編輯：關於Android編程
打開大家手上的項目，基本都會有一大批的輔助類，今天特此整理出10個基本每個項目中都會使用的工具類，用於快速開發~~
在此感謝群裡給我發項目中工具類的兄弟/姐妹~
package com.zhy.utils;
import android.util.Log;
/**
* Log統一管理類
*
*
*
*/
public class L
{
private L()
{
/* cannot be instantiated */
throw new UnsupportedOperationException(cannot be instantiated);
}
public static boolean isDebug = true;// 是否需要打印bug，可以在application的onCreate函數裡面初始化
private static final String TAG = way;
// 下面四個是默認tag的函數
public static void i(String msg)
{
if (isDebug)
Log.i(TAG, msg);
}
public static void d(String msg)
{
if (isDebug)
Log.d(TAG, msg);
}
public static void e(String msg)
{
if (isDebug)
Log.e(TAG, msg);
}
public static void v(String msg)
{
if (isDebug)
Log.v(TAG, msg);
}
// 下面是傳入自定義tag的函數
public static void i(String tag, String msg)
{
if (isDebug)
Log.i(tag, msg);
}
public static void d(String tag, String msg)
{
if (isDebug)
Log.i(tag, msg);
}
public static void e(String tag, String msg)
{
if (isDebug)
Log.i(tag, msg);
}
public static void v(String tag, String msg)
{
if (isDebug)
Log.i(tag, msg);
}
}
網上看到的類，注釋上應該原創作者的名字，很簡單的一個類；網上也有很多提供把日志記錄到SDCard上的，不過我是從來沒記錄過，所以引入個最簡單的，大家可以進行評價是否需要擴充~~
package com.zhy.utils;
import android.content.Context;
import android.widget.Toast;
/**
* Toast統一管理類
*
*/
public class T
{
private T()
{
/* cannot be instantiated */
throw new UnsupportedOperationException(cannot be instantiated);
}
public static boolean isShow = true;
/**
* 短時間顯示Toast
*
* @param context
* @param message
*/
public static void showShort(Context context, CharSequence message)
{
if (isShow)
Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
}
/**
* 短時間顯示Toast
*
* @param context
* @param message
*/
public static void showShort(Context context, int message)
{
if (isShow)
Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
}
/**
* 長時間顯示Toast
*
* @param context
* @param message
*/
public static void showLong(Context context, CharSequence message)
{
if (isShow)
Toast.makeText(context, message, Toast.LENGTH_LONG).show();
}
/**
* 長時間顯示Toast
*
* @param context
* @param message
*/
public static void showLong(Context context, int message)
{
if (isShow)
Toast.makeText(context, message, Toast.LENGTH_LONG).show();
}
/**
* 自定義顯示Toast時間
*
* @param context
* @param message
* @param duration
*/
public static void show(Context context, CharSequence message, int duration)
{
if (isShow)
Toast.makeText(context, message, duration).show();
}
/**
* 自定義顯示Toast時間
*
* @param context
* @param message
* @param duration
*/
public static void show(Context context, int message, int duration)
{
if (isShow)
Toast.makeText(context, message, duration).show();
}
}
也是非常簡單的一個封裝，能省則省了~~
package com.zhy.utils;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Map;
import android.content.Context;
import android.content.SharedPreferences;
public class SPUtils
{
/**
* 保存在手機裡面的文件名
*/
public static final String FILE_NAME = share_data;
/**
* 保存數據的方法，我們需要拿到保存數據的具體類型，然後根據類型調用不同的保存方法
*
* @param context
* @param key
* @param object
*/
public static void put(Context context, String key, Object object)
{
SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sp.edit();
if (object instanceof String)
{
editor.putString(key, (String) object);
} else if (object instanceof Integer)
{
editor.putInt(key, (Integer) object);
} else if (object instanceof Boolean)
{
editor.putBoolean(key, (Boolean) object);
} else if (object instanceof Float)
{
editor.putFloat(key, (Float) object);
} else if (object instanceof Long)
{
editor.putLong(key, (Long) object);
} else
{
editor.putString(key, object.toString());
}
SharedPreferencesCompat.apply(editor);
}
/**
* 得到保存數據的方法，我們根據默認值得到保存的數據的具體類型，然後調用相對於的方法獲取值
