Android 12去除安装应用时的“未知应用来源”提示

一、概述

在Android 12的系统中预装了一个第三方的应用商店，但是首次安装应用的时候会提示该商店是未知来源，需要用户跳转到系统设置去给该应用设置成可安装应用。虽然该提示只是在首次安装应用的时候才提示，但是对一个产品来说如果预装的商店弹出此提示，还是会让用户对产品有所怀疑，所以需要把该提示去掉。

二、解决方案

跟踪代码发现，弹窗是中弹出的，在PackageInstallerActivity的OnResume函数中会调用checkIfAllowedAndInitiateInstall()函数去判断是否允许安装

 @Override
    protected void onResume() {
        ();

        if (mLocalLOGV) (TAG, "onResume(): mAppSnippet=" + mAppSnippet);

        if (mAppSnippet != null) {
            // load dummy layout with OK button disabled until we override this layout in
            // startInstallConfirm
            bindUi();
            checkIfAllowedAndInitiateInstall();
        }

        if (mOk != null) {
            (mEnableOk);
        }
    }

在checkIfAllowedAndInitiateInstall（）函数中调用isInstallRequestFromUnknownSource(getIntent())判断，发起安装的应用是否是未知来源，如果是则返回true，如果否则返回false

 private void checkIfAllowedAndInitiateInstall() {
        // Check for install apps user restriction first.
        final int installAppsRestrictionSource = (
                UserManager.DISALLOW_INSTALL_APPS, ());
        if ((installAppsRestrictionSource & UserManager.RESTRICTION_SOURCE_SYSTEM) != 0) {
            if (mLocalLOGV) (TAG, "install not allowed: " + UserManager.DISALLOW_INSTALL_APPS);
            showDialogInner(DLG_INSTALL_APPS_RESTRICTED_FOR_USER);
            return;
        } else if (installAppsRestrictionSource != UserManager.RESTRICTION_NOT_SET) {
            if (mLocalLOGV) {
                (TAG, "install not allowed by admin; showing "
                        + Settings.ACTION_SHOW_ADMIN_SUPPORT_DETAILS);
            }
            startActivity(new Intent(Settings.ACTION_SHOW_ADMIN_SUPPORT_DETAILS));
            finish();
            return;
        }

        if (mAllowUnknownSources || !isInstallRequestFromUnknownSource(getIntent())) {
            if (mLocalLOGV) (TAG, "install allowed");
            initiateInstall();
        } else {
            // Check for unknown sources restrictions.
            final int unknownSourcesRestrictionSource = (
                    UserManager.DISALLOW_INSTALL_UNKNOWN_SOURCES, ());
            final int unknownSourcesGlobalRestrictionSource = (
                    UserManager.DISALLOW_INSTALL_UNKNOWN_SOURCES_GLOBALLY, ());
            final int systemRestriction = UserManager.RESTRICTION_SOURCE_SYSTEM
                    & (unknownSourcesRestrictionSource | unknownSourcesGlobalRestrictionSource);
            if (systemRestriction != 0) {
                if (mLocalLOGV) (TAG, "Showing DLG_UNKNOWN_SOURCES_RESTRICTED_FOR_USER");
                showDialogInner(DLG_UNKNOWN_SOURCES_RESTRICTED_FOR_USER);
            } else if (unknownSourcesRestrictionSource != UserManager.RESTRICTION_NOT_SET) {
                startAdminSupportDetailsActivity(UserManager.DISALLOW_INSTALL_UNKNOWN_SOURCES);
            } else if (unknownSourcesGlobalRestrictionSource != UserManager.RESTRICTION_NOT_SET) {
                startAdminSupportDetailsActivity(
                        UserManager.DISALLOW_INSTALL_UNKNOWN_SOURCES_GLOBALLY);
            } else {
                handleUnknownSources();
            }
        }
    }

所以目前解决方案就是在isInstallRequestFromUnknownSource（）函数中，加入要过滤的应用商店的包名判断，如果包名匹配则直接返回false

    private boolean isInstallRequestFromUnknownSource(Intent intent) {
        if (mCallingPackage != null && (
                Intent.EXTRA_NOT_UNKNOWN_SOURCE, false)) {
            if (mSourceInfo != null) {
                if (( & ApplicationInfo.PRIVATE_FLAG_PRIVILEGED)
                        != 0) {
                    // Privileged apps can bypass unknown sources check if they want.
                    return false;
                }
            }
        }
        // modify start
        if(mOriginatingPackage != null && "".equals(mOriginatingPackage)){
            return false;
        }
        //modify end
        return true;
    }