Android -- 使用WindowManager实现悬浮框效果

1，原文在这里http://blog.csdn.net/qq_17250009/article/details/52908791，我只是把里面的关键步骤给注释了一下，首先来看一下我们的效果，如图（电脑太卡，截图有问题，见谅）：



2，来看一下我们的实现步骤，首先创建一个service，用于将我们的布局悬浮到我们的Android系统上去，然后通过activity来启动这个service，所以代码如下：

MainActivity.java

package com.qianmo.suspendcircle;

import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;

import static android.icu.lang.UCharacter.GraphemeClusterBreak.V;
import static android.os.Build.VERSION_CODES.M;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private Button btn_start;
private Button btn_end;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
btn_start = (Button) findViewById(R.id.btn_start);
btn_end = (Button) findViewById(R.id.btn_end);
btn_start.setOnClickListener(this);
btn_end.setOnClickListener(this);
setSupportActionBar(toolbar);

FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();

//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}

return super.onOptionsItemSelected(item);
}

@Override
public void onClick(View v) {
switch (v.getId()) {
//启动服务
case R.id.btn_start:
Intent intent = new Intent(MainActivity.this, WindowService.class);
startService(intent);
break;
//停止服务
case R.id.btn_end:
Intent intent1 = new Intent(MainActivity.this, WindowService.class);
stopService(intent1);
break;
}
}
}

MainActivity这个没什么好说的，就是启动service和关闭service而已，主要是那个Service，代码如下：

WindowService.java

package com.qianmo.suspendcircle;

import android.app.ActivityManager;
import android.app.Service;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.graphics.PixelFormat;
import android.os.IBinder;
import android.support.annotation.Nullable;
import android.util.Log;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.WindowManager;
import android.widget.TextView;

import java.util.List;

/**
* Created by Administrator on 2017/2/9 0009.
* E-Mail：543441727@qq.com
*/

public class WindowService extends Service {
private final String TAG = this.getClass().getSimpleName();

private WindowManager.LayoutParams wmParams;
private WindowManager mWindowManager;
private View mWindowView;
private TextView mPercenrTv;

private int mStartX;
private int mStartY;
private int mEndX;
private int mEndY;

@Override
public void onCreate() {
super.onCreate();
Log.i(TAG, "Create");
initWindowParams();
initView();
addWindowViewZWindow();
initClick();
}

/**
* 点击事件和拖拽事件
*/
private void initClick() {
mPercenrTv.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
switch (event.getAction()) {
//按下鼠标的时候记录下屏幕的位置
case MotionEvent.ACTION_DOWN:
mStartX = (int) event.getRawX();
mStartY = (int) event.getRawY();

break;
case MotionEvent.ACTION_MOVE:
mEndX = (int) event.getRawX();
mEndY = (int) event.getRawY();
if (needIntercept()) {
//getRawX是触摸位置相对于整个屏幕的位置，getX是控触摸点相对于控件最左边的位置
wmParams.x = (int) event.getRawX() - mWindowView.getMeasuredWidth() / 2;
wmParams.y = (int) event.getRawY() - mWindowView.getMeasuredHeight() / 2;
mWindowManager.updateViewLayout(mWindowView, wmParams);
return true;
}
break;
case MotionEvent.ACTION_UP:
if (needIntercept()) {
return true;
}
break;
}

return false;
}
});

mPercenrTv.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Log.i(TAG, "点击了");
if (isAppAtBackground(WindowService.this)) {
Intent intent = new Intent(WindowService.this, MainActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}
}
});

}

/**
* 判断当前应用是前台还是后台
*/
private boolean isAppAtBackground(final Context context) {
ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
List<ActivityManager.RunningTaskInfo> tasks = am.getRunningTasks(1);
if (!tasks.isEmpty()) {
ComponentName topActivity = tasks.get(0).topActivity;
if (!topActivity.getPackageName().equals(context.getPackageName())) {
return true;
}
}
return false;
}

/**
* 判断是否拦截，根据滑动的距离
*
* @return
*/
private boolean needIntercept() {
if (Math.abs(mStartX - mEndX) > 30 || Math.abs(mStartY - mEndY) > 30) {
return true;
}
return false;
}

/**
* 添加View到桌面Window界面上
*/
private void addWindowViewZWindow() {
mWindowManager.addView(mWindowView, wmParams);
}

/**
* 初始化加速球控件
*/
private void initView() {
mWindowView = LayoutInflater.from(getApplication()).inflate(R.layout.layout_window, null);
mPercenrTv = (TextView) mWindowView.findViewById(R.id.percentTv);
}

/**
* 初始化Window对象的参数
*/
private void initWindowParams() {
//1,获取系统级别的WindowManager
mWindowManager = (WindowManager) getApplication().getSystemService(getApplication().WINDOW_SERVICE);
wmParams = new WindowManager.LayoutParams();

//2,添加系统参数，确保悬浮框能显示到手机上

//电话窗口。它用于电话交互（特别是呼入）。它置于所有应用程序之上，状态栏之下。
wmParams.type = WindowManager.LayoutParams.TYPE_PHONE;
//期望的位图格式。默认为不透明
wmParams.format = PixelFormat.TRANSLUCENT;
//不许获得焦点
wmParams.flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE;
//窗口停靠位置
wmParams.gravity = Gravity.LEFT | Gravity.TOP;
wmParams.width = WindowManager.LayoutParams.WRAP_CONTENT;
wmParams.height = WindowManager.LayoutParams.WRAP_CONTENT;

}

@Override
public void onDestroy() {
super.onDestroy();
if (mWindowView != null) {
//移除悬浮窗口
Log.i(TAG, "removeView");
mWindowManager.removeView(mWindowView);
}
Log.i(TAG, "onDestroy");
}

@Nullable
@Override
public IBinder onBind(Intent intent) {
return null;
}
}

　由于注释很详细了，就不给大家说代码了

　最后附上源码地址：　https://github.com/543441727/SuspendWindow.git