我尝试GestureDetector在我的应用程序中添加一个，这样当用户从左向右滑动时，它会转到下一个活动，而当从右向左滑动时，它会转到上一个活动。现在，在此之前，我想使用 toast 对其进行测试。我构建了代码并对其进行了测试，但是当我只是触摸屏幕时它就会崩溃。我什至不必刷卡。这是我的代码：
package com.cydeon.plasmamodz;
import java.io.File;
import com.koushikdutta.urlimageviewhelper.UrlImageViewHelper;
import android.app.ActionBar;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnTouchListener;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.Toast;
import android.view.GestureDetector.OnGestureListener;
import android.view.GestureDetector;
import android.os.*;
public class Softkeys extends Activity implements OnClickListener, OnGestureListener{
private GestureDetector gestureDetector;
private static final int SWIPE_MIN_DISTANCE = 150;
private static final int SWIPE_THRESHOLD_VELOCITY = 100;
/* (non-Javadoc)
* @see android.app.Activity#onCreate(android.os.Bundle)
*/
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.themes);
ActionBar actionBar = getActionBar();
actionBar.hide();
RelativeLayout ll = (RelativeLayout) findViewById(R.id.myLayout);
final GestureDetector gestureDetector = new GestureDetector(Softkeys.this, this);
OnTouchListener gestureListener = new View.OnTouchListener() {
public boolean onTouch(View v, MotionEvent event) {
return gestureDetector.onTouchEvent(event);
}
};
ll.setOnTouchListener(gestureListener);
int [] viewIds = new int [] {R.id.b1, R.id.b2, R.id.b3, R.id.b4, R.id.b5, R.id.b6, R.id.b7, R.id.b8, R.id.b9, R.id.b10, R.id.b11, R.id.b12, R.id.b13, R.id.b13, R.id.b14, R.id.b15, R.id.b16, R.id.b17, R.id.b18, R.id.b19, R.id.b20, R.id.b21, R.id.b22, R.id.b23, R.id.b24, R.id.b25, R.id.b26, R.id.b27, R.id.b28, R.id.b29, R.id.b30};
for(int i = 0; i < viewIds.length; i++){
View v = findViewById(viewIds[i]);
if (v != null) {
v.setVisibility(0);
}
}
Button stock = (Button) findViewById(R.id.b1);
stock.setBackgroundResource(R.drawable.soft_stock);
Button stockBlue = (Button) findViewById(R.id.b2);
stockBlue.setBackgroundResource(R.drawable.soft_stock_blue);
Button green = (Button) findViewById(R.id.b3);
green.setBackgroundResource(R.drawable.soft_green);
Button pink = (Button) findViewById(R.id.b4);
pink.setBackgroundResource(R.drawable.soft_pink);
Button purple = (Button) findViewById(R.id.b5);
purple.setBackgroundResource(R.drawable.soft_purple);
Button yellow = (Button) findViewById(R.id.b6);
yellow.setBackgroundResource(R.drawable.soft_yellow);
Button red = (Button) findViewById(R.id.b7);
red.setBackgroundResource(R.drawable.soft_red);
Button galaxy = (Button) findViewById(R.id.b8);
galaxy.setBackgroundResource(R.drawable.soft_galaxy);
Button galaxyBlue = (Button) findViewById(R.id.b9);
galaxyBlue.setBackgroundResource(R.drawable.soft_galaxy_blue);
Button reflect = (Button) findViewById(R.id.b10);
reflect.setBackgroundResource(R.drawable.soft_reflect);
Button reflectBlue = (Button) findViewById(R.id.b11);
reflectBlue.setBackgroundResource(R.drawable.soft_reflect_blue);
Button razor = (Button) findViewById(R.id.b12);
razor.setBackgroundResource(R.drawable.soft_razor);
Button razorBlue = (Button) findViewById(R.id.b13);
razorBlue.setBackgroundResource(R.drawable.soft_razor_blue);
Button small = (Button) findViewById(R.id.b14);
