从景观的Android移动为纵向(反之亦然),使用相机时速度太慢? [英] Android move from Landscape to Portrait (or vice versa) when using camera is too slow?
问题描述
我有一个 DrawerLayout
包含一个的FrameLayout
和的ListView
在我的应用程序,我必须展示在的FrameLayout
,我已经做了细相机(如下code)和照相机工作正常。从纵向转向(右横向方向或左横向),反之亦然时,它以移动很长的时间进行更改的问题是,从右键横向方向或向左移动时的问题不会出现-landscape方向,反之亦然。
I have a DrawerLayout
which contains a FrameLayout
and ListView
in my app, I have to show the camera in the FrameLayout
, I've done that fine (as following code) and the camera works correctly. The problem is when moving from portrait orientation to (right-Landscape orientation or left-landscape orientation), or vice versa, it take the mobile a long time to make changes, the problem does not appear when moving from right-Landscape orientation or left-landscape orientation or vice versa.
我怎么能做出这样的操作一样快,我可以吗?
How could I make this operation as fast as I can?
public class ShowCamera extends SurfaceView implements SurfaceHolder.Callback{
//This ShowCamera class is a helpful class
private SurfaceHolder holdMe;
private Camera theCamera;
public ShowCamera(Context context,Camera camera) {
super(context);
theCamera = camera;
holdMe = getHolder();
holdMe.addCallback(this);
}
@Override
public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
try {
theCamera.setPreviewDisplay(holder);
theCamera.startPreview();
synchronized (holder) {
}
} catch (Exception e) {}
}
@Override
public void surfaceDestroyed(SurfaceHolder arg0) {
holdMe.removeCallback(this);
theCamera.release();
}
}
结果现在原班是:结果
}
Now the original class is:
public class MainActivity extends Activity {
private DrawerLayout mDrawerLayout;
private ListView mDrawerList;
String[] options = {"op1", "op2", "op3", "op4", "op5"}; //for the DrawerLayout
int[] icons = { 0,R.drawable.hospital,R.drawable.education,R.drawable.police,R.drawable.food}; //for the DrawerLayout
private Camera cameraObject;
private ShowCamera showCamera;
public static Camera getCamIfAvailable(){
Camera cam = null;
try { cam = Camera.open();}
catch (Exception e){}
return cam;
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
cameraObject = getCamIfAvailable();
new Thread(new Runnable()
{
int rotation = getWindowManager().getDefaultDisplay().getRotation();
@Override
public void run()
{
switch(rotation){
case 0: // portrait
cameraObject.setDisplayOrientation(90);
break;
case 1: // left Landscape
cameraObject.setDisplayOrientation(0);
break;
case 3: //right Landscape
cameraObject.setDisplayOrientation(180);
break;
}
}
}).start();
showCamera = new ShowCamera(this, cameraObject);
FrameLayout preview = (FrameLayout) findViewById(R.id.content_frame);
preview.addView(showCamera);
//.
//.
//.
//.
//. Here, code for Drawerlayout no problrm
//.
//.
//.
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
// Pass any configuration change to the drawer toggls
mDrawerToggle.onConfigurationChanged(newConfig);
// Checks the orientation of the screen
if (newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE) {
Toast.makeText(this, "landscape", Toast.LENGTH_SHORT).show();
} else if (newConfig.orientation == Configuration.ORIENTATION_PORTRAIT){
Toast.makeText(this, "portrait", Toast.LENGTH_SHORT).show();
}
}
.
.
.
.
} // End of the class MainActivity
此外,我已经把清单文件中的以下内容作为第一个<一个href=\"http://stackoverflow.com/questions/5726657/how-to-detect-orientation-change-in-layout-in-android\">answer这里提到:结果
<activity android:name=".MyActivity"
android:configChanges="orientation|screenSize"
android:label="@string/app_name">
任何帮助将AP preciated。
Any help will be appreciated.
推荐答案
Camera.open()
是系统中的重操作。它只是触发时的配置变化正在发生,当你旋转你的设备从横向到纵向,反之亦然,如。
当翻转装置(从纵向到逆转肖像,或景观逆转横向)这不会触发配置更改,只有屏幕渲染翻转,因此,你不叫 Camera.open( )
一次。
Camera.open()
is an heavy operation for the system. It is only triggered when a configuration change is happening, such as when you rotate your device from landscape to portrait and vice-versa.
When flipping the device (from portrait to reversed portrait, or from landscape to reversed landscape) this doesn't trigger a configuration change, only the screen rendering is flipped and therefore you don't call Camera.open()
again.
所以,你将无法使其更快(尽管我建议你看一看的systrace工具来看看什么是真正发生的事情,当你旋转屏幕)。
So, you won't be able to make it faster (even though I recommend you to take a look at the systrace tool to see what's really happening when you rotate your screen).
不过,我强烈建议你尝试调用 Camera.open()
从后台线程,以避免冻结UI。
But, I strongly encourage you to try calling the Camera.open()
from a background Thread to avoid freezing the UI.
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