Question

我有一个使用CoordinatorLayout和NavigationDrawer的应用。但是，每当我打开NavigationView时（通过从设备屏幕的边缘滑动），我的应用程序崩溃时出现以下错误：

java.lang.NullPointerException: Attempt to invoke virtual method 'float android.view.MotionEvent.getX()' on a null object reference
        at android.view.View.onTouchEvent(View.java:9409)
        at android.support.design.widget.CoordinatorLayout.onTouchEvent(CoordinatorLayout.java:449)
        at android.view.View.dispatchTouchEvent(View.java:8471)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2373)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2092)
        at android.support.v4.widget.DrawerLayout.cancelChildViewTouch(DrawerLayout.java:1668)
        at android.support.v4.widget.DrawerLayout$ViewDragCallback.peekDrawer(DrawerLayout.java:1916)
        at android.support.v4.widget.DrawerLayout$ViewDragCallback.access$000(DrawerLayout.java:1801)
        at android.support.v4.widget.DrawerLayout$ViewDragCallback$1.run(DrawerLayout.java:1807)
        at android.os.Handler.handleCallback(Handler.java:739)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:135)
        at android.app.ActivityThread.main(ActivityThread.java:5254)
        at java.lang.reflect.Method.invoke(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:372)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)

我尝试重写触摸事件方法：

@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
    try {
        return super.dispatchTouchEvent(ev);
    } catch (Exception e) {
        return false;
    }
}

@Override
public boolean onTouchEvent(MotionEvent ev) {
    try {
        return super.onTouchEvent(ev);
    } catch (Exception e) {
        return false;
    }
}

但这没有帮助。无论如何我可以解决这个错误吗？

赞赏所有建议

Answer 1

好吧，所以我能够解决问题：

覆盖我的问题中显示的方法：

@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
    try {
        return super.dispatchTouchEvent(ev);
    } catch (Exception e) {
        return false;
    }
}

@Override
public boolean onTouchEvent(MotionEvent ev) {
    try {
        return super.onTouchEvent(ev);
    } catch (Exception e) {
        return false;
    }
}

并为我的CoordinatorLayout设置onTouchListener：

coordinatorLayout.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            return true; //make sure to return true
        }
    });

应用程序崩溃与NavigationView和CoordinatorLayout触摸事件

1 个答案: