Android 安裝apk的方法

     傳入apk的絕對路徑，自動安裝apk的方法：

 private void installApk(String path) {
        File file = new File(path);
        if (file.exists()) {
            Intent installApkIntent = new Intent();
            installApkIntent.setAction(Intent.ACTION_VIEW);
            installApkIntent.addCategory(Intent.CATEGORY_DEFAULT);
            installApkIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
               //適配8.0需要有權限
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
        boolean hasInstallPermission = getPackageManager().canRequestPackageInstalls();
  if (hasInstallPermission) {
                    //安裝應用
installApkIntent.setDataAndType(FileProvider.getUriForFile(getApplicationContext(), AppUtils.getPackageName(this) + ".file_provider", file), "application/vnd.android.package-archive");
  installApkIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
   if (getPackageManager().queryIntentActivities(installApkIntent, 0).size() > 0) {
                        startActivity(installApkIntent);
                    }
} else {
   //跳轉至“安裝未知應用”權限界面，引導用戶開啓權限
   Uri selfPackageUri = Uri.parse("package:" + this.getPackageName());
   Intent intent = new Intent(Settings.ACTION_MANAGE_UNKNOWN_APP_SOURCES, selfPackageUri);
                    startActivityForResult(intent, REQUEST_CODE_UNKNOWN_APP);
                }
 } else {
  if (Build.VERSION.SDK_INT > Build.VERSION_CODES.M) {                  installApkIntent.setDataAndType(FileProvider.getUriForFile(getApplicationContext(), AppUtils.getPackageName(this) + ".file_provider", file), "application/vnd.android.package-archive");
   installApkIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
 } else {
  installApkIntent.setDataAndType(Uri.fromFile(file), "application/vnd.android.package-archive");
       }
   if (getPackageManager().queryIntentActivities(installApkIntent, 0).size() > 0) {
                    startActivity(installApkIntent);
                }
            }
        }
    }