获取 Android 手机中安装的所有应用程序列表的不同方法

在本文中，我们将显示您的 Android 手机上所有已安装应用程序的列表。所以在这里我们将学习如何以三种不同的方式实现该功能。请注意，我们将使用Java语言来实现这个项目。

分步实施

第 1 步：创建一个新项目

要在 Android Studio 中创建新项目，请参阅如何在 Android Studio 中创建/启动新项目。请注意，选择Java作为编程语言。

步骤 2：使用 activity_main.xml 文件

导航到app > res > layout > activity_main.xml并将以下代码添加到该文件中。下面是activity_main.xml文件的代码。

方法一

转到主活动。 Java文件，参考如下代码。下面是MainActivity的代码。 Java文件。代码中添加了注释以更详细地理解代码。

Java

import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
  
import androidx.appcompat.app.AppCompatActivity;
  
import java.util.List;
  
public class MainActivity extends AppCompatActivity {
  
    ListView listView;
    TextView text;
  
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
          
        // initialise layout
        listView = findViewById(R.id.listview);
        text = findViewById(R.id.totalapp);
    }
  
    public void getallapps(View view) {
        // get list of all the apps installed 
        List infos = getPackageManager().getInstalledApplications(PackageManager.GET_META_DATA);
        // create a list with sze of total number of apps 
        String[] apps = new String[infos.size()];
        int i = 0;
        // add all the app name in string list
        for (ApplicationInfo info : infos) {
            apps[i] = info.packageName;
            i++;
        }
        // set all the apps name in list view
        listView.setAdapter(new ArrayAdapter(MainActivity.this, android.R.layout.simple_list_item_1, apps));
        // write total count of apps available. 
        text.setText(infos.size() + " Apps are installed");
    }
  
    @Override
    protected void onStart() {
        super.onStart();
  
    }
}

输出：

方法二

转到主活动。 Java文件，参考如下代码。下面是 MainActivity 的代码。 Java文件。代码中添加了注释以更详细地理解代码。

Java

import android.content.pm.PackageInfo;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
  
import androidx.appcompat.app.AppCompatActivity;
  
import java.util.List;
  
public class MainActivity extends AppCompatActivity {
      
    ListView listView;
    TextView text;
  
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
          
        // initialise layout
        listView = findViewById(R.id.listview);
        text = findViewById(R.id.totalapp);
    }
  
    public void getallapps(View view) {
        // get list of all the apps installed
        List packList = getPackageManager().getInstalledPackages(0);
        String[] apps = new String[packList.size()];
        for (int i = 0; i < packList.size(); i++) {
            PackageInfo packInfo = packList.get(i);
            apps[i] = packInfo.applicationInfo.loadLabel(getPackageManager()).toString();
        }
        // set all the apps name in list view
        listView.setAdapter(new ArrayAdapter(MainActivity.this, android.R.layout.simple_list_item_1, apps));
        // write total count of apps available.
        text.setText(packList.size() + " Apps are installed");
    }
  
    @Override
    protected void onStart() {
        super.onStart();
  
    }
}

输出：

方法三

转到主活动。 Java文件，参考如下代码。下面是MainActivity的代码。 Java文件。代码中添加了注释以更详细地理解代码。

Java

import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.content.res.Resources;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
  
import androidx.appcompat.app.AppCompatActivity;
  
import java.util.ArrayList;
import java.util.List;
  
public class MainActivity extends AppCompatActivity {
  
    ListView listView;
    TextView text;
  
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
  
        // initialise layout
        listView = findViewById(R.id.listview);
        text = findViewById(R.id.totalapp);
    }
  
  
    public void getallapps(View view) throws PackageManager.NameNotFoundException {
        final Intent mainIntent = new Intent(Intent.ACTION_MAIN, null);
        mainIntent.addCategory(Intent.CATEGORY_LAUNCHER);
  
        // get list of all the apps installed
        List ril = getPackageManager().queryIntentActivities(mainIntent, 0);
        List componentList = new ArrayList();
        String name = null;
        int i = 0;
  
        // get size of ril and create a list
        String[] apps = new String[ril.size()];
        for (ResolveInfo ri : ril) {
            if (ri.activityInfo != null) {
                // get package
                Resources res = getPackageManager().getResourcesForApplication(ri.activityInfo.applicationInfo);
                // if activity label res is found
                if (ri.activityInfo.labelRes != 0) {
                    name = res.getString(ri.activityInfo.labelRes);
                } else {
                    name = ri.activityInfo.applicationInfo.loadLabel(
                            getPackageManager()).toString();
                }
                apps[i] = name;
                i++;
            }
        }
        // set all the apps name in list view
        listView.setAdapter(new ArrayAdapter(MainActivity.this, android.R.layout.simple_list_item_1, apps));
        // write total count of apps available.
        text.setText(ril.size() + " Apps are installed");
    }
  
    @Override
    protected void onStart() {
        super.onStart();
  
    }
}

输出：