Android使用WindowManager构造悬浮view

一般在android显示一个view都是通过activity的setcontentview设置的，但是还有一种方法，可以直接使用windowmanager在整个应用的最上层绘制我们需要显示的view，总体的效果类似于alertdialog的弹出效果。

使用windowmanager构造这样的一个悬浮view也比较简单，直接通过windowmanager.addview()方法即可。

package com.gearmotion.app.windowmanagermotion;

import android.content.context;
import android.graphics.pixelformat;
import android.graphics.rect;
import android.support.v7.app.appcompatactivity;
import android.os.bundle;
import android.view.gravity;
import android.view.layoutinflater;
import android.view.motionevent;
import android.view.view;
import android.view.viewgroup;
import android.view.windowmanager;
import android.widget.button;

public class mainactivity extends appcompatactivity implements view.onclicklistener, view.ontouchlistener {

 button mshowbtn;
 button mhidebtn;
 windowmanager mwm;
 layoutinflater mlayoutinflater;
 view mwindowview;

 @override
 protected void oncreate(bundle savedinstancestate) {
  super.oncreate(savedinstancestate);
  setcontentview(r.layout.activity_main);
  mshowbtn = (button) this.findviewbyid(r.id.showbtn);
  mhidebtn = (button) this.findviewbyid(r.id.hidebtn);
  mshowbtn.setonclicklistener(this);
  mhidebtn.setonclicklistener(this);
  init();
 }

 private void init() {
  mwm = (windowmanager) this.getapplicationcontext().getsystemservice(context.window_service);
  mlayoutinflater = layoutinflater.from(this);
 }

 @override
 public void onclick(view v) {
  if (mshowbtn.hashcode() == v.hashcode()) { //显示windowmanager
   show();
  }
  if (mhidebtn.hashcode() == v.hashcode()) { //隐藏windowmanager
   hide();
  }
 }

 private void show() {
  mwindowview = mlayoutinflater.inflate(r.layout.item_layout, null);
  view popview = mwindowview.findviewbyid(r.id.root);
  //设置popview的触摸事件，以便点击空白区域的时候使悬浮view消失
  popview.setontouchlistener(this);
  windowmanager.layoutparams lp = new windowmanager.layoutparams();
  //窗口类型同系统弹出框
  lp.type = windowmanager.layoutparams.type_system_alert;
  //响应输入法
  //lp.flags = windowmanager.layoutparams.flag_alt_focusable_im;
  //透明层
  lp.format = pixelformat.transparent;
  lp.width = windowmanager.layoutparams.match_parent;
  lp.height = windowmanager.layoutparams.match_parent;
  lp.gravity = gravity.center_vertical;
  mwm.addview(mwindowview, lp);
 }

 private void hide() {
  if (mwindowview != null && mwindowview.getparent() != null) {
   mwm.removeview(mwindowview);
  }
 }

 @override
 public boolean ontouch(view v, motionevent event) {
  int x = (int) event.getx();
  int y = (int) event.gety();
  //获取主view的可视区域
  rect globalrect = new rect();
  //获取悬浮view的可视区域
  rect tmprect = new rect();
  v.getglobalvisiblerect(globalrect);
  view child = ((viewgroup) v).getchildat(0);
  child.gethitrect(tmprect);
  if (!tmprect.contains(x, y) && globalrect.contains(x, y)) {
   hide();
  }
  return true;
 }
}

activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:tools="http://schemas.android.com/tools"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="vertical"
 tools:context=".mainactivity">

 <button
  android:id="@+id/showbtn"
  android:layout_width="match_parent"
  android:layout_height="50dp"
  android:gravity="center"
  android:text="show" />

 <button
  android:id="@+id/hidebtn"
  android:layout_width="match_parent"
  android:layout_height="50dp"
  android:gravity="center"
  android:text="hide" />
</linearlayout>

item_layout.xml:

<?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="wrap_content"
 android:gravity="center"
 android:id="@+id/root"
 android:orientation="vertical">

 <textview
  android:layout_width="match_parent"
  android:layout_height="50dp"
  android:text="i am windowmanager layout view"
  android:textsize="20sp"
  android:gravity="center"
  android:layout_gravity="center"
  android:background="#fff8dc"
  android:textcolor="#7ac5cd"/>
</linearlayout>

实现效果如下：

以上就是本文的全部内容，希望对大家学习android有所帮助，也希望大家多多支持。