編輯:關於Android編程
司馬光砸缸,多開幾個小水管,搶救小朋友。
import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.InputStream; import java.io.InputStreamReader; import java.io.RandomAccessFile; import java.net.HttpURLConnection; import java.net.URL; public class MutileThreadDownload { /** * 線程的數量 */ private static int threadCount = 3; /** * 每個下載區塊的大小 */ private static long blocksize; /** * 正在運行的線程的數量 */ private static int runningThreadCount; /** * @param args * @throws Exception */ public static void main(String[] args) throws Exception { // 服務器文件的路徑 String path = "http://192.168.1.100:8080/ff.exe"; URL url = new URL(path); HttpURLConnection conn = (HttpURLConnection) url.openConnection(); conn.setRequestMethod("GET"); conn.setConnectTimeout(5000); int code = conn.getResponseCode(); if (code == 200) { long size = conn.getContentLength();// 得到服務端返回的文件的大小 System.out.println("服務器文件的大小:" + size); blocksize = size / threadCount; // 1.首先在本地創建一個大小跟服務器一模一樣的空白文件。 File file = new File("temp.exe"); RandomAccessFile raf = new RandomAccessFile(file, "rw"); raf.setLength(size); // 2.開啟若干個子線程分別去下載對應的資源。 runningThreadCount = threadCount; for (int i = 1; i <= threadCount; i++) { long startIndex = (i - 1) * blocksize; long endIndex = i * blocksize - 1; if (i == threadCount) { // 最後一個線程 endIndex = size - 1; } System.out.println("開啟線程:" + i + "下載的位置:" + startIndex + "~" + endIndex); new DownloadThread(path, i, startIndex, endIndex).start(); } } conn.disconnect(); } private static class DownloadThread extends Thread { private int threadId; private long startIndex; private long endIndex; private String path; public DownloadThread(String path, int threadId, long startIndex, long endIndex) { this.path = path; this.threadId = threadId; this.startIndex = startIndex; this.endIndex = endIndex; } @Override public void run() { try { // 當前線程下載的總大小 int total = 0; File positionFile = new File(threadId + ".txt"); URL url = new URL(path); HttpURLConnection conn = (HttpURLConnection) url .openConnection(); conn.setRequestMethod("GET"); // 接著從上一次的位置繼續下載數據 if (positionFile.exists() && positionFile.length() > 0) {// 判斷是否有記錄 FileInputStream fis = new FileInputStream(positionFile); BufferedReader br = new BufferedReader( new InputStreamReader(fis)); // 獲取當前線程上次下載的總大小是多少 String lasttotalstr = br.readLine(); int lastTotal = Integer.valueOf(lasttotalstr); System.out.println("上次線程" + threadId + "下載的總大小:" + lastTotal); startIndex += lastTotal; total += lastTotal;// 加上上次下載的總大小。 fis.close(); } conn.setRequestProperty("Range", "bytes=" + startIndex + "-" + endIndex); conn.setConnectTimeout(5000); int code = conn.getResponseCode(); System.out.println("code=" + code); InputStream is = conn.getInputStream(); File file = new File("temp.exe"); RandomAccessFile raf = new RandomAccessFile(file, "rw"); // 指定文件開始寫的位置。 raf.seek(startIndex); System.out.println("第" + threadId + "個線程:寫文件的開始位置:" + String.valueOf(startIndex)); int len = 0; byte[] buffer = new byte[512]; while ((len = is.read(buffer)) != -1) { RandomAccessFile rf = new RandomAccessFile(positionFile, "rwd"); raf.write(buffer, 0, len); total += len; rf.write(String.valueOf(total).getBytes()); rf.close(); } is.close(); raf.close(); } catch (Exception e) { e.printStackTrace(); } finally { // 只有所有的線程都下載完畢後 才可以刪除記錄文件。 synchronized (MutileThreadDownload.class) { System.out.println("線程" + threadId + "下載完畢了"); runningThreadCount--; if (runningThreadCount < 1) { System.out.println("所有的線程都工作完畢了。刪除臨時記錄的文件"); for (int i = 1; i <= threadCount; i++) { File f = new File(i + ".txt"); System.out.println(f.delete()); } } } } } } }
同上
pb.xml