small.setBackgroundResource(R.drawable.soft_small);
Button smallBlue = (Button) findViewById(R.id.b15);
smallBlue.setBackgroundResource(R.drawable.soft_small_blue);
Button smallReflect = (Button) findViewById(R.id.b16);
smallReflect.setBackgroundResource(R.drawable.soft_small_reflect);
Button smallReflectBlue = (Button) findViewById(R.id.b17);
smallReflectBlue.setBackgroundResource(R.drawable.soft_small_reflect_blue);
Button xperia = (Button) findViewById(R.id.b18);
xperia.setBackgroundResource(R.drawable.soft_xperia);
Button blueXperia = (Button) findViewById(R.id.b19);
blueXperia.setBackgroundResource(R.drawable.soft_xperia_blue);
Button zte = (Button) findViewById(R.id.b20);
zte.setBackgroundResource(R.drawable.soft_zte);
Button zteBlue = (Button) findViewById(R.id.b21);
zteBlue.setBackgroundResource(R.drawable.soft_zte_blue);
Button college = (Button) findViewById(R.id.b22);
college.setBackgroundResource(R.drawable.soft_college);
Button collegeBlue = (Button) findViewById(R.id.b23);
collegeBlue.setBackgroundResource(R.drawable.soft_college_blue);
Button defused = (Button) findViewById(R.id.b24);
defused.setBackgroundResource(R.drawable.soft_defused);
Button defusedBlue = (Button) findViewById(R.id.b25);
defusedBlue.setBackgroundResource(R.drawable.soft_defused_blue);
Button droid = (Button) findViewById(R.id.b26);
droid.setBackgroundResource(R.drawable.soft_droid);
Button droidBlue = (Button) findViewById(R.id.b27);
droidBlue.setBackgroundResource(R.drawable.soft_droid_blue);
Button pixel = (Button) findViewById(R.id.b28);
pixel.setBackgroundResource(R.drawable.soft_pixel);
Button pixelBlue = (Button) findViewById(R.id.b29);
pixelBlue.setBackgroundResource(R.drawable.soft_pixel_blue);
Button facebook = (Button) findViewById(R.id.b30);
facebook.setBackgroundResource(R.drawable.soft_facebook);
int [] viewIds2 = new int [] {R.id.b1, R.id.b2, R.id.b3, R.id.b4, R.id.b5, R.id.b6, R.id.b7, R.id.b8, R.id.b9, R.id.b10, R.id.b11, R.id.b12, R.id.b13, R.id.b13, R.id.b14, R.id.b15, R.id.b16, R.id.b17, R.id.b18, R.id.b19, R.id.b20, R.id.b21, R.id.b22, R.id.b23, R.id.b24, R.id.b25, R.id.b26, R.id.b27, R.id.b28, R.id.b29, R.id.b30};
for(int i = 0; i < viewIds2.length; i++){
View v = findViewById(viewIds2[i]);
if (v != null) {
v.setOnClickListener(this);
}
}
}
@Override
public void onClick(View arg0) {
Intent a = new Intent(Softkeys.this, Bmod.class);
if (arg0.getId() == R.id.b1) {
a.putExtra("Stock", "stock");
startActivity(a);
} else if (arg0.getId() == R.id.b2) {
a.putExtra("StockBlue", "stockblue");
startActivity(a);
} else if (arg0.getId() == R.id.b3) {
a.putExtra("Green", "green");
startActivity(a);
} else if (arg0.getId() == R.id.b4) {
a.putExtra("Pink", "pink");
startActivity(a);
} else if (arg0.getId() == R.id.b5) {
a.putExtra("Purple", "purple");
startActivity(a);
} else if (arg0.getId() == R.id.b6) {
a.putExtra("Yellow", "yellow");
startActivity(a);
} else if (arg0.getId() == R.id.b7) {
a.putExtra("Red", "red");
startActivity(a);
} else if (arg0.getId() == R.id.b8) {
a.putExtra("Galaxy", "galaxy");
startActivity(a);
} else if (arg0.getId() == R.id.b9) {
a.putExtra("GalaxyBlue", "galaxyblue");
startActivity(a);
} else if (arg0.getId() == R.id.b10) {
