Question

我正在Android Studio中创建一个非常基本的待办应用程序。当用户添加新任务时，我希望他从房屋/工作/活动中选择一种类别。为此，我在主布局中添加了PopupWindow，并在表示类别的3 imageButtons中添加了内容。房屋默认为选中状态，当用户要选择其他房屋时，houseButton将其图像更改为“空”，其他按钮将其图像更改为“选定”

根据我在互联网上发现的内容，我尝试在view.invalidate()上使用view.postInvalidate()和imageButtons，但没有任何反应。我也尝试过覆盖runOnUiThread {}中的整个块，但它也无济于事。

不起作用的监听器：

fun swapActivity(view: View) {
    houseButton.setImageResource(R.drawable.houseempty)
    workButton.setImageResource(R.drawable.workempty)
    activityButton.setImageResource(R.drawable.activityempty)
    when (view) {
        houseButton -> {
            houseButton.setImageResource(R.drawable.house)
            selectedActivity = "house"
        }
        workButton -> {
            workButton.setImageResource(R.drawable.work)
            selectedActivity = "work"
        }
        aActivity -> {
            activityButton.setImageResource(R.drawable.activity)
            selectedActivity = "activ"
        }
    }
}

主布局中显示PopupWindow的按钮：

var shown = false
button.setOnClickListener{
    if(!shown) {
        shown = true
        val inflater: LayoutInflater = getSystemService(Context.LAYOUT_INFLATER_SERVICE) as LayoutInflater
        val view = inflater.inflate(R.layout.new_todo, null)
        val popupWindow = PopupWindow(
            view,
            LinearLayout.LayoutParams.MATCH_PARENT, 
            LinearLayout.LayoutParams.WRAP_CONTENT
        )
        //imageView inside popup that hides it
        val buttonPopup = view.findViewById<ImageView>(R.id.imageCancel)
        buttonPopup.setOnClickListener {
            popupWindow.dismiss()
            shown = false
        }
        TransitionManager.beginDelayedTransition(mainLayout)
        popupWindow.showAtLocation(
            mainLayout, // Location to display popup window
            Gravity.BOTTOM,
            0,
            0
        )
    }
}

XML弹出文件（new_todo）：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              xmlns:app="http://schemas.android.com/apk/res-auto"
              xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
              android:layout_height="match_parent"
              android:background="#ffffff">">
        <ImageView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                app:srcCompat="@drawable/cancel" 
                android:id="@+id/imageCancel"/>
        <ImageButton
                android:background="@null"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content" 
                app:srcCompat="@drawable/activity"
                android:id="@+id/activityButton" 
                android:onClick="swapActivity"/>
        <ImageButton
                android:background="@null"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content" 
                app:srcCompat="@drawable/workempty"
                android:id="@+id/workButton"
                android:onClick="swapActivity"/>
        <ImageButton
                android:layout_width="wrap_content" android:background="@null"
                android:layout_height="wrap_content" 
                app:srcCompat="@drawable/house"
                android:id="@+id/houseButton"
                android:onClick="swapActivity"/>
</LinearLayout>

编辑：已解决。我删除了整个swapActivity函数，并在主按钮侦听器中添加了以下几行：

val houseButton1 = view.findViewById<ImageButton>(R.id.houseButton)
val workButton1 = view.findViewById<ImageButton>(R.id.workButton)
val activityButton1 = view.findViewById<ImageButton>(R.id.activityButton)

houseButton1.setOnClickListener {
    houseButton1.setImageResource(R.drawable.house)
    workButton1.setImageResource(R.drawable.workempty)
    activityButton1.setImageResource(R.drawable.activityempty)
    selectedActivity = "house"
}
//repeat for all buttons

如何使用onClick侦听器在PopupWindow中更改imageButton图像？

0 个答案: