Kotlin示例：

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.act_signin)

    packageManager.getPackageInfo(packageName, PackageManager.GET_ACTIVITIES).apply {
        findViewById<TextView>(R.id.text_version_name).text = versionName
        findViewById<TextView>(R.id.text_version_code).text =
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) "$longVersionCode" else "$versionCode"
    }

    packageManager.getApplicationInfo(packageName, 0).apply{
        findViewById<TextView>(R.id.text_build_date).text =
            SimpleDateFormat("yy-MM-dd hh:mm").format(java.io.File(sourceDir).lastModified())
    }
}

由于我只需要获取版本代码并检查应用程序是否更新，如果是，我必须启动play商店以获取更新的应用程序。我是这样做的。

public class CheckForUpdate {

    public static final String ACTION_APP_VERSION_CHECK = "app-version-check";

    public static void launchPlayStoreApp(Context context)
    {
        // getPackageName() from Context or Activity object
        final String appPackageName = context.getPackageName();
        try {
            context.startActivity(new Intent(Intent.ACTION_VIEW,
                                  Uri.parse("market://details?id=" + appPackageName)));
        }
        catch (android.content.ActivityNotFoundException anfe) {
            context.startActivity(new Intent(Intent.ACTION_VIEW,
                                  Uri.parse("https://play.google.com/store/apps/details?id=" +
                                             appPackageName)));
        }
    }

    public static int getRemoteVersionNumber(Context context)
    {
        int versionCode = 0;
        try {
            PackageInfo pInfo = context.getPackageManager().getPackageInfo(context.getPackageName(), 0);
            String version = pInfo.versionName;
            versionCode = pInfo.versionCode;
        }
        catch (PackageManager.NameNotFoundException e) {
            e.printStackTrace();
        }
        return versionCode;
    }
}

然后，我通过创建一个util类，使用共享首选项保存了版本代码。

public class PreferenceUtils {

    // This is for version code
    private  final String APP_VERSION_CODE = "APP_VERSION_CODE";
    private  SharedPreferences sharedPreferencesAppVersionCode;
    private SharedPreferences.Editor editorAppVersionCode;
    private static Context mContext;

    public PreferenceUtils(Context context)
    {
        this.mContext = context;
        // This is for the app versioncode
        sharedPreferencesAppVersionCode = mContext.getSharedPreferences(APP_VERSION_CODE,MODE_PRIVATE);
        editorAppVersionCode = sharedPreferencesAppVersionCode.edit();
    }

    public void createAppVersionCode(int versionCode) {

        editorAppVersionCode.putInt(APP_VERSION_CODE, versionCode);
        editorAppVersionCode.apply();
    }

    public int getAppVersionCode()
    {
        return sharedPreferencesAppVersionCode.getInt(APP_VERSION_CODE,0); // As the default version code is 0
    }
}

private String GetAppVersion() {
    try {
        PackageInfo _info = mContext.getPackageManager().getPackageInfo(mContext.getPackageName(), 0);
        return _info.versionName;
    }
    catch (PackageManager.NameNotFoundException e) {
        e.printStackTrace();
        return "";
    }
}

private int GetVersionCode() {
    try {
        PackageInfo _info = mContext.getPackageManager().getPackageInfo(mContext.getPackageName(), 0);
        return _info.versionCode;
    }
    catch (PackageManager.NameNotFoundException e) {
        e.printStackTrace();
        return -1;
    }
}

如果您使用的是PhoneGap，请创建自定义PhoneGa插件：

在应用程序包中创建新类：

package com.Demo; //replace with your package name

import org.json.JSONArray;

import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;

import com.phonegap.api.Plugin;
import com.phonegap.api.PluginResult;
import com.phonegap.api.PluginResult.Status;

public class PackageManagerPlugin extends Plugin {

    public final String ACTION_GET_VERSION_NAME = "GetVersionName";

    @Override
    public PluginResult execute(String action, JSONArray args, String callbackId) {
        PluginResult result = new PluginResult(Status.INVALID_ACTION);
        PackageManager packageManager = this.ctx.getPackageManager();

        if(action.equals(ACTION_GET_VERSION_NAME)) {
            try {
                PackageInfo packageInfo = packageManager.getPackageInfo(
                                              this.ctx.getPackageName(), 0);
                result = new PluginResult(Status.OK, packageInfo.versionName);
            }
            catch (NameNotFoundException nnfe) {
                result = new PluginResult(Status.ERROR, nnfe.getMessage());
            }
        }

        return result;
    }
}

在plugins.xml中，添加以下行：

<plugin name="PackageManagerPlugin" value="com.Demo.PackageManagerPlugin" />

在deviceready事件中，添加以下代码：

var PackageManagerPlugin = function() {

};
PackageManagerPlugin.prototype.getVersionName = function(successCallback, failureCallback) {
    return PhoneGap.exec(successCallback, failureCallback, 'PackageManagerPlugin', 'GetVersionName', []);
};
PhoneGap.addConstructor(function() {
    PhoneGap.addPlugin('packageManager', new PackageManagerPlugin());
});

然后，您可以通过执行以下操作获取versionName属性：

window.plugins.packageManager.getVersionName(
    function(versionName) {
        //do something with versionName
    },
    function(errorMessage) {
        //do something with errorMessage
    }
);

源自这里和这里。

始终使用try-catch块：

String versionName = "Version not found";

try {
    versionName = context.getPackageManager().getPackageInfo(context.getPackageName(), 0).versionName;
    Log.i(TAG, "Version Name: " + versionName);
} catch (NameNotFoundException e) {
    // TODO Auto-generated catch block
    Log.e(TAG, "Exception Version Name: " + e.getLocalizedMessage());
}

PackageInfo pinfo = null;
try {
    pinfo = getPackageManager().getPackageInfo(getPackageName(), 0);
}
catch (PackageManager.NameNotFoundException e) {
    e.printStackTrace();
}
int versionNumber = pinfo.versionCode;
String versionName = pinfo.versionName;