*
* @param context
* @param key
* @param defaultObject
* @return
*/
public static Object get(Context context, String key, Object defaultObject)
{
SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
Context.MODE_PRIVATE);
if (defaultObject instanceof String)
{
return sp.getString(key, (String) defaultObject);
} else if (defaultObject instanceof Integer)
{
return sp.getInt(key, (Integer) defaultObject);
} else if (defaultObject instanceof Boolean)
{
return sp.getBoolean(key, (Boolean) defaultObject);
} else if (defaultObject instanceof Float)
{
return sp.getFloat(key, (Float) defaultObject);
} else if (defaultObject instanceof Long)
{
return sp.getLong(key, (Long) defaultObject);
}
return null;
}
/**
* 移除某個key值已經對應的值
* @param context
* @param key
*/
public static void remove(Context context, String key)
{
SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sp.edit();
editor.remove(key);
SharedPreferencesCompat.apply(editor);
}
/**
* 清除所有數據
* @param context
*/
public static void clear(Context context)
{
SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sp.edit();
editor.clear();
SharedPreferencesCompat.apply(editor);
}
/**
* 查詢某個key是否已經存在
* @param context
* @param key
* @return
*/
public static boolean contains(Context context, String key)
{
SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
Context.MODE_PRIVATE);
return sp.contains(key);
}
/**
* 返回所有的鍵值對
*
* @param context
* @return
*/
public static Map getAll(Context context)
{
SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
Context.MODE_PRIVATE);
return sp.getAll();
}
/**
* 創建一個解決SharedPreferencesCompat.apply方法的一個兼容類
*
* @author zhy
*
*/
private static class SharedPreferencesCompat
{
private static final Method sApplyMethod = findApplyMethod();
/**
* 反射查找apply的方法
*
* @return
*/
@SuppressWarnings({ unchecked, rawtypes })
private static Method findApplyMethod()
{
try
{
Class clz = SharedPreferences.Editor.class;
return clz.getMethod(apply);
} catch (NoSuchMethodException e)
{
}
return null;
}
/**
* 如果找到則使用apply執行，否則使用commit
*
* @param editor
*/
public static void apply(SharedPreferences.Editor editor)
{
try
{
if (sApplyMethod != null)
{
sApplyMethod.invoke(editor);
return;
}
} catch (IllegalArgumentException e)
{
} catch (IllegalAccessException e)
{
} catch (InvocationTargetException e)
{
}
editor.commit();
}
}
}
注意一點，裡面所有的commit操作使用了SharedPreferencesCompat.apply進行了替代，目的是盡可能的使用apply代替commit
首先說下為什麼，因為commit方法是同步的，並且我們很多時候的commit操作都是UI線程中，畢竟是IO操作，盡可能異步；
所以我們使用apply進行替代，apply異步的進行寫入；
但是apply相當於commit來說是new API呢，為了更好的兼容，我們做了適配；
SharedPreferencesCompat也可以給大家創建兼容類提供了一定的參考~~
package com.zhy.utils;
import android.content.Context;
import android.util.TypedValue;
/**
* 常用單位轉換的輔助類
*
*
*
*/
public class DensityUtils
{
private DensityUtils()
{
/* cannot be instantiated */
throw new UnsupportedOperationException(cannot be instantiated);
}
/**
* dp轉px
*
* @param context
* @param val
* @return
*/
public static int dp2px(Context context, float dpVal)
{
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
dpVal, context.getResources().getDisplayMetrics());
}
/**
* sp轉px
*
* @param context
* @param val
* @return
*/
public static int sp2px(Context context, float spVal)
{
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP,
spVal, context.getResources().getDisplayMetrics());
}
/**
* px轉dp
*
* @param context
* @param pxVal
* @return
*/
public static float px2dp(Context context, float pxVal)
{
final float scale = context.getResources().getDisplayMetrics().density;
return (pxVal / scale);
}
/**
* px轉sp
*
* @param fontScale
* @param pxVal
* @return
*/
public static float px2sp(Context context, float pxVal)
{
return (pxVal / context.getResources().getDisplayMetrics().scaledDensity);
}
}
package com.zhy.utils;
import java.io.File;
import android.os.Environment;
import android.os.StatFs;
/**
* SD卡相關的輔助類
*
*
*
*/
public class SDCardUtils
{
private SDCardUtils()
{
/* cannot be instantiated */
throw new UnsupportedOperationException(cannot be instantiated);
}
/**
* 判斷SDCard是否可用
*
* @return
*/
public static boolean isSDCardEnable()
{
return Environment.getExternalStorageState().equals(
Environment.MEDIA_MOUNTED);
}
/**
* 獲取SD卡路徑
*
* @return
*/
public static String getSDCardPath()
{
return Environment.getExternalStorageDirectory().getAbsolutePath()
+ File.separator;
}
/**
* 獲取SD卡的剩余容量 單位byte
*
* @return
*/
public static long getSDCardAllSize()
{
if (isSDCardEnable())
{
StatFs stat = new StatFs(getSDCardPath());
// 獲取空閒的數據塊的數量
long availableBlocks = (long) stat.getAvailableBlocks() - 4;
// 獲取單個數據塊的大小（byte）
long freeBlocks = stat.getAvailableBlocks();
return freeBlocks * availableBlocks;
}
return 0;
}
/**
* 獲取指定路徑所在空間的剩余可用容量字節數，單位byte
*
* @param filePath
* @return 容量字節 SDCard可用空間，內部存儲可用空間
*/
public static long getFreeBytes(String filePath)
{
// 如果是sd卡的下的路徑，則獲取sd卡可用容量
if (filePath.startsWith(getSDCardPath()))
{
filePath = getSDCardPath();
} else
{// 如果是內部存儲的路徑，則獲取內存存儲的可用容量
filePath = Environment.getDataDirectory().getAbsolutePath();
}
StatFs stat = new StatFs(filePath);
long availableBlocks = (long) stat.getAvailableBlocks() - 4;
return stat.getBlockSize() * availableBlocks;
}
/**
* 獲取系統存儲路徑
*
* @return
*/
public static String getRootDirectoryPath()
{
return Environment.getRootDirectory().getAbsolutePath();
}
}
package com.zhy.utils;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Rect;
import android.util.DisplayMetrics;
import android.view.View;
import android.view.WindowManager;
/**
* 獲得屏幕相關的輔助類
*
*
*
*/
public class ScreenUtils
{
private ScreenUtils()
{
/* cannot be instantiated */
throw new UnsupportedOperationException(cannot be instantiated);
}
/**
* 獲得屏幕高度
*
* @param context
* @return
*/
public static int getScreenWidth(Context context)
{
WindowManager wm = (WindowManager) context
.getSystemService(Context.WINDOW_SERVICE);
DisplayMetrics outMetrics = new DisplayMetrics();
wm.getDefaultDisplay().getMetrics(outMetrics);
return outMetrics.widthPixels;
}
/**
* 獲得屏幕寬度
*
* @param context
* @return
*/
public static int getScreenHeight(Context context)
{
WindowManager wm = (WindowManager) context
.getSystemService(Context.WINDOW_SERVICE);
DisplayMetrics outMetrics = new DisplayMetrics();
wm.getDefaultDisplay().getMetrics(outMetrics);
return outMetrics.heightPixels;
}
/**
* 獲得狀態欄的高度
*
* @param context
* @return
*/
public static int getStatusHeight(Context context)
{
int statusHeight = -1;
try
{
Class clazz = Class.forName(com.android.internal.R$dimen);
Object object = clazz.newInstance();
int height = Integer.parseInt(clazz.getField(status_bar_height)
.get(object).toString());
statusHeight = context.getResources().getDimensionPixelSize(height);
} catch (Exception e)
{
e.printStackTrace();
}
return statusHeight;
}
/**
* 獲取當前屏幕截圖，包含狀態欄
*
* @param activity
* @return
*/
public static Bitmap snapShotWithStatusBar(Activity activity)
{
View view = activity.getWindow().getDecorView();
view.setDrawingCacheEnabled(true);
view.buildDrawingCache();
Bitmap bmp = view.getDrawingCache();
int width = getScreenWidth(activity);
int height = getScreenHeight(activity);
Bitmap bp = null;
bp = Bitmap.createBitmap(bmp, 0, 0, width, height);
view.destroyDrawingCache();
return bp;
}
/**
* 獲取當前屏幕截圖，不包含狀態欄
*
* @param activity
* @return
*/
public static Bitmap snapShotWithoutStatusBar(Activity activity)
