Android 一些功能代码，Android功能代码,全屏javareques

Android 一些功能代码，Android功能代码,全屏javareques

全屏javarequestWindowFeature(Window.FEATURE_NO_TITLE); // 无标题栏需要在setContentView之前getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);也可以在manifest中：```java<Activity android:theme="@android:style/Theme.NoTitleBar.Fullscreen".. />

横屏```java>setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);```安装apk```javaprivate void install(File file) {    Intent intent = new Intent();    intent.setAction(Intent.ACTION_VIEW);//  intent.setData(Uri.fromFile(file));//  intent.setType("application/vnd.android.package-archive"); //mime的数据类型 plain/text image/jpeg     intent.setDataAndType(Uri.fromFile(file), "application/vnd.android.package-archive");//该mime 表示 .apk 文件类型    startActivity(intent);}```精确获取屏幕尺寸（例如：3.5、4.0、5.0寸屏幕） ```javapublic static double getScreenPhysicalSize(Activity ctx) {    DisplayMetrics dm = new DisplayMetrics();    ctx.getWindowManager().getDefaultDisplay().getMetrics(dm);    //对角线像素长    double diagonalPixels = Math.sqrt(Math.pow(dm.widthPixels, 2) + Math.pow(dm.heightPixels, 2));    return diagonalPixels / (160 * dm.density); //160像素，density=1}

启动Apk的默认Activity

public static void startApkActivity(final Context ctx, String packageName) {    PackageManager pm = ctx.getPackageManager();    PackageInfo pi;    try {    <span style="white-space:pre">  </span>pi = pm.getPackageInfo(packageName, 0);        Intent intent = new Intent(Intent.ACTION_MAIN, null);        intent.addCategory(Intent.CATEGORY_LAUNCHER);        intent.setPackage(pi.packageName);        List<ResolveInfo> apps = pm.queryIntentActivities(intent, 0);        ResolveInfo ri = apps.iterator().next();        if (ri != null) {            String className = ri.activityInfo.name;            intent.setComponent(new ComponentName(packageName, className));            ctx.startActivity(intent);        }    } catch (NameNotFoundException e) {        Log.e("startActivity", e.getMessage());    }}

根据手机的分辨率从 dp 的单位 转成为 px(像素)

public static int dip2px(Context context, float dpValue) {      final float scale = context.getResources().getDisplayMetrics().density;      return (int) (dpValue * scale + 0.5f);  }  

根据手机的分辨率从px(像素) 的单位 转成为dp

public static int px2dip(Context context, float pxValue) {  <span style="white-space:pre">  </span>final float scale = context.getResources().getDisplayMetrics().density;      return (int) (pxValue / scale + 0.5f);  }  ```重启应用程序```javaIntent i = getBaseContext().getPackageManager()//    .getLaunchIntentForPackage(getBaseContext().getPackageName()); i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); startActivity(i);

判断字宽

public static float GetTextWidth(String text, float size) {    TextPaint fontPaint = new TextPaint();    fontPaint.setTextSize(size);    return fontPaint.measureText(text);}