使用WindowManager实现Android悬浮窗

WindowManager介绍

  通过Context.getSystemService(Context.WINDOW_SERVICE)可以获得 WindowManager对象。

  每一个WindowManager对象都和一个特定的 Display绑定。

  想要获取一个不同的display的WindowManager,可以用 createDisplayContext(Display)来获取那个display的 Context,之后再使用:

Context.getSystemService(Context.WINDOW_SERVICE)来获取WindowManager。

  使用WindowManager可以在其他应用最上层,甚至手机桌面最上层显示窗口。

  调用的是WindowManager继承自基类的addView方法和removeView方法来显示和隐藏窗口。具体见后面的实例。

  另:API 17推出了Presentation,它将自动获取display的Context和WindowManager,可以方便地在另一个display上显示窗口。

WindowManager实现悬浮窗例子

声明权限

  首先在manifest中添加如下权限:

<!-- 显示顶层浮窗 -->
<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />

 注意:在MIUI上需要在设置中打开本应用的”显示悬浮窗”开关,并且重启应用,否则悬浮窗只能显示在本应用界面内,不能显示在手机桌面上。

服务获取和基本参数设置

// 获取应用的Context
mContext = context.getApplicationContext();
// 获取WindowManager
mWindowManager = (WindowManager) mContext
        .getSystemService(Context.WINDOW_SERVICE);

参数设置:

final WindowManager.LayoutParams params = new WindowManager.LayoutParams();
        // 类型
        params.type = WindowManager.LayoutParams.TYPE_SYSTEM_ALERT;
        // WindowManager.LayoutParams.TYPE_SYSTEM_ALERT
        // 设置flag
        int flags = WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM;
        // | 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.MATCH_PARENT;
        params.height = LayoutParams.MATCH_PARENT;
        params.gravity = Gravity.CENTER;

点击和按键事件

  除了View中的各个控件的点击事件之外,弹窗View的消失控制需要一些处理。

  点击弹窗外部可隐藏弹窗的效果,首先,悬浮窗是全屏的,只不过最外层的是透明或者半透明的:

  布局如下:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_gravity="center"
    android:background="@color/darken_background"
    android:gravity="center"
    android:orientation="vertical" >
    <RelativeLayout
        android:id="@+id/popup_window"
        android:layout_width="@dimen/dialog_window_width"
        android:layout_height="@dimen/dialog_window_height"
        android:background="@color/white"
        android:orientation="vertical" >
        <TextView
            android:id="@+id/title"
            android:layout_width="match_parent"
            android:layout_height="@dimen/dialog_title_height"
            android:gravity="center"
            android:text="@string/default_title"
            android:textColor="@color/dialog_title_text_color"
            android:textSize="@dimen/dialog_title_text_size" />
        <View
            android:id="@+id/title_divider"
            android:layout_width="match_parent"
            android:layout_height="2dp"
            android:layout_below="@id/title"
            android:background="@drawable/dialog_title_divider" />
        <TextView
            android:id="@+id/content"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@id/title_divider"
            android:gravity="center"
            android:padding="@dimen/dialog_content_padding_side"
            android:text="@string/default_content"
            android:textColor="@color/dialog_content_text_color"
            android:textSize="@dimen/dialog_content_text_size" />
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:orientation="horizontal"
            android:paddingBottom="@dimen/dialog_content_padding_bottom"
            android:paddingLeft="@dimen/dialog_content_padding_side"
            android:paddingRight="@dimen/dialog_content_padding_side" >
            <Button
                android:id="@+id/negativeBtn"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@drawable/promote_window_negative_btn_selector"
                android:focusable="true"
                android:padding="@dimen/dialog_button_padding"
                android:text="@string/default_btn_cancel"
                android:textColor="@color/dialog_negative_btn_text_color"
                android:textSize="@dimen/dialog_button_text_size" />
            <Button
                android:id="@+id/positiveBtn"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="18dp"
                android:layout_weight="1"
                android:background="@drawable/promote_window_positive_btn_selector"
                android:focusable="true"
                android:padding="@dimen/dialog_button_padding"
                android:text="@string/default_btn_ok"
                android:textColor="@color/dialog_positive_btn_text_color"
                android:textSize="@dimen/dialog_button_text_size" />
        </LinearLayout>
    </RelativeLayout>
</LinearLayout>
popupwindow.xml

点击外部可消除设置:

// 点击窗口外部区域可消除
        // 这点的实现主要将悬浮窗设置为全屏大小,外层有个透明背景,中间一部分视为内容区域
        // 所以点击内容区域外部视为点击悬浮窗外部
        final View popupWindowView = view.findViewById(R.id.popup_window);// 非透明的内容区域
        view.setOnTouchListener(new OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                LogUtil.i(LOG_TAG, "onTouch");
                int x = (int) event.getX();
                int y = (int) event.getY();
                Rect rect = new Rect();
                popupWindowView.getGlobalVisibleRect(rect);
                if (!rect.contains(x, y)) {
                    WindowUtils.hidePopupWindow();
                }
                LogUtil.i(LOG_TAG, "onTouch : " + x + ", " + y + ", rect: "
                        + rect);
                return false;
            }
        });

点击Back键可隐藏弹窗:

  注意Flag不能设置WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE。

// 点击back键可消除
        view.setOnKeyListener(new OnKeyListener() {
            @Override
            public boolean onKey(View v, int keyCode, KeyEvent event) {
                switch (keyCode) {
                case KeyEvent.KEYCODE_BACK:
                    WindowUtils.hidePopupWindow();
                    return true;
                default:
                    return false;
                }
            }
        });

