我设计了一个简单的多点触控系统，可以跟踪手指位置及其在屏幕上的状态。设计程序的方式，当两个手指放下时，根据放置顺序为它们分配一个数字。如果手指抬起，手指2仍称为手指2。
此代码在部分时间内完美运行。这意味着我将在测试中运行我的应用程序，有时每次都会进行多点触控，有时使用多个手指会使应用程序完全失败。它不规则可靠。
我很好奇这是硬件错误，还是我处理触摸输入的方式。来源可在下面找到。
感谢您提供的任何帮助！
-Nathan Tornquist
编辑：我认为问题可能与eventListeners的注册和取消注册方式有关。有时应用程序会崩溃，并在我重新打开它时再次完美运行。
EDIT2：问题在于程序的不规范程度。有时当我打开它时，它会完美地跟踪手指。放下的第一根手指保持1号，第二根手指保持2号等等。无论你是否在放置2后抬起手指1，数字都会保持分配状态。其他时候你会放两个手指，哪个手指是1，哪个是2个变化。应用程序似乎忘记了它们，当您将手指放在屏幕上时数字会切换。
EDIT3：我尝试过“触摸屏助推器”试图让屏幕始终正确响应。它没有解决问题。
EDIT4：经过更多测试后，这显然是代码错误。首次启动应用程序时，它始终完美运行。设备锁定后（当活动暂停时）然后解锁（当活动恢复时）多点触控停止工作，我得到一个适用于单点触控的应用程序，并且被多点触控困惑。
MultitouchGameFixActivity.java
package com.nathantornquist.multitouchgame;
import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.os.Bundle;
import android.view.Window;
import android.view.WindowManager;
public class MultiTouchGameFixActivity extends Activity{
/** Called when the activity is first created. */
MainGamePanel viewPanel;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//Window state functions.
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
//This works without declaring a viewPanel instance here.
//The instance declaration is needed to pass the
//onPause and onResume commands though.
viewPanel = new MainGamePanel(this);
setContentView(viewPanel);
}
//Restarts the accelerometer after onPause
protected void onResume() {
super.onResume();
viewPanel.resume(this);
}
//Standard Method run when the Application loses focus.
//This runs the pause() function in the viewPanel so that
//the accelerometer can be paused.
protected void onPause() {
super.onPause();
viewPanel.pause();
}
protected void onDestroy() {
super.onDestroy();
viewPanel.destroy();
}
}
MainThread.java
package com.nathantornquist.multitouchgame;
import com.nathantornquist.multitouchgame.MainGamePanel;
import android.graphics.Canvas;
import android.view.SurfaceHolder;
public class MainThread extends Thread {
private SurfaceHolder surfaceHolder;
private MainGamePanel gamePanel;
private boolean running;
public boolean pleaseWait = true;
public void setRunning(boolean running) {
this.running = running;
}
public MainThread(SurfaceHolder surfaceHolder, MainGamePanel gamePanel) {
super();
this.surfaceHolder = surfaceHolder;
this.gamePanel = gamePanel;
}
@Override
public void run()
{
Canvas canvas;
while (running) {
if(!pleaseWait) {
canvas = null;
// try locking the canvas for exclusive pixel editing on the surface
try {
canvas = this.surfaceHolder.lockCanvas();
synchronized (surfaceHolder) {
// update game state
this.gamePanel.update();
// draws the canvas on the panel
this.gamePanel.onDraw(canvas);
}
} finally {
// in case of an exception the surface is not left in
// an inconsistent state
if (canvas != null) {
surfaceHolder.unlockCanvasAndPost(canvas);
}
} // end finally
}
else {
synchronized (this) {
try {
wait();
} catch (Exception e) { }
}
}
}
}
}
MainGamePanel.java
package com.nathantornquist.multitouchgame;
import android.R.string;
import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.util.Log;
import android.view.Display;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
public class MainGamePanel extends SurfaceView implements SensorEventListener, SurfaceHolder.Callback
{
//Variable Declarations.
