class="number">1</span>);
- <span class="keyword">return</span> getHomes().contains(rti.get(<span class="number"></span>).topActivity.getPackageName());
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 获得属于桌面的应用的应用包名称</span>
- <span class="comment"> * </span>
- <span class="comment"> * @return 返回包含所有包名的字符串列表</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> List<String> getHomes() {
- List<String> names = <span class="keyword">new</span> ArrayList<String>();
- PackageManager packageManager = <span class="keyword">this</span>.getPackageManager();
- Intent intent = <span class="keyword">new</span> Intent(Intent.ACTION_MAIN);
- intent.addCategory(Intent.CATEGORY_HOME);
- List<ResolveInfo> resolveInfo = packageManager.queryIntentActivities(intent,
- PackageManager.MATCH_DEFAULT_ONLY);
- <span class="keyword">for</span> (ResolveInfo ri : resolveInfo) {
- names.add(ri.activityInfo.packageName);
- }
- <span class="keyword">return</span> names;
- }
- }
FloatWindowService的onStartCommand方法中开启了一个定时器，每隔500毫秒就会执行RefreshTask。在RefreshTask当中，要进行判断，如果手机当前是在桌面的话，就应该显示悬浮窗，如果手机打开了某一个应用程序，就应该移除悬浮窗，如果手机在桌面的话，还应该更新内存使用百分比的数据。而当FloatWindowService被销毁的时候，应该将定时器停止，否则它还会一直运行。
从上面的代码我们也可以看出，创建和移除悬浮窗，以及更新悬浮窗内的数据，都是由MyWindowManager这个类来管理的，比起直接把这些代码写在Activity或Service当中，使用一个专门的工具类来管理要好的多。不过要想创建悬浮窗，还是先要把悬浮窗的View写出来。
新建一个名叫FloatWindowSmallView的类，继承自LinearLayout。新建一个名叫FloatWindowBigView的类，也继承自LinearLayout。
在FloatWindowSmallView中加入如下代码：
**[java]** [view plain](http://blog.csdn.net/guolin_blog/article/details/8689140#)[copy](http://blog.csdn.net/guolin_blog/article/details/8689140#)
<div>
<embed id="ZeroClipboardMovie_6" src="http://static.blog.csdn.net/scripts/ZeroClipboard/ZeroClipboard.swf" type="application/x-shockwave-flash" width="18" height="18" align="middle" name="ZeroClipboardMovie_6">
</embed>
</div>
</div>
- <span class="keyword">public</span> <span class="keyword">class</span> FloatWindowSmallView <span class="keyword">extends</span> LinearLayout {
-
- <span class="comment">/**</span>
- <span class="comment"> * 记录小悬浮窗的宽度</span>
- <span class="comment"> */</span>
- <span class="keyword">public</span> <span class="keyword">static</span> <span class="keyword">int</span> viewWidth;
-
- <span class="comment">/**</span>
- <span class="comment"> * 记录小悬浮窗的高度</span>
- <span class="comment"> */</span>
- <span class="keyword">public</span> <span class="keyword">static</span> <span class="keyword">int</span> viewHeight;
-
- <span class="comment">/**</span>
- <span class="comment"> * 记录系统状态栏的高度</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">static</span> <span class="keyword">int</span> statusBarHeight;
-
- <span class="comment">/**</span>
- <span class="comment"> * 用于更新小悬浮窗的位置</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> WindowManager windowManager;
-
- <span class="comment">/**</span>
- <span class="comment"> * 小悬浮窗的参数</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> WindowManager.LayoutParams mParams;
-
- <span class="comment">/**</span>
- <span class="comment"> * 记录当前手指位置在屏幕上的横坐标值</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">float</span> xInScreen;
-
- <span class="comment">/**</span>
- <span class="comment"> * 记录当前手指位置在屏幕上的纵坐标值</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">float</span> yInScreen;
-
- <span class="comment">/**</span>
- <span class="comment"> * 记录手指按下时在屏幕上的横坐标的值</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">float</span> xDownInScreen;
-
- <span class="comment">/**</span>
- <span class="comment"> * 记录手指按下时在屏幕上的纵坐标的值</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">float</span> yDownInScreen;
-
- <span class="comment">/**</span>
- <span class="comment"> * 记录手指按下时在小悬浮窗的View上的横坐标的值</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">float</span> xInView;
-
- <span class="comment">/**</span>
- <span class="comment"> * 记录手指按下时在小悬浮窗的View上的纵坐标的值</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">float</span> yInView;
-
- <span class="keyword">public</span> FloatWindowSmallView(Context context) {
- <span class="keyword">super</span>(context);
- windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
- LayoutInflater.from(context).inflate(R.layout.float_window_small, <span class="keyword">this</span>);
- View view = findViewById(R.id.small_window_layout);
- viewWidth = view.getLayoutParams().width;
- viewHeight = view.getLayoutParams().height;
- TextView percentView = (TextView) findViewById(R.id.percent);
- percentView.setText(MyWindowManager.getUsedPercentValue(context));
- }
-
- <span class="annotation">@Override</span>
- <span class="keyword">public</span> <span class="keyword">boolean</span> onTouchEvent(MotionEvent event) {
- <span class="keyword">switch</span> (event.getAction()) {
- <span class="keyword">case</span> MotionEvent.ACTION_DOWN:
- <span class="comment">// 手指按下时记录必要数据,纵坐标的值都需要减去状态栏高度</span>
- xInView = event.getX();
- yInView = event.getY();
- xDownInScreen = event.getRawX();
- yDownInScreen = event.getRawY() – getStatusBarHeight();
- xInScreen = event.getRawX();
- yInScreen = event.getRawY() – getStatusBarHeight();
- <span class="keyword">break</span>;
- <span class="keyword">case</span> MotionEvent.ACTION_MOVE:
- xInScreen = event.getRawX();
- yInScreen = event.getRawY() – getStatusBarHeight();
- <span class="comment">// 手指移动的时候更新小悬浮窗的位置</span>
- updateViewPosition();
- <span class="keyword">break</span>;
- <span class="keyword">case</span> MotionEvent.ACTION_UP:
- <span class="comment">// 如果手指离开屏幕时，xDownInScreen和xInScreen相等，且yDownInScreen和yInScreen相等，则视为触发了单击事件。</span>
- <span class="keyword">if</span> (xDownInScreen == xInScreen && yDownInScreen == yInScreen) {
- openBigWindow();
- }
- <span class="keyword">break</span>;
- <span class="keyword">default</span>:
- <span class="keyword">break</span>;
- }
- <span class="keyword">return</span> <span class="keyword">true</span>;
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 将小悬浮窗的参数传入，用于更新小悬浮窗的位置。</span>
- <span class="comment"> * </span>
- <span class="comment"> * @param params</span>
- <span class="comment"> * 小悬浮窗的参数</span>
- <span class="comment"> */</span>
- <span class="keyword">public</span> <span class="keyword">void</span> setParams(WindowManager.LayoutParams params) {
- mParams = params;
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 更新小悬浮窗在屏幕中的位置。</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">void</span> updateViewPosition() {
- mParams.x = (<span class="keyword">int</span>) (xInScreen – xInView);
- mParams.y = (<span class="keyword">int</span>) (yInScreen – yInView);
- windowManager.updateViewLayout(<span class="keyword">this</span>, mParams);
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 打开大悬浮窗，同时关闭小悬浮窗。</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">void</span> openBigWindow() {
- MyWindowManager.createBigWindow(getContext());
- MyWindowManager.removeSmallWindow(getContext());
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 用于获取状态栏的高度。</span>
- <span class="comment"> * </span>
- <span class="comment"> * @return 返回状态栏高度的像素值。</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">int</span> getStatusBarHeight() {
- <span class="keyword">if</span> (statusBarHeight == <span class="number"></span>) {
- <span class="keyword">try</span> {
- Class<?> c = Class.forName(<span class="string">“com.android.internal.R$dimen”</span>);
- Object o = c.newInstance();
- Field field = c.getField(<span class="string">“status_bar_height”</span>);
- <span class="keyword">int</span> x = (Integer) field.get(o);
- statusBarHeight = getResources().getDimensionPixelSize(x);
- } <span class="keyword">catch</span> (Exception e) {
- e.printStackTrace();
- }
- }
- <span class="keyword">return</span> statusBarHeight;
- }
其中，对这个View的onTouchEvent事件进行了重写，用于实现拖动和点击的效果。如果发现用户触发了ACTION_DOWN事件，会记录按下时的坐标等数据。如果发现用户触发了ACTION_MOVE事件，则根据当前移动的坐标更新悬浮窗在屏幕中的位置。如果发现用户触发了ACTION_UP事件，会和ACTION_DOWN中记下的坐标对比，如果发现是相同的，则视为用户对悬浮窗进行了点击。点击小悬浮窗则打开大悬浮窗，然后我们来实现大悬浮窗的View。
在FloatWindowBigView中加入如下代码：
**[java]** [view plain](http://blog.csdn.net/guolin_blog/article/details/8689140#)[copy](http://blog.csdn.net/guolin_blog/article/details/8689140#)
<div>
<embed id="ZeroClipboardMovie_7" src="http://static.blog.csdn.net/scripts/ZeroClipboard/ZeroClipboard.swf" type="application/x-shockwave-flash" width="18" height="18" align="middle" name="ZeroClipboardMovie_7">
</embed>
</div>
</div>
- <span class="keyword">public</span> <span class="keyword">class</span> FloatWindowBigView <span class="keyword">extends</span> LinearLayout {
-
- <span class="comment">/**</span>
- <span class="comment"> * 记录大悬浮窗的宽度</span>
- <span class="comment"> */</span>
- <span class="keyword">public</span> <span class="keyword">static</span> <span class="keyword">int</span> viewWidth;
-
- <span class="comment">/**</span>
- <span class="comment"> * 记录大悬浮窗的高度</span>
- <span class="comment"> */</span>
- <span class="keyword">public</span> <span class="keyword">static</span> <span class="keyword">int</span> viewHeight;
-
- <span class="keyword">public</span> FloatWindowBigView(<span class="keyword">final</span> Context context) {
- <span class="keyword">super</span>(context);
- LayoutInflater.from(context).inflate(R.layout.float_window_big, <span class="keyword">this</span>);
- View view = findViewById(R.id.big_window_layout);
- viewWidth = view.getLayoutParams().width;
- viewHeight = view.getLayoutParams().height;
- Button close = (Button) findViewById(R.id.close);
- Button back = (Button) findViewById(R.id.back);
- close.setOnClickListener(<span class="keyword">new</span> OnClickListener() {
- <span class="annotation">@Override</span>
- <span class="keyword">public</span> <span class="keyword">void</span> onClick(View v) {
- <span class="comment">// 点击关闭悬浮窗的时候，移除所有悬浮窗，并停止Service</span>
- MyWindowManager.removeBigWindow(context);
- MyWindowManager.removeSmallWindow(context);
- Intent intent = <span class="keyword">new</span> Intent(getContext(), FloatWindowService.<span class="keyword">class</span>);
- context.stopService(intent);
- }
- });
- back.setOnClickListener(<span class="keyword">new</span> OnClickListener() {
- <span class="annotation">@Override</span>
- <span class="keyword">public</span> <span class="keyword">void</span> onClick(View v) {
- <span class="comment">// 点击返回的时候，移除大悬浮窗，创建小悬浮窗</span>
- MyWindowManager.removeBigWindow(context);
- MyWindowManager.createSmallWindow(context);
- }
- });
- }
- }
比起FloatWindowSmallView，FloatWindowBigView要简单的多，其中只有两个按钮，点击close按钮，将悬浮窗全部移除，并将Service终止。单击back按钮则移除大悬浮窗，重新创建小悬浮窗。
现在两个悬浮窗的View都已经写好了，我们来创建MyWindowManager，代码如下：
**[java]** [view plain](http://blog.csdn.net/guolin_blog/article/details/8689140#)[copy](http://blog.csdn.net/guolin_blog/article/details/8689140#)
<div>
<embed id="ZeroClipboardMovie_8" src="http://static.blog.csdn.net/scripts/ZeroClipboard/ZeroClipboard.swf" type="application/x-shockwave-flash" width="18" height="18" align="middle" name="ZeroClipboardMovie_8">
</embed>
</div>
</div>
- <span class="keyword">public</span> <span class="keyword">class</span> MyWindowManager {
