如何在android中使用图标和复选框列出所有已安装的应用程序
您好如何在android中使用图标和复选框列出所有已安装的应用程序,android,android-listview,Android,Android Listview,您好stackoverflow我正在尝试开发一个应用程序,它可以显示所有已安装应用程序的列表,并带有图标、名称和复选框,下面是我的代码 activity\u main.xml <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orienta
stackoverflow
我正在尝试开发一个应用程序,它可以显示所有已安装应用程序的列表,并带有图标、名称和复选框
,下面是我的代码
activity\u main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<ListView
android:id="@android:id/list"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</LinearLayout>
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_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" />
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:gravity="center_vertical"
android:orientation="vertical"
android:paddingLeft="5dp" >
<TextView
android:id="@+id/app_name"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:textStyle="bold" />
<TextView
android:id="@+id/app_paackage"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical" />
</LinearLayout>
<CheckBox
android:id="@+id/cb_app"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
MainActivity.java
public class MainActivity extends ListActivity {
private PackageManager packageManager = null;
private List<ApplicationInfo> applist = null;
private ApplicationAdapter listadaptor = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
packageManager = getPackageManager();
new LoadApplications().execute();
}
@Override
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 (null != intent) {
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 (null != packageManager.getLaunchIntentForPackage(info.packageName)) {
applist.add(info);
}
} catch (Exception e) {
e.printStackTrace();
}
}
return applist;
}
private class LoadApplications extends AsyncTask<Void, Void, Void> {
private ProgressDialog progress = null;
@Override
protected Void doInBackground(Void... params) {
applist = checkForLaunchIntent(packageManager.getInstalledApplications(PackageManager.GET_META_DATA));
listadaptor = new ApplicationAdapter(MainActivity.this,
R.layout.row, applist);
return null;
}
@Override
protected void onCancelled() {
super.onCancelled();
}
@Override
protected void onPostExecute(Void result) {
setListAdapter(listadaptor);
progress.dismiss();
super.onPostExecute(result);
}
@Override
protected void onPreExecute() {
progress = ProgressDialog.show(MainActivity.this, null,
"Loading application info...");
super.onPreExecute();
}
@Override
protected void onProgressUpdate(Void... values) {
super.onProgressUpdate(values);
}
}
}
import java.util.List;
import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
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 ApplicationAdapter extends ArrayAdapter<ApplicationInfo> {
private List<ApplicationInfo> appsList = null;
private Context context;
private PackageManager packageManager;
public ApplicationAdapter(Context context, int textViewResourceId,
List<ApplicationInfo> appsList) {
super(context, textViewResourceId, appsList);
this.context = context;
this.appsList = appsList;
packageManager = context.getPackageManager();
}
@Override
public int getCount() {
return ((null != appsList) ? appsList.size() : 0);
}
@Override
public ApplicationInfo getItem(int position) {
return ((null != appsList) ? appsList.get(position) : null);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
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.row, null);
}
ApplicationInfo data = appsList.get(position);
if (null != data) {
TextView appName = (TextView) view.findViewById(R.id.app_name);
TextView packageName = (TextView) view.findViewById(R.id.app_paackage);
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;
}
问题是每当我勾选一个复选框,并滚动滚动窗口中的其他框复选框
时,就会选择。请帮我解开这个谜
谢谢。发生这种情况的原因是您的视图被重复使用,但您没有重置getView
中复选框的状态
我建议你这样做:
import java.util.List;
import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
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 ApplicationAdapter extends ArrayAdapter<ApplicationInfo> {
private List<ApplicationInfo> appsList = null;
private Context context;
private PackageManager packageManager;
