1.配置：

1.1 AndroidManifest.xml中添加权限和FileProvider：

1. ——————————————————————————————————————–
2. <uses-permission android:name=“android.permission.INTERNET”/>
3. <uses-permission android:name=“android.permission.READ_EXTERNAL_STORAGE”/>
4. <uses-permission android:name=“android.permission.WRITE_EXTERNAL_STORAGE”/>
5. <uses-permission android:name=“android.permission.REQUEST_INSTALL_PACKAGES” />
6. ——————————————————————————————————————–
8. <provider
9. android:name=“androidx.core.content.FileProvider”
10. android:authorities=“com.fengzhi.wuyemanagement.fileprovider”
11. android:grantUriPermissions=“true”
12. android:exported=“false”>
13. <meta-data
14. android:name=“android.support.FILE_PROVIDER_PATHS”
15. android:resource=“@xml/file_paths” />
16. </provider>

1.2 新建文件（路径：res\xml\file_paths.xml）:

1. <paths>
2. <external-path path=“.” name=“external_storage_root” />
3. </paths>

1.3 (app的)build.gradle:

1. implementation “com.lzy.net:okgo:3.0.4”//okgo 网络请求
2. implementation ‘com.google.code.gson:gson:2.8.2’//gson
3. implementation “org.permissionsdispatcher:permissionsdispatcher:4.3.1”//权限
4. annotationProcessor “org.permissionsdispatcher:permissionsdispatcher-processor:4.3.1”//权限

2.这里以点击按钮进行更新为例：

2.1 核心代码：

1. private int version;
2. /* 更新进度条 */
3. private ProgressBar mProgress;
4. private AlertDialog mDownloadDialog;
6. ——————————————————————————————————————–
8. //点击按钮，检查权限，，，检查更新的方法
9. @NeedsPermission({Manifest.permission.READ_EXTERNAL_STORAGE,
10. Manifest.permission.WRITE_EXTERNAL_STORAGE,
11. Manifest.permission.REQUEST_INSTALL_PACKAGES})
12. protected void checkUpdate() {
13. showLoadingDialog(“检测更新中…”);
14. version = AppUpdateUtil.getAppVersionCode(this);//检查当前版本号
15. // 调用方法，，，接口的具体实现，接收传过来的参数，再调自己的方法，
16. requestAppUpdate(version, new DataRequestListener<UpdateAppBean>() {
17. @Override
18. public void success(UpdateAppBean data) {
19. // 返回的json，getStatus为0时，去下载apk文件,这里是下载apk文件的方法
20. updateApp(data.getData().getApk_url());
21. }
23. @Override
24. public void fail(String msg) {
25. // 返回的json，getStatus为1时，提示：”已是*新版本！”
26. SToast(msg);
27. dismissLoadingDialog();
28. }
29. });
30. }
32. //检查版本号，*次请求(post)，，，UpdateAppBean根据服务器返回生成
33. private void requestAppUpdate(int version, final DataRequestListener<UpdateAppBean> listener) {
34. OkGo.<String>post(Const.HOST_URL + Const.UPDATEAPP).params(“version”, version).execute(new StringCallback() {
35. @Override
36. public void onSuccess(Response<String> response) {
37. Gson gson = new Gson();
38. UpdateAppBean updateAppBean = gson.fromJson(response.body(), UpdateAppBean.class);
39. if (updateAppBean.getStatus() == 0) {
40. listener.success(updateAppBean);
41. } else {
42. listener.fail(updateAppBean.getMsg());
43. }
44. }
46. @Override
47. public void onError(Response<String> response) {
48. listener.fail(“服务器连接失败”);
49. dismissLoadingDialog();
50. }
51. });
52. }
54. //如果有新版本，提示有新的版本，然后下载apk文件
55. private void updateApp(String apk_url) {
56. dismissLoadingDialog();
57. DialogUtils.getInstance().showDialog(this, “发现新的版本，是否下载更新？”,
58. new DialogUtils.DialogListener() {
59. @Override
60. public void positiveButton() {
61. downloadApp(apk_url);
62. }
63. });
64. }
66. //下载apk文件并跳转(第二次请求，get)
67. private void downloadApp(String apk_url) {
68. OkGo.<File>get(apk_url).tag(this).execute(new FileCallback() {
69. @Override
70. public void onSuccess(Response<File> response) {
71. String filePath = response.body().getAbsolutePath();
72. Intent intent = IntentUtil.getInstallAppIntent(mContext, filePath);
73. // 测试过这里必须用startactivity，不能用stratactivityforresult
74. mContext.startActivity(intent);
75. dismissLoadingDialog();
76. mDownloadDialog.dismiss();
77. mDownloadDialog=null;
78. }
80. @Override
81. public void downloadProgress(Progress progress) {
82. // showDownloadDialog();
83. // mProgress.setProgress((int) (progress.fraction * 100));
84. if (mDownloadDialog == null) {
85. // 构造软件下载对话框
86. AlertDialog.Builder builder = new AlertDialog.Builder(mContext);
87. builder.setTitle(“正在更新”);
88. // 给下载对话框增加进度条
89. final LayoutInflater inflater = LayoutInflater.from(mContext);
90. View v = inflater.inflate(R.layout.item_progress, null);
91. mProgress = (ProgressBar) v.findViewById(R.id.update_progress);
92. builder.setView(v);
93. mDownloadDialog = builder.create();
94. mDownloadDialog.setCancelable(false);
95. mDownloadDialog.show();
96. }
97. mProgress.setProgress((int) (progress.fraction * 100));
98. }
99. });
100. }

2.2 DataRequestListener：

1. public interface DataRequestListener<T> {
2. //请求成功
3. void success(T data);
4. //请求失败
5. void fail(String msg);
6. }

2.3 AppUpdateUtil：

1. /**
2. * 获取App版本码
3. *
4. * @param context 上下文
5. * @return App版本码
6. */
7. public static int getAppVersionCode(Context context) {
8. return getAppVersionCode(context, context.getPackageName());
9. }

2.4 IntentUtil：

1. public class IntentUtil {
3. /**
4. * 获取安装App(支持7.0)的意图
5. *
6. * @param context
7. * @param filePath
8. * @return
9. */
10. public static Intent getInstallAppIntent(Context context, String filePath) {
11. //apk文件的本地路径
12. File apkfile = new File(filePath);
13. if (!apkfile.exists()) {
14. return null;
15. }
16. Intent intent = new Intent(Intent.ACTION_VIEW);
17. Uri contentUri = FileUtil.getUriForFile(context, apkfile);
18. intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
19. if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
20. intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
21. }
22. intent.setDataAndType(contentUri, “application/vnd.android.package-archive”);
23. return intent;
24. }

2.5 FileUtil：

1. /**
2. * 将文件转换成uri(支持7.0)
3. *
4. * @param mContext
5. * @param file
6. * @return
7. */
8. public static Uri getUriForFile(Context mContext, File file) {
9. Uri fileUri = null;
10. if (Build.VERSION.SDK_INT >= 24) {
11. fileUri = FileProvider.getUriForFile(mContext, mContext.getPackageName() + “.fileprovider”, file);
12. } else {
13. fileUri = Uri.fromFile(file);
14. }
15. return fileUri;
16. }