package com.itheima.mutilethread; import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.InputStream; import java.io.InputStreamReader; import java.io.RandomAccessFile; import java.net.HttpURLConnection; import java.net.URL; import java.util.ArrayList; import java.util.List; import android.app.Activity; import android.os.Bundle; import android.os.Environment; import android.os.Handler; import android.os.Message; import android.text.TextUtils; import android.view.View; import android.widget.EditText; import android.widget.LinearLayout; import android.widget.ProgressBar; import android.widget.Toast; public class MainActivity extends Activity { protected static final int DOWNLOAD_ERROR = 1; private static final int THREAD_ERROR = 2; public static final int DWONLOAD_FINISH = 3; private EditText et_path; private EditText et_count; /** * 存放進度條的布局 */ private LinearLayout ll_container; /** * 進度條的集合 */ private Listpbs; /** * android下的消息處理器,在主線程創建,才可以更新ui */ private Handler handler = new Handler(){ public void handleMessage(Message msg) { switch (msg.what) { case DOWNLOAD_ERROR: Toast.makeText(getApplicationContext(), "下載失敗", 0).show(); break; case THREAD_ERROR: Toast.makeText(getApplicationContext(), "下載失敗,請重試", 0).show(); break; case DWONLOAD_FINISH: Toast.makeText(getApplicationContext(), "下載完成", 0).show(); break; } }; }; /** * 線程的數量 */ private int threadCount = 3; /** * 每個下載區塊的大小 */ private long blocksize; /** * 正在運行的線程的數量 */ private int runningThreadCount; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); et_path = (EditText) findViewById(R.id.et_path); et_count = (EditText) findViewById(R.id.et_count); ll_container = (LinearLayout) findViewById(R.id.ll_container); } /** * 下載按鈕的點擊事件 * @param view */ public void downLoad(View view){ //下載文件的路徑 final String path = et_path.getText().toString().trim(); if(TextUtils.isEmpty(path)){ Toast.makeText(this, "對不起下載路徑不能為空", 0).show(); return; } String count = et_count.getText().toString().trim(); if(TextUtils.isEmpty(path)){ Toast.makeText(this, "對不起,線程數量不能為空", 0).show(); return; } threadCount = Integer.parseInt(count); //清空掉舊的進度條 ll_container.removeAllViews(); //在界面裡面添加count個進度條 pbs = new ArrayList (); for(int j=0;j 0) {// 判斷是否有記錄 FileInputStream fis = new FileInputStream(positionFile); BufferedReader br = new BufferedReader( new InputStreamReader(fis)); // 獲取當前線程上次下載的總大小是多少 String lasttotalstr = br.readLine(); int lastTotal = Integer.valueOf(lasttotalstr); System.out.println("上次線程" + threadId + "下載的總大小:" + lastTotal); startIndex += lastTotal; total += lastTotal;// 加上上次下載的總大小。 fis.close(); //存數據庫。 //_id path threadid total } conn.setRequestProperty("Range", "bytes=" + startIndex + "-" + endIndex); conn.setConnectTimeout(5000); int code = conn.getResponseCode(); System.out.println("code=" + code); InputStream is = conn.getInputStream(); File file = new File(Environment.getExternalStorageDirectory(),getFileName(path)); RandomAccessFile raf = new RandomAccessFile(file, "rw"); // 指定文件開始寫的位置。 raf.seek(startIndex); System.out.println("第" + threadId + "個線程:寫文件的開始位置:" + String.valueOf(startIndex)); int len = 0; byte[] buffer = new byte[1024]; while ((len = is.read(buffer)) != -1) { RandomAccessFile rf = new RandomAccessFile(positionFile, "rwd"); raf.write(buffer, 0, len); total += len; rf.write(String.valueOf(total).getBytes()); rf.close(); pbs.get(threadId-1).setProgress(total); } is.close(); raf.close(); } catch (Exception e) { e.printStackTrace(); Message msg = Message.obtain(); msg.what = THREAD_ERROR; handler.sendMessage(msg); } finally { // 只有所有的線程都下載完畢後 才可以刪除記錄文件。 synchronized (MainActivity.class) { System.out.println("線程" + threadId + "下載完畢了"); runningThreadCount--; if (runningThreadCount < 1) { System.out.println("所有的線程都工作完畢了。刪除臨時記錄的文件"); for (int i = 1; i <= threadCount; i++) { File f = new File(Environment.getExternalStorageDirectory(),getFileName(path)+ i + ".txt"); System.out.println(f.delete()); } Message msg = Message.obtain(); msg.what = DWONLOAD_FINISH; handler.sendMessage(msg); } } } } } //http://192.168.1.100:8080/aa.exe private String getFileName(String path){ int start = path.lastIndexOf("/")+1; return path.substring(start); } }
xUtils-master.zip
xUtils-2.4.7.jar
package com.itheima.download2; import java.io.File; import android.app.Activity; import android.os.Bundle; import android.text.TextUtils; import android.view.View; import android.widget.EditText; import android.widget.TextView; import android.widget.Toast; import com.lidroid.xutils.HttpUtils; import com.lidroid.xutils.exception.HttpException; import com.lidroid.xutils.http.HttpHandler; import com.lidroid.xutils.http.ResponseInfo; import com.lidroid.xutils.http.callback.RequestCallBack; public class MainActivity extends Activity { private EditText et_path; private TextView tv_info; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); et_path = (EditText) findViewById(R.id.et_path); tv_info = (TextView) findViewById(R.id.tv_info); } public void download(View view) { String path = et_path.getText().toString().trim(); if (TextUtils.isEmpty(path)) { Toast.makeText(this, "請輸入下載的路徑", 0).show(); return; } else { HttpUtils http = new HttpUtils(); HttpHandler handler = http.download(path, "/sdcard/abc.mp3", true, // 如果目標文件存在,接著未完成的部分繼續下載。服務器不支持RANGE時將從新下載。 true, // 如果從請求返回信息中獲取到文件名,下載完成後自動重命名。 new RequestCallBack() { @Override public void onStart() { tv_info.setText("conn..."); } @Override public void onLoading(long total, long current, boolean isUploading) { tv_info.setText(current + "/" + total); } @Override public void onSuccess(ResponseInfo responseInfo) { tv_info.setText("downloaded:" + responseInfo.result.getPath()); } @Override public void onFailure(HttpException error, String msg) { tv_info.setText(msg); } }); } } }
人品計算器的案例
package com.itheima.intent2; import android.app.Activity; import android.content.Intent; import android.net.Uri; import android.os.Bundle; import android.view.View; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } public void click(View view) { // 打 action // 人 數據 // 附件的數據 Category 類別 Intent intent = new Intent(); intent.setAction("com.itheima.intent2.open2"); intent.addCategory(Intent.CATEGORY_DEFAULT); // URL:統一資源定位符 http https ftp rtsp: URI:統一資源標識符 url是uri的一個子集 // intent.setData(Uri.parse("jianren:張三")); // intent.setType("application/person"); intent.setDataAndType(Uri.parse("jianren:張三"), "application/person"); startActivity(intent); } }
package com.itheima.intent2; import android.app.Activity; import android.os.Bundle; public class SecondActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_second); } }
打開浏覽器
package com.itheima.openbrowser; import android.app.Activity; import android.content.Intent; import android.net.Uri; import android.os.Bundle; import android.view.View; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } public void click(View view){ // //// // // // // Intent intent = new Intent(); intent.setAction("android.intent.action.VIEW"); intent.addCategory("android.intent.category.DEFAULT"); intent.addCategory("android.intent.category.BROWSABLE"); intent.setData(Uri.parse("http://www.baidu.com")); startActivity(intent); } }
package com.itheima.rpcalc; import java.util.Random; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.widget.TextView; public class CalcActivity extends Activity { private TextView tv_result; //當activity被創建的時候調用的方法 @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_calc); tv_result = (TextView) findViewById(R.id.tv_result); Intent intent = getIntent(); String name = intent.getStringExtra("name"); byte[] result = name.getBytes(); int number = 0; for(byte b :result){ number += b&0xff; } int sorce = Math.abs(number)%100; tv_result.setText(name+"的人品:"+sorce); } }
package com.itheima.rpcalc; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.text.TextUtils; import android.view.View; import android.widget.EditText; import android.widget.Toast; public class MainActivity extends Activity { private EditText et_name; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); et_name = (EditText) findViewById(R.id.et_name); } //顯式意圖 :必須指定要激活的組件的完整包名和類名 (應用程序之間耦合在一起) // 一般激活自己應用的組件的時候 采用顯示意圖 //隱式意圖: 只需要指定要動作和數據就可以 ( 好處應用程序之間沒有耦合) //激活別人寫的應用 隱式意圖, 不需要關心對方的包名和類名 public void enter(View view){ String name = et_name.getText().toString().trim(); if(TextUtils.isEmpty(name)){ Toast.makeText(this, "請輸入姓名", 0).show(); return; } //意圖 開電視 打人 打醬油 Intent intent = new Intent(this, CalcActivity.class); intent.putExtra("name", name); //顯式意圖 //intent.setClassName(getPackageName(), "com.itheima.rpcalc.CalcActivity");//不指定動作,也不指定數據 直接指定要激活的組件 startActivity(intent); //隱式意圖 //intent.setAction(action); //intent.setData(data); } }
sms_item.xml
activity_sms.xml
activity_main.xml
package com.itheima.smshelper; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.widget.AdapterView; import android.widget.AdapterView.OnItemClickListener; import android.widget.ArrayAdapter; import android.widget.ListView; public class ListNumberActivity extends Activity { private ListView lv; private String[] objects = { "1234","34324","5643543","32424" }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_sms); lv = (ListView) findViewById(R.id.lv); lv.setAdapter(new ArrayAdapter(this, R.layout.sms_item, R.id.tv_info, objects)); lv.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView parent, View view, int position, long id) { String smsinfo = objects[position]; Intent data = new Intent(); data.putExtra("smsinfo", smsinfo); //設置數據。 setResult(1, data); //關閉掉當前的activity,並且回傳數據 onActivityResult(). finish(); } }); } }
package com.itheima.smshelper; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.widget.AdapterView; import android.widget.AdapterView.OnItemClickListener; import android.widget.ArrayAdapter; import android.widget.ListView; public class ListSmsActivity extends Activity { private ListView lv; private String[] objects = { "玫瑰香香,情人黏黏,情話甜甜,情歌綿綿;花燈燦燦,禮花點點,好運連連,好夢圓圓。情人節喜逢元宵節,喜鵲登枝蝴蝶成雙鴛鴦成對雙喜臨門祝雙節快樂,合家團團圓圓,甜甜蜜蜜,開開心心,幸幸福福", "情人節快到了,我精心挑選玫瑰花、百合花和滿天星,扎成一束鮮花隨短信送給你,火紅的玫瑰代表熱烈奔放,潔白的百合代表百年好合,小小的滿天星代表幸福美好。願你的情人節熱烈奔放,你們的愛情百年好合,你們的生活幸福美滿。預祝情人節快樂", "^o^滿天星光,最愛你許過願望的那一顆,鮮花綻放,最愛你摘下微笑的那一朵,曼妙旋律,最愛你感動落淚的那一段,親愛的,情人節快樂,愛你。 ", "^o^寶貝,情人節到了,送你一束玫瑰,用真心塑料紙包扎,系上快樂彩帶,噴點愛的香水,插一張真情卡片,寫著:寶貝,願我的愛能帶給你一生的快樂!" }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_sms); lv = (ListView) findViewById(R.id.lv); lv.setAdapter(new ArrayAdapter(this, R.layout.sms_item, R.id.tv_info, objects)); lv.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView parent, View view, int position, long id) { String smsinfo = objects[position]; Intent data = new Intent(); data.putExtra("smsinfo", smsinfo); //設置數據。 setResult(0, data); //關閉掉當前的activity,並且回傳數據 onActivityResult(). finish(); } }); } }
package com.itheima.smshelper; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.telephony.SmsManager; import android.view.View; import android.widget.EditText; import android.widget.Toast; public class MainActivity extends Activity { private EditText et_content; private EditText et_number; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); et_content = (EditText) findViewById(R.id.et_content); et_number = (EditText) findViewById(R.id.et_number); } public void selectSms(View view) { Intent intent = new Intent(this, ListSmsActivity.class); // 開啟一個新的界面,並且獲取界面的返回值 // startActivity(intent); // int requestCode 請求碼 startActivityForResult(intent, 0); } public void selectNumber(View view) { Intent intent = new Intent(this, ListNumberActivity.class); // 開啟一個新的界面,並且獲取界面的返回值 // startActivity(intent); // int requestCode 請求碼 startActivityForResult(intent, 1); } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { if (data != null) { String smsinfo = data.getStringExtra("smsinfo"); if (resultCode == 0) { et_content.setText(smsinfo); } else if (resultCode == 1) { et_number.setText(smsinfo); } } super.onActivityResult(requestCode, resultCode, data); } public void sendSms(View view){ String content = et_content.getText().toString().trim(); String number = et_number.getText().toString().trim(); SmsManager.getDefault().sendTextMessage(number, null, content, null, null); Toast.makeText(this, "發送成功", 0).show(); } }
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