-
- <span class="comment">/**</span>
- <span class="comment"> * 小悬浮窗View的实例</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">static</span> FloatWindowSmallView smallWindow;
-
- <span class="comment">/**</span>
- <span class="comment"> * 大悬浮窗View的实例</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">static</span> FloatWindowBigView bigWindow;
-
- <span class="comment">/**</span>
- <span class="comment"> * 小悬浮窗View的参数</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">static</span> LayoutParams smallWindowParams;
-
- <span class="comment">/**</span>
- <span class="comment"> * 大悬浮窗View的参数</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">static</span> LayoutParams bigWindowParams;
-
- <span class="comment">/**</span>
- <span class="comment"> * 用于控制在屏幕上添加或移除悬浮窗</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">static</span> WindowManager mWindowManager;
-
- <span class="comment">/**</span>
- <span class="comment"> * 用于获取手机可用内存</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">static</span> ActivityManager mActivityManager;
-
- <span class="comment">/**</span>
- <span class="comment"> * 创建一个小悬浮窗。初始位置为屏幕的右部中间位置。</span>
- <span class="comment"> * </span>
- <span class="comment"> * @param context</span>
- <span class="comment"> * 必须为应用程序的Context.</span>
- <span class="comment"> */</span>
- <span class="keyword">public</span> <span class="keyword">static</span> <span class="keyword">void</span> createSmallWindow(Context context) {
- WindowManager windowManager = getWindowManager(context);
- <span class="keyword">int</span> screenWidth = windowManager.getDefaultDisplay().getWidth();
- <span class="keyword">int</span> screenHeight = windowManager.getDefaultDisplay().getHeight();
- <span class="keyword">if</span> (smallWindow == <span class="keyword">null</span>) {
- smallWindow = <span class="keyword">new</span> FloatWindowSmallView(context);
- <span class="keyword">if</span> (smallWindowParams == <span class="keyword">null</span>) {
- smallWindowParams = <span class="keyword">new</span> LayoutParams();
- smallWindowParams.type = LayoutParams.TYPE_PHONE;
- smallWindowParams.format = PixelFormat.RGBA_8888;
- smallWindowParams.flags = LayoutParams.FLAG_NOT_TOUCH_MODAL
- | LayoutParams.FLAG_NOT_FOCUSABLE;
- smallWindowParams.gravity = Gravity.LEFT | Gravity.TOP;
- smallWindowParams.width = FloatWindowSmallView.viewWidth;
- smallWindowParams.height = FloatWindowSmallView.viewHeight;
- smallWindowParams.x = screenWidth;
- smallWindowParams.y = screenHeight / <span class="number">2</span>;
- }
- smallWindow.setParams(smallWindowParams);
- windowManager.addView(smallWindow, smallWindowParams);
- }
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 将小悬浮窗从屏幕上移除。</span>
- <span class="comment"> * </span>
- <span class="comment"> * @param context</span>
- <span class="comment"> * 必须为应用程序的Context.</span>
- <span class="comment"> */</span>
- <span class="keyword">public</span> <span class="keyword">static</span> <span class="keyword">void</span> removeSmallWindow(Context context) {
- <span class="keyword">if</span> (smallWindow != <span class="keyword">null</span>) {
- WindowManager windowManager = getWindowManager(context);
- windowManager.removeView(smallWindow);
- smallWindow = <span class="keyword">null</span>;
- }
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 创建一个大悬浮窗。位置为屏幕正中间。</span>
- <span class="comment"> * </span>
- <span class="comment"> * @param context</span>
- <span class="comment"> * 必须为应用程序的Context.</span>
- <span class="comment"> */</span>
- <span class="keyword">public</span> <span class="keyword">static</span> <span class="keyword">void</span> createBigWindow(Context context) {
