Android開發系列_手把手開發APP_007_版本號信息顯示

package com.example.mobilesafe.chartper1;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.os.Bundle;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.android.material.snackbar.Snackbar;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;
import android.view.View;
import android.widget.TextView;
import com.example.mobilesafe.R;
public class SplashActivity extends AppCompatActivity {
    private TextView tw;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_splash);
        init();
    }
    public void init(){
        tw = findViewById(R.id.splash_textview);
        //獲得版本號信息
        try {
            PackageInfo packageInfo = getPackageManager().getPackageInfo(getPackageName(), 0);
            tw.setText("當前版本:V" + packageInfo.versionName);
        } catch (PackageManager.NameNotFoundException e1) {
            e1.printStackTrace();
            tw.setText("當前版本：V");
        }
    }
}

layout

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/launch_bg"
    android:gravity="center">
    <TextView
        android:id="@+id/tv_version"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="230dp"
        android:textColor="@android:color/white"
        android:textSize="14sp" />
</RelativeLayout>