Android開發之listView使用(手機應用列表顯示)
阿新 • • 發佈:2019-02-18
public class MainActivity extends Activity implements OnItemLongClickListener { private ListView lv_main; private List<AppInfo> data; private AppAdapter adapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); //初始化成員變數 lv_main = (ListView) findViewById(R.id.lv_main); data = getAllAppInfos(); adapter = new AppAdapter(); //顯示列表 lv_main.setAdapter(adapter); //給ListView設定item的點選監聽 lv_main.setOnItemClickListener(new OnItemClickListener() { /** * parent : ListView * view : 當前行的item檢視物件 * position : 當前行的下標 */ @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { //提示當前行的應用名稱 String appName = data.get(position).getAppName(); //提示 Toast.makeText(MainActivity.this, appName, 0).show(); } }); //給LitView設定Item的長按監聽 lv_main.setOnItemLongClickListener(this); } class AppAdapter extends BaseAdapter { @Override public int getCount() { return data.size(); } @Override public Object getItem(int position) { return data.get(position); } @Override public long getItemId(int position) { // TODO Auto-generated method stub return 0; } //返回帶資料當前行的Item檢視物件 @Override public View getView(int position, View convertView, ViewGroup parent) { //1. 如果convertView是null, 載入item的佈局檔案 if(convertView==null) { Log.e("TAG", "getView() load layout"); convertView = View.inflate(MainActivity.this, R.layout.item_main, null); } //2. 得到當前行資料物件 AppInfo appInfo = data.get(position); //3. 得到當前行需要更新的子View物件 ImageView imageView = (ImageView) convertView.findViewById(R.id.iv_item_icon); TextView textView = (TextView) convertView.findViewById(R.id.tv_item_name); //4. 給檢視設定資料 imageView.setImageDrawable(appInfo.getIcon()); textView.setText(appInfo.getAppName()); //返回convertView return convertView; } } /* * 得到手機中所有應用資訊的列表 * AppInfo * Drawable icon 圖片物件 * String appName * String packageName */ protected List<AppInfo> getAllAppInfos() { List<AppInfo> list = new ArrayList<AppInfo>(); // 得到應用的packgeManager PackageManager packageManager = getPackageManager(); // 建立一個主介面的intent Intent intent = new Intent(); intent.setAction(Intent.ACTION_MAIN); intent.addCategory(Intent.CATEGORY_LAUNCHER); // 得到包含應用資訊的列表 List<ResolveInfo> ResolveInfos = packageManager.queryIntentActivities( intent, 0); // 遍歷 for (ResolveInfo ri : ResolveInfos) { // 得到包名 String packageName = ri.activityInfo.packageName; // 得到圖示 Drawable icon = ri.loadIcon(packageManager); // 得到應用名稱 String appName = ri.loadLabel(packageManager).toString(); // 封裝應用資訊物件 AppInfo appInfo = new AppInfo(icon, appName, packageName); // 新增到list list.add(appInfo); } return list; } @Override public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) { //刪除當前行 //刪除當前行的資料 data.remove(position); //更新列表 //lv_main.setAdapter(adapter);//顯示列表, 不會使用快取的item的檢視物件 adapter.notifyDataSetChanged();//通知更新列表, 使用所有快取的item的檢視物件 return true; } }
2.AppInfo檔案
public class AppInfo { private Drawable icon;// 應用圖示 private String appName;// 應用名稱 private String packageName;// 包名 public AppInfo(Drawable icon, String appName, String packageName) { super(); this.icon = icon; this.appName = appName; this.packageName = packageName; } public AppInfo() { super(); } public Drawable getIcon() { return icon; } public void setIcon(Drawable icon) { this.icon = icon; } public String getAppName() { return appName; } public void setAppName(String appName) { this.appName = appName; } public String getPackageName() { return packageName; } public void setPackageName(String packageName) { this.packageName = packageName; } @Override public String toString() { return "AppInfo [icon=" + icon + ", appName=" + appName + ", packageName=" + packageName + "]"; } }
3.activity_main檔案
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical" > <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:background="#c610ef" android:gravity="center" android:padding="5dp" android:text="所有應用" android:textColor="#ffffff" android:textSize="25sp" /> <ListView android:id="@+id/lv_main" android:layout_width="match_parent" android:layout_height="fill_parent" > </ListView> </LinearLayout>
4.item_main檔案
<?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="wrap_content" >
<ImageView
android:id="@+id/iv_item_icon"
android:layout_width="60dp"
android:layout_height="60dp"
android:src="@drawable/ic_launcher" />
<TextView
android:id="@+id/tv_item_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="@id/iv_item_icon"
android:layout_centerVertical="true"
android:text="應用名稱"
android:layout_marginLeft="10dp"
android:textSize="20sp"/>
</RelativeLayout>