本文實例總結了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.程序控制屏幕變亮：
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. 對于特定的程序 發起一個關聯供打開
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);
對于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.設置文本外觀
setTextAppearance(context, android .R.style.TextAppearance_Medium);android :textAppearance="?android :attr/textAppearanceMedium"
8.設置單獨的發起模式：
<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.創建一個圓角圖片
這個的主要原理其實就是利用遮罩，先創建一個圓角方框 然后將圖片放在下面：
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));//然后呢實現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.背景漸變：
首先建立文件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>
在該文件中設置漸變的開始顏色(startColor)、結束顏色(endColor)和角度(angle)
接著創建一個主題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>
然后在AndroidManifest.xml文件中的application或activity中引入該主題,如:
<activity android :name=".ShapeDemo" android :theme="@style/NewTheme">
該方法同樣適用于控件
<?php xml version="1.0" ?>?<response><error>1</error><message>Invalid URL.</message></response>
12. 儲存數據 當你在一個實例中保存靜態數據，此示例關閉后 下一個實例想引用 靜態數據就會為null，這里呢必須重寫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(); }}更多關于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法匯總》、《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控件用法總結》
希望本文所述對大家Android程序設計有所幫助。
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