I write a simple game with the following structure. Main xml layout have user View:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/menuRL"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<com.sokolovlev.UFOtest03.MenuView
android:id="@+id/menuView"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />
</RelativeLayout>
This View have two files. First is user MenuView:
package com.sokolovlev.UFOtest03;
import android.content.Context;
import android.util.AttributeSet;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
public class MenuView extends SurfaceView implements SurfaceHolder.Callback
{
private SurfaceHolder mSurfaceHolder; //Draw surface
public static MenuManager mMenuManager; //Draw manager
public MenuView(Context context, AttributeSet attrs)
{
super(context, attrs);
// Surface events registration
mSurfaceHolder = getHolder();
mSurfaceHolder.addCallback(this);
mMenuManager = new MenuManager(mSurfaceHolder, context);
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height)
{
mMenuManager.initPositions(height, width);
}
@SuppressWarnings("static-access")
@Override
public void surfaceCreated(SurfaceHolder holder)
{
mMenuManager.setRunning(true);
try
{
mMenuManager.start();
}
catch (Exception e) { }
}
@SuppressWarnings("static-access")
@Override
public void surfaceDestroyed(SurfaceHolder holder)
{
boolean retry = true;
mMenuManager.setRunning(false);
while (retry)
{
try
{
mMenuManager.join();
retry = false;
}
catch (InterruptedException e) { }
}
}
}
And second file is this draw manager:
package com.sokolovlev.UFOtest03;
import ...
public class MenuManager extends Thread
{
private SurfaceHolder mSurfaceHolder;
private static boolean mRunning;
private int _screenHeight;
private int _screenWidth;
private ...
Context c;
private ...
public MenuManager(SurfaceHolder surfaceHolder, Context context)
{
mSurfaceHolder = surfaceHolder;
mRunning = false;
c = context;
...
}
public static void setRunning(boolean running)
{
mRunning = running;
}
@Override
public void run()
{
while (mRunning)
{
Canvas canvas = null;
try
{
// подготовка Canvas-а
canvas = mSurfaceHolder.lockCanvas();
canvas.drawRGB(0, 0, 0);
synchronized (mSurfaceHolder)
{
//All drawing
}
}
catch (Exception e) { }
finally
{
if (canvas != null)
{
mSurfaceHolder.unlockCanvasAndPost(canvas);
}
}
}
}
}
Everything works fine! (step №1) But if I press central button, or I have incoming call, or I call task manager (step №2) and go back to my app - I haven't my drawing, only black screen (step №3). But if I go next to step №2 and then in my app, I see that everything works.
I don't understand, where there is a reloading which influences such on my drawings! Help please!