private MainThread thread;
public int screenWidth;
public int screenHeight;
private SensorManager mSensorManager;
private Sensor mAccelerometer;
Paint paint;
public int fingerOneDown;
public int fingerTwoDown;
public int fingerThreeDown;
public int fingerFourDown;
public float fingerOneX;
public float fingerOneY;
public float fingerTwoX;
public float fingerTwoY;
public float fingerThreeX;
public float fingerThreeY;
public float fingerFourX;
public float fingerFourY;
public MainGamePanel(Context context)
{
super(context);
getHolder().addCallback(this);
thread = new MainThread(getHolder(),this);
paint = new Paint();
paint.setAntiAlias(true);
Display display = ((Activity) context).getWindowManager().getDefaultDisplay();
screenWidth = display.getWidth();
screenHeight = display.getHeight();
mSensorManager = (SensorManager) context.getSystemService(Context.SENSOR_SERVICE);
mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
mSensorManager.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_FASTEST);
fingerOneDown = 0;
fingerTwoDown = 0;
fingerThreeDown = 0;
fingerFourDown = 0;
fingerOneX = 0;
fingerOneY = 0;
fingerTwoX = 0;
fingerTwoY = 0;
fingerThreeX = 0;
fingerThreeY = 0;
fingerFourX = 0;
fingerFourY = 0;
setFocusable(true);
thread.setRunning(true);
thread.start();
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
//continue the thread
synchronized (thread) {
thread.pleaseWait = false;
thread.notifyAll();
}
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
//pause the thread
synchronized (thread) {
thread.pleaseWait = true;
}
}
@Override
public boolean onTouchEvent(MotionEvent event) {
int action = event.getAction() & MotionEvent.ACTION_MASK;
int pointerIndex = (event.getAction() & MotionEvent.ACTION_POINTER_ID_MASK) >> MotionEvent.ACTION_POINTER_ID_SHIFT;
int pointerId = event.getPointerId(pointerIndex);
switch (action) {
case MotionEvent.ACTION_DOWN:
case MotionEvent.ACTION_POINTER_DOWN:
Log.d("pointer id - down",Integer.toString(pointerId));
if (pointerId == 0)
{
fingerOneDown = 1;
fingerOneX = event.getX(pointerIndex);
fingerOneY = event.getY(pointerIndex);
}
if (pointerId == 1)
{
fingerTwoDown = 1;
fingerTwoX = event.getX(pointerIndex);
fingerTwoY = event.getY(pointerIndex);
}
if(pointerId == 2)
{
fingerThreeDown = 1;
fingerThreeX = event.getX(pointerIndex);
fingerThreeY = event.getY(pointerIndex);
}
if(pointerId == 3)
{
fingerFourDown = 1;
fingerFourX = event.getX(pointerIndex);
fingerFourY = event.getY(pointerIndex);
}
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_POINTER_UP:
case MotionEvent.ACTION_CANCEL:
Log.d("pointer id - cancel",Integer.toString(pointerId));
if (pointerId == 0)
{
fingerOneDown = 0;
fingerOneX = event.getX(pointerIndex);
fingerOneY = event.getY(pointerIndex);
}
if (pointerId == 1)
{
fingerTwoDown = 0;
fingerTwoX = event.getX(pointerIndex);
fingerTwoY = event.getY(pointerIndex);
}
if(pointerId == 2)
{
fingerThreeDown = 0;
fingerThreeX = event.getX(pointerIndex);
fingerThreeY = event.getY(pointerIndex);
}
if(pointerId == 3)
{
fingerFourDown = 0;
fingerFourX = event.getX(pointerIndex);
fingerFourY = event.getY(pointerIndex);
}
break;
case MotionEvent.ACTION_MOVE:
int pointerCount = event.getPointerCount();
for(int i = 0; i < pointerCount; ++i)
{
pointerIndex = i;
pointerId = event.getPointerId(pointerIndex);
Log.d("pointer id - move",Integer.toString(pointerId));
if(pointerId == 0)
{
fingerOneDown = 1;
fingerOneX = event.getX(pointerIndex);
fingerOneY = event.getY(pointerIndex);
}
if(pointerId == 1)
{
fingerTwoDown = 1;
fingerTwoX = event.getX(pointerIndex);
fingerTwoY = event.getY(pointerIndex);
}
if(pointerId == 2)
{
fingerThreeDown = 1;
fingerThreeX = event.getX(pointerIndex);
fingerThreeY = event.getY(pointerIndex);
}
if(pointerId == 3)
{
fingerFourDown = 1;
fingerFourX = event.getX(pointerIndex);
fingerFourY = event.getY(pointerIndex);
}
}
break;
}
return true;
}
@Override
protected void onDraw(Canvas canvas)
{
paint.setColor(Color.WHITE);
paint.setStyle(Style.FILL);
canvas.drawPaint(paint);
if (fingerOneDown == 1)
{
paint.setColor(Color.BLUE);
paint.setTextSize(20);
canvas.drawText("1", fingerOneX, fingerOneY - 30, paint);
}
if (fingerTwoDown == 1)
{
paint.setColor(Color.RED);
paint.setTextSize(20);
canvas.drawText("2", fingerTwoX, fingerTwoY - 30, paint);
}
if (fingerThreeDown == 1)
{
paint.setColor(Color.GREEN);
paint.setTextSize(20);
canvas.drawText("3", fingerThreeX, fingerThreeY - 30, paint);
}
if (fingerFourDown == 1)
{
paint.setColor(Color.BLACK);
paint.setTextSize(20);
canvas.drawText("4", fingerFourX, fingerFourY - 30, paint);
}
}
public void update() {
}
@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
@Override
public void onSensorChanged(SensorEvent event) {
}
public void pause() {
mSensorManager.unregisterListener(this);
}
public void resume(Context context) {
mSensorManager.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_FASTEST);
}
public void destroy() {
thread.setRunning(false);
if (thread != null)
{
Thread killThread = thread;
thread = null;
killThread.interrupt();
}
}
}
答案 0 :(得分：0)
我会抛出一些想法，即使我的安卓技能有点缺乏......
你是如何测试的？在一个真实的设备上我猜？可以在模拟器上测试吗？看起来它很容易出现硬件问题。
如果有一个小故障，屏幕即使只是一个毫秒也会失去手指的轨迹，不会因为手指的索引而重新开始吗？如果是这种情况，它会非常随机地对手指进行编号，从而导致您遇到的问题。
一些想法：
MotionEvent.ACTION_POINTER_UP是您应该记录的事件。事实上，我为每个可能的事件添加一个日志，只是为了看看发生了什么。 我想您一直在查看Android developer blog上的多点触控示例，以确保您正确使用这些API？
希望它可以给你一些帮助。
答案 1 :(得分：0)
通过禁用WidgetLocker解决了该问题。该应用程序似乎偶尔搞乱一些程序。当我在玩游戏时锁定屏幕时，我也注意到了其他应用程序中的问题。