- WindowManager windowManager = getWindowManager(context);
- <span class="keyword">int</span> screenWidth = windowManager.getDefaultDisplay().getWidth();
- <span class="keyword">int</span> screenHeight = windowManager.getDefaultDisplay().getHeight();
- <span class="keyword">if</span> (bigWindow == <span class="keyword">null</span>) {
- bigWindow = <span class="keyword">new</span> FloatWindowBigView(context);
- <span class="keyword">if</span> (bigWindowParams == <span class="keyword">null</span>) {
- bigWindowParams = <span class="keyword">new</span> LayoutParams();
- bigWindowParams.x = screenWidth / <span class="number">2</span> – FloatWindowBigView.viewWidth / <span class="number">2</span>;
- bigWindowParams.y = screenHeight / <span class="number">2</span> – FloatWindowBigView.viewHeight / <span class="number">2</span>;
- bigWindowParams.type = LayoutParams.TYPE_PHONE;
- bigWindowParams.format = PixelFormat.RGBA_8888;
- bigWindowParams.gravity = Gravity.LEFT | Gravity.TOP;
- bigWindowParams.width = FloatWindowBigView.viewWidth;
- bigWindowParams.height = FloatWindowBigView.viewHeight;
- }
- windowManager.addView(bigWindow, bigWindowParams);
- }
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 将大悬浮窗从屏幕上移除。</span>
- <span class="comment"> * </span>
- <span class="comment"> * @param context</span>
- <span class="comment"> * 必须为应用程序的Context.</span>
- <span class="comment"> */</span>
- <span class="keyword">public</span> <span class="keyword">static</span> <span class="keyword">void</span> removeBigWindow(Context context) {
- <span class="keyword">if</span> (bigWindow != <span class="keyword">null</span>) {
- WindowManager windowManager = getWindowManager(context);
- windowManager.removeView(bigWindow);
- bigWindow = <span class="keyword">null</span>;
- }
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 更新小悬浮窗的TextView上的数据，显示内存使用的百分比。</span>
- <span class="comment"> * </span>
- <span class="comment"> * @param context</span>
- <span class="comment"> * 可传入应用程序上下文。</span>
- <span class="comment"> */</span>
- <span class="keyword">public</span> <span class="keyword">static</span> <span class="keyword">void</span> updateUsedPercent(Context context) {
- <span class="keyword">if</span> (smallWindow != <span class="keyword">null</span>) {
- TextView percentView = (TextView) smallWindow.findViewById(R.id.percent);
- percentView.setText(getUsedPercentValue(context));
- }
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 是否有悬浮窗(包括小悬浮窗和大悬浮窗)显示在屏幕上。</span>
- <span class="comment"> * </span>
- <span class="comment"> * @return 有悬浮窗显示在桌面上返回true，没有的话返回false。</span>
- <span class="comment"> */</span>
- <span class="keyword">public</span> <span class="keyword">static</span> <span class="keyword">boolean</span> isWindowShowing() {
- <span class="keyword">return</span> smallWindow != <span class="keyword">null</span> || bigWindow != <span class="keyword">null</span>;
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 如果WindowManager还未创建，则创建一个新的WindowManager返回。否则返回当前已创建的WindowManager。</span>
- <span class="comment"> * </span>
- <span class="comment"> * @param context</span>
- <span class="comment"> * 必须为应用程序的Context.</span>
- <span class="comment"> * @return WindowManager的实例，用于控制在屏幕上添加或移除悬浮窗。</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">static</span> WindowManager getWindowManager(Context context) {
- <span class="keyword">if</span> (mWindowManager == <span class="keyword">null</span>) {
- mWindowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
- }
- <span class="keyword">return</span> mWindowManager;