{
View view = activity.getWindow().getDecorView();
view.setDrawingCacheEnabled(true);
view.buildDrawingCache();
Bitmap bmp = view.getDrawingCache();
Rect frame = new Rect();
activity.getWindow().getDecorView().getWindowVisibleDisplayFrame(frame);
int statusBarHeight = frame.top;
int width = getScreenWidth(activity);
int height = getScreenHeight(activity);
Bitmap bp = null;
bp = Bitmap.createBitmap(bmp, 0, statusBarHeight, width, height
- statusBarHeight);
view.destroyDrawingCache();
return bp;
}
}
package com.zhy.utils;
import android.content.Context;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
/**
* 跟App相關的輔助類
*
*
*
*/
public class AppUtils
{
private AppUtils()
{
/* cannot be instantiated */
throw new UnsupportedOperationException(cannot be instantiated);
}
/**
* 獲取應用程序名稱
*/
public static String getAppName(Context context)
{
try
{
PackageManager packageManager = context.getPackageManager();
PackageInfo packageInfo = packageManager.getPackageInfo(
context.getPackageName(), 0);
int labelRes = packageInfo.applicationInfo.labelRes;
return context.getResources().getString(labelRes);
} catch (NameNotFoundException e)
{
e.printStackTrace();
}
return null;
}
/**
* [獲取應用程序版本名稱信息]
*
* @param context
* @return 當前應用的版本名稱
*/
public static String getVersionName(Context context)
{
try
{
PackageManager packageManager = context.getPackageManager();
PackageInfo packageInfo = packageManager.getPackageInfo(
context.getPackageName(), 0);
return packageInfo.versionName;
} catch (NameNotFoundException e)
{
e.printStackTrace();
}
return null;
}
}
package com.zhy.utils;
import android.content.Context;
import android.view.inputmethod.InputMethodManager;
import android.widget.EditText;
/**
* 打開或關閉軟鍵盤
*
* @author zhy
*
*/
public class KeyBoardUtils
{
/**
* 打卡軟鍵盤
*
* @param mEditText
* 輸入框
* @param mContext
* 上下文
*/
public static void openKeybord(EditText mEditText, Context mContext)
{
InputMethodManager imm = (InputMethodManager) mContext
.getSystemService(Context.INPUT_METHOD_SERVICE);
imm.showSoftInput(mEditText, InputMethodManager.RESULT_SHOWN);
imm.toggleSoftInput(InputMethodManager.SHOW_FORCED,
InputMethodManager.HIDE_IMPLICIT_ONLY);
}
/**
* 關閉軟鍵盤
*
* @param mEditText
* 輸入框
* @param mContext
* 上下文
*/
public static void closeKeybord(EditText mEditText, Context mContext)
{
InputMethodManager imm = (InputMethodManager) mContext
.getSystemService(Context.INPUT_METHOD_SERVICE);
imm.hideSoftInputFromWindow(mEditText.getWindowToken(), 0);
}
}
package com.zhy.utils;
import android.app.Activity;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
/**
* 跟網絡相關的工具類
*
*
*
*/
public class NetUtils
{
private NetUtils()
{
/* cannot be instantiated */
throw new UnsupportedOperationException(cannot be instantiated);
}
/**
* 判斷網絡是否連接
*
* @param context
* @return
*/
public static boolean isConnected(Context context)
{
ConnectivityManager connectivity = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
if (null != connectivity)
{
NetworkInfo info = connectivity.getActiveNetworkInfo();
if (null != info && info.isConnected())
{
if (info.getState() == NetworkInfo.State.CONNECTED)
{
return true;
}
}
}
return false;
}
/**
* 判斷是否是wifi連接
*/
public static boolean isWifi(Context context)
{
ConnectivityManager cm = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
if (cm == null)
return false;
return cm.getActiveNetworkInfo().getType() == ConnectivityManager.TYPE_WIFI;
}
/**
* 打開網絡設置界面
*/
public static void openSetting(Activity activity)
{
Intent intent = new Intent(/);
ComponentName cm = new ComponentName(com.android.settings,
com.android.settings.WirelessSettings);
intent.setComponent(cm);