a.putExtra("Reflect", "Reflect");
startActivity(a);
} else if (arg0.getId() == R.id.b11) {
a.putExtra("ReflectBlue", "reflect");
startActivity(a);
} else if (arg0.getId() == R.id.b12) {
a.putExtra("Razor", "razor");
startActivity(a);
} else if (arg0.getId() == R.id.b13) {
a.putExtra("RazorBlue", "razorblue");
startActivity(a);
} else if (arg0.getId() == R.id.b14) {
a.putExtra("Small", "small");
startActivity(a);
} else if (arg0.getId() == R.id.b15) {
a.putExtra("SmallBlue", "smallblue");
startActivity(a);
} else if (arg0.getId() == R.id.b16) {
a.putExtra("SmallReflect", "smallreflect");
startActivity(a);
} else if (arg0.getId() == R.id.b17) {
a.putExtra("SmallReflectBlue", "smallreflectblue");
startActivity(a);
} else if (arg0.getId() == R.id.b18) {
a.putExtra("Xperia", "xperia");
startActivity(a);
} else if (arg0.getId() == R.id.b19) {
a.putExtra("XperiaBlue", "xperiablue");
startActivity(a);
} else if (arg0.getId() == R.id.b20) {
a.putExtra("Zte", "zte");
startActivity(a);
} else if (arg0.getId() == R.id.b21) {
a.putExtra("ZteBlue", "zteblue");
startActivity(a);
} else if (arg0.getId() == R.id.b22) {
a.putExtra("College", "college");
startActivity(a);
} else if (arg0.getId() == R.id.b23) {
a.putExtra("CollegeBlue", "collegeblue");
startActivity(a);
} else if (arg0.getId() == R.id.b24) {
a.putExtra("Defused", "defused");
startActivity(a);
} else if (arg0.getId() == R.id.b25) {
a.putExtra("DefusedBlue", "defusedblue");
startActivity(a);
} else if (arg0.getId() == R.id.b26) {
a.putExtra("Droid", "droid");
startActivity(a);
} else if (arg0.getId() == R.id.b27) {
a.putExtra("DroidBlue", "droidblue");
startActivity(a);
} else if (arg0.getId() == R.id.b28) {
a.putExtra("Pixel", "pixel");
startActivity(a);
} else if (arg0.getId() == R.id.b29) {
a.putExtra("PixelBlue", "pixelsblue");
startActivity(a);
} else if (arg0.getId() == R.id.b30){
a.putExtra("Facebook", "facebook");
startActivity(a);
}
}
@Override
public boolean onDown(MotionEvent arg0) {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
if (e1.getX() - e2.getX() > SWIPE_MIN_DISTANCE
&& Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
Toast.makeText(Softkeys.this, "Right to left",
Toast.LENGTH_LONG).show();
Log.i("tag", "Right to left");
return true; // Right to left
} else if (e2.getX() - e1.getX() > SWIPE_MIN_DISTANCE
&& Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
Toast.makeText(Softkeys.this, "Left to right",
Toast.LENGTH_LONG).show();
Log.i("tag", "Left to right");
return true; // Left to right
}
return false;
}
@Override
public void onLongPress(MotionEvent arg0) {
Intent in = new Intent(Softkeys.this, MainActivity.class);
startActivity(in);
}
@Override
public boolean onScroll(MotionEvent arg0, MotionEvent arg1, float arg2,
float arg3) {
// TODO Auto-generated method stub
return false;
}
@Override
public void onShowPress(MotionEvent arg0) {
// TODO Auto-generated method stub
}
@Override
public boolean onSingleTapUp(MotionEvent arg0) {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean onTouchEvent(MotionEvent me) {
return gestureDetector.onTouchEvent(me);
}
}
对不起，有点大。无论如何，这是日志：
04-10 22:34:28.221: E/InputEventReceiver(3256): Exception dispatching input event.
