Android基础_常见Adapter/ExpandListView/Dialog/PopupWindow/自定义AlertDialog/单元测试/转移文件到SD卡(四)

Adapter接口

public interface Adapter {    void registerDataSetObserver(DataSetObserver observer);    void unregisterDataSetObserver(DataSetObserver observer);    int getCount();       Object getItem(int position);    long getItemId(int position);    View getView(int position, View convertView, ViewGroup parent);    static final int IGNORE_ITEM_VIEW_TYPE = AdapterView.ITEM_VIEW_TYPE_IGNORE;    int getItemViewType(int position);    int getViewTypeCount();    static final int NO_SELECTION = Integer.MIN_VALUE;     boolean isEmpty();}

BaseAdapter

因为要实现的方法过多,我们一般使用简单的封装类BaseAdapterpublic abstract class BaseAdapter implements ListAdapter, SpinnerAdapter只需要实现四个方法

ArrayAdapter

        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,        android.R.layout.simple_expandable_list_item_1, // 定义每个item的布局        android.R.id.text1, // 定义需要绑定的textview的id        datas;// 填充的一系列数据

SimpleAdapter

        /*List<? extends Map<String, ?>> data,         * extends Map == map的子类         * ? ==Object         * simpleadapter 的子控件一般只能使用系统自带的控件         * 比如Textview-settext ,但非系统的他就不知道该调用什么方法了         * 比如 MyImageView ---         * */         ArrayList<HashMap <String, Object>> datas =new ArrayList<HashMap <String, Object>>() ;         for (int i = 0; i < 10; i++) {             HashMap <String, Object> itemData = new HashMap<String,Object>();             itemData.put("name","袜子"+(i+3));             itemData.put("age",i+3);             itemData.put("gender",i%2==0?"男":"女");             datas.add(itemData);        }SimpleAdapter adapter = new SimpleAdapter(    //进去首先 调用getcount  -- datas.size();    //getView --  第一步:将布局转换成view                      this,                     datas, //数据源,是一个列表数据,他的每一项是HashMAP<String,Obejct>,该HashMap代表的就是我们每一个item的所有数据  第三步:为每个item子控件赋值锁需要的数据源                    R.layout.lv_item_layout, //每个item的布局文件  第一步:将布局转换成view                    new String[]{"name","age","gender"}, // 第四步:先取出item的所有数据 datas.get(position) --->HashMap<String,Object>,即整个item的所有数据的集合object-->再去找子数据                    new int[]{R.id.name,R.id.age,R.id.gender});//代表item内部需要绑定的控件的id  第二步:找到子控件                     lv.setAdapter(adapter);

ExpandListView

1.xml中定义    <ExpandableListView        android:id="@+id/elv"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        /> 2.定义适配器 public class MyAdapter extends BaseExpandableListAdapter {    ArrayList<String> mInitGroupNames;    HashMap<String, ArrayList<String>> mChildrenData;    public ArrayList<String> getmInitGroupNames() {        return mInitGroupNames;    }    public HashMap<String, ArrayList<String>> getmChildrenData() {        return mChildrenData;    }    public MyAdapter(ArrayList<String> initGroupNames,            HashMap<String, ArrayList<String>> hashMap) {        mInitGroupNames = initGroupNames;        mChildrenData = hashMap;    }    @Override    public int getGroupCount() {        return mInitGroupNames.size();    }    @Override    public View getGroupView(int groupPosition, boolean isExpanded,            View convertView, ViewGroup parent) {        TextView tv = null;        if (convertView == null) {            convertView = LayoutInflater.from(parent.getContext()).inflate(                    android.R.layout.simple_list_item_1, parent, false);            tv = (TextView) convertView.findViewById(android.R.id.text1);            convertView.setTag(tv);        } else {            tv = (TextView) convertView.getTag();        }        String groupName = mInitGroupNames.get(groupPosition);        tv.setText(groupName);        return convertView;    }    /*     * 每一个对应的子项的长度 1.首先根据groutposition获取对应的组名 2.根据组名获取对应所有的子参数 3.返回子参数的长度     */    @Override    public int getChildrenCount(int groupPosition) {        String groupName = mInitGroupNames.get(groupPosition);        ArrayList<String> childrenData = mChildrenData.get(groupName);        return childrenData.size();    }    @Override    public View getChildView(int groupPosition, int childPosition,            boolean isLastChild, View convertView, ViewGroup parent) {        TextView tv = null;        if (convertView == null) {            convertView = LayoutInflater.from(parent.getContext()).inflate(                    android.R.layout.simple_list_item_1, parent, false);            tv = (TextView) convertView.findViewById(android.R.id.text1);            convertView.setTag(tv);        } else {            tv = (TextView) convertView.getTag();        }        /*获取子项目的数据bean-->队列         *          * */        String groupName = mInitGroupNames.get(groupPosition);        ArrayList<String> childrenData = mChildrenData.get(groupName);//      根据子项目的索引找到对应的子项目名称        String childName = childrenData.get(childPosition);        tv.setText(childName);        return convertView;    }    @Override    public Object getGroup(int groupPosition) {        // TODO Auto-generated method stub        return null;    }    @Override    public Object getChild(int groupPosition, int childPosition) {        // TODO Auto-generated method stub        return null;    }    @Override    public long getGroupId(int groupPosition) {        // TODO Auto-generated method stub        return 0;    }    @Override    public long getChildId(int groupPosition, int childPosition) {        // TODO Auto-generated method stub        return 0;    }    @Override    public boolean hasStableIds() {        // TODO Auto-generated method stub        return false;    }    @Override    public boolean isChildSelectable(int groupPosition, int childPosition) {        // TODO Auto-generated method stub        return true;    }} 3. ExpandableListView elv = (ExpandableListView) findViewById(R.id.elv);        final MyAdapter dapter = new MyAdapter(initGroupNames(),                initChildrenData());        elv.setAdapter(dapter);        

Dialog

public void click01(View v) {        /* 1.使用工厂模式 ,创建一个builder         *      titie message setpositive setnegative  可以选择使用         *    1.也可以使用构造器生成一个空白对话框         * 2.生成对话框         * 3.显示对话框         */        AlertDialog.Builder builder = new AlertDialog.Builder(this);        builder.setTitle("提示");        builder.setMessage("你确认要退出吗?");        builder.setPositiveButton("不走不走", new OnClickListener() {            @Override            public void onClick(DialogInterface dialog, int which) {                tip("不走不走");            }        });        builder.setNegativeButton("拜拜了您呐", new OnClickListener() {            @Override            public void onClick(DialogInterface dialog, int which) {                tip("拜拜了您呐");            }        });             AlertDialog dialog = builder.create();        dialog.show();    }    /*链式调用*/    public void click02(View v) {        new AlertDialog.Builder(this).setTitle("提示").setMessage("你确认要退出吗?")                .setPositiveButton("不走不走", new OnClickListener() {                    @Override                    public void onClick(DialogInterface dialog, int which) {                        tip("不走不走");                    }                }).setNegativeButton("拜拜了您呐", new OnClickListener() {                    @Override                    public void onClick(DialogInterface dialog, int which) {                        tip("拜拜了您呐");                    }                }).create().show();    }    /*     * 1.所有选项,     * 2.默认选中的索引      * 3.每次选择的监听器     */    String[] subjects = new String[]{"语文","数学","英语"};    int mTabIndex=1;    public void click03(View v) {        new AlertDialog.Builder(this)        .setTitle("请选择你最喜欢的学科")        .setSingleChoiceItems(subjects, mTabIndex, new OnClickListener() {            @Override            public void onClick(DialogInterface dialog, int which) {                mTabIndex=which;            }        })        .setPositiveButton("不走不走", new OnClickListener() {                      @Override            public void onClick(DialogInterface dialog, int which) {//              tip(subjects[mTabIndex]);                Toast.makeText(MainActivity.this, subjects[mTabIndex], 0).show();            }        }).setNegativeButton("拜拜了您呐", new OnClickListener() {            @Override            public void onClick(DialogInterface dialog, int which) {                tip("拜拜了您呐");            }        }).create().show();    }    /* 弹出已选择的选项     * 1.遍历flags     * 2.如果某个item为true,那么应该找到对应的数据     * */    boolean[] flags = new boolean[]{false,true,true};    public void click04(View v) {        new AlertDialog.Builder(this)        .setTitle("请选择你最喜欢的学科")        .setMultiChoiceItems(subjects, flags, new OnMultiChoiceClickListener() {            @Override            public void onClick(DialogInterface dialog, int which, boolean isChecked) {                flags[which]=isChecked;            }        })        .setPositiveButton("确定", new OnClickListener() {            @Override            public void onClick(DialogInterface dialog, int which) {                String str = "";                for (int i = 0; i < flags.length; i++) {                    if (flags[i]) {                        str+=subjects[i]+" ";                    }                }                Toast.makeText(MainActivity.this, str, 0).show();            }        })        .create()        .show();    }    /* 3秒后对话框消失     * 1.使用Timer定时器     * 2.dismiss()     * 定时器 timer,定时器内部的操作是在子线程中     * */    public void click05(View v){        final ProgressDialog dialog = new ProgressDialog(this);        dialog.setMessage("角色删除中,请等待...");        dialog.setTitle("尊敬的玩家");        dialog.show();        new Timer().schedule(new TimerTask() {            @Override            public void run() {                dialog.dismiss();            }        }, 3000);    }

PopupWindow

//      pop.showAsDropDown(anchor);  下拉方式展示 anchor在指定的控件下展示//      pop.showAsDropDown(anchor, xoff, yoff) ;yoff,xoff就是偏移量 ,默认左下角//      要使它在正中间,就需要在外面再嵌套一个布局,再使用xoff去调整//      pop.showAtLocation(parent, gravity, x, y)  在指定位置展示    @Override    public void onClick(View v) {        switch(v.getId()){        case R.id.btn:            showPopupWindow();            break;        case R.id.all_tv:            Toast.makeText(this, "第二个子选项", 0).show();            pop.dismiss();            break;        }    }    /*点击外部使pop消失     *  1.给外面的控件一个焦点/ 默认打开pop后内部控件获取焦点     *      pop.setOutsideTouchable(true);如果失效,是因为一个bug,在没有给pop一个背景的情况下就会出现此情况;     *      相对的,无法有时候内部空间爱你无法获取焦点,就需要给他们一个焦点     *  2.  pop.setFocusable(true);     *      pop.setOutsideTouchable(true);     *      pop.setBackgroundDrawable(new BitmapDrawable());     * */    PopupWindow pop;    private void showPopupWindow() {        View contentView = LayoutInflater.from(                MainActivity.this).inflate(R.layout.pop_view, null);        contentView.findViewById(R.id.all_tv).setOnClickListener(this);         pop = new PopupWindow(contentView,                 400,ViewGroup.LayoutParams.WRAP_CONTENT);        pop.setFocusable(true);        pop.setOutsideTouchable(true);        pop.setBackgroundDrawable(new BitmapDrawable());        pop.showAsDropDown(btn, 0, 0);    }    public  void myclick(View v){       }

自定义PopupWindow的布局

    /*     * 1.创建一个只有自定的listview     * 2.获取listview的inflater     * 3.获取listview     * 4.创建一个ArrayAdapter      * 5.lv设置adapter     * 6.创建pop对象     * 7.pop创建按钮和展示方式     * */    PopupWindow pop;    private void showPopupWindow() {        View contentView = LayoutInflater.from(                MainActivity.this).inflate(R.layout.pop_view, null);        ListView lv =(ListView)contentView.findViewById(R.id.lv);        ArrayAdapter<String> adapter =new ArrayAdapter<String>(                this                ,android.R.layout.simple_expandable_list_item_1                ,android.R.id.text1                ,new String[]{"全部","我的微博","周边","特别关注"});        lv.setAdapter(adapter);        lv.setOnItemClickListener(new OnItemClickListener() {            @Override            public void onItemClick(AdapterView<?> parent, View view,                    int position, long id) {                Toast.makeText(MainActivity.this, "onitemclick", 0).show();            }        });        pop=new PopupWindow(contentView,200,ViewGroup.LayoutParams.WRAP_CONTENT);        pop.setFocusable(true);        pop.setOutsideTouchable(true);        pop.setBackgroundDrawable(new BitmapDrawable());        pop.showAsDropDown(btn, 0, 0);    }

自定义AlertDialog

    /*需求:自定义一个对话框     * 1.创建一个class并继承AlertDialog     * 2.弹出一个对话框,需要实现oncreate(),并且在内部调用setconvertview     *      setContentView(R.layout.activity_main);     * 3.在layout中创建一个xml文件     * 4.显示对话框 可以自定义背景/大小  但只能在屏幕的正中间     * */     public class MyAdapter extends AlertDialog {    protected MyAdapter(Context context) {        super(context);    }    @Override    protected void onCreate(Bundle savedInstanceState) {        // TODO Auto-generated method stub        super.onCreate(savedInstanceState);        setContentView(R.layout.my_dialog_layout);          }    MyAdapter dialog = new MyAdapter(this);    dialog.show();}

ListView添加头布局和脚布局

        /*需求:做一个有头部和文本的简单列表         * 1.创建一个简单列表         * 2.创建头部xml,并setheaderview(inflate(xml));         *    注意需要在调用setAdapter方法前调用         * 3.setadapter(adapter);         * ps;涉及到头部的做法有个bug         *  在调用item的监听的时候,点击的对象的索引会+1,因为把头部也视为了一个item         * */View headerView = LayoutInflater.from(this).inflate(R.layout.lv_header_layout, null);            lv.addHeaderView(headerView);            lv.addFooterView(headerView);   

单元测试

public class MockCalcultorDao {    public int add(int x , int y){        return x+y;    }}/*测试类 * 1.创建一个类并继承于AndroidTestCase * 2.创建测试方法testXXX() *      1.创建一个被测试的对象并进行相关操作 *      2.断言真实值和预期值  *          assertEquals(expected,actual); * */public class CalcultorDaoTestCase extends AndroidTestCase {    public void testAdd(){        MockCalcultorDao dao = new MockCalcultorDao();        int actualResult =dao.add(3,5);        assertEquals(8,actualResult);    }}

手机的存储结构

    /*     * 1.手机的内部存储     *      Environment.getDataDirectory();     *      /data该目录下无法直接存储文件     *      * 2.手机的外部存储     *      Environment.getExternalStorageDirecetory();     *      /mnt/sdcard 此为标准路径,也就是说还有别的路径     *      /mnt/storyage01     *      /mount/storyage02     */将某个文件转移到SD卡    /*需求:将某个avi文件转移到sd     * 1.因为sd不一定存在,每次使用sd卡的时候需要判断sd是否安装     *      Environment.getExternalStorageState()     *      MEDIA_MOUNTED已安装的状态     * 2.存在的情况下,在sd卡存储文件     * 3.往文件里模拟下载 模拟创建一个空的文件(只有文件大小,没有内容)     * 4.往sd卡传输数据是敏感操作,需要在manifest声明     *          <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>     *                                                            READ_是写权限              * */    public void startDownload(View v) {        try {            if (Environment.getExternalStorageState().equals(                    Environment.MEDIA_MOUNTED)) {                File file = new File(Environment.getExternalStorageDirectory(),                        "葫芦娃.avi");                FileOutputStream fos = new FileOutputStream(file);                byte[] buffer = new byte[1024*1024];                for (int i = 0; i < 5; i++) {                    fos.write(buffer);                }                fos.close();                Log.v("me", file.exists()+" ");            }        } catch (Exception e) {        }    }