intent.setAction(android.intent.action.VIEW);
activity.startActivityForResult(intent, 0);
}
}
package com.zhy.utils;
import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.URL;
/**
* Http請求的工具類
*
* @author zhy
*
*/
public class HttpUtils
{
private static final int TIMEOUT_IN_MILLIONS = 5000;
public interface CallBack
{
void onRequestComplete(String result);
}
/**
* 異步的Get請求
*
* @param urlStr
* @param callBack
*/
public static void doGetAsyn(final String urlStr, final CallBack callBack)
{
new Thread()
{
public void run()
{
try
{
String result = doGet(urlStr);
if (callBack != null)
{
callBack.onRequestComplete(result);
}
} catch (Exception e)
{
e.printStackTrace();
}
};
}.start();
}
/**
* 異步的Post請求
* @param urlStr
* @param params
* @param callBack
* @throws Exception
*/
public static void doPostAsyn(final String urlStr, final String params,
final CallBack callBack) throws Exception
{
new Thread()
{
public void run()
{
try
{
String result = doPost(urlStr, params);
if (callBack != null)
{
callBack.onRequestComplete(result);
}
} catch (Exception e)
{
e.printStackTrace();
}
};
}.start();
}
/**
* Get請求，獲得返回數據
*
* @param urlStr
* @return
* @throws Exception
*/
public static String doGet(String urlStr)
{
URL url = null;
HttpURLConnection conn = null;
InputStream is = null;
ByteArrayOutputStream baos = null;
try
{
url = new URL(urlStr);
conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(TIMEOUT_IN_MILLIONS);
conn.setConnectTimeout(TIMEOUT_IN_MILLIONS);
conn.setRequestMethod(GET);
conn.setRequestProperty(accept, */*);
conn.setRequestProperty(connection, Keep-Alive);
if (conn.getResponseCode() == 200)
{
is = conn.getInputStream();
baos = new ByteArrayOutputStream();
int len = -1;
byte[] buf = new byte[128];
while ((len = is.read(buf)) != -1)
{
baos.write(buf, 0, len);
}
baos.flush();
return baos.toString();
} else
{
throw new RuntimeException( responseCode is not 200 ... );
}
} catch (Exception e)
{
e.printStackTrace();
} finally
{
try
{
if (is != null)
is.close();
} catch (IOException e)
{
}
try
{
if (baos != null)
baos.close();
} catch (IOException e)
{
}
conn.disconnect();
}
return null ;
}
/**
* 向指定 URL 發送POST方法的請求
*
* @param url
* 發送請求的 URL
* @param param
* 請求參數，請求參數應該是 name1=value1&name2=value2 的形式。
* @return 所代表遠程資源的響應結果
* @throws Exception
*/
public static String doPost(String url, String param)
{
PrintWriter out = null;
BufferedReader in = null;
String result = ;
try
{
URL realUrl = new URL(url);
// 打開和URL之間的連接
HttpURLConnection conn = (HttpURLConnection) realUrl
.openConnection();
// 設置通用的請求屬性
conn.setRequestProperty(accept, */*);
conn.setRequestProperty(connection, Keep-Alive);
conn.setRequestMethod(POST);
conn.setRequestProperty(Content-Type,
application/x-www-form-urlencoded);
conn.setRequestProperty(charset, utf-8);
conn.setUseCaches(false);
// 發送POST請求必須設置如下兩行
conn.setDoOutput(true);
conn.setDoInput(true);
conn.setReadTimeout(TIMEOUT_IN_MILLIONS);
conn.setConnectTimeout(TIMEOUT_IN_MILLIONS);
if (param != null && !param.trim().equals())
{
// 獲取URLConnection對象對應的輸出流
out = new PrintWriter(conn.getOutputStream());
// 發送請求參數
out.print(param);
// flush輸出流的緩沖
out.flush();
}
// 定義BufferedReader輸入流來讀取URL的響應
in = new BufferedReader(
new InputStreamReader(conn.getInputStream()));
String line;
while ((line = in.readLine()) != null)
{
result += line;
}
} catch (Exception e)
{
e.printStackTrace();
}
// 使用finally塊來關閉輸出流、輸入流
finally
{
try
{
if (out != null)
{
out.close();
}
if (in != null)
{
in.close();
}
} catch (IOException ex)
{
ex.printStackTrace();
}
}
return result;
}
}
android仿愛奇藝加載動畫實例
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