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我正在尝试为我的应用程序创建一个带有复选框的过滤功能。我已经填充了已安装应用程序的列表,我只想过滤掉其中的几个。我的想法是获取那些被选中的复选框并将其存储到一个数组中。之后,将其显示回列表视图。

例子:

对于这个例子,我只想在点击提交按钮时列出地图和相机。有谁知道我应该怎么做才能实现这一目标?由于我对android studio的了解,我目前一无所知。

这是我的代码。

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">

<ListView
    android:id="@+id/android:list"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">
</ListView>

</LinearLayout>

activity_list_app.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">

<ImageView
    android:id="@+id/app_icon"
    android:layout_width="50dp"
    android:layout_height="50dp"
    android:padding="3dp"
    android:scaleType="centerCrop"
    android:contentDescription="@null"/>

<LinearLayout
    android:layout_width="240dp"
    android:layout_height="wrap_content"
    android:gravity="center|center_vertical"
    android:orientation="vertical"
    android:padding="5dp">

    <TextView
        android:id="@+id/app_name"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:textStyle="bold"
        android:layout_gravity="left" />

    <TextView
        android:id="@+id/app_package"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:layout_gravity="left" />

</LinearLayout>

<CheckBox
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/checkbox" />

MainActivity.java

import android.app.ListActivity;
import android.app.ProgressDialog;
import android.content.ActivityNotFoundException;
import android.content.Intent;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;
import android.widget.CheckedTextView;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends ListActivity{

private PackageManager packageManager = null;
private List<ApplicationInfo> applist = null;
private AppAdapter listadapter = null;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    packageManager = getPackageManager();
    //ListView listview= getListView();
    new LoadApplications().execute();
}

protected void onListItemClick(ListView l, View v, int position, long id){
    super.onListItemClick(l, v, position, id);
    ApplicationInfo app = applist.get(position);
    try{
        Intent intent = packageManager.getLaunchIntentForPackage(app.packageName);

        if(intent != null){
            startActivity(intent);
        }
    }catch(ActivityNotFoundException e){
        Toast.makeText(MainActivity.this,e.getMessage(), Toast.LENGTH_LONG).show();
    }catch(Exception e){
        Toast.makeText(MainActivity.this,e.getMessage(), Toast.LENGTH_LONG).show();
    }
}

private List<ApplicationInfo> checkForLaunchIntent(List<ApplicationInfo> list){
    ArrayList<ApplicationInfo> appList = new ArrayList<ApplicationInfo>();
    for(ApplicationInfo info : list){
        try{
            if(packageManager.getLaunchIntentForPackage(info.packageName)!=null){
                appList.add(info);
            }
        }catch(Exception e){
            e.printStackTrace();
        }
    }
    return appList;
}

private class LoadApplications extends AsyncTask<Void, Void, Void>{
    private ProgressDialog progress = null;
    protected Void doInBackground(Void... params){
        applist = checkForLaunchIntent(packageManager.getInstalledApplications(PackageManager.GET_META_DATA));
        listadapter = new AppAdapter(MainActivity.this, R.layout.activity_list_app, applist);
        return null;
    }
    protected void onPostExecute(Void result){
        setListAdapter(listadapter);
        progress.dismiss();
        super.onPostExecute(result);
    }
    protected void onPreExecute(){
        progress = ProgressDialog.show(MainActivity.this, null, "Loading apps info...");
        super.onPreExecute();
    }
}
}

AppAdapter.java

import java.util.List;

import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.util.SparseBooleanArray;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;

public class AppAdapter extends ArrayAdapter<ApplicationInfo>{

private List<ApplicationInfo> appList;
private Context context;
private PackageManager packageManager;

public AppAdapter(Context context, int resource, List<ApplicationInfo> objects){
    super(context, resource,objects);

    this.context = context;
    this.appList= objects;
    packageManager= context.getPackageManager();
}

public View getView(int position, View convertView, ViewGroup parent){
    View view = convertView;
    if(null == view){
        LayoutInflater layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view = layoutInflater.inflate(R.layout.activity_list_app,null);
    }

    ApplicationInfo data = appList.get(position);

    if(null != data){
        TextView appName = (TextView) view.findViewById(R.id.app_name);
        TextView packageName = (TextView) view.findViewById(R.id.app_package);
        ImageView iconView = (ImageView) view.findViewById(R.id.app_icon);

        appName.setText(data.loadLabel(packageManager));
        packageName.setText(data.packageName);
        iconView.setImageDrawable(data.loadIcon(packageManager));
    }
    return view;
}

public int getCount(){
    return((null != appList) ? appList.size() : 0);
}
public ApplicationInfo getItem(int position){
    return((null != appList) ? appList.get(position): null);
}
public long getItemId(int position) {
    return position;
}
}
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