背景

     dialog 对话框只提供Activity上下文显示环境，但是很多时候需要在后台服务中显示对话框的场景，例如后台收到哪个反馈时，弹出对应的对话框提示用户。

解决方案：

1、添加权限：

<!--services权限-->
<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
<uses-permission android:name="android.permission.SYSTEM_OVERLAY_WINDOW" />

2、添加getApplicationContext()

记得做判断8.0以上系统
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {Objects.requireNonNull(window).setType((WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY));
} else {Objects.requireNonNull(window).setType((WindowManager.LayoutParams.TYPE_SYSTEM_ALERT));
}

    private VoiceDialog boxDialog;private void showDialog() {View inflate = LayoutInflater.from(getApplicationContext()).inflate(R.layout.donghua_layout, null, false);boxDialog = new VoiceDialog(getApplicationContext(), inflate, VoiceDialog.LocationView.BOTTOM);
//        boxDialog.setCancelable(false);//是否可以点击DialogView外关闭Dialog
//        boxDialog.setCanceledOnTouchOutside(false);//是否可以按返回按钮关闭DialogboxDialog.show();boxDialog.showVoiceLum();}

3、对话框代码

/*** 语音* 对话框*/public class VoiceDialog extends Dialog {//Dialog Viewprivate View view;//Dialog弹出位置private LocationView locationView = LocationView.BOTTOM;/*** @param context 上下文* @param view    Dialog View*/public VoiceDialog(Context context, View view) {super(context, R.style.BoxDialog);this.view = view;}/*** @param context      上下文* @param view         Dialog View* @param locationView Dialog*                     弹出位置*/public VoiceDialog(Context context, View view, LocationView locationView) {super(context, R.style.BoxDialog);this.view = view;this.locationView = locationView;waveLineView = view.findViewById(R.id.waveLineView);tvContView = view.findViewById(R.id.tv_content);closeDialog = view.findViewById(R.id.close_dialog);showTxtContent("请说话");clickListener();}@SuppressLint("RtlHardcoded")@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);if (null != view) {setContentView(view);setCancelable(true);//点击外部是否可以关闭DialogsetCanceledOnTouchOutside(true);//返回键是否可以关闭DialogWindow window = this.getWindow();assert window != null;switch (locationView) {case TOP:window.setGravity(Gravity.TOP);break;case BOTTOM:window.setGravity(Gravity.BOTTOM);break;case CENTER:window.setGravity(Gravity.CENTER);break;}if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {Objects.requireNonNull(window).setType((WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY));} else {Objects.requireNonNull(window).setType((WindowManager.LayoutParams.TYPE_SYSTEM_ALERT));}window.setBackgroundDrawableResource(android.R.color.transparent);WindowManager.LayoutParams params = window.getAttributes();params.width = WindowManager.LayoutParams.WRAP_CONTENT;params.height = WindowManager.LayoutParams.WRAP_CONTENT;params.y = 10;//设置与底部距离window.setAttributes(params);}}/*** 语音* 播放动画*/private WaveLineView waveLineView;private TextView tvContView;private ImageView closeDialog;public void showVoiceLum() {if (waveLineView != null) {waveLineView.startAnim();waveLineView.onResume();}}/*** 语音* 停止动画*/public void stopAminVoice() {if (waveLineView != null) {waveLineView.onPause();waveLineView.clearDraw();}}/*** 设置* 内容*/public void showTxtContent(String ct) {if (tvContView != null) {tvContView.setText(ct);}}/*** 显示* 位置*/public enum LocationView {CENTER, TOP, BOTTOM}/*** 事件* 监听*/private void clickListener() {if (closeDialog != null) {closeDialog.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View view) {dismiss();}});}}}

4、对话框布局代码

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:app="http://schemas.android.com/apk/res-auto"xmlns:tools="http://schemas.android.com/tools"android:layout_width="wrap_content"android:layout_height="wrap_content"><RelativeLayoutandroid:id="@+id/parent_layout"android:layout_width="@dimen/dp_160"android:layout_height="@dimen/dp_38"android:background="@drawable/kdvoice_shape"><ImageViewandroid:id="@+id/close_dialog"android:layout_width="@dimen/dp_10"android:layout_height="@dimen/dp_10"android:layout_alignRight="@id/tv_content"android:layout_alignParentRight="true"android:layout_marginTop="@dimen/dp_4"android:layout_marginRight="@dimen/dp_8"android:src="@drawable/closed_icon" /><TextViewandroid:id="@+id/tv_content"android:layout_width="@dimen/dp_140"android:layout_height="@dimen/dp_20"android:layout_marginLeft="@dimen/dp_5"android:ellipsize="end"android:gravity="center_horizontal"android:maxEms="26"android:paddingTop="@dimen/dp_3"android:singleLine="true"android:text="请说话"android:textColor="@color/color666"android:textSize="@dimen/sp_10" /><jaygoo.widget.wlv.WaveLineViewandroid:id="@+id/waveLineView"android:layout_width="@dimen/dp_160"android:layout_height="@dimen/dp_18"android:layout_below="@id/tv_content"android:layout_alignParentBottom="true"android:layout_centerHorizontal="true"android:layout_marginBottom="@dimen/dp_4"app:wlvBackgroundColor="@color/white"app:wlvFineLineWidth="@dimen/dp_0.2"app:wlvLineColor="@color/app_color_theme_5"app:wlvMoveSpeed="290"app:wlvThickLineWidth="@dimen/dp_0.5" /></RelativeLayout></RelativeLayout>

5、对话框样式

  <style name="BoxDialog" parent="@android:style/Theme.Holo.Dialog"> <!-- 是否有边框 --><item name="android:windowFrame">@null</item> <!--是否在悬浮Activity之上 --><item name="android:windowIsFloating">true</item> <!-- 标题 --><item name="android:windowNoTitle">true</item> <!--阴影 --><item name="android:windowIsTranslucent">true</item> <!--背景透明--><item name="android:windowBackground">@android:color/transparent</item> <!--可加入动画--></style>

完毕！！！

注意由于业务场景需要用到的语音播放效果库WaveLineView

 implementation 'com.github.Jay-Goo:WaveLineView:v1.0.4'