代码练习

ListView

public class ListActivity extends AppCompatActivity {


    private ListView listView;
    ArrayList<HashMap<String,Object>> listItem;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_list);
        listView = (ListView)findViewById(R.id.listView);
        MyAdapter mAdapter = new MyAdapter(this);
        listView.setAdapter(mAdapter);
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                Log.i("LISTVIEW", "onItemClick:"+i);
            }
        });
    }


    private ArrayList<HashMap<String,Object>> getData() {
        ArrayList<HashMap<String,Object>> listItem =new ArrayList<HashMap<String, Object>>();
        for (int i = 0; i < 30; i++){
            HashMap<String,Object> map =new HashMap<String, Object>();
            map.put("ItemTitle","第"+i+"行");
            map.put("ItemText","这是第"+i+"行");
            listItem.add(map);
        }


        return listItem;
    }
    private class MyAdapter extends BaseAdapter {
       private LayoutInflater inflater;


        public MyAdapter (Context context){
            inflater =LayoutInflater.from(context);


        }


        @Override
        public int getCount() {
            return getData().size();
        }


        @Override
        public Object getItem(int i) {
            return null;
        }


        @Override
        public long getItemId(int i) {
            return 0;
        }


        @Override
        public View getView(int i, View view, ViewGroup viewGroup) {
            ViewHolder viewholder;
            Log.i("LISTVIEW", "getView   "+i+"   view");
            if (view == null){
                view = inflater.inflate(R.layout.item,null);
                viewholder =new ViewHolder();
                viewholder.title =(TextView)view.findViewById(R.id.textView3);
                viewholder.text =(TextView)view.findViewById(R.id.textView4);
                viewholder.btn =(Button)view.findViewById(R.id.button);
                view.setTag(viewholder);
            }else {
                viewholder =(ViewHolder)view.getTag();
            }
            viewholder.title.setText(getData().get(i).get("ItemTitle").toString());
            viewholder.text.setText(getData().get(i).get("ItemText").toString());
            viewholder.btn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    Toast.makeText(ListActivity.this,"点击了按钮",Toast.LENGTH_SHORT).show();
                }
            });
            return view;
        }


    }


    public final class ViewHolder {
        TextView title;
        TextView text;
        Button   btn;
    }
}

注册界面

1. <?xml version="1.0" encoding="utf-8"?>  
2. <TableLayout xmlns:android="http://schemas.android.com/apk/res/android"  
3.     android:layout_width="match_parent"  
4.     android:layout_height="match_parent"  
5.     android:orientation="horizontal"  
6.     android:stretchColumns="1" >  
7.   
8.     <TableRow>  
9.   
10.         <TextView  
11.             android:id="@+id/t1"  
12.             android:layout_width="match_parent"  
13.             android:layout_height="wrap_content"  
14.             android:text="用户名："  
15.             android:textSize="16sp" />  
16.         <!-- selectAllOnFocus="true"  获取焦点而不是将光标移动为文本的开始位置或者末尾位置 -->  
17.   
18.         <EditText  
19.             android:layout_width="match_parent"  
20.             android:layout_height="wrap_content"  
21.             android:hint="请填写登陆账号"  
22.             android:selectAllOnFocus="true" />  
23.     </TableRow>  
24.   
25.     <TableRow>  
26.   
27.         <TextView  
28.             android:layout_width="match_parent"  
29.             android:layout_height="wrap_content"  
30.             android:text="密码："  
31.             android:textSize="16sp" />  
32.   
33.         <EditText  
34.             android:layout_width="match_parent"  
35.             android:layout_height="wrap_content"  
36.             android:inputType="numberPassword" />  
37.     </TableRow>  
38.   
39.     <TableRow>  
40.   
41.         <TextView  
42.             android:layout_width="match_parent"  
43.             android:layout_height="wrap_content"  
44.             android:text="年龄："  
45.             android:textSize="16sp" />  
46.   
47.         <EditText  
48.             android:layout_width="match_parent"  
49.             android:layout_height="wrap_content"  
50.             android:inputType="number"  
51.             android:maxLength="2" />  
52.     </TableRow>  
53.   
54.     <TableRow>  
55.   
56.         <TextView  
57.             android:layout_width="match_parent"  
58.             android:layout_height="wrap_content"  
59.             android:text="出生日期："  
60.             android:textSize="16sp" />  
61.   
62.         <EditText  
63.             android:layout_width="match_parent"  
64.             android:layout_height="wrap_content"  
65.             android:inputType="date" />  
66.     </TableRow>  
67.   
68.     <TableRow>  
69.   
70.         <TextView  
71.             android:layout_width="match_parent"  
72.             android:layout_height="wrap_content"  
73.             android:text="电话："  
74.             android:textSize="16sp" />  
75.   
76.         <EditText  
77.             android:layout_width="match_parent"  
78.             android:layout_height="wrap_content"  
79.             android:inputType="phone"  
80.             android:selectAllOnFocus="true" />  
81.     </TableRow>  
82.   
83.     <Button  
84.         android:layout_width="wrap_content"  
85.         android:layout_height="wrap_content"  
86.         android:text="注册：" />  
87.   
88. </TableLayout> 

View

1. import android.view.View;  
2. import android.view.animation.AlphaAnimation;  
3. import android.view.animation.Animation;  
4. import android.view.animation.Animation.AnimationListener;  
5. import android.view.animation.AnimationSet;  
6. import android.view.animation.LinearInterpolator;  
7. import android.view.animation.RotateAnimation;  
8. import android.view.animation.ScaleAnimation;  
9. import android.view.animation.TranslateAnimation;  
10.   
11.   
12. 
    
13. public class AnimationEffect  
14. {  
15.  
16.     public static void AddAlphaAni(View view)  
17.     {  
18.         AddAlphaAni(view, 0, 1, 1000, Animation.REVERSE, Animation.INFINITE);  
19.     }  
20.       
21.  
22.     public static void AddAlphaAni(View view, float fromAlpha, float toAlpha, long durationMillis, int repeatMode, int repeatCount)  
23.     {  
24.         AlphaAnimation alphaAni = new AlphaAnimation(fromAlpha, toAlpha);  
25.         alphaAni.setDuration(durationMillis);   
26.         alphaAni.setRepeatMode(repeatMode);     
27.         alphaAni.setRepeatCount(repeatCount);   
28.           
29.         view.startAnimation(alphaAni);  
30.     }  
31.       
32.   
33.     public static void setTransAni(View view, int x0, int x1, int y0, int y1, long durationMillis)  
34.     {  
35.         TranslateAnimation transAni = new TranslateAnimation(x0, x1, y0, y1);  
36.         transAni.setDuration(durationMillis);  
37.         transAni.setRepeatMode(Animation.REVERSE);  
38.         transAni.setRepeatCount(Animation.INFINITE);  
39.           
40.         view.startAnimation(transAni);  
41.     }  
42.       
43.   
44.     public static void setRotateAni(View view, float fromDegrees, float toDegrees, long time)  
45.     {  
46.         setRotateAni(view, fromDegrees, toDegrees, time, Animation.REVERSE, Animation.INFINITE, true);  
47.     }  
48.       
49.  
50.     public static void setRotateAni(View view, float fromDegrees, float toDegrees, long durationMillis, int repeatModes, int repeatCount, boolean linear)  
51.     {  
52.         RotateAnimation rotateAni = new RotateAnimation(fromDegrees, toDegrees, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);  
53.         rotateAni.setDuration(durationMillis);  
54.         rotateAni.setRepeatMode(repeatModes);  
55.         rotateAni.setRepeatCount(repeatCount);  
56.           
57.         if(linear) rotateAni.setInterpolator(new LinearInterpolator()); 
58.           
59.         view.startAnimation(rotateAni);  
60.     }  
61.       
62.  
63.     public static void setScaleAni(View V, float fromScale, float toScale, long ANITIME)  
64.     {  
65.         AnimationSet aniSet = new AnimationSet(true);  
66.        
67.         ScaleAnimation scaleAni = new ScaleAnimation(fromScale, toScale, fromScale, toScale, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);  
68.         scaleAni.setDuration(ANITIME);   
69.         aniSet.addAnimation(scaleAni);  
70.           
71.         V.startAnimation(aniSet);       
72.     }  
73.       
74.       
75.     public static void setLightExpendAni(View V)  
76.     {  
77.         AnimationSet aniSet = new AnimationSet(true);  
78.         final int ANITIME = 1200;  
79.           
80.         /  
81.         ScaleAnimation scaleAni = new ScaleAnimation(0.98f, 1.1f, 0.98f, 1.24f, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);  
82.         scaleAni.setDuration(ANITIME);                
83.         scaleAni.setRepeatMode(Animation.RESTART);  
84.         scaleAni.setRepeatCount(Animation.INFINITE); 
85.         aniSet.addAnimation(scaleAni);    
86.           
87.          
88.         AlphaAnimation alphaAni = new AlphaAnimation(1f, 0.05f);  
89.         alphaAni.setDuration(ANITIME);                
90.         alphaAni.setRepeatMode(Animation.RESTART);  
91.         alphaAni.setRepeatCount(Animation.INFINITE);
92.         aniSet.addAnimation(alphaAni);   
93.           
94.         V.startAnimation(aniSet);         
95.     }  
96.       
97.       
98.     public static void setLightAni(final View view)  
99.     {  
100.         AnimationListener listenser = new AnimationListener()  
101.         {  
102.             @Override  
103.             public void onAnimationEnd(Animation animation)  
104.             {  
105.                 view.clearAnimation();  
106.                 setRotateAni(view, 36, 3996, 110000, Animation.RESTART, Animation.INFINITE, true);  
107.             }  
108.               
109.             @Override  
110.             public void onAnimationRepeat(Animation animation)  
111.             {}  
112.               
113.             @Override  
114.             public void onAnimationStart(Animation animation)  
115.             {}  
116.         };  
117.           
118.         AnimationSet set = new AnimationSet(true);  
119.           
120.           
121.         AlphaAnimation alphaAni = new AlphaAnimation(0.0f, 1f);  
122.         alphaAni.setDuration(1000);  
123.         set.addAnimation(alphaAni);  
124.           
125.          
126.         RotateAnimation rotateAni = new RotateAnimation(0, 36, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);  
127.         rotateAni.setDuration(1000);  
128.         set.addAnimation(rotateAni);  
129.           
130.        
131.         ScaleAnimation scaleAni = new ScaleAnimation(0.0f, 1.0f, 0.0f, 1.0f, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);  
132.         scaleAni.setDuration(1000);  
133.         scaleAni.setAnimationListener(listenser);  
134.         set.addAnimation(scaleAni);  
135.           
136.         view.startAnimation(set);  
137.     }  
138. } 

小代码合集

1：查看是否有存储卡插入
String status=Environment.getExternalStorageState();
if(status.equals(Enviroment.MEDIA_MOUNTED)){
   说明有SD卡插入
}


2：让某个Activity透明
OnCreate 中不设Layout
this.setTheme(R.style.Theme_Transparent);
以下是 Theme_Transparent的定义（注意transparent_bg是一副透明的图片）


3：在屏幕元素中设置句柄
使用Activity.findViewById来取得屏幕上的元素的句柄. 使用该句柄您可以设置或获取任何该对象外露的值.
TextView msgTextView = (TextView)findViewById(R.id.msg);
   msgTextView.setText(R.string.push_me);


4:发送短信


            String body=”this is mms demo”;


           Intent mmsintent = new Intent(Intent.ACTION_SENDTO, Uri.fromParts(”smsto”, number, null));
           mmsintent.putExtra(Messaging.KEY_ACTION_SENDTO_MESSAGE_BODY, body);
           mmsintent.putExtra(Messaging.KEY_ACTION_SENDTO_COMPOSE_MODE, true);
           mmsintent.putExtra(Messaging.KEY_ACTION_SENDTO_EXIT_ON_SENT, true);
            startActivity(mmsintent);


   5:发送彩信


           StringBuilder sb = new StringBuilder();


            sb.append(”file://”);


            sb.append(fd.getAbsoluteFile());


            Intent intent = new Intent(Intent.ACTION_SENDTO, Uri.fromParts(”mmsto”, number, null));
            // Below extra datas are all optional.
            intent.putExtra(Messaging.KEY_ACTION_SENDTO_MESSAGE_SUBJECT, subject);
            intent.putExtra(Messaging.KEY_ACTION_SENDTO_MESSAGE_BODY, body);
            intent.putExtra(Messaging.KEY_ACTION_SENDTO_CONTENT_URI, sb.toString());
            intent.putExtra(Messaging.KEY_ACTION_SENDTO_COMPOSE_MODE, composeMode);
            intent.putExtra(Messaging.KEY_ACTION_SENDTO_EXIT_ON_SENT, exitOnSent);


            startActivity(intent);


7：发送Mail


             mime = “img/jpg”;
            shareIntent.setDataAndType(Uri.fromFile(fd), mime);
            shareIntent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(fd));
            shareIntent.putExtra(Intent.EXTRA_SUBJECT, subject);


            shareIntent.putExtra(Intent.EXTRA_TEXT, body);


8:注册一个 BroadcastReceiver


registerReceiver(mMasterResetReciever, new IntentFilter(”oms.action.MASTERRESET”));


private BroadcastReceiver mMasterResetReciever = new BroadcastReceiver() {


        public void onReceive(Context context, Intent intent){
            String action = intent.getAction();
            if(”oms.action.MASTERRESET”.equals(action)){
                RecoverDefaultConfig();
            }
        }


    };


9:定义ContentObserver，监听某个数据表


private ContentObserver mDownloadsObserver = new DownloadsChangeObserver(Downloads.CONTENT_URI);


private class DownloadsChangeObserver extends ContentObserver {
        public DownloadsChangeObserver(Uri uri) {
            super(new Handler());


        }


        @Override
        public void onChange(boolean selfChange) {｝
        }




10:获得 手机UA


public String getUserAgent(){
    String user_agent = ProductProperties.get(ProductProperties.USER_AGENT_KEY, null);
            return user_agent;
    }


11：清空手机上Cookie


CookieSyncManager.createInstance(getApplicationContext());
        CookieManager.getInstance().removeAllCookie();


12：建立GPRS 连接


   //Dial the GPRS link.
    private boolean openDataConnection() {
        // Set up data connection.
        DataConnection conn = DataConnection.getInstance();


            if (connectMode == 0) {
                ret = conn.openConnection(mContext, “cmwap”, “cmwap”, “cmwap”);
            } else {
                ret = conn.openConnection(mContext, “cmnet”, “”, “”);
            }


    }


13：PreferenceActivity 用法


public class Setting extends PreferenceActivity｛
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.settings)；
    }


｝


Setting.xml:


            android:key=”seting2″
            android:title=”@string/seting2″
            android:summary=”@string/seting2″/>


            android:key=”seting1″
            android:title=”@string/seting1″
            android:summaryOff=”@string/seting1summaryOff”
            android:summaryOn=”@stringseting1summaryOff”/>


14:通过 HttpClient从指定server获取数据


             DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpGet method = new HttpGet(“http://www.baidu.com/1.html”);
            HttpResponse resp;
            Reader reader = null;
            try {
                // AllClientPNames.TIMEOUT
                HttpParams params = new BasicHttpParams();
                params.setIntParameter(AllClientPNames.CONNECTION_TIMEOUT, 10000);
                httpClient.setParams(params);
                resp = httpClient.execute(method);
                int status = resp.getStatusLine().getStatusCode();


                if (status != HttpStatus.SC_OK) return false;


                // HttpStatus.SC_OK;
                return true;
            } catch (ClientProtocolException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } finally {
                if (reader != null) try {
                    reader.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }


15:显示toast
Toast.makeText(this._getApplicationContext(), R.string._item, Toast.LENGTH_SHORT).show();


16:在当前Activity中启动另外一个Activity
startActivity(new Intent(this,目标Activity.class));


17:从当前ContentView从查找控件
(Button)findViewById(R.id.btnAbout)
 R.id.btnAbout指控件id。


18:获取屏幕宽高
DisplayMetrics dm = new DisplayMetrics();
//获取窗口属性
 getWindowManager().getDefaultDisplay().getMetrics(dm);
 int screenWidth = dm.widthPixels;//320
 int screenHeight = dm.heightPixels;//480


19:无标题栏、全屏
//无标题栏
requestWindowFeature(Window.FEATURE_NO_TITLE);
//全屏模式
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
  WindowManager.LayoutParams.FLAG_FULLSCREEN);
注意在setContentView()之前调用，否则无效。


20注册activity
所有用到的Activity都必须在AndroidManifest.xml中注册，否则会报空指针错误。
如：，注意是包名+类名。