Android實用編程技巧代碼總結_Android

本文執行個體總結了Android實用編程技巧。分享給大家供大家參考，具體如下：

1.讓一個圖片透明：

Bitmap buffer = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_4444);buffer.eraseColor(Color.TRANSPARENT);

2.直接發送郵件：

Intent intent = new Intent(Intent.ACTION_SENDTO, Uri .fromParts("mailto", "test@test.com", null));intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);context.startActivity(intent);

3.程式控制螢幕變亮：

WindowManager.LayoutParams lp = getWindow().getAttributes();lp.screenBrightness = 100 / 100.0f;getWindow().setAttributes(lp);

4.過濾特定文本

Filter filter = myAdapter.getFilter();filter.filter(mySearchText);

5.scrollView scroll停止事件

setOnScrollListener(new OnScrollListener(){public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {// TODO Auto-generated method stub  }public void onScrollStateChanged(AbsListView view, int scrollState) {// TODO Auto-generated method stubif(scrollState == 0) Log.i("a", "scrolling stopped...");  } });}

6. 對於特定的程式 發起一個關聯供開啟

Bitmap bmp = getImageBitmap(jpg);String path = getFilesDir().getAbsolutePath() + "/test.png";File file = new File(path);FileOutputStream fos = new FileOutputStream(file);bmp.compress( CompressFormat.PNG, 100, fos ); fos.close();  Intent intent = new Intent();  intent.setAction(android .content.Intent.ACTION_VIEW);  intent.setDataAndType(Uri .fromFile(new File(path)), "image/png");  startActivity(intent);

對於圖片上邊的不適用索引格式會出錯。

Intent intent = new Intent();intent.setAction(android .content.Intent.ACTION_VIEW);File file = new File("/sdcard/test.mp4");intent.setDataAndType(Uri .fromFile(file), "video/*");startActivity(intent);Intent intent = new Intent();intent.setAction(android .content.Intent.ACTION_VIEW);File file = new File("/sdcard/test.mp3");intent.setDataAndType(Uri .fromFile(file), "audio/*");startActivity(intent);

7.設定文本外觀

setTextAppearance(context, android .R.style.TextAppearance_Medium);android :textAppearance="?android :attr/textAppearanceMedium"

8.設定單獨的發起模式：

<activity android :name=".ArtistActivity" android :label="Artist" android :launchMode="singleTop"></activity>

Intent i = new Intent();i.putExtra(EXTRA_KEY_ARTIST, id);i.setClass(this, ArtistActivity.class);i.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);startActivity(i);

9.建立一個圓角圖片

這個的主要原理其實就是利用遮罩，先建立一個圓角方框 然後將圖片放在下面：

Bitmap myCoolBitmap = ... ;   int w = myCoolBitmap.getWidth(), h = myCoolBitmap.getHeight();   Bitmap rounder = Bitmap.createBitmap(w,h,Bitmap.Config.ARGB_8888);   Canvas canvas = new Canvas(rounder);   Paint xferPaint = new Paint(Paint.ANTI_ALIAS_FLAG);   xferPaint.setColor(Color.RED);   canvas.drawRoundRect(new RectF(0,0,w,h), 20.0f, 20.0f, xferPaint);   xferPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));//然後呢實現canvas.drawBitmap(myCoolBitmap, 0,0, null);canvas.drawBitmap(rounder, 0, 0, xferPaint);

10.在notification 上的icon上加上數字 給人提示有多少個未讀

Notification notification = new Notification (icon, tickerText, when);notification .number = 4;

11.背景漸層：

首先建立檔案drawable/shape.xml

<?xml version="1.0" encoding="utf-8"?><shape xmlns:android ="http://schemas.android .com/apk/res/android " android :shape="rectangle">  <gradient android :startColor="#FFFFFFFF" android :endColor="#FFFF0000"      android :angle="270"/></shape>

在該檔案中設定漸層的開始顏色(startColor)、結束顏色(endColor)和角度(angle)

接著建立一個主題values/style.xml

<?xml version="1.0" encoding="utf-8"?><resources><style name="NewTheme" parent="android :Theme"><item name="android :background">@drawable/shape</item></style></resources>

然後在AndroidManifest.xml檔案中的application或activity中引入該主題,如:

<activity android :name=".ShapeDemo" android :theme="@style/NewTheme">

該方法同樣適用於控制項

<?php xml version="1.0" ?>?<response><error>1</error><message>Invalid URL.</message></response>

12. 儲存資料 當你在一個執行個體中儲存待用資料，此樣本關閉後 下一個執行個體想引用 待用資料就會為null，這裡呢必須重寫applition

public class MyApplication extends Application{  private String thing = null;  public String getThing(){   return thing;  }  public void setThing( String thing ){   this.thing = thing;  }}public class MyActivity extends Activity {   private MyApplication app;   public void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     app = ((MyApplication)getApplication());     String thing = app.getThing();   }}

更多關於Android相關內容感興趣的讀者可查看本站專題：《Android開發入門與進階教程》、《Android視圖View技巧總結》、《Android布局layout技巧總結》、《Android調試技巧與常見問題解決方案匯總》、《Android多媒體操作技巧匯總(音頻,視頻,錄音等)》、《Android基本組件用法總結》及《Android控制項用法總結》

希望本文所述對大家Android程式設計有所協助。