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 如果ActivityManager还未创建，则创建一个新的ActivityManager返回。否则返回当前已创建的ActivityManager。</span>
- <span class="comment"> * </span>
- <span class="comment"> * @param context</span>
- <span class="comment"> * 可传入应用程序上下文。</span>
- <span class="comment"> * @return ActivityManager的实例，用于获取手机可用内存。</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">static</span> ActivityManager getActivityManager(Context context) {
- <span class="keyword">if</span> (mActivityManager == <span class="keyword">null</span>) {
- mActivityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
- }
- <span class="keyword">return</span> mActivityManager;
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 计算已使用内存的百分比，并返回。</span>
- <span class="comment"> * </span>
- <span class="comment"> * @param context</span>
- <span class="comment"> * 可传入应用程序上下文。</span>
- <span class="comment"> * @return 已使用内存的百分比，以字符串形式返回。</span>
- <span class="comment"> */</span>
- <span class="keyword">public</span> <span class="keyword">static</span> String getUsedPercentValue(Context context) {
- String dir = <span class="string">“/proc/meminfo”</span>;
- <span class="keyword">try</span> {
- FileReader fr = <span class="keyword">new</span> FileReader(dir);
- BufferedReader br = <span class="keyword">new</span> BufferedReader(fr, <span class="number">2048</span>);
- String memoryLine = br.readLine();
- String subMemoryLine = memoryLine.substring(memoryLine.indexOf(<span class="string">“MemTotal:”</span>));
- br.close();
- <span class="keyword">long</span> totalMemorySize = Integer.parseInt(subMemoryLine.replaceAll(<span class="string">“\\D+”</span>, <span class="string">“”</span>));
- <span class="keyword">long</span> availableSize = getAvailableMemory(context) / <span class="number">1024</span>;
- <span class="keyword">int</span> percent = (<span class="keyword">int</span>) ((totalMemorySize – availableSize) / (<span class="keyword">float</span>) totalMemorySize * <span class="number">100</span>);
- <span class="keyword">return</span> percent + <span class="string">“%”</span>;
- } <span class="keyword">catch</span> (IOException e) {
- e.printStackTrace();
- }
- <span class="keyword">return</span> <span class="string">“悬浮窗”</span>;
- }
-
- <span class="comment">/**</span>
- <span class="comment"> * 获取当前可用内存，返回数据以字节为单位。</span>
- <span class="comment"> * </span>
- <span class="comment"> * @param context</span>
- <span class="comment"> * 可传入应用程序上下文。</span>
- <span class="comment"> * @return 当前可用内存。</span>
- <span class="comment"> */</span>
- <span class="keyword">private</span> <span class="keyword">static</span> <span class="keyword">long</span> getAvailableMemory(Context context) {
- ActivityManager.MemoryInfo mi = <span class="keyword">new</span> ActivityManager.MemoryInfo();
- getActivityManager(context).getMemoryInfo(mi);
- <span class="keyword">return</span> mi.availMem;
- }
-
- }
这个类负责了控制大悬浮窗，小悬浮窗的创建和移除，系统内存使用百分比的计算等操作。
到这里基本所有的代码都已经写完了，然后我们来看一下AndroidManifest.xml文件吧，里面代码如下：
**[html]** [view plain](http://blog.csdn.net/guolin_blog/article/details/8689140#)[copy](http://blog.csdn.net/guolin_blog/article/details/8689140#)
<div>
<embed id="ZeroClipboardMovie_9" src="http://static.blog.csdn.net/scripts/ZeroClipboard/ZeroClipboard.swf" type="application/x-shockwave-flash" width="18" height="18" align="middle" name="ZeroClipboardMovie_9">
</embed>
</div>
</div>
- <span class="tag"><?</span><span class="tag-name">xml</span> <span class="attribute">version</span>=<span class="attribute-value">“1.0”</span> <span class="attribute">encoding</span>=<span class="attribute-value">“utf-8”</span><span class="tag">?></span>
