Android 实现全局浮动弹窗
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