private ArrayList<Boolean> checkList = new ArrayList<Boolean>();
public ApplicationAdapter(Context context, int textViewResourceId,
List<ApplicationInfo> appsList) {
super(context, textViewResourceId, appsList);
this.context = context;
this.appsList = appsList;
packageManager = context.getPackageManager();
for (int i = 0; i < appsList.size(); i++) {
checkList.add(false);
}
}
@Override
public int getCount() {
return ((null != appsList) ? appsList.size() : 0);
}
@Override
public ApplicationInfo getItem(int position) {
return ((null != appsList) ? appsList.get(position) : null);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
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.row, null);
}
ApplicationInfo data = appsList.get(position);
if (null != data) {
TextView appName = (TextView) view.findViewById(R.id.app_name);
TextView packageName = (TextView) view.findViewById(R.id.app_paackage);
ImageView iconview = (ImageView) view.findViewById(R.id.app_icon);
CheckBox checkBox = (CheckBox) view.findViewById(R.id.cb_app);
checkBox.setTag(Integer.valueOf(position)); // set the tag so we can identify the correct row in the listener
checkBox.setChecked(checkList.get(position); // set the status as we stored it
checkBox.setOnCheckedChangeListener(mListener); // set the listener
appName.setText(data.loadLabel(packageManager));
packageName.setText(data.packageName);
iconview.setImageDrawable(data.loadIcon(packageManager));
}
return view;
}
OnCheckedChangeListener mListener = new OnCheckedChangeListener() {
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
checkList.set((Integer)buttonView.getTag(),isChecked); // get the tag so we know the row and store the status
}
};
}
import java.util.List;
导入android.content.Context;
导入android.content.pm.ApplicationInfo;
导入android.content.pm.PackageManager;
导入android.view.LayoutInflater;
导入android.view.view;
导入android.view.ViewGroup;
导入android.widget.ArrayAdapter;
导入android.widget.ImageView;
导入android.widget.TextView;
公共类应用程序适配器扩展了ArrayAdapter{
私有列表appsList=null;
私人语境;
专用软件包管理器软件包管理器;
私有ArrayList检查表=新建ArrayList();
公共应用程序适配器(上下文,int textViewResourceId,
列表(应用列表){
超级(上下文、textViewResourceId、appsList);
this.context=上下文;
this.appsList=appsList;
packageManager=context.getPackageManager();
对于(int i=0;i
基本上,有一个存储每个复选框(对应于您的数据)状态的数组列表。例如:当您单击位于位置1
的复选框时,checkList.get(1)
为true
由于视图被重复使用,您需要存储每个复选框相对于其位置的状态。例如,位置x
处的复选框是否被选中。然后,当您对位置x
执行getView()
操作时,您可以使用存储的状态来设置正确的选中值
更新使用false
值初始化检查表。您应该在sqlite中维护已访问的项目列表
checkBox.setOnCheckedChangeListener(新建CompoundButton.OnCheckedChangeListener()
{
@凌驾
检查更改后的公共无效(复合按钮视图,布尔值已检查)
{
如果(已检查)
{
//执行逻辑
checkList.set((Integer)buttonView.getTag(),isChecked);//获取标记以便我们知道行并存储状态
int position=(int)按钮view.getTag();
Toast.makeText(context,String.valueOf(position),Toast.LENGTH_LONG.show();
布尔结果=help.insertContact(String.valueOf(position));
系统输出打印项次(结果);
}
}
});
如果(计数=0){
计数++;
ids=新的ArrayList();
ids=help.getAllCotacts();
如果(ids.size()>0){
对于(int i=0;i
更新了我的答案。由于视图被重复使用,您需要存储每个复选框相对于其位置的状态。即,位置x
处的复选框是否被选中。然后,当您执行getView()时
对于位置x
使用存储状态设置正确的检查值。异常,强制关闭
10-23 10:55:38.613:E/AndroidRuntime(2663):在com.example.listalInstalledApps.ApplicationAdapter.getView(ApplicationAdapter.ja)中
checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener()
{
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked)
{
if ( isChecked )
{
// perform logic
checkList.set((Integer) buttonView.getTag(), isChecked); // get the tag so we know the row and store the status
int position = (int) buttonView.getTag();
Toast.makeText(context,String.valueOf(position),Toast.LENGTH_LONG).show();
boolean result= help.insertContact(String.valueOf(position));
System.out.println(result);
}
}
});
if (count == 0){
count++;
ids = new ArrayList<String>();
ids = help.getAllCotacts();
if (ids.size() > 0) {
for (int i = 0; i < ids.size(); i++) {
checkBox.setChecked(checkList.set(Integer.parseInt(ids.get(i)),true));
}
Toast.makeText(context, String.valueOf(ids.get(0)), Toast.LENGTH_LONG).show();
} else {
Toast.makeText(context, "No values in DB", Toast.LENGTH_LONG).show();
}
}