完整效果

  完整代码:

MainActivity

package com.example.hellowindow;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity {
    private Handler mHandler = null;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mHandler = new Handler();
        Button button = (Button) findViewById(R.id.button);
        button.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                mHandler.postDelayed(new Runnable() {
                    @Override
                    public void run() {
                        WindowUtils.showPopupWindow(MainActivity.this);
                    }
                }, 1000 * 3);
            }
        });
    }
}

WindowUtils

package com.example.hellowindow;
import android.content.Context;
import android.graphics.PixelFormat;
import android.graphics.Rect;
import android.view.Gravity;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnKeyListener;
import android.view.View.OnTouchListener;
import android.view.WindowManager;
import android.view.View.OnClickListener;
import android.view.WindowManager.LayoutParams;
import android.widget.Button;
/**
 * 弹窗辅助类
 *
 * @ClassName WindowUtils
 *
 *
 */
public class WindowUtils {
    private static final String LOG_TAG = "WindowUtils";
    private static View mView = null;
    private static WindowManager mWindowManager = null;
    private static Context mContext = null;
    public static Boolean isShown = false;
    /**
     * 显示弹出框
     *
     * @param context
     * @param view
     */
    public static void showPopupWindow(final Context context) {
        if (isShown) {
            LogUtil.i(LOG_TAG, "return cause already shown");
            return;
        }
        isShown = true;
        LogUtil.i(LOG_TAG, "showPopupWindow");
        // 获取应用的Context
        mContext = context.getApplicationContext();
        // 获取WindowManager
        mWindowManager = (WindowManager) mContext
                .getSystemService(Context.WINDOW_SERVICE);
        mView = setUpView(context);
        final WindowManager.LayoutParams params = new WindowManager.LayoutParams();
        // 类型
        params.type = WindowManager.LayoutParams.TYPE_SYSTEM_ALERT;
        // WindowManager.LayoutParams.TYPE_SYSTEM_ALERT
        // 设置flag
        int flags = WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM;
        // | 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.MATCH_PARENT;
        params.height = LayoutParams.MATCH_PARENT;
        params.gravity = Gravity.CENTER;
        mWindowManager.addView(mView, params);
        LogUtil.i(LOG_TAG, "add view");
    }
    /**
     * 隐藏弹出框
     */
    public static void hidePopupWindow() {
        LogUtil.i(LOG_TAG, "hide " + isShown + ", " + mView);
        if (isShown && null != mView) {
            LogUtil.i(LOG_TAG, "hidePopupWindow");
            mWindowManager.removeView(mView);
            isShown = false;
        }
    }
    private static View setUpView(final Context context) {
        LogUtil.i(LOG_TAG, "setUp view");
        View view = LayoutInflater.from(context).inflate(R.layout.popupwindow,
                null);
        Button positiveBtn = (Button) view.findViewById(R.id.positiveBtn);
        positiveBtn.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                LogUtil.i(LOG_TAG, "ok on click");
                // 打开安装包
                // 隐藏弹窗
                WindowUtils.hidePopupWindow();
            }
        });
        Button negativeBtn = (Button) view.findViewById(R.id.negativeBtn);
        negativeBtn.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                LogUtil.i(LOG_TAG, "cancel on click");
                WindowUtils.hidePopupWindow();
            }
        });
        // 点击窗口外部区域可消除
        // 这点的实现主要将悬浮窗设置为全屏大小,外层有个透明背景,中间一部分视为内容区域
        // 所以点击内容区域外部视为点击悬浮窗外部
        final View popupWindowView = view.findViewById(R.id.popup_window);// 非透明的内容区域
        view.setOnTouchListener(new OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                LogUtil.i(LOG_TAG, "onTouch");
                int x = (int) event.getX();
                int y = (int) event.getY();
                Rect rect = new Rect();
                popupWindowView.getGlobalVisibleRect(rect);
                if (!rect.contains(x, y)) {
                    WindowUtils.hidePopupWindow();
                }
                LogUtil.i(LOG_TAG, "onTouch : " + x + ", " + y + ", rect: "
                        + rect);
                return false;
            }
        });
        // 点击back键可消除
        view.setOnKeyListener(new OnKeyListener() {
            @Override
            public boolean onKey(View v, int keyCode, KeyEvent event) {
                switch (keyCode) {
                case KeyEvent.KEYCODE_BACK:
                    WindowUtils.hidePopupWindow();
                    return true;
                default:
                    return false;
                }
            }
        });
        return view;
    }
}

参考资料

  WindowManager:

http://developer.android.com/reference/android/view/WindowManager.html

  参考实例:

http://blog.csdn.net/deng0zhaotai/article/details/16827719

http://www.xsmile.net/?p=538

http://blog.csdn.net/guolin_blog/article/details/8689140

  简单说明:

  Android之Window、WindowManager与窗口管理:

http://blog.csdn.net/xieqibao/article/details/6567814

  Android系统服务-WindowManager:

http://blog.csdn.net/chenyafei617/article/details/6577940

进一步的学习:

  老罗的Android之旅:

  Android Activity的窗口对象Window的创建过程分析:

http://blog.csdn.net/luoshengyang/article/details/8223770

  窗口管理服务WindowManagerService的简要介绍和学习计划:

http://blog.csdn.net/luoshengyang/article/details/8462738

  Android核心分析之窗口管理:

http://blog.csdn.net/maxleng/article/details/5557758