关于android：onTouchListener警告：检测到点击时，onTouch应调用View#performClick

onTouchListener warning: onTouch should call View#performClick when a click is detected

我创建了一个onTouchListener。不幸的是onTouch()方法throws给我一个警告：

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com/calculator/activitys/Calculator$1#onTouch should call View#performClick when a click is detected

是什么意思？我尚未找到有关此警告的任何信息。这是完整的代码：

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LinearLayout llCalculatorContent = (LinearLayout) fragmentView.findViewById(R.id.calculator_content);

llCalculatorContent.setOnTouchListener(new View.OnTouchListener() {

@Override
public boolean onTouch(View v, MotionEvent event) {
Tools.hideKeyboard(getActivity(), getView());
getView().clearFocus();
return false;
}
});

相关讨论

如果您没有使用显式覆盖onPerformClick的Custom View，则仅遵循Secko的回答就不会消除警告。

除了他的答案外，要在android.widget.Button或Button之类的类上执行相同的操作，您需要制作一个简单的自定义视图，以扩展目标视图。

示例：

自定义视图类：

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public class UselessButton extends AppCompatButton {
public UselessButton(Context context) {
super(context);
}

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

public UselessButton(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}

@Override
public boolean performClick() {
return super.performClick();
}
}

XML：

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<stackoverflow.onEarth.UselessButton
android:id="@+id/left"
android:layout_width="60dp"
android:layout_height="60dp"
android:layout_marginStart="16dp"
android:layout_marginTop="16dp"
android:layout_marginEnd="8dp"
android:layout_marginBottom="8dp"
android:background="@drawable/left"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.16"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBaseline_toBaselineOf="@+id/right"
app:layout_constraintVertical_bias="0.5" />

Java：

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left.setOnTouchListener((v, event) -> {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
enLeft = 1;
enRight = 0;
return true;
} else if (event.getAction() == MotionEvent.ACTION_UP) {
enLeft = 0;
v.performClick();
return false;
} else {
return false;
}
});

当前问题：警告已通过IDE解决，但无法在实际的Android设备上看到此按钮实际上执行的点击操作。

编辑：修复了获取点击事件：使用View.setPressed(boolean)

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down.setOnTouchListener((v, event) -> {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
enFront = 0;
enBack = 1;
left.setPressed(true);
return true;
} else if (event.getAction() == MotionEvent.ACTION_UP) {
enBack = 0;
v.performClick();
v.setPressed(false);
return false;
} else {
return false;
}

您可以抑制皮棉

1	@SuppressLint("ClickableViewAccessibility")

您应该在onTouchEvent()内部调用performClick()。

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@Override
public boolean onTouchEvent(MotionEvent event) {
//A logic

performClick();
return super.onTouchEvent(event);
}

或

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findViewById(R.id.view1).setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {

v.performClick();

return v.onTouchEvent(event);
}
});

OnTouch流量

在此处了解更多信息

相关讨论

只需调用performClick方法，如下所示：

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@Override
public boolean onTouch(View v, MotionEvent event) {
v.performClick();
Tools.hideKeyboard(getActivity(), getView());
getView().clearFocus();
return false;
}

我在MultiTouchListener上遇到了类似的问题，并解决了它实现GestureDetector并侦听SingleTap的问题(这不会删除警告，但会在我的视图上开始触发onClick事件)

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class TouchListener(context: Context) : MultiTouchListener() {

private var tochedView: View? = null
private var mGestureDetector = CustomGestureDetector()
private var gestureDetector: GestureDetector = GestureDetector(context, mGestureDetector)

@SuppressLint("ClickableViewAccessibility")
override fun onTouch(view: View?, event: MotionEvent?): Boolean {
val aux = super.onTouch(view, event)

tochedView = view
gestureDetector.onTouchEvent(event)

return aux
}

private inner class CustomGestureDetector: GestureDetector.SimpleOnGestureListener() {

override fun onSingleTapUp(e: MotionEvent?): Boolean {
// this will be called even when a double tap is
tochedView?.performClick()
return super.onSingleTapUp(e)
}

override fun onSingleTapConfirmed(e: MotionEvent?): Boolean {
// this will only be called after the detector is confident that the
// user's first tap is not followed by a second tap leading to a double-tap gesture.
tochedView?.performClick()
return super.onSingleTapConfirmed(e)
}

}

}