Question

我的问题：在FragmentActivity中使用onTouchEvent是否有解决办法？

我的情况：我正在编写一个简单的手电筒应用程序，我有一个FragmentActivity，用户可以在颜色之间滑动（整个屏幕只有一种颜色。这个应用程序是为了个人改进）。我希望能够为选项执行onLongPress事件，使用隐藏导航栏的onDoubleTap事件，以及最重要的触摸事件来控制应用的亮度（我想让用户上下滚动亮度变化，欢迎任何想法！onFling事件对此有利吗？）

我尝试了什么：我的GestureDetector实施了SimpleOnGestureListener。我覆盖了onTouchEvent中的FragmentActivity，但我刚刚发现此方法永远不会在FragmentActivity中调用（我也在方法中使用Log.print进行了测试它永远不会被称为）。有解决方法吗？谢谢！

突出代码：

MainActivity：

public class MainActivity extends FragmentActivity {

  private GestureDetector gestureDetector;
  private FragmentPagerAdapter mAdapter;

  /**
   * Called when the activity is first created.
   */
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    gestureDetector = new GestureDetector(getApplicationContext(), new MyGestureListener(getWindow()));

    mAdapter = new ColorFragmentAdapter(getSupportFragmentManager(), getDefaultColorList());
    ViewPager pager = (ViewPager) super.findViewById(R.id.viewpager);
    pager.setAdapter(mAdapter);
    pager.setCurrentItem(Math.round(mAdapter.getCount() / 2)); //Set current fragment to middle fragment
  }

  @Override
  public boolean onTouchEvent(MotionEvent event) {
    print("Sending touch event to gestureDetector.");
    //This line is never run.
    return gestureDetector.onTouchEvent(event);
  }

  /**
   * Prints the given object to the log with the debug priority with the tag FLASHLIGHT
   *
   * @param object
   */
  public static void print(Object object) {
    Log.println(Log.DEBUG, "FLASHLIGHT", object.toString());
  }
}

MyGestureListener：

public class MyGestureListener extends SimpleOnGestureListener {

  private final Window window;

  public MyGestureListener(Window window) {
    super();
    this.window = window;
  }

  @Override
  public void onLongPress(MotionEvent e) {
    //onLongPress code
  }

  @Override
  public boolean onDoubleTap(MotionEvent e) {
    //onDoubleTap code
  }

  @Override
  public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
    //onFling cod
  }
}

main.xml中

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:orientation="vertical"
  >
  <android.support.v4.view.ViewPager
        android:id="@+android:id/viewpager"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        />
</LinearLayout>

我认为你不需要其他任何东西来回答这个问题，但如果你这样做，请告诉我。

Answer 1

因此解决方案相对容易。问题是ViewPager正在吃触摸事件。所以我所做的就是编写自己的ViewPager实现，并通过调用onTouchEvent(MotionEvent event)覆盖super.onTouchEvent(event)方法，然后将事件传递给类中的gestureDetector。

相关代码：

MainActivity

public class MainActivity extends FragmentActivity {

  private FragmentPagerAdapter mAdapter;

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.layout_main);
    mAdapter = new FragmentAdapter(getSupportFragmentManager());
    MyViewPager pager = (MyViewPager) findViewById(R.id.viewpager);
    pager.setGestureDetector(new GestureDetector(this, new MyGestureListener(this)));
    pager.setAdapter(mAdapter);
    pager.setCurrentItem(Math.round(mAdapter.getCount() / 2));
  }
}

MyViewPager

public class MyViewPager extends ViewPager {

  private GestureDetector gestureDetector;

  public MyViewPager(Context context) {
    super(context);
  }

  public MyViewPager(Context context, AttributeSet attrs) {
    super(context, attrs);
  }

  @Override
  public boolean onTouchEvent(MotionEvent e) {
    return super.onTouchEvent(e) && gestureDetector.onTouchEvent(e);
  }
}

MyGestureListener

public class MyGestureListener extends SimpleOnGestureListener {

  private final Activity activity;

  public MyGestureListener(Activity activity) {
    super();
    this.activity = activity;
  }

  @Override
  public boolean onDoubleTap(MotionEvent e) {
    //...
  }

  @Override
  public boolean onSingleTapConfirmed(MotionEvent e) {
    //...
  }

//... etc...

}

layout_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:orientation="vertical"
>
  <com.kentcdodds.flashlight.MyViewPager
    android:id="@+android:id/viewpager"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
        />
</LinearLayout>

Answer 2

尝试这样做：

gestureDetector = new GestureDetector(this);

并在TouchEvent上：

   @Override
   public boolean onTouchEvent(MotionEvent me) {
    return gestureDetector.onTouchEvent(me);
}

Source

Answer 3

如果您只想检测用户何时触及fragmentActivity，请使用以下方法：

public void onUserInteraction(){
  Log.d("FragmentActivity","touched");
}

更多信息：http://developer.android.com/reference/android/support/v4/app/FragmentActivity.html

如何使用FragmentActivity实现onTouchEvent

3 个答案: