1. Öffnen Sie die Webseite
Uri uri = Uri.parse("http://www.php.cn");
Intent it = new Intent(Intent.ACTION_VIEW, uri);
startActivity(it);2. Holen Sie sich den Inhalt der Webseite
public String posturl(String url){
InputStream is = null;
String result = "";
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(url);
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
}catch(Exception e){
return "Fail to establish http connection!"+e.toString();
}
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"utf-8"));
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result=sb.toString();
}catch(Exception e){
return "Fail to convert net stream!";
}
return result;
}3. Fügen Sie einen Hyperlink hinzu
textView1.setText(Html.fromHtml("<a href='http://www.php.cn'>php中文网 </a>"));
textView1.setMovementMethod(LinkMovementMethod.getInstance());4. Zugriff auf das Netzwerk zulassen
<uses-permission android:name="android.permission.INTERNET" />
5. Einfache Nachrichtenbox
new AlertDialog.Builder(this)
.setTitle("标题")
.setMessage("简单消息框")
.setPositiveButton("确定", null)
.show();6. Dialogfelder zum Bestätigen und Abbrechen
new AlertDialog.Builder(this)
.setTitle("确认")
.setMessage("确定吗？")
.setPositiveButton("是", null)
.setNegativeButton("否", null)
.show();7. Dialogbox mit Eingabefeld
new AlertDialog.Builder(this)
.setTitle("请输入")
.setIcon(android.R.drawable.ic_dialog_info)
.setView(new EditText(this))
.setPositiveButton("确定", null)
.setNegativeButton("取消", null)
.show();8. Dialogfeld mit Optionsfeldern
new AlertDialog.Builder(this)
.setTitle("请选择")
.setIcon(android.R.drawable.ic_dialog_info)
.setSingleChoiceItems(new String[] {"选项1","选项2","选项3","选项4"}, 0,
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
}
}
)
.setNegativeButton("取消", null)
.show();
9. Dialogfeld mit mehreren Auswahlfeldern
new AlertDialog.Builder(this)
.setTitle("多选框")
.setMultiChoiceItems(new String[] {"选项1","选项2","选项3","选项4"}, null, null)
.setPositiveButton("确定", null)
.setNegativeButton("取消", null)
.show();10. Dialogbox mit Listenfeld
new AlertDialog.Builder(this)
.setTitle("列表框")
.setItems(new String[] {"列表项1","列表项2","列表项3"}, null)
.setNegativeButton("确定", null)
.show();11. Bilderrahmen
ImageView img = new ImageView(this);
img.setImageResource(R.drawable.ic_launcher);
new AlertDialog.Builder(this)
.setTitle("图片框")
.setView(img)
.setPositiveButton("确定", null)
.show();
12. Es erscheint ein kurzes Eingabeaufforderungsfeld
public void alert(String txt){
Toast.makeText(MainActivity.this,txt, 1).show();
}
13. URL-Transkodierung
public String urlencode(String str) throws UnsupportedEncodingException{
return java.net.URLEncoder.encode(str, "utf-8");
}14. URL-Dekodierung
public String urldecode(String str) throws UnsupportedEncodingException{
return java.net.URLDecoder.decode(str, "utf-8");
}
15. Holen Sie sich den Quellcode der Webseite
//得到二进制数据
public String getDatas(String path) throws Exception{
// 类 URL 代表一个统一资源定位符，它是指向互联网“资源”的指针。
URL url = new URL(path);
// 每个 HttpURLConnection 实例都可用于生成单个请求，
//但是其他实例可以透明地共享连接到 HTTP 服务器的基础网络
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
//设置 URL 请求的方法
conn.setRequestMethod("GET");
//设置一个指定的超时值（以毫秒为单位），
//该值将在打开到此 URLConnection 引用的资源的通信链接时使用。
conn.setConnectTimeout(5 * 1000);
// conn.getInputStream()返回从此打开的连接读取的输入流
InputStream inStream = conn.getInputStream();// 通过输入流获取html数据
byte[] data = readInputStream(inStream);// 得到html的二进制数据
String html = new String(data);
return html;
}
//读取输入流中的数据，返回字节数组byte[]
public byte[] readInputStream(InputStream inStream) throws Exception{
//此类实现了一个输出流，其中的数据被写入一个 byte 数组
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
// 字节数组
byte[] buffer = new byte[1024];
int len = 0;
//从输入流中读取一定数量的字节，并将其存储在缓冲区数组buffer 中
while ((len = inStream.read(buffer)) != -1) {
// 将指定 byte 数组中从偏移量 off 开始的 len 个字节写入此输出流
outStream.write(buffer, 0, len);
}
inStream.close();
//toByteArray()创建一个新分配的 byte 数组。
return outStream.toByteArray();
}16. Netzwerkbilder anzeigen
public Bitmap returnBitMap(String url) {
URL myFileUrl = null;
Bitmap bitmap = null;
try {
myFileUrl = new URL(url);
} catch (MalformedURLException e) {
e.printStackTrace();
}
try {
HttpURLConnection conn = (HttpURLConnection) myFileUrl.openConnection();
conn.setDoInput(true);
conn.connect();
InputStream is = conn.getInputStream();
bitmap = BitmapFactory.decodeStream(is);
is.close();
} catch (IOException e) {
e.printStackTrace();
}
return bitmap;
}
ImageView imView = (ImageView) findViewById(R.id.pic1);
imView.setImageBitmap(returnBitMap("https://img.php.cn/upload/course/000/001/120/595af5fa9f34f845.png"));
17. Schaltflächenklick-Ereignis
//登录检测
Button button=(Button)findViewById(R.id.button1);
button.setOnClickListener(new OnClickListener(){
public void onClick(View v){
}
});
//登录检测18. Dialog-Hörveranstaltung
new AlertDialog.Builder(this)
.setTitle("亲,是否退出?")
.setPositiveButton("确定", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface arg0, int arg1) {
// TODO Auto-generated method stub
alert("你点了确定");
}})
.setNegativeButton("取消",new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
alert("你已经取消了");
}})
.show();
public void alert(String txt){
Toast.makeText(this,txt, 1).show();
}19. Vorgehensweise zum Beenden von Android
private void showTips() {
AlertDialog alertDialog = new AlertDialog.Builder(this)
.setTitle("退出程序").setMessage("是否退出程序")
.setPositiveButton("确定", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
finish();
}
}).setNegativeButton("取消",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
return;
}
}).create(); // 创建对话框
alertDialog.show(); // 显示对话框
}
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK && event.getRepeatCount() == 0) {
showTips();
return false;
}
return super.onKeyDown(keyCode, event);
}20. Android WebView-Komponente
WebView mWebView = new WebView(this);
mWebView.setWebViewClient(new webViewClient());//调用自身打开
mWebView.getSettings().setJavaScriptEnabled(true);
mWebView.loadUrl("http://www.php.cn/member/1.html");
setContentView(mWebView);
class webViewClient extends WebViewClient{
//重写shouldOverrideUrlLoading方法，使点击链接后不使用其他的浏览器打开。
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(url);
//如果不需要其他对点击链接事件的处理返回true，否则返回false
return true;
}
}
21. Aktivitätssprung ohne Parameter
Intent it = new Intent(Activity.Main.this, Activity2.class); startActivity(it);
22. Übergeben Sie Daten an die nächste Aktivität (mithilfe von Bundle und Intent.putExtras)
Intent it = new Intent(Activity.Main.this, Activity2.class);
Bundle bundle=new Bundle();
bundle.putString("name", "This is from MainActivity!");
it.putExtras(bundle); // it.putExtra(“test”, "shuju”);
startActivity(it); // startActivityForResult(it,REQUEST_CODE); Für die Datenerfassung können Sie Folgendes verwenden:
Bundle bundle=getIntent().getExtras();
String name=bundle.getString("name");23. Geben Sie das Ergebnis an die vorherige Aktivität zurück (mit setResult für die Aktivität, die von startActivityForResult(it, REQUEST_CODE) gestartet wurde)
Intent intent=getIntent();
Bundle bundle2=new Bundle();
bundle2.putString("name", "This is from ShowMsg!");
intent.putExtras(bundle2);
setResult(RESULT_OK, intent);24. Rufen Sie die Ergebnisverarbeitungsfunktion der vorherigen Aktivität (onActivityResult) zurück
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
super.onActivityResult(requestCode, resultCode, data);
if (requestCode==REQUEST_CODE){
if(resultCode==RESULT_CANCELED)
setTitle("cancle");
else if (resultCode==RESULT_OK) {
String temp=null;
Bundle bundle=data.getExtras();
if(bundle!=null) temp=bundle.getString("name");
setTitle(temp);
}
}
}25. AndroidTimer
Timer timer = new Timer();
timer.schedule(task,10000,2000);
TimerTask task = new TimerTask(){
public void run() {
Message message = new Message();
message.what = 1;
handler.sendMessage(message);
}
};
Handler handler = new Handler(){
public void handleMessage(Message msg) {
switch (msg.what) {
case 1:
alert("hear me?");
break;
}
super.handleMessage(msg);
}
};26. Hintergrundmusik für Android einfügen
MediaPlayer mediaPlayer = new MediaPlayer();
Uri uri = Uri
.parse("http://www.php.cn/asset/1.mp3");
try {
mediaPlayer.setDataSource(Sound.this, uri);
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SecurityException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
mediaPlayer.prepare();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
mediaPlayer.start();27. Konvertierung zwischen int und string
1 Wie konvertiert man String in Integer?
A. Es gibt zwei Methoden:
1). parseInt([String]); oder
i = Integer.parseInt([String],[int radix]);
2). :
1.) String s = String.valueOf(i);
2.) String s = Integer.toString(i);
3.) String s = "" + i;
Hinweis: Die Methoden zum Konvertieren von Double, Float und Long in Strings sind ähnlich.
28. Ermitteln Sie die Bildschirmbreite und -höhe
29. Bildziehen
DisplayMetrics dm = getResources().getDisplayMetrics(); int screenWidth = dm.widthPixels; int screenHeight = dm.heightPixels - 50;
private int screenWidth;
private int screenHeight;
private ImageView img1;
private ImageView img2;
img1 = (ImageView) findViewById(R.id.imageView1);
img2 = (ImageView) findViewById(R.id.imageView2);
DisplayMetrics dm = getResources().getDisplayMetrics();
screenWidth = dm.widthPixels;
screenHeight = dm.heightPixels - 50;
img1.setOnTouchListener(movingEventListener);
img2.setOnTouchListener(movingEventListener);
private OnTouchListener movingEventListener = new OnTouchListener() {
int lastX, lastY;
@Override
public boolean onTouch(View v, MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
lastX = (int) event.getRawX();
lastY = (int) event.getRawY();
break;
case MotionEvent.ACTION_MOVE:
int dx = (int) event.getRawX() - lastX;
int dy = (int) event.getRawY() - lastY;
int left = v.getLeft() + dx;
int top = v.getTop() + dy;
int right = v.getRight() + dx;
int bottom = v.getBottom() + dy;
// 设置不能出界
if (left < 0) {
left = 0;
right = left + v.getWidth();
}
if (right > screenWidth) {
right = screenWidth;
left = right - v.getWidth();
}
if (top < 0) {
top = 0;
bottom = top + v.getHeight();
}
if (bottom > screenHeight) {
bottom = screenHeight;
top = bottom - v.getHeight();
}
v.layout(left, top, right, bottom);
lastX = (int) event.getRawX();
lastY = (int) event.getRawY();
break;
case MotionEvent.ACTION_UP:
break;
}
return true;
}
}; private void addNotificaction(int id) {
NotificationManager manager = (NotificationManager) this
.getSystemService(Context.NOTIFICATION_SERVICE);
// 创建一个Notification
Notification notification = new Notification();
// 设置显示在手机最上边的状态栏的图标
notification.icon = R.drawable.ic_launcher;
// 当当前的notification被放到状态栏上的时候，提示内容
notification.tickerText = "注意了，我被扔到状态栏了";
// 添加声音提示
notification.defaults=Notification.DEFAULT_SOUND;
// audioStreamType的值必须AudioManager中的值，代表着响铃的模式
notification.audioStreamType= android.media.AudioManager.ADJUST_LOWER;
//下边的两个方式可以添加音乐
//notification.sound = Uri.parse("http://www.php.cn/asset/1.mp3");
//notification.sound = Uri.withAppendedPath(Audio.Media.INTERNAL_CONTENT_URI, "6");
Intent intent = new Intent(this, functions.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_ONE_SHOT);
// 点击状态栏的图标出现的提示信息设置
notification.setLatestEventInfo(this, "内容提示：", "我就是一个测试文件", pendingIntent);
manager.notify(id, notification);
}private void showPopUp(View v) {
LinearLayout layout = new LinearLayout(this);
layout.setBackgroundColor(Color.GRAY);
TextView tv = new TextView(this);
tv.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
tv.setText("I'm a pop -----------------------------!");
tv.setTextColor(Color.WHITE);
layout.addView(tv);
PopupWindow popupWindow = new PopupWindow(layout,120,120);
popupWindow.setFocusable(true);
popupWindow.setOutsideTouchable(true);
popupWindow.setBackgroundDrawable(new BitmapDrawable());
int[] location = new int[2];
v.getLocationOnScreen(location);
popupWindow.showAtLocation(v, Gravity.NO_GRAVITY, location[0], location[1]-popupWindow.getHeight());
}
showPopUp(LayoutInflater.from(getBaseContext()).inflate(R.layout.popview, null));LayoutInflater.from(getBaseContext()).inflate(R.layout.popview, null);
<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
Bitte nicht erneut drucken~~~
权限 <uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
WindowManager wm=(WindowManager)getApplicationContext().getSystemService("window");
WindowManager.LayoutParams wmParams = new WindowManager.LayoutParams();
wmParams.type=2002; //type是关键，这里的2002表示系统级窗口，你也可以试试2003。
wmParams.format=1;
wmParams.flags=40;
wmParams.width=40;
wmParams.height=40;
wm.addView(LayoutInflater.from(getBaseContext()).inflate(R.layout.popview, null), wmParams);//创建ViewDas obige ist der detaillierte Inhalt vonAndroid-Grundlagen: Schwebende Schaltflächen und Benachrichtigungen in der Statusleiste. Für weitere Informationen folgen Sie bitte anderen verwandten Artikeln auf der PHP chinesischen Website!
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