Android 实现全局浮动弹窗

Posted 2022-11-23 川峰

全局浮动小窗口，类似于微信的语音通话全局小窗口，还有一些手机的桌面的全局操作按钮等，算是比较常用，简单记录一下。

实现原理：在Application中，getSystemService(Context.WINDOW_SERVICE) 获取WindowManager，然后通过WindowManager添加View, 手势滑动时实时更新该window的LayoutParams的x | y 坐标。

核心代码：

Application中创建window:

public class App extends Application 
    private SmallWindowView mWindowView;
    private WindowManager mWindowManager;
    private WindowManager.LayoutParams mLayoutParams;
    public SmallWindowView getWindowView() 
        return mWindowView;
    
    public WindowManager getWindowManager() 
        return mWindowManager;
    
    public WindowManager.LayoutParams getLayoutParams() 
        return mLayoutParams;
    

    @Override
    public void onCreate() 
        super.onCreate();
        initSmallViewLayout();
    

    public void initSmallViewLayout() 
        mWindowView = (SmallWindowView) LayoutInflater.from(this).inflate(R.layout.small_window, null);
        mWindowManager = (WindowManager) getSystemService(Context.WINDOW_SERVICE);
        mLayoutParams = new WindowManager.LayoutParams(
                getResources().getDimensionPixelSize(R.dimen.small_window_size), // 120dp
                getResources().getDimensionPixelSize(R.dimen.small_window_size),
                WindowManager.LayoutParams.TYPE_SYSTEM_ALERT,
                WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE,
                PixelFormat.TRANSLUCENT);
        mLayoutParams.gravity = Gravity.NO_GRAVITY;
        mWindowView.setWm(mWindowManager);
        mWindowView.setWmParams(mLayoutParams);
    

    public void showWindowView() 
        if (mWindowManager != null && mWindowView.getWindowId() == null) 
            mWindowManager.addView(mWindowView, mLayoutParams);
        
    

    public void dismissWindowView() 
        if (mWindowManager != null && mWindowView != null && mWindowView.getWindowId() != null) 
            mWindowManager.removeView(mWindowView);
        
    
 

定义一个View组件，内部处理滑动改变窗口位置参数：

public class SmallWindowView extends LinearLayout 
    private final static String TAG = SmallWindowView.class.getSimpleName();
    private final int screenHeight;
    private final int screenWidth;
    private int statusHeight;
    private float mTouchStartX;
    private float mTouchStartY;

    private float mLastRawX;
    private float mLastRawY;

    private WindowManager wm;
    public WindowManager.LayoutParams wmParams;

    public WindowManager getWm() 
        return wm;
    

    public void setWm(WindowManager wm) 
        this.wm = wm;
    

    public WindowManager.LayoutParams getWmParams() 
        return wmParams;
    

    public void setWmParams(WindowManager.LayoutParams wmParams) 
        this.wmParams = wmParams;
        this.wmParams.x = 0;//screenWidth/2; // 窗口先贴附在右边
    

    public SmallWindowView(Context context) 
        this(context, null);
    

    public SmallWindowView(Context context, AttributeSet attrs) 
        this(context, attrs, 0);
    

    public SmallWindowView(final Context context, AttributeSet attrs, int defStyle) 
        super(context, attrs, defStyle);
        statusHeight = getStatusHeight(context);
        DisplayMetrics dm = getResources().getDisplayMetrics();
        screenHeight = dm.heightPixels;
        screenWidth = dm.widthPixels;
        addOnAttachStateChangeListener(new OnAttachStateChangeListener() 
            @Override
            public void onViewAttachedToWindow(View v) 
                //窗口内部按钮响应点击跳转打开新页面
                findViewById(R.id.btn).setOnClickListener(new OnClickListener() 
                    @Override
                    public void onClick(View v) 
                        Intent intent = new Intent(context, SecondActivity.class);
                        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                        context.startActivity(intent);
                    
                );
                removeOnAttachStateChangeListener(this);
            

            @Override
            public void onViewDetachedFromWindow(View v) 
            
        );
    

    /**
     * 获得状态栏的高度
     * @param context
     * @return
     */
    public static int getStatusHeight(Context context) 
        int statusHeight = -1;
        try 
            Class clazz = Class.forName("com.android.internal.R$dimen");
            Object object = clazz.newInstance();
            int height = Integer.parseInt(clazz.getField("status_bar_height")
                    .get(object).toString());
            statusHeight = context.getResources().getDimensionPixelSize(height);
         catch (Exception e) 
            e.printStackTrace();
        
        return statusHeight;
    

    @Override
    public boolean onTouchEvent(MotionEvent event) 
        switch (event.getAction()) 
            case MotionEvent.ACTION_DOWN:
                // 触摸点在View内的相对x坐标 相对Y坐标
                //mTouchStartX = event.getX();
                //mTouchStartY = event.getY();

