Android Lock Screen Orientation

一些与屏幕有关的基础知识:

//这个是手机屏幕的旋转角度
final int rotation = this.getWindowManager().getDefaultDisplay().getOrientation();

rotation值有：
Surface.ROTATION_0
Surface.ROTATION_90
Surface.ROTATION_180
Surface.ROTATION_270

//这个是读取当前Activity 的屏幕方向
final int orientation = this.getResources().getConfiguration().orientation;

orientation值有:
Configuration.ORIENTATION_PORTRAIT
Configuration.ORIENTATION_LANDSCAPE

//这个是设置Activity 的屏幕方向,与AndroidManifest.xml中的android:screenOrientation="landscape"配置等同
this.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE)

　　

Build.VERSION:Various version strings.

android.os.Build.VERSION.SDK_INT:The user-visible SDK version of the framework; its possible values are defined in

Build.VERSION_CODES

.

Build.VERSION_CODES:Enumeration of the currently known SDK version codes. These are the values that can be found in

SDK

. Version numbers increment monotonically with each official platform release.

android.os.Build.VERSION_CODES.FROYO:June 2010: Android 2.2

The REVERSE_LANDSCAPE and REVERSE_PORTRAIT appear after android 2.3,so we can not use them on android 2.2 and former devices.

private void disableRotation()
{
final int orientation = getResources().getConfiguration().orientation;
final int rotation = getWindowManager().getDefaultDisplay().getOrientation();

// Copied from Android docs, since we don't have these values in Froyo 2.2
int SCREEN_ORIENTATION_REVERSE_LANDSCAPE = 8;
int SCREEN_ORIENTATION_REVERSE_PORTRAIT = 9;

if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.FROYO)
{
SCREEN_ORIENTATION_REVERSE_LANDSCAPE = ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE;
SCREEN_ORIENTATION_REVERSE_PORTRAIT = ActivityInfo.SCREEN_ORIENTATION_PORTRAIT;
}

if (rotation == Surface.ROTATION_0 || rotation == Surface.ROTATION_90)
{
if (orientation == Configuration.ORIENTATION_PORTRAIT){
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
}
else if (orientation == Configuration.ORIENTATION_LANDSCAPE){
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
}
}
else if (rotation == Surface.ROTATION_180 || rotation == Surface.ROTATION_270)
{
if (orientation == Configuration.ORIENTATION_PORTRAIT){
setRequestedOrientation(SCREEN_ORIENTATION_REVERSE_PORTRAIT);
}
else if (orientation == Configuration.ORIENTATION_LANDSCAPE){
setRequestedOrientation(SCREEN_ORIENTATION_REVERSE_LANDSCAPE);
}
}
}

enable the rotation:

setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED);

About the rotation and orientation,on some devices,the Surface.ROTATION_0 corresponds to ORIENTATION_LANDSCAPE,but others,may ORIENTATION_PORTRAIT.So we have to so some work to judge it.

However,for some reason ROTATION_90 corresponds to SCREEN_ORIENTATION_REVERSE_PORTRAIT on the Xoom if you use the above method.So another method appears:

private void disableRotation()
{
final int orientation = getResources().getConfiguration().orientation;
final int rotation = getWindowManager().getDefaultDisplay().getOrientation();

// Copied from Android docs, since we don't have these values in Froyo 2.2
int SCREEN_ORIENTATION_REVERSE_LANDSCAPE = 8;
int SCREEN_ORIENTATION_REVERSE_PORTRAIT = 9;

if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.FROYO)
{
SCREEN_ORIENTATION_REVERSE_LANDSCAPE = ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE;
SCREEN_ORIENTATION_REVERSE_PORTRAIT = ActivityInfo.SCREEN_ORIENTATION_PORTRAIT;
}

if (orientation == Configuration.ORIENTATION_PORTRAIT) {
if (rotation == Surface.ROTATION_0|| rotation == Surface.ROTATION_270)
// 0 for phone, 270 for tablet
{
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
} else {
setRequestedOrientation(SCREEN_ORIENTATION_REVERSE_PORTRAIT);
}
} else {
if (rotation == Surface.ROTATION_90|| rotation == Surface.ROTATION_0)
// 90 for phone, 0 for tablet
{
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
} else {
setRequestedOrientation(SCREEN_ORIENTATION_REVERSE_LANDSCAPE);
}
}

}

i'm not sure the note "//0 for phone, 270 for tablet" and "// 90 for phone, 0 for tablet" are right on any device,but at least it works well in my device.so I use the latter one.

When you want to disable/enable the autorotation of the device ,you have to write the settings.