04-10 22:34:28.221: E/MessageQueue-JNI(3256): Exception in MessageQueue callback: handleReceiveCallback
04-10 22:34:28.221: E/MessageQueue-JNI(3256): java.lang.NullPointerException
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at com.cydeon.plasmamodz.Softkeys.onTouchEvent(Softkeys.java:282)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at android.app.Activity.dispatchTouchEvent(Activity.java:2413)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:2120)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at android.view.View.dispatchPointerEvent(View.java:7426)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at android.view.ViewRootImpl.deliverPointerEvent(ViewRootImpl.java:3220)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at android.view.ViewRootImpl.deliverInputEvent(ViewRootImpl.java:3165)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at android.view.ViewRootImpl.doProcessInputEvents(ViewRootImpl.java:4292)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at android.view.ViewRootImpl.enqueueInputEvent(ViewRootImpl.java:4271)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at android.view.ViewRootImpl$WindowInputEventReceiver.onInputEvent(ViewRootImpl.java:4363)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at android.view.InputEventReceiver.dispatchInputEvent(InputEventReceiver.java:179)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at android.os.MessageQueue.nativePollOnce(Native Method)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at android.os.MessageQueue.next(MessageQueue.java:125)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at android.os.Looper.loop(Looper.java:124)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at android.app.ActivityThread.main(ActivityThread.java:5235)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at java.lang.reflect.Method.invokeNative(Native Method)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at java.lang.reflect.Method.invoke(Method.java:511)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:795)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:562)
04-10 22:34:28.221: E/MessageQueue-JNI(3256): at dalvik.system.NativeStart.main(Native Method)
04-10 22:34:28.229: E/AndroidRuntime(3256): FATAL EXCEPTION: main
04-10 22:34:28.229: E/AndroidRuntime(3256): java.lang.NullPointerException
04-10 22:34:28.229: E/AndroidRuntime(3256): at com.cydeon.plasmamodz.Softkeys.onTouchEvent(Softkeys.java:282)
04-10 22:34:28.229: E/AndroidRuntime(3256): at android.app.Activity.dispatchTouchEvent(Activity.java:2413)
04-10 22:34:28.229: E/AndroidRuntime(3256): at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:2120)
04-10 22:34:28.229: E/AndroidRuntime(3256): at android.view.View.dispatchPointerEvent(View.java:7426)
04-10 22:34:28.229: E/AndroidRuntime(3256): at android.view.ViewRootImpl.deliverPointerEvent(ViewRootImpl.java:3220)
04-10 22:34:28.229: E/AndroidRuntime(3256): at android.view.ViewRootImpl.deliverInputEvent(ViewRootImpl.java:3165)
04-10 22:34:28.229: E/AndroidRuntime(3256): at android.view.ViewRootImpl.doProcessInputEvents(ViewRootImpl.java:4292)
04-10 22:34:28.229: E/AndroidRuntime(3256): at android.view.ViewRootImpl.enqueueInputEvent(ViewRootImpl.java:4271)
04-10 22:34:28.229: E/AndroidRuntime(3256): at android.view.ViewRootImpl$WindowInputEventReceiver.onInputEvent(ViewRootImpl.java:4363)
04-10 22:34:28.229: E/AndroidRuntime(3256): at android.view.InputEventReceiver.dispatchInputEvent(InputEventReceiver.java:179)
04-10 22:34:28.229: E/AndroidRuntime(3256): at android.os.MessageQueue.nativePollOnce(Native Method)
04-10 22:34:28.229: E/AndroidRuntime(3256): at android.os.MessageQueue.next(MessageQueue.java:125)
04-10 22:34:28.229: E/AndroidRuntime(3256): at android.os.Looper.loop(Looper.java:124)
04-10 22:34:28.229: E/AndroidRuntime(3256): at android.app.ActivityThread.main(ActivityThread.java:5235)
04-10 22:34:28.229: E/AndroidRuntime(3256): at java.lang.reflect.Method.invokeNative(Native Method)
04-10 22:34:28.229: E/AndroidRuntime(3256): at java.lang.reflect.Method.invoke(Method.java:511)
04-10 22:34:28.229: E/AndroidRuntime(3256): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:795)
04-10 22:34:28.229: E/AndroidRuntime(3256): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:562)
04-10 22:34:28.229: E/AndroidRuntime(3256): at dalvik.system.NativeStart.main(Native Method)