我一直在努力平滑向上滑动，但不知道如何完成。实际上，我不清楚前面关于堆栈溢出的问题的答案是什么。如有任何帮助，我们将不胜感激。请用代码+解释来回答。感谢提前回复。
我有以下代码向上滑动，但它不平滑：
SimpleOnGestureListener simpleOnGestureListener = new SimpleOnGestureListener() {
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
String TAG = "TAG";
float sensitvity = 70;
if (upflag == true) {
if ((e1.getX() - e2.getX()) > sensitvity) {
Log.d(TAG, "Up Left performed");
return false;
} else if ((e2.getX() - e1.getX()) > sensitvity) {
Log.d(TAG, "Up Right performed");
return false;
}
if (e1.getY() >= e2.getY() - 100) {
Log.d(TAG, "Up swipe performed");
SharedPreferences preferences = getSharedPreferences(
"com.teneleven", MODE_PRIVATE);
if (preferences.contains("storyid") && upflag == true) {
Bundle bundle = new Bundle();
Intent i = new Intent(HomeActivity.this,
TradingRefrenceActivity.class);
((AppController) getApplicationContext())
.setRefDate(mtv_Date.getText().toString());
bundle.putString("news_id",
preferences.getString("storyid", ""));
bundle.putString("category",
preferences.getString("story_category", ""));
bundle.putString("colorcode",
preferences.getString("story_colorcode", ""));
i.putExtras(bundle);
startActivity(i);
threadFlag = false;
stopHandler();
overridePendingTransition(R.anim.push_up_in,
R.anim.push_up_out);
return true;
}
// if ((e1.getY() - e2.getY()) > sensitvity) {
// Log.d(TAG, "Up swipe performed");
// SharedPreferences preferences = getSharedPreferences(
// "com.teneleven", MODE_PRIVATE);
// if (preferences.contains("storyid")) {
// Bundle bundle = new Bundle();
// Intent i = new Intent(HomeActivity.this,
// TradingRefrenceActivity.class);
// bundle.putString("news_id",
// preferences.getString("storyid", ""));
// bundle.putString("category",
// preferences.getString("story_category", ""));
// bundle.putString("slug",
// preferences.getString("category_slug", ""));
// i.putExtras(bundle);
// startActivity(i);
//
// overridePendingTransition(R.anim.push_up_in,
// R.anim.push_up_out);
// return super.onFling(e1, e2, velocityX, velocityY);
// }
} else if ((e2.getY() - e1.getY()) > sensitvity) {
Log.d(TAG, "Down swipe performed");
return false;
} else {
Log.d(TAG, "None swipe performed");
return false;
}
return false;
}
return false;
}
};
试试这个代码，你可以将速度、最小和最大距离更改为
1） MainSwipe.class
public class MainSwipe extends AppCompatActivity implements SimpleGestureListener{
private SimpleGestureFilter detector;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.swipe_screen);
detector = new SimpleGestureFilter(this,this);
}
@Override
public boolean dispatchTouchEvent(MotionEvent me){
// Call onTouchEvent of SimpleGestureFilter class
this.detector.onTouchEvent(me);
return super.dispatchTouchEvent(me);
}
@Override
public void onSwipe(int direction) {
switch (direction) {
case SimpleGestureFilter.SWIPE_UP :
Log.e("UP","UP");
break;
}
}
@Override
public void onDoubleTap() {
Log.e("Doubletab","Doubletab");
}
}
2） 简单手势过滤器
public class SimpleGestureFilter extends GestureDetector.SimpleOnGestureListener {
public final static int SWIPE_UP = 1;
public final static int SWIPE_DOWN = 2;
public final static int SWIPE_LEFT = 3;
public final static int SWIPE_RIGHT = 4;
public final static int MODE_TRANSPARENT = 0;
public final static int MODE_SOLID = 1;
public final static int MODE_DYNAMIC = 2;
private final static int ACTION_FAKE = -13; //just an unlikely number
private int swipe_Min_Distance = 100;
private int swipe_Max_Distance = 500;
private int swipe_Min_Velocity = 100;
private int mode = MODE_DYNAMIC;
private boolean running = true;
private boolean tapIndicator = false;
private Activity context;
private GestureDetector detector;
private SimpleGestureListener listener;
public SimpleGestureFilter(Activity context,SimpleGestureListener sgl) {
this.context = context;
this.detector = new GestureDetector(context, this);
this.listener = sgl;
}
public void onTouchEvent(MotionEvent event){
if(!this.running)
return;
boolean result = this.detector.onTouchEvent(event);
if(this.mode == MODE_SOLID)
event.setAction(MotionEvent.ACTION_CANCEL);
else if (this.mode == MODE_DYNAMIC) {
if(event.getAction() == ACTION_FAKE)
event.setAction(MotionEvent.ACTION_UP);
else if (result)
event.setAction(MotionEvent.ACTION_CANCEL);
else if(this.tapIndicator){
event.setAction(MotionEvent.ACTION_DOWN);
this.tapIndicator = false;
}
}
//else just do nothing, it's Transparent
}
public void setMode(int m){
this.mode = m;
}
public int getMode(){
return this.mode;
}
public void setEnabled(boolean status){
this.running = status;
}
public void setSwipeMaxDistance(int distance){
this.swipe_Max_Distance = distance;
}
public void setSwipeMinDistance(int distance){
this.swipe_Min_Distance = distance;
}
public void setSwipeMinVelocity(int distance){
this.swipe_Min_Velocity = distance;
}
public int getSwipeMaxDistance(){
return this.swipe_Max_Distance;
}
public int getSwipeMinDistance(){
return this.swipe_Min_Distance;
}
public int getSwipeMinVelocity(){
return this.swipe_Min_Velocity;
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
final float xDistance = Math.abs(e1.getX() - e2.getX());
final float yDistance = Math.abs(e1.getY() - e2.getY());
if(xDistance > this.swipe_Max_Distance || yDistance > this.swipe_Max_Distance)
return false;
velocityX = Math.abs(velocityX);
velocityY = Math.abs(velocityY);
boolean result = false;
if(velocityX > this.swipe_Min_Velocity && xDistance > this.swipe_Min_Distance){
if(e1.getX() > e2.getX()) // right to left
this.listener.onSwipe(SWIPE_LEFT);
else
this.listener.onSwipe(SWIPE_RIGHT);
result = true;
}
else if(velocityY > this.swipe_Min_Velocity && yDistance > this.swipe_Min_Distance){
if(e1.getY() > e2.getY()) // bottom to up
this.listener.onSwipe(SWIPE_UP);
else
this.listener.onSwipe(SWIPE_DOWN);
result = true;
}
return result;
}
@Override
public boolean onSingleTapUp(MotionEvent e) {
this.tapIndicator = true;
return false;
}
@Override
public boolean onDoubleTap(MotionEvent arg) {
this.listener.onDoubleTap();;
return true;
}
@Override
public boolean onDoubleTapEvent(MotionEvent arg) {
return true;
}
@Override
public boolean onSingleTapConfirmed(MotionEvent arg) {
if(this.mode == MODE_DYNAMIC){ // we owe an ACTION_UP, so we fake an
arg.setAction(ACTION_FAKE); //action which will be converted to an ACTION_UP later.
this.context.dispatchTouchEvent(arg);
}
return false;
}
}
3） 接口SimpleGestureListener
public interface SimpleGestureListener {
void onSwipe(int direction);
void onDoubleTap();
}