                // 触摸点相对屏幕的x坐标 y坐标
                mLastRawX = event.getRawX();
                mLastRawY = event.getRawY() - statusHeight;
                Log.e(TAG, "startX = " + mLastRawX + " startY = " + mLastRawY);
                break;
            case MotionEvent.ACTION_MOVE:
                updateViewPosition(event.getRawX(), event.getRawY());
                mLastRawX = event.getRawX();
                mLastRawY = event.getRawY();
                break;
            case MotionEvent.ACTION_UP:
                break;
            default:
                break;
        
        return true;
    

    /** 更新浮动窗口位置参数 */
    private void updateViewPosition(float x, float y) 
        wmParams.gravity = Gravity.NO_GRAVITY;
        //计算移动距离
        int dx = (int) (x - mLastRawX);
        int dy = (int) (y - mLastRawY);
        Log.e(TAG, "updateViewPosition: dx = " + dx + " dy = " + dy);
        //默认是以屏幕中心点为（0,0）起始坐标
        wmParams.x += dx;
        wmParams.y += dy;
        Log.e(TAG, "updateViewPosition: wmParams.x = " + wmParams.x + " wmParams.y = " + wmParams.y);
        wm.updateViewLayout(this, wmParams);
    

定义一个基类Activity使用，并处理权限申请：

public class BaseActivity extends AppCompatActivity 
    private WindowManager wm;
    private SmallWindowView windowView;
    private WindowManager.LayoutParams mLayoutParams;
    private int OVERLAY_PERMISSION_REQ_CODE = 2;
    private boolean isRange = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) 
        super.onCreate(savedInstanceState);
        wm = ((App)getApplication()).getWindowManager();
        windowView = ((App)getApplication()).getWindowView();
        mLayoutParams = ((App)getApplication()).getLayoutParams();
    


    public void alertWindow() 
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M)  // 7.0 以上需要引导用去设置开启窗口浮动权限
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)  // 8.0 以上type需要设置成这个
                mLayoutParams.type = WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY;
            
            requestDrawOverLays();
         else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP)  // 6.0 动态申请
            ActivityCompat.requestPermissions(this, new String[]Manifest.permission.SYSTEM_ALERT_WINDOW, 1);
        
    

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) 
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (requestCode == 1 && grantResults[0] == PackageManager.PERMISSION_GRANTED) 
            if (wm != null && windowView.getWm() == null) 
                wm.addView(windowView, mLayoutParams);
            
         else 
            Toast.makeText(this, "权限申请失败", Toast.LENGTH_SHORT).show();
        
    


    private int[] location = new int[2]; // 小窗口位置坐标

    @Override
    public boolean onTouchEvent(MotionEvent event) 
        if (event.getAction() == MotionEvent.ACTION_DOWN) 
            isRange = calcPointRange(event);
        
        if (isRange) 
            windowView.dispatchTouchEvent(event);
        
        return super.onTouchEvent(event);
    

    /**
     *  计算当前点击事件坐标是否在小窗口内
     * @param event
     * @return
     */
    private boolean calcPointRange(MotionEvent event) 
        windowView.getLocationOnScreen(location);
        int width = windowView.getMeasuredWidth();
        int height = windowView.getMeasuredHeight();
        float curX = event.getRawX();
        float curY = event.getRawY();
        if (curX >= location[0] && curX <= location[0] + width && curY >= location[1] && curY <= location[1] + height) 
            return true;
        
        return false;
    

    private static final String TAG = "BaseActivity";

    // android 23 以上先引导用户开启这个权限 该权限动态申请不了
    @TargetApi(Build.VERSION_CODES.M)
    public void requestDrawOverLays() 
        if (!Settings.canDrawOverlays(BaseActivity.this)) 
            Toast.makeText(this, "can not DrawOverlays", Toast.LENGTH_SHORT).show();
            Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION, Uri.parse("package:" + BaseActivity.this.getPackageName()));
            startActivityForResult(intent, OVERLAY_PERMISSION_REQ_CODE);
         else 
            ((App) getApplication()).showWindowView();
            Toast.makeText(this, "权限已经授予", Toast.LENGTH_SHORT).show();
        
    

    @TargetApi(Build.VERSION_CODES.M)
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) 
        if (requestCode == OVERLAY_PERMISSION_REQ_CODE) 
            if (!Settings.canDrawOverlays(this)) 
                Toast.makeText(this, "设置权限拒绝", Toast.LENGTH_SHORT).show();
             else 
                Toast.makeText(this, "设置权限成功", Toast.LENGTH_SHORT).show();
            
        
    
    // 移除window
    public void dismissWindow() 
        ((App) getApplication()).dismissWindowView();
    
 

全局系统弹窗需要申请权限，manfiest中一定要配置SYSTEM_ALERT_WINDOW权限：

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

关键是这个权限不能通过动态权限申请的api去申请只能引导用户到设置页面手动开启，Settings.canDrawOverlays() 检测是否能在顶层绘制窗口，
new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION, Uri.parse("package:" + getPackageName())) 打开设置页面，开启悬浮窗口权限

这个必须用户手动开启，是能开启悬浮窗口的前提。

参考：https://blog.csdn.net/luweicheng24/article/details/82053070