- <span class="tag"><</span><span class="tag-name">manifest</span> <span class="attribute">xmlns:android</span>=<span class="attribute-value">“http://schemas.android.com/apk/res/android”</span>
- <span class="attribute">package</span>=<span class="attribute-value">“com.demo.floatwindowdemo”</span>
- <span class="attribute">android:versionCode</span>=<span class="attribute-value">“1”</span>
- <span class="attribute">android:versionName</span>=<span class="attribute-value">“1.0”</span> <span class="tag">></span>
-
- <span class="tag"><</span><span class="tag-name">uses-permission</span> <span class="attribute">android:name</span>=<span class="attribute-value">“android.permission.SYSTEM_ALERT_WINDOW”</span> <span class="tag">/></span>
-
- <span class="tag"><</span><span class="tag-name">uses-sdk</span>
- <span class="attribute">android:minSdkVersion</span>=<span class="attribute-value">“8”</span>
- <span class="attribute">android:targetSdkVersion</span>=<span class="attribute-value">“8”</span> <span class="tag">/></span>
-
- <span class="tag"><</span><span class="tag-name">application</span>
- <span class="attribute">android:allowBackup</span>=<span class="attribute-value">“true”</span>
- <span class="attribute">android:icon</span>=<span class="attribute-value">“@drawable/ic_launcher”</span>
- <span class="attribute">android:label</span>=<span class="attribute-value">“@string/app_name”</span>
- <span class="attribute">android:theme</span>=<span class="attribute-value">“@style/AppTheme”</span> <span class="tag">></span>
- <span class="tag"><</span><span class="tag-name">activity</span>
- <span class="attribute">android:name</span>=<span class="attribute-value">“com.demo.floatwindowdemo.MainActivity”</span>
- <span class="attribute">android:label</span>=<span class="attribute-value">“@string/app_name”</span> <span class="tag">></span>
- <span class="tag"><</span><span class="tag-name">intent-filter</span><span class="tag">></span>
- <span class="tag"><</span><span class="tag-name">action</span> <span class="attribute">android:name</span>=<span class="attribute-value">“android.intent.action.MAIN”</span> <span class="tag">/></span>
-
- <span class="tag"><</span><span class="tag-name">category</span> <span class="attribute">android:name</span>=<span class="attribute-value">“android.intent.category.LAUNCHER”</span> <span class="tag">/></span>
- <span class="tag"></</span><span class="tag-name">intent-filter</span><span class="tag">></span>
- <span class="tag"></</span><span class="tag-name">activity</span><span class="tag">></span>
-
- <span class="tag"><</span><span class="tag-name">service</span> <span class="attribute">android:name</span>=<span class="attribute-value">“.FloatWindowService”</span><span class="tag">></span><span class="tag"></</span><span class="tag-name">service</span><span class="tag">></span>
- <span class="tag"></</span><span class="tag-name">application</span><span class="tag">></span>
-
- <span class="tag"></</span><span class="tag-name">manifest</span><span class="tag">></span>
比较简单，记得把Activity和Service在里面注册好，还有一个权限声明需要添加的android.permission.SYSTEM_ALERT_WINDOW，表示需要用户授权允许创建系统提示窗口，也就是我们的桌面悬浮窗。
好了，现在让我们运行一下项目吧，效果如下图，主界面只有一个简单的按钮，点击按钮后，Activity被关闭，小悬浮窗显示在桌面上。其中显示着当前内存使用的百分比。
小悬浮窗是可以自由拖动的，如果打开了其它的应用程序，小悬浮窗会自动隐藏，回到桌面后小悬浮窗又会显示出来。
如果点击了小悬浮窗会弹出大悬浮窗来，这里我们大悬浮窗做的比较简单，就只有两个按钮。大悬浮窗展示的时候手机的所有其它程序是不可点的，因为焦点都在悬浮窗上了。点击返回按钮会重新展示小悬浮窗，点击关闭悬浮窗按钮，Service也会一起停掉。
360手机卫士的一键加速功能我们就不做了，就像独孤九剑一样，重要的是剑意而不是剑招，我相信大家学会了创建悬浮窗的基本原理后可以做出比360更有创意的东西。
如果大家还有什么疑问，请在下面留言。
对桌面悬浮窗感兴趣的朋友可以继续阅读 Android桌面悬浮窗进阶，QQ手机管家小火箭效果实现 。
补充：#
有朋友跟我反应，上面的代码在Android 3.0以上的系统运行会崩溃，我看了一下，确实如此，主要是3.0之后想要获取正在运行的任务，需要加上权限声明。在AndroidManifest.xml中加入
即可解决此问题。
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